Causes of death in Japanese patients with diabetes based on the results of survey of 68,555 cases during 2011–2020: committee report on causes of death in diabetes mellitus, Japan Diabetes Society (English version)

Abstract

The principal causes of death among 68,555 patients with diabetes and 164,621 patients without diabetes who died in 208 hospitals throughout Japan between 2011 and 2020 were determined based on a survey of hospital records. 1. The most frequent cause of death in patients with diabetes was malignant neoplasms (38.9%) (lung 7.8%, pancreas 6.5%, liver 4.1%), followed, in order of descending frequency, by infectious diseases (17.0%) and then vascular diseases (10.9%) (cerebrovascular diseases 5.2%, ischemic heart diseases 3.5%, renal failure 2.3%). The proportion of deaths from malignant neoplasms and vascular diseases has trended upward and downward, respectively. Almost all deaths from ischemic heart diseases were due to myocardial infarction, and the proportion of deaths from heart diseases other than ischemic heart diseases was relatively high (9.0%), with most cases due to heart failure. Diabetic coma associated with hyperglycemia accounted for only 0.3% of deaths. 2. The proportion of deaths from malignant neoplasms, infectious diseases, renal failure, ischemic heart diseases, and heart failure was significantly higher in patients with diabetes than in those without diabetes, and the proportion of deaths from cerebrovascular diseases was significantly lower in patients with diabetes. 3. In regard to the relationship between the age and cause of death in patients with diabetes, malignant neoplasms were the most frequent cause of death in all age groups, and the incidence was around 50% for those in their 50s and 60s. The incidence of death due to infectious diseases was highest in patients older than their 70s. The incidence of death due to vascular diseases for patients in their 40s and 50s was higher than that due to infectious diseases. The highest incidence of death due to ischemic heart diseases was observed for patients in their 40s, and that due to renal failure and heart failure in patients older than their 70s. 4. Compared to patients without diabetes, patients with diabetes demonstrated a higher incidence of death due to pancreas cancer, infectious diseases, renal failure, ischemic heart diseases and heart failure and lower incidence of death due to cerebrovascular diseases in all age groups. 5. The average age at death of patients with diabetes was 74.4 years old in men and 77.4 years old in women, which were lower than the average lifespan of the Japanese general population in 2020 by 7.2 and 10.3 years, respectively. However, these differences were smaller than in previous surveys. 6. The average age at death due to all causes, especially due to ischemic heart diseases, cerebrovascular diseases, heart failure, infectious diseases, and diabetic coma, was lower in patients with “poorer” glycemic control than in those with “better” glycemic control. 7. In the total survey population, the average age at death of patients with diabetes was significantly higher than that of patients without diabetes. The average age at death due to malignant neoplasms and cerebrovascular diseases was higher in patients with diabetes than in those without diabetes and that due to renal failure, ischemic heart diseases, and infectious diseases was lower in patients with diabetes than in those without diabetes.

Introduction

The goal of diabetes treatment is to ensure “lifespan and quality of life (QOL) comparable with those of people without diabetes.” To achieve this, stigma must be eliminated by preventing the onset and progression of diabetic complications as well as concomitant diseases such as malignant neoplasms. Periodic surveys on the causes of and age at death of patients with diabetes are significant in examining whether recent advances in the treatment and management of diabetes and advocacy activities contribute to the achievement of this goal.

Studies on the pathological conditions of diabetes among Japanese individuals, specifically “Study on Prevention of Onset and Suppression of Progression of Vascular Complications in Diabetes” (Japan Diabetes Complications [JDC] Study) [2] and “Large-scale Observational Study to Investigate the Current Status of Diabetic Complications and Their Prevention” (Japan Diabetes Complication and Prevention prospective [JDCP] study) [3, 4], have been conducted. The “Japan Diabetes Comprehensive Database Project Based on an Advanced Electronic Medical Record System” (J-DREAMS) [5] is in progress. These studies are expected to reveal further knowledge on diabetes in Japan. However, given the limited sample size, data on the causes of and age at death of patients with diabetes are insufficient.

Four large-scale questionnaire surveys on the causes of death of patients with diabetes had been previously conducted at 10-year intervals [6–9]. The present questionnaire survey on the causes of death in patients with diabetes was conducted similarly to the four previous surveys by the Committee of the Japan Diabetes Society on the Causes of Death in Diabetes Mellitus from 2011 to 2020. The current study analyzed the results of the present survey and compared them with the results of the previous surveys. Further, the present survey enrolled patients without diabetes in addition to patients with diabetes; these patients were also compared.

Methods

The present survey was conducted for 10 years from January 1, 2011, to December 31, 2020. Its contents were divided into two parts. The survey on the causes of death of patients with diabetes included 11 survey items: (1) sex, (2) age at death, (3) year and month of death, (4) estimated age at onset, (5) treatment duration, (6) disease type classification, (7) cause of death, (8) major complications/concomitant diseases before death, (9) methods to diagnose the cause of death, (10) treatment, and (11) the most recent hemoglobin A1c (HbA1c: National Glycohemoglobin Standardization Program [NGSP]) level. Five survey items (items 1, 2, 6, 7, and 10) were mandatory to answer. The survey on the causes of death of patients without diabetes included the mandatory items of sex, age at death, and cause of death. Although the composition of the survey items was slightly changed compared to the four previous surveys, the changes did not interfere with the comparison of analysis results.

As in the previous surveys, the present survey was distributed to 1154 institutions that met the criterion of having presented papers at an Annual Meeting of the Japan Diabetes Society during the previous 5 years (2016–2020). While the present survey targeted patients who died in an entire institution including the requested departments, the institutions were requested to enroll all patients with diabetes to the extent possible and as many patients without diabetes as the enrolled patients with diabetes. A total of 233,176 patients (68,555 with diabetes and 164,621 without diabetes) were enrolled from 208 institutions (response rate: 18%). The survey items—excluding the mandatory items and the most recent HbA1c level—were omitted from the analyses in this study given the limited input data. Focusing on malignant neoplasms, vascular diseases (diabetic nephropathy, ischemic heart diseases [myocardial infarction and angina pectoris], and cerebrovascular diseases), and infectious diseases, which were the principal causes of death, the causes of and age at death were analyzed in association with age, glycemic control, and therapeutic strategies; present results were compared with those from previous surveys and patients without diabetes.

The results of the surveys were tabulated separately according to patients with and without diabetes, sex, age groups, and glycemic control status (HbA1c: < 8.4% vs ≥ 8.4%). Measures of central tendency were expressed as mean ± standard deviation. A Chi-squared test was performed to compare the nominal variables. The Student’s t-test compared continuous variables. The level of significance (two-sided) was defined as p < 0.05. The statistical software used was IBM SPSS Statistics (Ver. 28.0.1.1 (15)). This study was approved by the ethics committee of the Japan Diabetes Society (JDS Ethics 02-013-(2)).

Results

Causes of death

Table 1 shows the causes of death among patients with and without diabetes in the present survey.

Table 1.

Causes of death in Japanese diabetic and non-diabetic subjects

Number	Diabetic		Non-diabetic		p-values
	Total	68,555	Total	1,64,621
	(%)	(n)	(%)	(n)
Causes of death
Vascular diseases	10.9	7489	11.3	18,607	0.008
Chronic renal failure	2.3	1569	1.1	1758	< 0.001
Diabetic nephropathy	1.6	1091
Non-diabetic nephropathy	0.7	478
Ischemic heart diseases	3.5	2378	3.0	4881	< 0.001
Myocardial infarction	3.3	2,279	2.9	4703	< 0.001
Angina pectoris	0.1	99	0.1	178	0.02
Cerebrovascular diseases	5.2	3542	7.3	11,968	< 0.001
Hemorrhage	2.1	1419	2.7	4438	< 0.001
Infarction	2.0	1388	1.9	3,187	0.159
Subarachnoidal hemorrhage	0.5	318	1.8	2908	< 0.001
Others	0.6	417	0.9	1435	< 0.001
Heart diseases (other than ischemic heart diseases)	9.0	6176	7.9	13,081	< 0.001
Arrhythmia	0.9	585	0.8	1258	0.027
Heart failure	6.0	4133	4.4	7313	< 0.001
Others	2.1	1458	2.7	4510	< 0.001
Diabetic coma	0.3	190	0.0	0	< 0.001
Hypoglycemic coma	0.1	90	0.0	46	< 0.001
Malignant neoplasia	38.9	26,644	35.4	58,354	< 0.001
Esophagus	1.0	662	1.4	2271	< 0.001
Stomach	2.9	2008	3.9	6473	< 0.001
Lung	7.8	5314	7.0	11,446	< 0.001
Colon	2.9	2020	3.4	5575	< 0.001
Liver	4.1	2842	2.6	4360	< 0.001
Pancreas	6.5	4434	2.7	4376	< 0.001
Uterus	0.5	363	0.9	1449	< 0.001
Breast	0.8	570	1.3	2210	< 0.001
Leukemia/Lymphoma	3.6	2488	2.6	4315	< 0.001
Others	8.7	5943	9.6	15,879	< 0.001
Infectious diseases	17.0	11,628	14.5	23,917	< 0.001
Tuberculosis	0.1	95	0.1	237	< 0.001
Pneumonia	11.4	7819	10.8	17,833	< 0.001
Others	5.4	3714	3.6	5847	< 0.001
Liver cirrhosis	2.1	1452	1.5	2412	< 0.001
Type B	0.1	89	0.1	124	< 0.001
Type C	0.6	425	0.4	695	< 0.001
NAFLD	0.2	153	0.1	103	< 0.001
Others	1.1	785	0.9	1490	< 0.001
Suicide	0.2	132	1.0	1674	< 0.001
Others	18.0	12,353	23.2	38,248	< 0.001
Unknown	3.5	2401	5.0	8282	< 0.001

Causes of death in patients with diabetes

In 68,555 patients with diabetes, the most frequent cause of death was malignant neoplasms, accounting for 26,644 patients (38.9%), followed by infectious diseases and vascular diseases (chronic renal failure, ischemic heart diseases, and cerebrovascular diseases), accounting for 11,628 (17.0%) and 7,489 (10.9%) patients, respectively. Among malignant neoplasms, lung cancer was most common, accounting for 5314 patients (7.8%), followed by pancreatic and liver cancers accounting for 4434 (6.5%) and 2842 (4.1%) patients, respectively. Among vascular diseases, cerebrovascular diseases and ischemic heart diseases were reported in 3,542 patients (5.2%) and 2378 patients (3.5%), respectively, while chronic renal failure was reported in 1569 patients (2.3%). Among ischemic heart diseases, angina pectoris accounted for 0.1%, and most deaths from ischemic heart diseases were due to myocardial infarction. Among cerebrovascular diseases, cerebral hemorrhage and cerebral infarction were almost equally common, accounting for 1419 patients (2.1%) and 1388 patients (2.0%), respectively. Further, heart diseases other than ischemic heart diseases were reported in 6176 patients (9.0%); most accounting for 4133 patients (6.0%), died from heart failure. Among infectious diseases, pneumonia was reported in 7819 patients (11.4%), accounting for 67.2% of all the deaths from infections. Diabetic and hypoglycemic coma were reported in 190 (0.3%) and 90 (0.1%) patients, respectively.

Comparison of the causes of death between patients with and without diabetes

In patients without diabetes, the most frequent cause of death was also malignant neoplasms, followed by infectious and then vascular diseases. Although the distribution of the causes of death was similar to that of patients with diabetes, statistically significant differences were observed in all causes of death between patients with and without diabetes. Among the principal causes of death, the proportions of deaths from malignant neoplasms and infectious diseases were significantly higher in patients with diabetes than in patients without diabetes, but the proportion of deaths from vascular diseases was significantly lower in the patients with diabetes. Among malignant neoplasms, the proportions of deaths from lung, pancreatic, and liver cancers were all significantly higher in patients with diabetes; pancreatic cancer showed the largest difference between patients with and without diabetes. Among vascular diseases, the proportions of deaths from chronic renal failure and ischemic heart diseases were significantly higher in patients with diabetes. In contrast, the proportion of deaths from cerebrovascular diseases was significantly lower; the proportions of deaths from cerebral and subarachnoid hemorrhages were lower, but no significant difference existed in the proportion of deaths from cerebral infarction. The proportion of deaths from heart failure as a heart disease separate from ischemic heart disease was also significantly higher in patients with diabetes.

Sex differences in the causes of death

The sex differences in the causes of death were comparable between patients with and without diabetes (Table 2). In patients with diabetes, malignant neoplasms were the most frequent cause of death in both men and women. The proportions of deaths from malignant neoplasms—especially esophageal, gastric, lung, and liver cancers—were higher in men than in women, whereas the proportion of deaths from pancreatic cancer was higher in women. The overall proportion of deaths from vascular diseases was higher in women than in men. The same tendency was observed for both chronic renal failure and cerebrovascular diseases, whereas no difference was observed for ischemic heart diseases. In addition, the proportion of deaths from heart failure as a heart disease separate from ischemic heart disease was higher in women, whereas that from infectious diseases (especially pneumonia) was higher in men.

Table 2.

Causes of death in Japanese diabetic and non-diabetic subjects: sex difference

Sex and number	Diabetic				Non-diabetic
	Male	45,653	Female	22,902	Male	94,021	Female	70,600
	(%)	(n)	(%)	(n)	(%)	(n)	(%)	(n)
Causes of death
Vascular diseases	10.3	4716	12.1	2773	10.5	9888	12.3	8719
Chronic renal failure	2.1	949	2.7	620	1.1	1002	1.1	756
Diabetic nephropathy	1.5	674	1.8	417
Non-diabetic nephropathy	0.6	275	0.9	203
Ischemic heart diseases	3.5	1585	3.5	793	3.1	2958	2.7	1923
Myocardial infarction	3.3	1508	3.4	771	3.0	2851	2.6	1852
Angina pectoris	0.2	77	0.1	22	0.1	107	0.1	71
Cerebrovascular diseases	4.8	2182	5.9	1360	6.3	5928	8.6	6040
Hemorrhage	2.1	974	1.9	445	2.7	2503	2.7	1935
Infarction	1.7	793	2.6	595	1.6	1480	2.4	1707
Subarachnoidal hemorrhage	0.3	157	0.7	161	1.2	1105	2.6	1803
Others	0.6	258	0.7	159	0.9	840	0.8	595
Heart diseases (other than ischemic heart diseases)	8.0	3640	11.1	2536	7.1	6635	9.1	6446
Arrythmia	0.9	414	0.7	171	0.8	762	0.7	496
Heart failure	5.1	2346	7.8	1787	3.7	3448	5.5	3865
Others	1.9	880	2.5	578	2.6	2425	3.0	2085
Diabetic coma	0.2	94	0.4	96	0.0	0	0.0	0
Hypoglycemic coma	0.1	54	0.2	36	0.0	25	0.0	21
Malignant neoplasia	40.6	18,528	35.4	8116	36.9	34,736	33.5	23,618
Esophagus	1.3	585	0.3	77	2.0	1918	0.5	353
Stomach	3.3	1509	2.2	499	4.6	4304	3.1	2169
Lung	9.6	4362	4.2	952	8.7	8214	4.6	3232
Colon	3.0	1380	2.8	640	3.3	3102	3.5	2473
Liver	4.6	2109	3.2	733	3.2	2994	1.9	1366
Pancreas	6.1	2784	7.2	1650	2.4	2291	3.0	2085
Uterus	0.0	2	1.6	361	0.0	9	2.0	1440
Breast	0.0	13	2.4	557	0.0	27	3.1	2183
Leukemia/Lymphoma	3.7	1709	3.4	779	2.7	2558	2.5	1757
Others	8.9	4075	8.2	1868	9.9	9319	9.3	6560
Infectious diseases	17.4	7933	16.1	3695	15.4	14,445	13.4	9472
Tuberculosis	0.1	56	0.2	39	0.2	157	0.1	80
Pneumonia	12.3	5604	9.7	2215	11.9	11,231	9.4	6602
Others	5.0	2273	6.3	1441	3.3	3057	4.0	2790
Liver cirrhosis	2.0	915	2.3	537	1.5	1428	1.4	984
Type B	0.1	55	0.1	34	0.1	86	0.1	38
Type C	0.6	252	0.8	173	0.4	340	0.5	355
NAFLD	0.2	80	0.3	73	0.0	34	0.1	69
Others	1.2	528	1.1	257	1.0	968	0.7	522
Suicide	0.2	96	0.2	36	1.1	988	1.0	686
Others	17.6	8039	18.8	4314	22.6	21,252	24.1	16,996
Unknown	3.6	1638	3.3	763	4.9	4624	5.2	3658

Causes of death in patients with diabetes according to age group

Table 3 shows the causes of death in patients with diabetes according to age group. Few patients were in their 20 s or younger (0.2% of all patients). The analysis of the causes of death according to age group was thus performed in patients aged 30 years or older.

Table 3.

Causes of death at specified ages in Japanese diabetic subjects

Age at death (years)	0 ~ 9						10 ~ 19
Sex and number	Male		Female		Total		Male		Female		Total
Causes of death	15	(100.0%)	13	(100.0%)	28	(100.0%)	27	(100.0%)	17	(100.0%)	44	(100.0%)
Vascular diseases	1	(6.7)	3	(23.1)	4	(14.3)	1	(3.7)	0	(0.0)	1	(2.3)
Chronic renal failure	0	(0.0)	0	(0.0)	0	(0.0)	1	(3.7)	0	(0.0)	1	(2.3)
Diabetic nephropathy	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Non-diabetic nephropathy	0	(0.0)	0	(0.0)	0	(0.0)	1	(3.7)	0	(0.0)	1	(2.3)
Ischemic heart diseases	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Myocardial infarction	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Angina pectoris	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Cerebrovascular diseases	1	(6.7)	3	(23.1)	4	(14.3)	0	(0.0)	0	(0.0)	0	(0.0)
Hemorrhage	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Infarction	0	(0.0)	1	(7.7)	1	(3.6)	0	(0.0)	0	(0.0)	0	(0.0)
Subarachnoidal hemorrhage	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Others	1	(6.7)	2	(15.4)	3	(10.7)	0	(0.0)	0	(0.0)	0	(0.0)
Heart diseases (other than ischemic heart diseases)	5	(33.3)	2	(15.4)	7	(25.0)	1	(3.7)	1	(5.9)	2	(4.5)
Arrhythmia	1	(6.7)	1	(7.7)	2	(7.1)	0	(0.0)	0	(0.0)	0	(0.0)
Heart failure	0	(0.0)	1	(7.7)	1	(3.6)	0	(0.0)	1	(5.9)	1	(2.3)
Others	4	(26.7)	0	(0.0)	4	(14.3)	1	(3.7)	0	(0.0)	1	(2.3)
Diabetic coma	0	(0.0)	0	(0.0)	0	(0.0)	2	(7.4)	0	(0.0)	2	(4.5)
Hypoglycemic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Malignant neoplasia	4	(26.7)	2	(15.4)	6	(21.4)	17	(63.0)	7	(41.2)	24	(54.5)
Esophagus	0	(0.0)	0	(0.0)	0	(0.0)	1	(3.7)	0	(0.0)	1	(2.3)
Stomach	1	(6.7)	1	(7.7)	2	(7.1)	0	(0.0)	0	(0.0)	0	(0.0)
Lung	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Colon	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Liver	0	(0.0)	0	(0.0)	0	(0.0)	1	(3.7)	0	(0.0)	1	(2.3)
Pancreas	1	(6.7)	1	(7.7)	2	(7.1)	0	(0.0)	0	(0.0)	0	(0.0)
Uterus	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Breast	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Leukemia/Lymphoma	2	(13.3)	0	(0.0)	2	(7.1)	9	(33.3)	6	(35.3)	15	(34.1)
Others	0	(0.0)	0	(0.0)	0	(0.0)	6	(22.2)	1	(5.9)	7	(15.9)
Infectious diseases	2	(13.3)	1	(7.7)	3	(10.7)	1	(3.7)	2	(11.8)	3	(6.8)
Tuberculosis	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Pneumonia	1	(6.7)	1	(7.7)	2	(7.1)	1	(3.7)	2	(11.8)	3	(6.8)
Others	1	(6.7)	0	(0.0)	1	(3.6)	0	(0.0)	0	(0.0)	0	(0.0)
Liver cirrhosis	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Type B	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Type C	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
NAFLD	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Others	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Suicide	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Others	3	(20.0)	5	(38.5)	8	(28.6)	5	(18.5)	6	(35.3)	11	(25.0)
Unknown	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	1	(5.9)	1	(2.3)

Age at death (years)	20 ~ 29						30 ~ 39						40 ~ 49
Sex and number	Male		Female		Total		Male		Female		Total		Male		Female		Total
Causes of death	54	(100.0%)	30	(100.0%)	84	(100.0%)	165	(100.0%)	99	(100.0%)	264	(100.0%)	838	(100.0%)	405	(100.0%)	1243	(100.0%)
Vascular diseases	4	(7.4)	1	(3.3)	5	(6.0)	20	(12.1)	11	(11.1)	31	(11.7)	145	(17.3)	44	(10.9)	189	(15.2)
Chronic renal failure	0	(0.0)	1	(3.3)	1	(1.2)	3	(1.8)	2	(2.0)	5	(1.9)	13	(1.6)	6	(1.5)	19	(1.5)
Diabetic nephropathy	0	(0.0)	0	(0.0)	0	(0.0)	3	(1.8)	1	(1.0)	4	(1.5)	8	(1.0)	4	(1.0)	12	(1.0)
Non-diabetic nephropathy	0	(0.0)	1	(3.3)	1	(1.2)	0	(0.0)	1	(1.0)	1	(0.4)	5	(0.6)	2	(0.5)	7	(0.6)
Ischemic heart diseases	0	(0.0)	0	(0.0)	0	(0.0)	5	(3.0)	1	(1.0)	6	(2.3)	60	(7.2)	10	(2.5)	70	(5.6)
Myocardial infarction	0	(0.0)	0	(0.0)	0	(0.0)	5	(3.0)	1	(1.0)	6	(2.3)	60	(7.2)	10	(2.5)	70	(5.6)
Angina pectoris	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Cerebrovascular diseases	4	(7.4)	0	(0.0)	4	(4.8)	12	(7.3)	8	(8.1)	20	(7.6)	72	(8.6)	28	(6.9)	100	(8.0)
Hemorrhage	1	(1.9)	0	(0.0)	1	(1.2)	8	(4.8)	6	(6.1)	14	(5.3)	44	(5.3)	14	(3.5)	58	(4.7)
Infarction	2	(3.7)	0	(0.0)	2	(2.4)	1	(0.6)	2	(2.0)	3	(1.1)	13	(1.6)	7	(1.7)	20	(1.6)
Subarachnoidal hemorrhage	1	(1.9)	0	(0.0)	1	(1.2)	1	(0.6)	0	(0.0)	1	(0.4)	12	(1.4)	3	(0.7)	15	(1.2)
Others	0	(0.0)	0	(0.0)	0	(0.0)	2	(1.2)	0	(0.0)	2	(0.8)	3	(0.4)	4	(1.0)	7	(0.6)
Heart diseases (other than ischemic heart diseases)	3	(5.6)	3	(10.0)	6	(7.1)	17	(10.3)	9	(9.1)	26	(9.8)	68	(8.1)	22	(5.4)	90	(7.2)
Arrhythmia	0	(0.0)	0	(0.0)	0	(0.0)	2	(1.2)	0	(0.0)	2	(0.8)	18	(2.1)	2	(0.5)	20	(1.6)
Heart failure	1	(1.9)	1	(3.3)	2	(2.4)	6	(3.6)	5	(5.1)	11	(4.2)	24	(2.9)	8	(2.0)	32	(2.6)
Others	2	(3.7)	2	(6.7)	4	(4.8)	9	(5.5)	4	(4.0)	13	(4.9)	26	(3.1)	12	(3.0)	38	(3.1)
Diabetic coma	2	(3.7)	1	(3.3)	3	(3.6)	4	(2.4)	1	(1.0)	5	(1.9)	10	(1.2)	4	(1.0)	14	(1.1)
Hypoglycemic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	2	(0.2)	1	(0.2)	3	(0.2)
Malignant neoplasia	21	(38.9)	12	(40.0)	33	(39.3)	37	(22.4)	32	(32.3)	69	(26.1)	276	(32.9)	182	(44.9)	458	(36.8)
Esophagus	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	2	(0.2)	2	(0.5)	4	(0.3)
Stomach	1	(1.9)	0	(0.0)	1	(1.2)	1	(0.6)	2	(2.0)	3	(1.1)	10	(1.2)	7	(1.7)	17	(1.4)
Lung	0	(0.0)	0	(0.0)	0	(0.0)	4	(2.4)	1	(1.0)	5	(1.9)	31	(3.7)	8	(2.0)	39	(3.1)
Colon	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	27	(3.2)	5	(1.2)	32	(2.6)
Liver	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	16	(1.9)	2	(0.5)	18	(1.4)
Pancreas	1	(1.9)	0	(0.0)	1	(1.2)	5	(3.0)	1	(1.0)	6	(2.3)	62	(7.4)	22	(5.4)	84	(6.8)
Uterus	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	7	(7.1)	7	(2.7)	0	(0.0)	34	(8.4)	34	(2.7)
Breast	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	2	(2.0)	2	(0.8)	0	(0.0)	36	(8.9)	36	(2.9)
Leukemia/Lymphoma	13	(24.1)	9	(30.0)	22	(26.2)	20	(12.1)	11	(11.1)	31	(11.7)	73	(8.7)	23	(5.7)	96	(7.7)
Others	6	(11.1)	3	(10.0)	9	(10.7)	7	(4.2)	8	(8.1)	15	(5.7)	55	(6.6)	43	(10.6)	98	(7.9)
Infectious diseases	5	(9.3)	1	(3.3)	6	(7.1)	28	(17.0)	12	(12.1)	40	(15.2)	88	(10.5)	36	(8.9)	124	(10.0)
Tuberculosis	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Pneumonia	4	(7.4)	0	(0.0)	4	(4.8)	13	(7.9)	3	(3.0)	16	(6.1)	36	(4.3)	14	(3.5)	50	(4.0)
Others	1	(1.9)	1	(3.3)	2	(2.4)	15	(9.1)	9	(9.1)	24	(9.1)	52	(6.2)	22	(5.4)	74	(6.0)
Liver cirrhosis	1	(1.9)	1	(3.3)	2	(2.4)	8	(4.8)	3	(3.0)	11	(4.2)	47	(5.6)	19	(4.7)	66	(5.3)
Type B	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	4	(0.5)	2	(0.5)	6	(0.5)
Type C	0	(0.0)	0	(0.0)	0	(0.0)	1	(0.6)	0	(0.0)	1	(0.4)	6	(0.7)	1	(0.2)	7	(0.6)
NAFLD	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	7	(0.8)	0	(0.0)	7	(0.6)
Others	1	(1.9)	1	(3.3)	2	(2.4)	7	(4.2)	3	(3.0)	10	(3.8)	30	(3.6)	16	(4.0)	46	(3.7)
Suicide	1	(1.9)	1	(3.3)	2	(2.4)	4	(2.4)	2	(2.0)	6	(2.3)	9	(1.1)	6	(1.5)	15	(1.2)
Others	14	(25.9)	9	(30.0)	23	(27.4)	40	(24.2)	25	(25.3)	65	(24.6)	143	(17.1)	77	(19.0)	220	(17.7)
Unknown	3	(5.6)	1	(3.3)	4	(4.8)	7	(4.2)	4	(4.0)	11	(4.2)	50	(6.0)	14	(3.5)	64	(5.1)

Age at death (years)	50 ~ 59						60 ~ 69
Sex and number	Male		Female		Total		Male		Female		Total
Causes of death	2639	(100.0%)	1118	(100.0%)	3757	(100.0%)	9447	(100.0%)	3471	(100.0%)	12,918	(100.0%)
Vascular diseases	319	(12.1)	101	(9.0)	420	(11.2)	933	(9.9)	321	(9.2)	1254	(9.7)
Chronic renal failure	34	(1.3)	10	(0.9)	44	(1.2)	148	(1.6)	70	(2.0)	218	(1.7)
Diabetic nephropathy	28	(1.1)	9	(0.8)	37	(1.0)	118	(1.2)	59	(1.7)	177	(1.4)
Non-diabetic nephropathy	6	(0.2)	1	(0.1)	7	(0.2)	30	(0.3)	11	(0.3)	41	(0.3)
Ischemic heart diseases	114	(4.3)	33	(3.0)	147	(3.9)	333	(3.5)	97	(2.8)	430	(3.3)
Myocardial infarction	111	(4.2)	32	(2.9)	143	(3.8)	318	(3.4)	96	(2.8)	414	(3.2)
Angina pectoris	3	(0.1)	1	(0.1)	4	(0.1)	15	(0.2)	1	(0.0)	16	(0.1)
Cerebrovascular diseases	171	(6.5)	58	(5.2)	229	(6.1)	452	(4.8)	154	(4.4)	606	(4.7)
Hemorrhage	117	(4.4)	32	(2.9)	149	(4.0)	246	(2.6)	62	(1.8)	308	(2.4)
Infarction	28	(1.1)	14	(1.3)	42	(1.1)	136	(1.4)	38	(1.1)	174	(1.3)
Subarachnoidal hemorrhage	11	(0.4)	9	(0.8)	20	(0.5)	28	(0.3)	36	(1.0)	64	(0.5)
Others	15	(0.6)	3	(0.3)	18	(0.5)	42	(0.4)	18	(0.5)	60	(0.5)
Heart diseases (other than ischemic heart diseases)	181	(6.9)	69	(6.2)	250	(6.7)	558	(5.9)	203	(5.8)	761	(5.9)
Arrhythmia	28	(1.1)	10	(0.9)	38	(1.0)	106	(1.1)	29	(0.8)	135	(1.0)
Heart failure	88	(3.3)	36	(3.2)	124	(3.3)	302	(3.2)	119	(3.4)	421	(3.3)
Others	65	(2.5)	23	(2.1)	88	(2.3)	150	(1.6)	55	(1.6)	205	(1.6)
Diabetic coma	11	(0.4)	3	(0.3)	14	(0.4)	13	(0.1)	3	(0.1)	16	(0.1)
Hypoglycemic coma	4	(0.2)	3	(0.3)	7	(0.2)	7	(0.1)	4	(0.1)	11	(0.1)
Malignant neoplasia	1228	(46.5)	576	(51.5)	1804	(48.0)	4904	(51.9)	1776	(51.2)	6680	(51.7)
Esophagus	30	(1.1)	8	(0.7)	38	(1.0)	182	(1.9)	16	(0.5)	198	(1.5)
Stomach	77	(2.9)	24	(2.1)	101	(2.7)	398	(4.2)	88	(2.5)	486	(3.8)
Lung	215	(8.1)	45	(4.0)	260	(6.9)	1162	(12.3)	189	(5.4)	1351	(10.5)
Colon	108	(4.1)	54	(4.8)	162	(4.3)	369	(3.9)	135	(3.9)	504	(3.9)
Liver	155	(5.9)	23	(2.1)	178	(4.7)	568	(6.0)	127	(3.7)	695	(5.4)
Pancreas	244	(9.2)	84	(7.5)	328	(8.7)	796	(8.4)	352	(10.1)	1148	(8.9)
Uterus	0	(0.0)	54	(4.8)	54	(1.4)	1	(0.0)	113	(3.3)	114	(0.9)
Breast	1	(0.0)	95	(8.5)	96	(2.6)	1	(0.0)	174	(5.0)	175	(1.4)
Leukemia/Lymphoma	154	(5.8)	54	(4.8)	208	(5.5)	403	(4.3)	155	(4.5)	558	(4.3)
Others	244	(9.2)	135	(12.1)	379	(10.1)	1024	(10.8)	427	(12.3)	1451	(11.2)
Infectious diseases	242	(9.2)	120	(10.7)	362	(9.6)	1018	(10.8)	357	(10.3)	1375	(10.6)
Tuberculosis	2	(0.1)	0	(0.0)	2	(0.1)	1	(0.0)	3	(0.1)	4	(0.0)
Pneumonia	109	(4.1)	46	(4.1)	155	(4.1)	580	(6.1)	152	(4.4)	732	(5.7)
Others	131	(5.0)	74	(6.6)	205	(5.5)	437	(4.6)	202	(5.8)	639	(4.9)
Liver cirrhosis	126	(4.8)	44	(3.9)	170	(4.5)	298	(3.2)	117	(3.4)	415	(3.2)
Type B	5	(0.2)	1	(0.1)	6	(0.2)	14	(0.1)	9	(0.3)	23	(0.2)
Type C	29	(1.1)	8	(0.7)	37	(1.0)	83	(0.9)	26	(0.7)	109	(0.8)
NAFLD	9	(0.3)	3	(0.3)	12	(0.3)	26	(0.3)	14	(0.4)	40	(0.3)
Others	83	(3.1)	32	(2.9)	115	(3.1)	175	(1.9)	68	(2.0)	243	(1.9)
Suicide	19	(0.7)	5	(0.4)	24	(0.6)	20	(0.2)	8	(0.2)	28	(0.2)
Others	399	(15.1)	156	(14.0)	555	(14.8)	1374	(14.5)	583	(16.8)	1957	(15.1)
Unknown	110	(4.2)	41	(3.7)	151	(4.0)	322	(3.4)	99	(2.9)	421	(3.3)

Age at death (years)	70 ~						All age				Total
Sex and number	Male		Female		Total		Male		Female
Causes of death	(100.0%)	32,468	(100.0%)	17,749	(100.0%)	50,217	(100.0%)	45,653	(100.0%)	22,902	(100.0%)	68,555	(100.0%)
Vascular diseases	(9.7)	3293	(10.1)	2292	(12.9)	5585	(11.1)	4716	(10.3)	2773	(12.1)	7489	(10.9)
Chronic renal failure	(1.7)	750	(2.3)	531	(3.0)	1281	(2.6)	949	(2.1)	620	(2.7)	1569	(2.3)
Diabetic nephropathy	(1.4)	517	(1.6)	344	(1.9)	861	(1.7)	674	(1.5)	417	(1.8)	1091	(1.6)
Non-diabetic nephropathy	(0.3)	233	(0.7)	187	(1.1)	420	(0.8)	275	(0.6)	203	(0.9)	478	(0.7)
Ischemic heart diseases	(3.3)	1073	(3.3)	652	(3.7)	1725	(3.4)	1585	(3.5)	793	(3.5)	2378	(3.5)
Myocardial infarction	(3.2)	1014	(3.1)	632	(3.6)	1646	(3.3)	1508	(3.3)	771	(3.4)	2279	(3.3)
Angina pectoris	(0.1)	59	(0.2)	20	(0.1)	79	(0.2)	77	(0.2)	22	(0.1)	99	(0.1)
Cerebrovascular diseases	(4.7)	1470	(4.5)	1109	(6.2)	2579	(5.1)	2182	(4.8)	1360	(5.9)	3542	(5.2)
Hemorrhage	(2.4)	558	(1.7)	331	(1.9)	889	(1.8)	974	(2.1)	445	(1.9)	1419	(2.1)
Infarction	(1.3)	613	(1.9)	533	(3.0)	1146	(2.3)	793	(1.7)	595	(2.6)	1388	(2.0)
Subarachnoidal hemorrhage	(0.5)	104	(0.3)	113	(0.6)	217	(0.4)	157	(0.3)	161	(0.7)	318	(0.5)
Others	(0.5)	195	(0.6)	132	(0.7)	327	(0.7)	258	(0.6)	159	(0.7)	417	(0.6)
Heart diseases (other than ischemic heart diseases)	(5.9)	2807	(8.6)	2227	(12.5)	5034	(10.0)	3640	(8.0)	2536	(11.1)	6176	(9.0)
Arrhythmia	(1.0)	259	(0.8)	129	(0.7)	388	(0.8)	414	(0.9)	171	(0.7)	585	(0.9)
Heart failure	(3.3)	1925	(5.9)	1616	(9.1)	3541	(7.1)	2346	(5.1)	1787	(7.8)	4133	(6.0)
Others	(1.6)	623	(1.9)	482	(2.7)	1105	(2.2)	880	(1.9)	578	(2.5)	1458	(2.1)
Diabetic coma	(0.1)	52	(0.2)	84	(0.5)	136	(0.3)	94	(0.2)	96	(0.4)	190	(0.3)
Hypoglycemic coma	(0.1)	41	(0.1)	28	(0.2)	69	(0.1)	54	(0.1)	36	(0.2)	90	(0.1)
Malignant neoplasia	(51.7)	12,041	(37.1)	5529	(31.2)	17,570	(35.0)	18,528	(40.6)	8116	(35.4)	26,644	(38.9)
Esophagus	(1.5)	370	(1.1)	51	(0.3)	421	(0.8)	585	(1.3)	77	(0.3)	662	(1.0)
Stomach	(3.8)	1021	(3.1)	377	(2.1)	1398	(2.8)	1509	(3.3)	499	(2.2)	2008	(2.9)
Lung	(10.5)	2950	(9.1)	709	(4.0)	3659	(7.3)	4362	(9.6)	952	(4.2)	5314	(7.8)
Colon	(3.9)	876	(2.7)	446	(2.5)	1322	(2.6)	1380	(3.0)	640	(2.8)	2020	(2.9)
Liver	(5.4)	1369	(4.2)	581	(3.3)	1950	(3.9)	2109	(4.6)	733	(3.2)	2842	(4.1)
Pancreas	(8.9)	1675	(5.2)	1190	(6.7)	2865	(5.7)	2784	(6.1)	1650	(7.2)	4434	(6.5)
Uterus	(0.9)	1	(0.0)	153	(0.9)	154	(0.3)	2	(0.0)	361	(1.6)	363	(0.5)
Breast	(1.4)	11	(0.0)	250	(1.4)	261	(0.5)	13	(0.0)	557	(2.4)	570	(0.8)
Leukemia/Lymphoma	(4.3)	1035	(3.2)	521	(2.9)	1556	(3.1)	1709	(3.7)	779	(3.4)	2488	(3.6)
Others	(11.2)	2733	(8.4)	1251	(7.0)	3984	(7.9)	4075	(8.9)	1868	(8.2)	5943	(8.7)
Infectious diseases	(10.6)	6549	(20.2)	3166	(17.8)	9715	(19.3)	7933	(17.4)	3695	(16.1)	11,628	(17.0)
Tuberculosis	(0.0)	53	(0.2)	36	(0.2)	89	(0.2)	56	(0.1)	39	(0.2)	95	(0.1)
Pneumonia	(5.7)	4860	(15.0)	1997	(11.3)	6857	(13.7)	5604	(12.3)	2215	(9.7)	7819	(11.4)
Others	(4.9)	1636	(5.0)	1133	(6.4)	2769	(5.5)	2273	(5.0)	1441	(6.3)	3714	(5.4)
Liver cirrhosis	(3.2)	435	(1.3)	353	(2.0)	788	(1.6)	915	(2.0)	537	(2.3)	1452	(2.1)
Type B	(0.2)	32	(0.1)	22	(0.1)	54	(0.1)	55	(0.1)	34	(0.1)	89	(0.1)
Type C	(0.8)	133	(0.4)	138	(0.8)	271	(0.5)	252	(0.6)	173	(0.8)	425	(0.6)
NAFLD	(0.3)	38	(0.1)	56	(0.3)	94	(0.2)	80	(0.2)	73	(0.3)	153	(0.2)
Others	(1.9)	232	(0.7)	137	(0.8)	369	(0.7)	528	(1.2)	257	(1.1)	785	(1.1)
Suicide	(0.2)	43	(0.1)	14	(0.1)	57	(0.1)	96	(0.2)	36	(0.2)	132	(0.2)
Others	(15.1)	6061	(18.7)	3453	(19.5)	9514	(18.9)	8039	(17.6)	4314	(18.8)	12,353	(18.0)
Unknown	(3.3)	1146	(3.5)	603	(3.4)	1749	(3.5)	1638	(3.6)	763	(3.3)	2401	(3.5)

Malignant neoplasms were the most frequent cause of death in each age group, accounting for approximately half of the deaths in patients in their 50s and 60s. The proportion of deaths from pancreatic cancer was high in relatively younger patients in their 30–50s. The proportion of deaths from infectious diseases was highest at 19.3% in patients aged 70 years or older, while in patients in their 30s, it was 15.2%, which was also higher than in other age groups. The proportions of deaths from vascular diseases did not greatly differ among age groups; however, in patients in their 40s and 50s, proportions were 15.2% and 11.2%, respectively, exceeding those of infectious diseases. Among vascular diseases, the proportions of deaths from cerebrovascular diseases were high in all age groups. In patients in their 30s, 40s, and 50s, the proportions reached 7.6%, 8.0%, and 6.1%, respectively, possibly attributable to the high proportion of deaths from cerebral hemorrhage. Conversely, the proportion of deaths from cerebral infarction was the highest in patients aged 70 years or older. The proportion of deaths from ischemic heart diseases in patients in their 40s was 5.6%, which was higher than the proportions in other age groups. The proportion of deaths from chronic renal failure was the highest at 2.6% in patients aged 70 years or older, followed by patients in their 30s at 1.9%. The proportion of deaths from heart failure as a heart disease separate from ischemic heart disease was the highest at 7.1% in patients aged 70 years or older; it was as high as 4.2% even in patients in their 30s.

Comparison of the causes of death between patients with and without diabetes according to age group

In patients with diabetes, the proportions of deaths from malignant neoplasms according to age group were almost the same as those in patients without diabetes. However, compared to patients without diabetes (Table 4), those proportions were slightly lower in patients with diabetes in their 30s to 60s and slightly higher in patients aged 70 years or older with diabetes. Although the proportions of deaths from lung cancer in patients with diabetes were similar to those in patients without diabetes, those from pancreatic cancer in patients with diabetes were markedly higher in all age groups than those in patients without diabetes; similarly, those from liver cancer were higher in patients aged 50 years or older with diabetes. The proportions of deaths from infectious diseases were higher in patients with diabetes than in patients without diabetes in all age groups; meanwhile, proportions in patients in their 50s or younger with diabetes were 2 to 3 times higher than those in patients without diabetes. Although the overall proportions of deaths from vascular diseases in patients with diabetes according to age group were similar to those in patients without diabetes, the proportions of deaths from chronic renal failure in patients with diabetes were markedly higher in all age groups. The proportions of deaths from ischemic heart diseases in patients with diabetes were also higher in all age groups than those in patients without diabetes, with the largest difference noted among patients in their 40s. Meanwhile, the proportions of deaths from cerebrovascular diseases in patients with diabetes were lower in all age groups than those in patients without diabetes. However, the proportions of deaths from cerebral hemorrhage and cerebral infarction in patients in their 40s or younger with diabetes were higher than those in patients without diabetes, whereas those from subarachnoid hemorrhage in patients with diabetes were markedly lower in all age groups than those in patients without diabetes. The proportions of deaths from heart failure as a heart disease separate from ischemic heart diseases in patients with diabetes were higher in all age groups than those in patients without diabetes; the largest difference was between patients in their 30s.

Table 4.

Causes of death at specified ages in Japanese non-diabetic subjects

Age at death (years)	0～9						10～19
Sex and number	Male		Female		Total		Male		Female		Total
Causes of death	801	(100.0%)	642	(100.0%)	1443	(100.0%)	391	(100.0%)	224	(100.0%)	615	(100.0%)
Vascular diseases	28	(3.5)	10	(1.6)	38	(2.6)	18	(4.6)	15	(6.7)	33	(5.4)
Chronic renal failure	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	1	(0.4)	1	(0.2)
Diabetic nephropathy
Non-diabetic nephropathy
Ischemic heart diseases	2	(0.2)	1	(0.2)	3	(0.2)	1	(0.3)	0	(0.0)	1	(0.2)
Myocardial infarction	2	(0.2)	1	(0.2)	3	(0.2)	1	(0.3)	0	(0.0)	1	(0.2)
Angina pectoris	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Cerebrovascular diseases	25	(3.1)	9	(1.4)	34	(2.4)	17	(4.3)	14	(6.3)	31	(5.0)
Hemorrhage	11	(1.4)	4	(0.6)	15	(1.0)	4	(1.0)	5	(2.2)	9	(1.5)
Infarction	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	2	(0.9)	2	(0.3)
Subarachnoidal hemorrhage	0	(0.0)	0	(0.0)	0	(0.0)	5	(1.3)	1	(0.4)	6	(1.0)
Others	13	(1.6)	5	(0.8)	18	(1.2)	8	(2.0)	6	(2.7)	14	(2.3)
Heart diseases (other than ischemic heart diseases)	80	(10.0)	91	(14.2)	171	(11.9)	24	(6.1)	14	(6.3)	38	(6.2)
Arrythmia	3	(0.4)	5	(0.8)	8	(0.6)	4	(1.0)	2	(0.9)	6	(1.0)
Heart failure	22	(2.7)	27	(4.2)	49	(3.4)	9	(2.3)	7	(3.1)	16	(2.6)
Others	55	(6.9)	59	(9.2)	114	(7.9)	11	(2.8)	5	(2.2)	16	(2.6)
Diabetic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Hypoglycemic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Malignant neoplasia	61	(7.6)	53	(8.3)	114	(7.9)	90	(23.0)	49	(21.9)	139	(22.6)
Esophagus	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	0	(0.0)	0	(0.0)
Stomach	0	(0.0)	1	(0.2)	1	(0.1)	0	(0.0)	1	(0.4)	1	(0.2)
Lung	1	(0.1)	1	(0.2)	2	(0.1)	1	(0.3)	1	(0.4)	2	(0.3)
Colon	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	0	(0.0)	0	(0.0)
Liver	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	1	(0.4)	1	(0.2)
Pancreas	0	(0.0)	1	(0.2)	1	(0.1)	0	(0.0)	0	(0.0)	0	(0.0)
Uterus	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	1	(0.4)	1	(0.2)
Breast	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Leukemia/Lymphoma	24	(3.0)	23	(3.6)	47	(3.3)	35	(9.0)	20	(8.9)	55	(8.9)
Others	33	(4.1)	27	(4.2)	60	(4.2)	54	(13.8)	25	(11.2)	79	(12.8)
Infectious diseases	70	(8.7)	39	(6.1)	109	(7.6)	21	(5.4)	12	(5.4)	33	(5.4)
Tuberculosis	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Pneumonia	20	(2.5)	16	(2.5)	36	(2.5)	8	(2.0)	6	(2.7)	14	(2.3)
Others	50	(6.2)	23	(3.6)	73	(5.1)	13	(3.3)	6	(2.7)	19	(3.1)
Liver cirrhosis	7	(0.9)	3	(0.5)	10	(0.7)	1	(0.3)	2	(0.9)	3	(0.5)
Type B	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Type C	1	(0.1)	0	(0.0)	1	(0.1)	0	(0.0)	0	(0.0)	0	(0.0)
NAFLD	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Others	6	(0.7)	3	(0.5)	9	(0.6)	1	(0.3)	2	(0.9)	3	(0.5)
Suicide	0	(0.0)	0	(0.0)	0	(0.0)	40	(10.2)	29	(12.9)	69	(11.2)
Others	486	(60.7)	390	(60.7)	876	(60.7)	167	(42.7)	89	(39.7)	256	(41.6)
Unknown	69	(8.6)	56	(8.7)	125	(8.7)	30	(7.7)	14	(6.3)	44	(7.2)

Age at death (years)	20～29						30～39						40～49
Sex and number	Male		Female		Total		Male		Female		Total		Male		Female		Total
Causes of death	661	(100.0%)	408	(100.0%)	1069	(100.0%)	1208	(100.0%)	934	(100.0%)	2142	(100.0%)	3164	(100.0%)	2422	(100.0%)	5586	(100.0%)
Vascular diseases	37	(5.6)	30	(7.4)	67	(6.3)	155	(12.8)	72	(7.7)	227	(10.6)	552	(17.4)	247	(10.2)	799	(14.3)
Chronic renal failure	2	(0.3)	0	(0.0)	2	(0.2)	5	(0.4)	1	(0.1)	6	(0.3)	8	(0.3)	4	(0.2)	12	(0.2)
Diabetic nephropathy
Non-diabetic nephropathy
Ischemic heart diseases	1	(0.2)	1	(0.2)	2	(0.2)	29	(2.4)	4	(0.4)	33	(1.5)	125	(4.0)	24	(1.0)	149	(2.7)
Myocardial infarction	1	(0.2)	1	(0.2)	2	(0.2)	27	(2.2)	4	(0.4)	31	(1.4)	118	(3.7)	24	(1.0)	142	(2.5)
Angina pectoris	0	(0.0)	0	(0.0)	0	(0.0)	2	(0.2)	0	(0.0)	2	(0.1)	7	(0.2)	0	(0.0)	7	(0.1)
Cerebrovascular diseases	34	(5.1)	29	(7.1)	63	(5.9)	121	(10.0)	67	(7.2)	188	(8.8)	419	(13.2)	219	(9.0)	638	(11.4)
Hemorrhage	6	(0.9)	15	(3.7)	21	(2.0)	56	(4.6)	20	(2.1)	76	(3.5)	154	(4.9)	71	(2.9)	225	(4.0)
Infarction	2	(0.3)	3	(0.7)	5	(0.5)	10	(0.8)	4	(0.4)	14	(0.7)	28	(0.9)	9	(0.4)	37	(0.7)
Subarachnoidal hemorrhage	6	(0.9)	5	(1.2)	11	(1.0)	38	(3.1)	30	(3.2)	68	(3.2)	184	(5.8)	119	(4.9)	303	(5.4)
Others	20	(3.0)	6	(1.5)	26	(2.4)	17	(1.4)	13	(1.4)	30	(1.4)	53	(1.7)	20	(0.8)	73	(1.3)
Heart diseases (other than ischemic heart diseases)	60	(9.1)	22	(5.4)	82	(7.7)	90	(7.5)	38	(4.1)	128	(6.0)	220	(7.0)	94	(3.9)	314	(5.6)
Arrythmia	21	(3.2)	4	(1.0)	25	(2.3)	23	(1.9)	10	(1.1)	33	(1.5)	39	(1.2)	14	(0.6)	53	(0.9)
Heart failure	17	(2.6)	9	(2.2)	26	(2.4)	21	(1.7)	14	(1.5)	35	(1.6)	62	(2.0)	38	(1.6)	100	(1.8)
Others	22	(3.3)	9	(2.2)	31	(2.9)	46	(3.8)	14	(1.5)	60	(2.8)	119	(3.8)	42	(1.7)	161	(2.9)
Diabetic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Hypoglycemic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	2	(0.2)	2	(0.1)	1	(0.0)	0	(0.0)	1	(0.0)
Malignant neoplasia	113	(17.1)	100	(24.5)	213	(19.9)	266	(22.0)	380	(40.7)	646	(30.2)	975	(30.8)	1262	(52.1)	2237	(40.0)
Esophagus	1	(0.2)	0	(0.0)	1	(0.1)	4	(0.3)	2	(0.2)	6	(0.3)	35	(1.1)	18	(0.7)	53	(0.9)
Stomach	5	(0.8)	7	(1.7)	12	(1.1)	25	(2.1)	37	(4.0)	62	(2.9)	109	(3.4)	99	(4.1)	208	(3.7)
Lung	8	(1.2)	2	(0.5)	10	(0.9)	19	(1.6)	9	(1.0)	28	(1.3)	172	(5.4)	75	(3.1)	247	(4.4)
Colon	3	(0.5)	12	(2.9)	15	(1.4)	28	(2.3)	23	(2.5)	51	(2.4)	104	(3.3)	94	(3.9)	198	(3.5)
Liver	3	(0.5)	2	(0.5)	5	(0.5)	22	(1.8)	7	(0.7)	29	(1.4)	71	(2.2)	22	(0.9)	93	(1.7)
Pancreas	2	(0.3)	0	(0.0)	2	(0.2)	9	(0.7)	7	(0.7)	16	(0.7)	75	(2.4)	42	(1.7)	117	(2.1)
Uterus	0	(0.0)	6	(1.5)	6	(0.6)	0	(0.0)	75	(8.0)	75	(3.5)	1	(0.0)	194	(8.0)	195	(3.5)
Breast	0	(0.0)	3	(0.7)	3	(0.3)	0	(0.0)	75	(8.0)	75	(3.5)	0	(0.0)	294	(12.1)	294	(5.3)
Leukemia/Lymphoma	35	(5.3)	17	(4.2)	52	(4.9)	39	(3.2)	23	(2.5)	62	(2.9)	107	(3.4)	60	(2.5)	167	(3.0)
Others	56	(8.5)	51	(12.5)	107	(10.0)	120	(9.9)	122	(13.1)	242	(11.3)	301	(9.5)	364	(15.0)	665	(11.9)
Infectious diseases	32	(4.8)	17	(4.2)	49	(4.6)	55	(4.6)	44	(4.7)	99	(4.6)	111	(3.5)	84	(3.5)	195	(3.5)
Tuberculosis	0	(0.0)	0	(0.0)	0	(0.0)	2	(0.2)	0	(0.0)	2	(0.1)	1	(0.0)	0	(0.0)	1	(0.0)
Pneumonia	16	(2.4)	10	(2.5)	26	(2.4)	24	(2.0)	21	(2.2)	45	(2.1)	50	(1.6)	37	(1.5)	87	(1.6)
Others	16	(2.4)	7	(1.7)	23	(2.2)	29	(2.4)	23	(2.5)	52	(2.4)	60	(1.9)	47	(1.9)	107	(1.9)
Liver cirrhosis	3	(0.5)	4	(1.0)	7	(0.7)	23	(1.9)	21	(2.2)	44	(2.1)	131	(4.1)	49	(2.0)	180	(3.2)
Type B	0	(0.0)	0	(0.0)	0	(0.0)	1	(0.1)	0	(0.0)	1	(0.0)	11	(0.3)	1	(0.0)	12	(0.2)
Type C	0	(0.0)	0	(0.0)	0	(0.0)	1	(0.1)	0	(0.0)	1	(0.0)	11	(0.3)	5	(0.2)	16	(0.3)
NAFLD	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	1	(0.1)	1	(0.0)	0	(0.0)	1	(0.0)	1	(0.0)
Others	3	(0.5)	4	(1.0)	7	(0.7)	21	(1.7)	20	(2.1)	41	(1.9)	109	(3.4)	42	(1.7)	151	(2.7)
Suicide	116	(17.5)	71	(17.4)	187	(17.5)	126	(10.4)	82	(8.8)	208	(9.7)	146	(4.6)	107	(4.4)	253	(4.5)
Others	255	(38.6)	138	(33.8)	393	(36.8)	375	(31.0)	242	(25.9)	617	(28.8)	784	(24.8)	479	(19.8)	1263	(22.6)
Unknown	45	(6.8)	26	(6.4)	71	(6.6)	118	(9.8)	53	(5.7)	171	(8.0)	244	(7.7)	100	(4.1)	344	(6.2)

Age at death (years)	50～59						60～69
Sex and number	Male		Female		Total		Male		Female		Total
Causes of death	6697	(100.0%)	4442	(100.0%)	11139	(100.0%)	16788	(100.0%)	9051	(100.0%)	25839	(100.0%)
Vascular diseases	950	(14.2)	451	(10.2)	1401	(12.6)	1721	(10.3)	865	(9.6)	2586	(10.0)
Chronic renal failure	20	(0.3)	16	(0.4)	36	(0.3)	100	(0.6)	50	(0.6)	150	(0.6)
Diabetic nephropathy
Non-diabetic nephropathy
Ischemic heart diseases	266	(4.0)	36	(0.8)	302	(2.7)	554	(3.3)	129	(1.4)	683	(2.6)
Myocardial infarction	258	(3.9)	36	(0.8)	294	(2.6)	531	(3.2)	127	(1.4)	658	(2.5)
Angina pectoris	8	(0.1)	0	(0.0)	8	(0.1)	23	(0.1)	2	(0.0)	25	(0.1)
Cerebrovascular diseases	664	(9.9)	399	(9.0)	1063	(9.5)	1067	(6.4)	686	(7.6)	1753	(6.8)
Hemorrhage	334	(5.0)	142	(3.2)	476	(4.3)	480	(2.9)	211	(2.3)	691	(2.7)
Infarction	64	(1.0)	21	(0.5)	85	(0.8)	211	(1.3)	105	(1.2)	316	(1.2)
Subarachnoidal hemorrhage	203	(3.0)	189	(4.3)	392	(3.5)	239	(1.4)	304	(3.4)	543	(2.1)
Others	63	(0.9)	47	(1.1)	110	(1.0)	137	(0.8)	66	(0.7)	203	(0.8)
Heart diseases (other than ischemic heart diseases)	355	(5.3)	135	(3.0)	490	(4.4)	830	(4.9)	368	(4.1)	1198	(4.6)
Arrhythmia	78	(1.2)	12	(0.3)	90	(0.8)	125	(0.7)	47	(0.5)	172	(0.7)
Heart failure	103	(1.5)	65	(1.5)	168	(1.5)	302	(1.8)	165	(1.8)	467	(1.8)
Others	174	(2.6)	58	(1.3)	232	(2.1)	403	(2.4)	156	(1.7)	559	(2.2)
Diabetic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Hypoglycemic coma	3	(0.0)	1	(0.0)	4	(0.0)	1	(0.0)	1	(0.0)	2	(0.0)
Malignant neoplasia	2932	(43.8)	2612	(58.8)	5544	(49.8)	8612	(51.3)	5088	(56.2)	13700	(53.0)
Esophagus	230	(3.4)	46	(1.0)	276	(2.5)	671	(4.0)	99	(1.1)	770	(3.0)
Stomach	339	(5.1)	188	(4.2)	527	(4.7)	1068	(6.4)	476	(5.3)	1544	(6.0)
Lung	579	(8.6)	238	(5.4)	817	(7.3)	1968	(11.7)	689	(7.6)	2657	(10.3)
Colon	333	(5.0)	250	(5.6)	583	(5.2)	853	(5.1)	558	(6.2)	1411	(5.5)
Liver	229	(3.4)	64	(1.4)	293	(2.6)	766	(4.6)	242	(2.7)	1008	(3.9)
Pancreas	233	(3.5)	140	(3.2)	373	(3.3)	636	(3.8)	437	(4.8)	1073	(4.2)
Uterus	2	(0.0)	302	(6.8)	304	(2.7)	2	(0.0)	351	(3.9)	353	(1.4)
Breast	5	(0.1)	512	(11.5)	517	(4.6)	6	(0.0)	645	(7.1)	651	(2.5)
Leukemia/Lymphoma	234	(3.5)	133	(3.0)	367	(3.3)	533	(3.2)	334	(3.7)	867	(3.4)
Others	748	(11.2)	739	(16.6)	1487	(13.3)	2109	(12.6)	1257	(13.9)	3366	(13.0)
Infectious diseases	344	(5.1)	178	(4.0)	522	(4.7)	1302	(7.8)	544	(6.0)	1846	(7.1)
Tuberculosis	6	(0.1)	0	(0.0)	6	(0.1)	17	(0.1)	2	(0.0)	19	(0.1)
Pneumonia	182	(2.7)	103	(2.3)	285	(2.6)	837	(5.0)	301	(3.3)	1138	(4.4)
Others	156	(2.3)	75	(1.7)	231	(2.1)	448	(2.7)	241	(2.7)	689	(2.7)
Liver cirrhosis	282	(4.2)	117	(2.6)	399	(3.6)	374	(2.2)	186	(2.1)	560	(2.2)
Type B	20	(0.3)	2	(0.0)	22	(0.2)	27	(0.2)	11	(0.1)	38	(0.1)
Type C	40	(0.6)	24	(0.5)	64	(0.6)	75	(0.4)	53	(0.6)	128	(0.5)
NAFLD	4	(0.1)	4	(0.1)	8	(0.1)	8	(0.0)	13	(0.1)	21	(0.1)
Others	218	(3.3)	87	(2.0)	305	(2.7)	264	(1.6)	109	(1.2)	373	(1.4)
Suicide	154	(2.3)	116	(2.6)	270	(2.4)	148	(0.9)	107	(1.2)	255	(1.0)
Others	1325	(19.8)	672	(15.1)	1997	(17.9)	3038	(18.1)	1574	(17.4)	4612	(17.8)
Unknown	352	(5.3)	160	(3.6)	512	(4.6)	762	(4.5)	318	(3.5)	1080	(4.2)

Age at death (years)	70～						All age				Total
Sex and number	Male		Female		Total		Male		Female
Causes of death	64307	(100.0%)	52475	(100.0%)	116782	(100.0%)	94017	(100.0%)	70598	(100.0%)	164615	(100.0%)
Vascular diseases	6427	(10.0)	7028	(13.4)	13455	(11.5)	9888	(10.5)	8718	(12.3)	18606	(11.3)
Chronic renal failure	866	(1.3)	684	(1.3)	1550	(1.3)	1002	(1.1)	756	(1.1)	1758	(1.1)
Diabetic nephropathy
Non-diabetic nephropathy
Ischemic heart diseases	1980	(3.1)	1728	(3.3)	3708	(3.2)	2958	(3.1)	1923	(2.7)	4881	(3.0)
Myocardial infarction	1913	(3.0)	1659	(3.2)	3572	(3.1)	2851	(3.0)	1852	(2.6)	4703	(2.9)
Angina pectoris	67	(0.1)	69	(0.1)	136	(0.1)	107	(0.1)	71	(0.1)	178	(0.1)
Cerebrovascular diseases	3581	(5.6)	4616	(8.8)	8197	(7.0)	5928	(6.3)	6039	(8.6)	11967	(7.3)
Hemorrhage	1458	(2.3)	1467	(2.8)	2925	(2.5)	2503	(2.7)	1935	(2.7)	4438	(2.7)
Infarction	1164	(1.8)	1562	(3.0)	2726	(2.3)	1480	(1.6)	1706	(2.4)	3186	(1.9)
Subarachnoidal hemorrhage	430	(0.7)	1155	(2.2)	1585	(1.4)	1105	(1.2)	1803	(2.6)	2908	(1.8)
Others	529	(0.8)	432	(0.8)	961	(0.8)	840	(0.9)	595	(0.8)	1435	(0.9)
Heart diseases (other than ischemic heart diseases)	4976	(7.7)	5683	(10.8)	10659	(9.1)	6635	(7.1)	6445	(9.1)	13080	(7.9)
Arrhythmia	469	(0.7)	402	(0.8)	871	(0.7)	762	(0.8)	496	(0.7)	1258	(0.8)
Heart failure	2912	(4.5)	3539	(6.7)	6451	(5.5)	3448	(3.7)	3864	(5.5)	7312	(4.4)
Others	1595	(2.5)	1742	(3.3)	3337	(2.9)	2425	(2.6)	2085	(3.0)	4510	(2.7)
Diabetic coma	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)	0	(0.0)
Hypoglycemic coma	20	(0.0)	17	(0.0)	37	(0.0)	25	(0.0)	21	(0.0)	46	(0.0)
Malignant neoplasia	21687	(33.7)	14074	(26.8)	35761	(30.6)	34736	(36.9)	23618	(33.5)	58354	(35.4)
Esophagus	976	(1.5)	188	(0.4)	1164	(1.0)	1918	(2.0)	353	(0.5)	2271	(1.4)
Stomach	2758	(4.3)	1360	(2.6)	4118	(3.5)	4304	(4.6)	2169	(3.1)	6473	(3.9)
Lung	5466	(8.5)	2217	(4.2)	7683	(6.6)	8214	(8.7)	3232	(4.6)	11446	(7.0)
Colon	1780	(2.8)	1536	(2.9)	3316	(2.8)	3102	(3.3)	2473	(3.5)	5575	(3.4)
Liver	1902	(3.0)	1028	(2.0)	2930	(2.5)	2994	(3.2)	1366	(1.9)	4360	(2.6)
Pancreas	1336	(2.1)	1458	(2.8)	2794	(2.4)	2291	(2.4)	2085	(3.0)	4376	(2.7)
Uterus	4	(0.0)	511	(1.0)	515	(0.4)	9	(0.0)	1440	(2.0)	1449	(0.9)
Breast	16	(0.0)	654	(1.2)	670	(0.6)	27	(0.0)	2183	(3.1)	2210	(1.3)
Leukemia/Lymphoma	1551	(2.4)	1147	(2.2)	2698	(2.3)	2558	(2.7)	1757	(2.5)	4315	(2.6)
Others	5898	(9.2)	3975	(7.6)	9873	(8.5)	9319	(9.9)	6560	(9.3)	15879	(9.6)
Infectious diseases	12509	(19.5)	8554	(16.3)	21063	(18.0)	14444	(15.4)	9472	(13.4)	23916	(14.5)
Tuberculosis	131	(0.2)	78	(0.1)	209	(0.2)	157	(0.2)	80	(0.1)	237	(0.1)
Pneumonia	10093	(15.7)	6108	(11.6)	16201	(13.9)	11230	(11.9)	6602	(9.4)	17832	(10.8)
Others	2285	(3.6)	2368	(4.5)	4653	(4.0)	3057	(3.3)	2790	(4.0)	5847	(3.6)
Liver cirrhosis	607	(0.9)	602	(1.1)	1209	(1.0)	1428	(1.5)	984	(1.4)	2412	(1.5)
Type B	27	(0.0)	24	(0.0)	51	(0.0)	86	(0.1)	38	(0.1)	124	(0.1)
Type C	212	(0.3)	273	(0.5)	485	(0.4)	340	(0.4)	355	(0.5)	695	(0.4)
NAFLD	22	(0.0)	50	(0.1)	72	(0.1)	34	(0.0)	69	(0.1)	103	(0.1)
Others	346	(0.5)	255	(0.5)	601	(0.5)	968	(1.0)	522	(0.7)	1490	(0.9)
Suicide	258	(0.4)	174	(0.3)	432	(0.4)	988	(1.1)	686	(1.0)	1674	(1.0)
Others	14820	(23.0)	13412	(25.6)	28232	(24.2)	21250	(22.6)	16996	(24.1)	38246	(23.2)
Unknown	3003	(4.7)	2931	(5.6)	5934	(5.1)	4623	(4.9)	3658	(5.2)	8281	(5.0)

Average age at death

Table 5 shows the average age at death from all causes and the average age at death according to the cause of death in patients with and without diabetes. Among the total survey population, the average age at death in patients with diabetes was significantly higher in both men and women than in patients without diabetes despite an average difference of approximately 1 year. The average age at death in patients with diabetes was higher by 1.2 years for malignant neoplasms and lower by 2.9 years for infectious diseases, whereas no significant difference was observed for vascular diseases. Among vascular diseases, the average age at death in patients with diabetes was significantly lower by 3.3 and 2.2 years for chronic renal failure and ischemic heart diseases, respectively. Age at death in patients with diabetes was higher by 1.0 years for cerebrovascular diseases but lower by 0.9 and 2.5 years for cerebral hemorrhage and cerebral infarction, respectively. For subarachnoid hemorrhage, the average age at death was higher by 4 years in patients with diabetes. Furthermore, the average age at death from liver cirrhosis was lower than that from other causes. It was lower than the average age at death from all causes by 5.6 and 7 years in patients with and without diabetes, respectively.

Table 5.

Average age at death in Japanese diabetic and non-diabetic subjects

Average age at death	Male			Female			Total
	Diabetic	Non-diabetic	p-values	Diabetic	Non-diabetic	p-values	Diabetic	Non-diabetic	p-values
Causes of death
Total	74.4 ± 10.7	73.5 ± 15.3	< 0.001	77.4 ± 11.8	76.6 ± 16.4	< 0.001	75.4 ± 11.1	74.8 ± 15.9	< 0.001
Total(except for suicide, others and unknown)	74.2 ± 10.6	74.2 ± 13.5	0.331	77.1 ± 11.6	76.5 ± 15.0	< 0.001	75.2 ± 11.0	75.1 ± 14.2	0.476
Vascular diseases	74.1 ± 11.3	72.9 ± 14.8	< 0.001	79.0 ± 11.3	79.2 ± 13.7	0.432	76.0 ± 11.6	75.9 ± 14.6	0.550
Chronic renal failure	76.7 ± 10.2	80.1 ± 10.6	< 0.001	80.2 ± 10.1	83.0 ± 10.3	< 0.001	78.1 ± 10.3	81.4 ± 10.6	< 0.001
Diabetic nephropathy	76.1 ± 10.0			79.3 ± 9.9			77.3 ± 10.1
Non-diabetic nephropathy	78.3 ± 10.3			82.0 ± 10.1			79.9 ± 10.4
Ischemic heart diseases	73.5 ± 11.2	74.0 ± 13.2	0.153	79.0 ± 10.7	82.9 ± 10.7	< 0.001	75.3 ± 11.3	77.5 ± 13.0	< 0.001
Myocardial infarction	73.4 ± 11.3	74.1 ± 13.1	0.065	78.9 ± 10.8	82.9 ± 10.8	< 0.001	75.2 ± 11.4	77.5 ± 13.0	< 0.001
Angina pectoris	75.9 ± 8.9	72.7 ± 14.1	0.059	80.7 ± 9.8	84.2 ± 7.2	0.076	77.0 ± 9.3	77.3 ± 13.1	0.835
Cerebrovascular diseases	73.5 ± 11.8	71.1 ± 15.7	< 0.001	78.5 ± 12.1	77.6 ± 14.6	0.011	75.4 ± 12.1	74.4 ± 15.5	< 0.001
Hemorrhage	70.8 ± 12.4	70.5 ± 15.1	0.501	75.4 ± 12.6	76.7 ± 14.8	0.056	72.3 ± 12.6	73.2 ± 15.2	0.010
Infarction	76.3 ± 10.0	77.6 ± 11.7	0.006	81.8 ± 10.8	84.1 ± 10.4	< 0.001	78.6 ± 10.7	81.1 ± 11.5	< 0.001
Subarachnoidal hemorrhage	71.8 ± 12.3	64.1 ± 15.6	< 0.001	75.3 ± 10.8	73.0 ± 14.6	0.016	73.6 ± 11.7	69.6 ± 15.6	< 0.001
Others	76.1 ± 11.7	70.5 ± 18.9	< 0.001	78.5 ± 13.3	75.4 ± 17.7	0.016	77.0 ± 12.4	72.5 ± 18.6	< 0.001
Heart diseases (other than ischemic heart diseases)	76.5 ± 11.4	75.6 ± 16.5	< 0.001	81.7 ± 10.9	82.3 ± 15.6	0.017	78.6 ± 11.5	78.9 ± 16.4	0.074
Arrythmia	72.5 ± 11.8	70.4 ± 17.0	0.011	76.8 ± 11.8	78.8 ± 17.0	0.082	73.8 ± 11.9	73.7 ± 17.5	0.461
Heart failure	78.2 ± 10.2	79.7 ± 13.9	< 0.001	83.0 ± 10.1	84.7 ± 13.2	< 0.001	80.2 ± 10.4	82.3 ± 13.8	< 0.001
Others	73.8 ± 13.0	71.5 ± 18.2	< 0.001	79.2 ± 12.1	78.6 ± 18.3	0.340	75.9 ± 12.9	74.8 ± 18.6	0.004
Diabetic coma	67.3 ± 19.1			80.7 ± 14.2			74.1 ± 18.1
Hypoglycemic coma	75.1 ± 11.4	75.6 ± 11.9	0.861	78.8 ± 12.8	81.0 ± 17.1	0.590	76.6 ± 12.0	78.1 ± 14.6	0.534
Malignant neoplasia	72.6 ± 9.7	72.0 ± 12.2	< 0.001	73.8 ± 11.2	71.3 ± 14.3	< 0.001	72.9 ± 10.2	71.7 ± 13.1	< 0.001
Esophagus	72.3 ± 8.4	69.7 ± 9.9	< 0.001	72.7 ± 10.7	70.2 ± 12.2	0.092	72.3 ± 8.7	69.8 ± 10.3	< 0.001
Stomach	73.5 ± 9.1	72.7 ± 11.0	0.007	75.9 ± 10.9	73.0 ± 13.8	< 0.001	74.1 ± 9.7	72.8 ± 12.0	< 0.001
Lung	73.3 ± 8.6	73.3 ± 10.5	0.665	75.6 ± 9.6	74.5 ± 11.7	0.002	73.7 ± 8.8	73.6 ± 10.9	0.189
Colon	72.2 ± 9.6	71.1 ± 11.7	0.002	75.0 ± 10.6	73.0 ± 13.3	< 0.001	73.1 ± 10.0	72.0 ± 12.5	< 0.001
Liver	72.8 ± 9.2	72.6 ± 10.9	0.624	76.2 ± 8.6	75.8 ± 11.0	0.309	73.7 ± 9.2	73.6 ± 11.1	0.429
Pancreas	71.2 ± 9.6	71.3 ± 11.1	0.813	74.6 ± 9.9	74.7 ± 11.3	0.774	72.5 ± 9.9	72.9 ± 11.3	0.026
Uterus	72.5 ± 7.8	66.6 ± 13.3	0.568	66.5 ± 12.6	63.2 ± 14.6	< 0.001	66.5 ± 12.6	63.2 ± 14.5	< 0.001
Breast	75.9 ± 10.2	70.5 ± 9.6	0.109	68.1 ± 11.6	62.8 ± 13.3	< 0.001	68.2 ± 11.7	62.9 ± 13.3	< 0.001
Leukemia/Lymphoma	70.4 ± 12.8	69.9 ± 16.2	0.227	72.4 ± 13.6	71.7 ± 16.5	0.243	71.0 ± 13.1	70.6 ± 16.4	0.118
Others	73.3 ± 10.0	71.9 ± 13.7	< 0.001	73.8 ± 11.4	71.1 ± 15.4	< 0.001	73.5 ± 10.5	71.6 ± 14.4	< 0.001
Infectious diseases	77.9 ± 10.1	80.3 ± 12.1	< 0.001	80.4 ± 10.9	83.4 ± 12.4	< 0.001	78.7 ± 10.4	81.6 ± 12.3	< 0.001
Tuberculosis	81.3 ± 8.0	80.9 ± 12.0	0.783	80.9 ± 7.8	86.7 ± 7.1	< 0.001	81.1 ± 7.9	82.8 ± 10.9	0.056
Pneumonia	79.2 ± 9.3	81.7 ± 10.3	< 0.001	82.1 ± 10.1	84.6 ± 11.2	< 0.001	80.0 ± 9.6	82.8 ± 10.7	< 0.001
Others	74.6 ± 11.1	75.2 ± 16.0	0.090	77.8 ± 11.6	80.5 ± 14.4	< 0.001	75.8 ± 11.4	77.7 ± 15.8	< 0.001
Liver cirrhosis	68.1 ± 10.9	65.8 ± 13.4	< 0.001	72.7 ± 11.1	70.6 ± 14.2	< 0.001	69.8 ± 11.2	67.8 ± 13.9	< 0.001
Type B	69.6 ± 10.7	63.7 ± 12.5	0.005	71.5 ± 9.4	72.6 ± 10.5	0.650	70.3 ± 10.2	66.5 ± 12.6	0.007
Type C	69.6 ± 9.8	71.6 ± 11.4	0.023	75.9 ± 8.5	75.5 ± 9.9	0.654	72.2 ± 9.8	73.6 ± 10.8	0.026
NAFLD	69.2 ± 12.6	72.4 ± 8.4	0.111	76.6 ± 8.8	75.5 ± 11.8	0.527	72.7 ± 11.5	74.5 ± 10.9	< 0.001
Others	67.1 ± 11.0	63.8 ± 13.6	< 0.001	69.5 ± 12.3	66.5 ± 15.8	0.003	67.9 ± 11.5	64.7 ± 14.5	< 0.001
Suicide	64.9 ± 13.6	53.2 ± 20.4	< 0.001	63.1 ± 17.0	53.9 ± 20.3	0.010	64.4 ± 14.5	53.5 ± 20.4	< 0.001
Others	75.4 ± 10.9	72.6 ± 18.6	< 0.001	78.3 ± 12.3	77.3 ± 18.9	< 0.001	76.5 ± 11.5	74.7 ± 18.9	< 0.001
Unknown	74.1 ± 11.4	71.8 ± 17.9	< 0.001	77.9 ± 11.9	78.4 ± 17.5	0.315	75.3 ± 11.7	74.7 ± 18.0	0.036

Glycemic control status and average age at death

Table 6 shows the relationship between glycemic control (divided into patients with an HbA1c level [NGSP] < 8.4% and those with a level ≥ 8.4%) and the age at death among 37,299 patients with available HbA1c levels. The average age at death from all causes was lower by 1.6 years in patients with poorer (i.e., HbA1c ≥ 8.4%) than better (i.e., HbA1c < 8.4%) glycemic control. For all vascular diseases, no difference existed in the average age at death between patients with poorer and better glycemic control. However, the average age at death from ischemic heart diseases, especially myocardial infarction, and cerebrovascular diseases, especially cerebral hemorrhage, was lower by 4.7 and 4.2 years, respectively, in patients with poorer glycemic control. In addition, the average age at death in patients with poorer glycemic control was lower by 3.7 years for heart diseases other than ischemic heart diseases, 1.6 years for infectious diseases, and 8.2 years for diabetic coma. The average age at death from malignant neoplasms did not significantly differ between patients with poorer and better glycemic control.

Table 6.

Causes of death, average age at death and glycemic control in Japanaese diabetic subjects

Glycemic control	Male			Female			Total
	Better	Poorer	p-values	Better	Poorer	p-values	Better	Poorer	p-values
Causes of death	(n = 21,957)	(n = 2908)		(n = 10,890)	(n = 1544)		(n = 32,847)	(n = 4452)
Vascular diseases	72.9 ± 14.8	74.2 ± 11.3	< 0.001	79.2 ± 13.7	79.0 ± 11.3	0.432	75.9 ± 14.6	76.0 ± 11.6	0.550
Chronic renal failure	76.2 ± 10.2	75.6 ± 10.4	0.746	81.1 ± 9.7	78.9 ± 7.8	0.309	78.1 ± 10.3	76.7 ± 9.7	0.296
Diabetic nephropathy	75.9 ± 10.1	74.3 ± 11.1	0.401	80.1 ± 9.7	76.5 ± 7.7	0.167	77.4 ± 10.1	75.0 ± 10.1	0.114
Non-diabetic nephropathy	76.9 ± 10.5	79.3 ± 7.5	0.448	83.0 ± 9.3	84.7 ± 4.7	0.670	79.5 ± 10.5	81.1 ± 7.1	0.527
Ischemic heart diseases	74.0 ± 10.5	67.6 ± 12.9	< 0.001	78.4 ± 10.4	76.8 ± 13.1	0.322	75.5 ± 10.7	70.9 ± 13.7	< 0.001
Myocardial infarction	73.8 ± 10.6	67.7 ± 12.9	< 0.001	78.4 ± 10.5	76.5 ± 13.2	0.242	75.4 ± 10.8	70.7 ± 13.7	< 0.001
Angina pectoris	77.1 ± 8.7	63.0		76.5 ± 8.1	86.0 ± 4.2	0.132	76.9 ± 8.4	78.3 ± 13.6	0.785
Cerebrovascular diseases	73.6 ± 11.3	71.2 ± 13.5	0.034	79.1 ± 11.4	78.1 ± 14.3	0.447	75.7 ± 11.6	73.8 ± 14.2	0.039
Hemorrhage	71.0 ± 12.0	66.3 ± 14.3	0.011	76.1 ± 12.7	74.6 ± 12.5	0.577	72.6 ± 12.4	68.4 ± 14.4	0.008
Infarction	76.2 ± 9.7	74.9 ± 11.9	0.400	82.4 ± 9.9	79.3 ± 13.5	0.122	78.9 ± 10.2	76.8 ± 12.7	0.095
Subarachnoidal hemorrhage	74.1 ± 9.8	70.3 ± 14.6	0.407	75.4 ± 10.1	81.8 ± 8.8	0.222	74.8 ± 10.0	73.2 ± 14.1	0.663
Others	75.7 ± 11.0	75.3 ± 10.9	0.895	79.1 ± 10.5	77.3 ± 20.8	0.631	76.9 ± 10.9	76.4 ± 16.7	0.823
Heart diseases (other than ischemic heart diseases)	76.7 ± 11.0	71.9 ± 13.7	< 0.001	81.4 ± 10.5	78.2 ± 15.3	0.007	78.5 ± 11.0	74.8 ± 14.8	< 0.001
Arrythmia	72.1 ± 12.4	66.2 ± 11.7	0.053	77.4 ± 9.8	75.8 ± 14.4	0.693	73.6 ± 12.0	70.2 ± 13.6	0.140
Heart failure	78.4 ± 9.8	74.3 ± 13.5	< 0.001	82.6 ± 10.1	80.2 ± 14.4	0.085	80.1 ± 10.2	77.1 ± 14.2	0.002
Others	74.2 ± 12.2	68.2 ± 13.6	0.001	79.1 ± 11.1	73.4 ± 17.0	0.035	76.1 ± 12.1	70.5 ± 15.3	< 0.001
Diabetic coma	76.4 ± 16.5	62.4 ± 191	0.012	83.1 ± 15.4	81.0 ± 16.4	0.670	79.6 ± 16.1	71.4 ± 20.1	0.031
Hypoglycemic coma	77.7 ± 9.6	68.7 ± 14.5	0.140	78.6 ± 14.2	78.0 ± 19.8	0.956	78.0 ± 11.3	72.4 ± 15.1	0.306
Malignant neoplasia	72.5 ± 9.6	71.7 ± 10.4	0.015	73.6 ± 11.2	73.7 ± 11.0	0.869	72.9 ± 10.1	72.3 ± 10.6	0.055
Esophagus	71.9 ± 9.0	71.2 ± 8.8	0.651	74.9 ± 10.5	76.3 ± 10.5	0.815	72.2 ± 9.2	71.7 ± 9.0	0.725
Stomach	73.1 ± 8.8	74.3 ± 13.1	0.355	76.4 ± 11.1	69.1 ± 11.3	0.003	73.9 ± 9.5	72.7 ± 12.7	0.296
Lung	73.4 ± 8.4	72.3 ± 9.0	0.027	75.2 ± 9.9	73.0 ± 10.3	0.117	73.7 ± 8.7	72.4 ± 9.2	0.006
Colon	72.1 ± 9.2	71.0 ± 10.7	0.386	74.2 ± 10.6	72.9 ± 11.2	0.513	72.8 ± 9.7	71.5 ± 10.8	0.198
Liver	72.8 ± 9.1	71.1 ± 9.7	0.187	76.4 ± 8.7	77.4 ± 10.6	0.580	73.7 ± 9.2	73.2 ± 10.4	0.664
Pancreas	70.8 ± 9.8	71.0 ± 10.0	0.789	73.9 ± 9.8	75.2 ± 10.2	0.133	72.0 ± 9.9	72.7 ± 10.3	0.223
Uterus		78.0		66.2 ± 12.9	66.6 ± 14.0	0.883	66.2 ± 12.9	67.1 ± 13.9	0.744
Breast	78.4 ± 4.2			67.5 ± 11.6	66.8 ± 8.0	0.741	67.7 ± 11.6	66.8 ± 8.0	0.572
Leukemia/Lymphoma	71.0 ± 12.2	69.7 ± 11.8	0.369	73.2 ± 13.2	74.1 ± 12.2	0.702	71.7 ± 12.6	71.0 ± 12.0	0.598
Others	73.3 ± 10.1	72.6 ± 11.8	0.439	73.9 ± 11.3	75.6 ± 11.1	0.199	73.5 ± 10.5	73.4 ± 11.7	0.942
Infectious diseases	78.0 ± 9.6	75.5 ± 11.9	< 0.001	80.6 ± 10.4	80.6 ± 11.2	0.098	78.9 ± 9.9	77.3 ± 11.9	< 0.001
Tuberculosis	80.4 ± 8.9	85.0		80.7 ± 6.7	91.0 ± 7.0	0.022	80.5 ± 8.1	89.5 ± 6.5	0.034
Pneumonia	79.0 ± 9.0	77.7 ± 10.3	0.027	82.0 ± 9.8	81.7 ± 10.5	0.695	79.9 ± 9.3	78.9 ± 10.5	0.053
Others	75.5 ± 10.7	71.1 ± 13.5	< 0.001	78.3 ± 11.0	79.0 ± 11.9	0.519	76.6 ± 10.9	74.4 ± 13.4	0.009
Liver cirrhosis	68.6 ± 11.0	66.4 ± 13.1	0.262	73.1 ± 10.9	72.8 ± 11.0	0.916	70.2 ± 11.2	69.1 ± 12.6	0.435
Type B	72.1 ± 10.6	72.0 ± 6.3	0.981	71.6 ± 9.1	73.5 ± 6.4	0.784	71.9 ± 9.7	72.5 ± 5.7	0.880
Type C	70.2 ± 9.2	72.7 ± 13.7	0.391	77.1 ± 8.0	72.9 ± 10.7	0.158	72.7 ± 9.4	72.8 ± 12.2	0.993
NAFLD	70.3 ± 13.9	63.3 ± 13.0	0.404	76.1 ± 8.8	77.8 ± 8.9	0.681	73.5 ± 11.7	72.4 ± 12.2	0.789
Others	67.2 ± 11.3	61.8 ± 12.5	0.046	69.2 ± 12.2	70.4 ± 12.9	0.771	67.9 ± 11.6	64.9 ± 13.1	0.191
Suicide	64.3 ± 13.0	56.6 ± 17.6	0.119	67.5 ± 13.1			65.2 ± 13.0	56.6 ± 17.6	0.065
Others	75.6 ± 10.7	73.6 ± 12.0	< 0.001	78.5 ± 12.0	78.3 ± 12.3	0.775	76.6 ± 11.2	75.3 ± 12.3	0.006
Unknown	74.7 ± 10.7	70.7 ± 13.5	< 0.001	77.8 ± 12.1	78.1 ± 10.8	0.851	75.7 ± 11.2	73.3 ± 13.1	0.012
All the causes	74.5 ± 10.4	72.2 ± 12.1	< 0.001	77.3 ± 11.5	77.1 ± 12.5	0.423	75.5 ± 10.9	73.9 ± 12.5	< 0.001

Details of diabetes treatment and death from vascular diseases

Table 7 illustrates that patients who died from vascular diseases had been treated with diet therapy alone (21.7%), oral hypoglycemic therapy (51.8%), or insulin therapy (35.2%). The most administered treatment was the oral hypoglycemic agent, which had also been administered to 51.9% of patients who died from diabetic nephropathy. Insulin therapy was administered to 40.2% of patients who died from diabetic nephropathy, which was higher than 32.4% and 29.7% of patients who died from ischemic heart diseases and cerebrovascular diseases, respectively. The proportion of patients who had received diet therapy alone was slightly lower at 18.8% in patients who died from diabetic nephropathy, whereas 19.4% and 23.5% of patients who died from ischemic heart diseases and cerebrovascular diseases, respectively, received diet therapy alone. The sum of the proportions exceeds 100% because multiple options were marked for patients treated with insulin in combination with oral hypoglycemic agents or glucagon-like peptide-1 receptor agonists.

Table 7.

Treatment of diabetes and vascular diseases as a cause of death in Japanese diabetic subjects

Causes of death	Diabetic nephropathy			Ischemic heart diseases
				Myocardial infarction			Angina pectoris			Total
Treatment	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total
Diet alone	131	74	18.79%	278	168	19.57%	12	3	15.15%	290	171	19.39%
			205			446			15			461
Oral hypoglycemic agents	359	207	51.88%	849	399	54.76%	39	13	52.53%	888	412	54.67%
			566			1248			52			1300
Insulin	260	179	40.24%	482	248	32.03%	29	12	41.41%	511	260	32.42%
			439			730			41			771
GLP-1 receptor agonist	18	8	2.38%	23	7	1.32%	0	0	0.00%	23	7	1.26%
			26			30			0			30
Others	34	22	5.13%	117		8.03%	7	1	8.08%	124	67	8.03%
			56		66	183			8			191
Total	674	417	1091	1508	771	2279	77	22	99	1585	793	2378
			(118.42%)			(115.71%)			(117.17%)			(115.77%)

Causes of death	Cerebrovascular diseases															Others			All
	Hemorrhage			Infarction			Subarachnoidal hemorrhage			Others			Total
Treatment	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total	Male	Female	Total
Diet alone	208	113	22.62%	160	168	23.63%	41	45	27.04%	55	41	23.02%	464	367	23.46%	8585	4785	21.72%	9470	5397	21.69%
			321			328			86			96			831			13,370			14,867
Oral hypoglycemic agents	489	206	48.98%	445	318	54.97%	70	73	44.97%	129		48.92%	1133	672	50.96%	21,787	10,051	51.73%	24,167	11,342	51.80%
			695			763			143		75	204			1805			31,838			35,509
Insulin	314	132	31.43%	233	152	27.74%	39	44	26.10%	91	48	33.33%	677	376	29.73%			35.53%	16,158	7969	35.19%
			446			385			83			139			1053	14,710	7154	21,864			24,127
GLP-1 receptor agonist	8	4	0.85%	10	8	1.30%	2	0	0.63%	3	2	1.20%	23	14	1.04%	469	242	1.16%	533	271	1.17%
			12			18			2			5			37			711			804
Others	77	38	8.10%	64	33	6.99%	17	18	11.01%	16	14	7.19%	174	103	7.82%	2415	1271	5.99%	2747	1463	6.14%
			115			97			35			30			277			3686			4210
Total	974	445	1419	793	595	1388	157	161	318	258	159	417	2182	1360	3542	41,212	20,332	61,544	45,653	22,902	68,555
			(111.98%)			(114.63%)			(109.75%)			(113.67%)			(113.02%)			(116.13%)			(115.99%)

Discussion

The present survey was composed of questions, including mandatory items, almost identical to those used in four prior surveys on diabetes. In the present survey, paper-based questionnaire forms were not used, and patients were enrolled only through the web-based questionnaire. Although the number of participating institutions in the present survey (208 institutions) was smaller than that in the previous survey (241 institutions), more than 68,000 patients with diabetes (an approximately 1.5-fold increase) were enrolled. Further, more than 160,000 patients without diabetes were enrolled. This might be attributed to the fact that almost all medical institutions included in the present survey had introduced an electronic medical record system, which facilitated the extraction and enrollment of patients. Although, many patients were enrolled, few data on the non-mandatory items were provided as in the previous surveys. Other than the causes of and age at death, pathological conditions, of patients with diabetes were not analyzed. Future surveys should consider implementing measures to request data on non-mandatory items for certain patients.

The National Health and Nutrition Survey in 2019 [10] showed that the number of patients with diabetes was 1.8 times greater in men than in women. The Outline of the Report of Vital Statistics in 2020 (Approximate Number) [11] showed that the number of deaths in the Japanese general population was 1.1 times greater in men than in women. However, in the present survey, the number of patients with diabetes was 2 times greater in men (45,653 patients) than in women (22,902 patients), and the number of all enrolled men (139,674 patients) was 1.5 times greater than that of all enrolled women (93,502 patients). Despite the biased male-to-female ratio in the enrolled patients, the results of the present survey generally reflect the causes of and age at death in patients with and without diabetes in the Japanese general population.

In the first and second surveys, the first-ranked cause of death was vascular diseases, followed by malignant neoplasms and then infectious diseases. However, in the third survey, neoplasms and vascular diseases became the first- and second-ranked causes, respectively. In the fourth survey, the resulting second-ranked cause and the third-ranked cause had switched. Consequently, vascular diseases became the third-ranked cause of death. In the present survey, the proportion of deaths from vascular diseases further decreased. Notably, this proportion had decreased to approximately 1/4 in 40 years since the first survey. Low proportions of deaths resulted from diabetic and hypoglycemic comas: 190 and 90 patients, respectively, (in total 280 patients). On average, around two to three patients in Japan likely died each month even at medical institutions specializing in diabetes. If general medical institutions are included, the incidence of such deaths is assumed to increase considerably. This should be considered in future daily clinical practice.

A longitudinal comparison of periodically repeated questionnaire surveys on the causes of death of patients with diabetes with the results of surveys on the causes of death in the Japanese general population may aid in identifying the changes in the pathological conditions of patients with diabetes in Japan. Such comparison is also significant for the development of future directions. As shown in Table 8, the principal causes of death identified by the five surveys, including the present study, were compared with the causes of death in the Japanese general population in the same periods as reported by the Annual Statistical Report of the National Health Condition, published by the Health and Welfare Statistics Association [12–15], and the Outline of the Report of Vital Statistics in 2020 (Approximate Number) [11]. The proportion of deaths from malignant neoplasms in patients with diabetes continued to increase from 25.3%, 29.2%, 34.1%, and 38.3% in the four previous surveys to 38.9% in the present survey. Meanwhile, the proportion of deaths from malignant neoplasms in the Japanese general population increased to 21.6%, 25.9%, and 31.0% every 10 years but decreased slightly to 29.5% in 2010. In 2020, the proportion decreased further to 27.6%, and the difference between patients with diabetes and the Japanese general population increased further to 11.3%. This may suggest the importance of prevention and management of malignant neoplasms as concomitant diseases in patients with diabetes. The breakdown of malignant neoplasms has also been examined since the third survey. The proportion of deaths from lung cancer has hardly changed in the Japanese general population but has been increasing in patients with diabetes. Based on the results of the present survey, the proportion of deaths in patients with diabetes was 1.4 times higher than the proportion in the Japanese general population. Although the decrease and increase in the proportion of deaths from liver and pancreatic cancer, respectively, are common trends in patients with diabetes and the Japanese general population, both proportions are higher in patients with diabetes than in the Japanese general population. In the present survey, the proportions of deaths from liver and pancreatic cancer were 2.3 and 2.4 times higher, respectively. These proportions remained higher than those in a pooled analysis performed with Japanese data by the Committee on Diabetes Mellitus and Cancer [16].

Table 8.

Causes of death in Uapanese general population and diabetic subjects-comparisons between 1971–1980, 1981–1990, 1991–2000, 2001–2010 and 2011–2020

Causes of death	1971 ~ 1980		1981 ~ 1990		1991 ~ 2000		2001 ~ 2010		2011 ~ 2020
	General population[11]	Diabetic subjects[5]	General population[12]	Diabetic subjects[6]	General population[13]	Diabetic subjects[7]	General population[14]	Diabetic subjects[8]	General population[10]	Diabetic subjects
	(n = 695,821)	(n = 9737)	(n = 793,014)	(n = 11,648)	(n = 970,331)	(n = 18,385)	(n = 1,197,066)	(n = 45,708)	(n = 1,372,648)	(n = 68,555)
Vascular diseases	31.7	41.5	24.6	39.3	22.7	26.8	18.8	14.9	14.4	10.9
Chronic renal failure	1.0	12.8	2.0	11.2	1.8	6.8	2.0	3.5	2.0	2.3
Ischemic heart diseases	6.6	12.3	6.4	14.6	7.3	10.2	6.5	4.8	4.9	3.5
Cerebrovascular diseases	24.1	16.4	16.2	13.5	13.6	9.8	10.3	6.6	7.5	5.2
Malignant neoplasia	21.6	25.3	25.9	29.2	31.0	34.1	29.5	38.3	27.6	38.9
Lung					5.6	5.3	5.8	7.0	5.5	7.8
Liver					3.5	8.6	2.7	6.0	1.8	4.1
Pancreas					2.0	4.8	2.3	5.7	2.7	6.5
Infectious diseases	6.2	9.2	8.4	10.2	9.2	14.3	12.1	17.0	10.3	17.0

The decrease in the proportion of deaths from vascular diseases is a common phenomenon in patients with diabetes and the Japanese general population. In the fourth survey, for the first time, the proportion of patients with diabetes was lower than that in the Japanese general population. The present survey showed similar decreases in patients with diabetes and the Japanese general population. Compared to the results of the first survey, these proportions decreased to approximately 1/2 and 1/4 in the Japanese general population and patients with diabetes, respectively, possibly indicating a breakthrough in diabetes treatment.

Among vascular diseases, the proportion of deaths from ischemic heart diseases was substantially higher in patients with diabetes than in the Japanese general population in the first to third surveys, but the proportion of deaths among patients with diabetes was lower than that among the Japanese general population in the fourth survey. The present survey showed a further decrease in ischemic heart diseases as a cause of death to less than 1/4 of the highest proportion observed in the second survey. The decrease in the proportion of deaths from ischemic heart diseases in the entire Japanese population, including patients with diabetes, is presumably attributable to the widespread use of statins and other drugs for lipid control and antihypertensive agents for hypertension control, implementation of screening for ischemic heart diseases by coronary artery computed tomography and other modalities, and advances in interventions. Advances in diabetes management, mainly with antidiabetic agents, may have also contributed to the decrease in the proportion of deaths from ischemic heart diseases in patients with diabetes. Meanwhile, as in the Japanese general population, the proportion of deaths from cerebrovascular diseases in patients with diabetes has been decreasing. This proportion is always lower in patients with diabetes than in the Japanese general population, thus blood pressure and blood lipid levels might be controlled more strictly in patients with diabetes than in the Japanese general population. The proportion of deaths from chronic renal failure has remained almost unchanged at approximately 2.0% for the past 40 years in the Japanese general population; among patients with diabetes, deaths due to chronic failure were at 12.8%, 11.2%, 6.8%, and 3.5% in the previous surveys. In the present survey, it decreased to 2.3%, which was nearly equal to the proportion in the Japanese general population. Possible factors for the marked decrease in the proportion of deaths from chronic renal failure in patients with diabetes include the use of renin-angiotensin system agents, which may have a renoprotective effect, and stricter glycemic control due to advances in diabetes treatment.

The proportion of deaths from infectious diseases, which are the second most frequent cause of death, in patients with diabetes is increasing like in the Japanese general population. In the previous surveys, the proportion of infectious diseases as a cause of death was approximately 1.5 times higher in patients with diabetes. In the present survey, the proportion of patients with diabetes remained unchanged, whereas that in the Japanese general population decreased. Consequently, the differences between them increased. This may suggest the importance of daily clinical practice given the susceptibility to infectious diseases and the likelihood of progression to severe conditions of patients with diabetes.

Table 9 compares the average age at death in patients with diabetes who were enrolled in the five questionnaire surveys—including the present survey—and the average lifespan (17) of the Japanese general population at the time of each survey. The average age at death in patients with diabetes in the present survey was 74.4 years in men and 77.4 years in women. The average lifespan in the Japanese general population in 2020 was 81.6 years in men and 87.7 years in women. The four previous surveys revealed that the average age at death in patients with diabetes was younger than the average lifespan in the Japanese general population; the present survey continued to show this trend. However, in the four previous surveys, the difference between these values decreased from 10.3 to 8.2 years in men and from 13.9 to 11.2 years in women. In the present survey, the difference decreased to 7.2 years in men and 10.3 years in women. Forty years have passed since the first survey, and marked advances in the management and treatment of diabetes during this period have contributed to the improved prognosis of patients with diabetes.

Table 9.

Mean ages at death of Japanese diabetic subjects and life expectancy at birth of Japanese general population-comparison between 1971–1980, 1981–1990, 1991–2000, 2001–2010 and 2011–2020

	1) 1971 ~ 1980		2) 1981 ~ 1990		3) 1991 ~ 2000		4) 2001 ~ 2010		5) 2011 ~ 2020		Differences between 2) and 1)		Differences between 3) and 2)		Differences between 4) and 3)		Differences between5) and 4)
	Male	Femal	Male	Female	Male	Female	Male	Female	Male	Female	Male	Female	Male	Female	Male	Female	Male	Female
A. General population	73.4[16]	78.8[16]	75.9[16]	81.9[16]	77.6[16]	84.6[16]	79.6[16]	86.3[16]	81.6[16]	87.7[16]	+ 2.5	+ 3.1	+ 1.7	+ 2.7	+ 2.0	+ 1.7	+ 2.0	+ 1.4
(life expectancy in years)
B. Diabetic subjects	63.1[5]	64.9[5]	66.5[6]	68.4[6]	68.0[7]	71.6[7]	71.4[8]	75.1[8]	74.4	77.4	+ 3.4	+ 3.5	+ 1.5	+ 3.2	+ 3.4	+ 3.5	+ 3.0	+ 2.2
(mean ages at death)
Differences between A and B	− 10.3	− 13.9	− 9.4	− 13.5	− 9.6	− 13.0	− 8.2	− 11.2	− 7.2	− 10.3
(B-A)

The average age at death in patients with diabetes and the average lifespan in the Japanese general population are described above. Comparing these values is usually problematic. However, the data were compared and analyzed after each previous survey because of the lack of data on the average age at death in the Japanese general population. In the current survey, patients with and without diabetes who were treated at the same institution were enrolled. This allowed a direct comparison of the average age at death between these patients for the first time. The average age at death in patients with diabetes was significantly higher than that in patients without diabetes, albeit with a small difference. According to the principal causes of death, however, the average age at death in patients with diabetes was higher by 1.2 years for malignant neoplasms and lower by 2.9 years for infectious diseases. No significant difference was observed for vascular diseases between patients with and without diabetes. Given the great influence of the proportion of deaths from malignant neoplasms, which was twice that of infectious diseases, the average age at death from all causes appears to have increased in patients with rather than without diabetes. Conversely, among vascular diseases, the average age at death in patients with diabetes was lower by 3.3, 2.2, 0.9, and 2.5 years for chronic renal failure, ischemic heart diseases, cerebral hemorrhage, and cerebral infarction, respectively. This suggests the need for further attention to prevention of the onset and progression of various vascular diseases in future diabetes treatment. In the present survey, the sum of the proportions of deaths from suicide, other causes, and unknown causes was as high as 21.7% in patients with diabetes and 29.2% in patients without diabetes. Many institutions that enrolled patients were acute care hospitals; thus, the present survey may have included a considerable number of young patients who died in accidents and from other causes, consequently possibly affecting the average age at death. Indeed, the average age at death from other causes was 76.5 years in patients with diabetes and 74.7 years in patients without diabetes. The difference between them (1.8 years) was larger than the difference in the average age at death from all causes (0.6 years). In analysis excluding these causes of death, the average age at death was 75.2 years in patients with diabetes (74.2 years in men and 77.1 years in women) and 75.1 years in patients without diabetes (74.2 years in men and 76.5 years in women), showing no significant difference overall (Table 5). Based on data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), the average age at death was 79.3 years in patients with diabetes (77.4 years in men and 82 years in women) and 81.9 years in patients without diabetes (79.3 years in men and 84.4 years in women), showing a difference of approximately 2 years [18]. In a study on the life expectancy of patients with diabetes, the life expectancy of patients aged 40 years with diabetes was 39.2 years in men and 43.6 years in women, while the life expectancy of people aged 40 years in the Japanese general population based on the abridged life table was 39.0 years in men and 45.5 years in women. The difference was negligible [19]. Given these reports and the results of the present study, diabetes does not seem to adversely affect lifetime prognosis. This may ameliorate stigma in patients with diabetes, which has been attracting attention in recent years and includes social stigma, such as the inability to obtain life insurance or a mortgage.

A limitation of the data obtained from questionnaire surveys is the difficulty in standardizing the criteria for determining the causes of death. However, the data obtained from the periodically repeated surveys with nearly the same questions appear to be significant in detecting the changes in the pathological conditions of Japanese patients with diabetes. This data will hopefully be helpful for future daily clinical practice.

It is important to acknowledge as a limitation that while our data quality check was performed thoroughly, there remains the possibility of residual discrepancies in clinical features that may require additional scrutiny.

Declarations

Conflicts of interest

None.