Table 5.
HRs for Mortality Outcomes During the Study Period, According to Quartiles of C‐Peptide Levels
| C‐Peptide Category, nmol/L | |||||
|---|---|---|---|---|---|
| Overall | ≤0.418 | 0.419 to 0.652 | 0.653 to 0.983 | ≥0.984 | |
| No. of participants | 5140 | 1284 | 1283 | 1290 | 1283 |
| Cardiovascular mortality, %* | 7.2 | 3.8 | 6.0 | 7.9 | 12.2 |
| Crude HR for cardiovascular mortality (95% CI) | Referent | 1.61 (1.13 to 2.33) | 2.18 (1.40 to 3.28) | 3.44 (2.38 to 5.03) | |
| Adjusted HR for cardiovascular mortality (95% CI) | Referent | 1.20 (0.80 to 1.80) | 1.42 (0.90 to 2.26) | 1.60 (1.07 to 2.39) | |
| No. of participants | 5140 | 1284 | 1283 | 1290 | 1283 |
| Cerebrovascular disease mortality, %* | 1.0 | 0.5 | 0.6 | 0.8 | 2.2 |
| Crude HR for cerebrovascular disease mortality (95% CI) | Referent | 1.33 (0.53 to 3.37) | 1.83 (0.60 to 5.57) | 4.82 (1.81 to 12.8) | |
| Adjusted HR for cerebrovascular disease mortality (95% CI) | Referent | 1.12 (0.44 to 2.83) | 1.22 (0.28 to 5.34) | 3.94 (1.28 to 12.1) | |
| No. of participants | 5140 | 1284 | 1283 | 1290 | 1283 |
| Ischemic heart disease mortality, %* | 3.9 | 2.1 | 3.5 | 4.2 | 6.3 |
| Crude HR for ischemic heart disease mortality (95% CI) | Referent | 1.67 (1.04 to 2.69) | 2.05 (1.30 to 3.26) | 3.15 (2.07 to 4.81) | |
| Adjusted HR for ischemic heart disease mortality (95% CI) | Referent | 1.17 (0.66 to 2.10) | 1.16 (0.65 to 2.06) | 1.22 (0.67 to 2.21) | |
| No. of participants | 5140 | 1284 | 1283 | 1290 | 1283 |
| Myocardial infarction mortality, %* | 1.5 | 1.0 | 1.3 | 1.1 | 2.9 |
| Crude HR for myocardial infarction mortality (95% CI) | Referent | 1.22 (0.59 to 2.51) | 1.13 (0.44 to 2.92) | 3.00 (1.32 to 6.79) | |
| Adjusted HR for myocardial infarction mortality (95% CI) | Referent | 0.79 (0.37 to 1.67) | 0.71 (0.25 to 2.01) | 1.37 (0.66 to 2.83) | |
| No. of participants | 5152 | 1288 | 1287 | 1290 | 1287 |
| Overall mortality, %* | 18.1 | 12.3 | 14.7 | 20.6 | 26.4 |
| Crude HR for overall mortality (95% CI) | Referent | 1.22 (0.94 to 1.57) | 1.77 (1.42 to 2.18) | 2.31 (1.77 to 2.99) | |
| Adjusted HR for overall mortality (95% CI) | Referent | 1.12 (0.88 to 1.43) | 1.57 (1.27 to 1.95) | 1.72 (1.34 to 2.21) | |
ICD‐10 codes were used to define underlying cause of death. Cardiovascular mortality was defined as cardiovascular disease (I00 to I99) being the underlying cause of death or when it was one of the multiple causes of the death (American Heart Association 2011 update on heart disease and stroke).16 Cerebrovascular disease, ischemic heart disease, and myocardial infarction deaths are part of the cardiovascular disease death. Myocardial infarction death is part of the ischemic heart disease death.
Model was adjusted for age, sex, race, waist‐to‐hip ratio, body mass index, blood pressure, total cholesterol, triglycerides, high‐density lipoprotein, history of stroke, heart attack, peripheral arterial disease, family history of diabetes and heart attack, history of chest pain, level of education, smoking status, level of physical activity, alcohol use in last month, C‐reactive protein level, urinary albumin/creatinine ratio, glomerular filtration rate, and glycated hemoglobin levels. Bold values represent statistically significant results at P values of <0.05.
P value <0.01 among quartiles. Mortality rates are population‐weighted averages calculated based on NHANES 3 probability weights rounded to the nearest integer.