Abstract
Introduction
Cardiovascular disease (CVD) is a common complication and major cause of mortality in people with type 1 diabetes (T1D). This study quantifies the prevalence of CVD among commercially insured adults with T1D in the USA from 2017 to 2021, overall and among age-defined and sex-defined subgroups.
Research design and methods
We used Merative MarketScan nationwide commercial insurance claims database (2017–2021) to identify adults ≥20 years with T1D (International Classification of Diseases, 10th Revision (ICD-10) codes). CVD ascertainment was based on ICD-10 codes for myocardial infarction, atrial fibrillation, ischemic heart disease, heart failure, peripheral artery disease, and stroke. Comorbidities included hypertension, obesity, hyperlipidemia, retinopathy, neuropathy, nephropathy, severe hypoglycemia, and diabetic ketoacidosis. Annual prevalence and age-specific and sex-specific prevalence of CVD were calculated overall and by comorbidities. Logistic regression was used to examine associations between sex, prevalent comorbidities, and odds of CVD.
Results
The sample size ranged from n=21 748 in 2017 to n=13 294 in 2021. Among adults with T1D (mean (SD) age (48.51 (13.95) years in 2017 and 46.80 (13.04) years in 2021; 47% female), the prevalence of CVD ranged from 18.18% (95% CI 17.77 to 18.66%) in 2017 to 20.58% (95% CI 19.91 to 21.24%) in 2021. In 2021, among those aged 20–39 years, 40–64 years, and 65+years, the prevalence of CVD was 4.97%, 20.41%, and 52.94%, respectively. The age-adjusted prevalence of CVD was higher in males than females (21.93% vs 19.07%). Age, sex, and all comorbidities were independently associated with CVD. Odds of CVD were highest among those with hypertension (adjusted OR 3.15, 95% CI: 2.77 to 3.57).
Conclusion
In this sample of US commercially insured adults with T1D, CVD prevalence remained stable at ~20% from 2017 to 2021. Early detection via improved screening and targeted management of comorbidities are key preventive strategies.
Keywords: Diabetes Mellitus, Type 1; Stroke; Peripheral Arterial Disease; Heart Diseases
WHAT IS ALREADY KNOWN ON THIS TOPIC
Cardiovascular disease (CVD), the most common cause of death among individuals with type 1 diabetes (T1D), is associated with hyperglycemia, hypertension, and hyperlipidemia. In the USA, few studies report the prevalence of CVD in people with T1D, particularly among younger adults, as well as the trends and relationship with hypoglycemia.
WHAT THIS STUDY ADDS
From 2017–2021, the prevalence of CVD among commercially insured adults with T1D remained stable at around 20%. CVD prevalence was higher among individuals with a history of severe hypoglycemia and hyperglycemic emergencies along with other comorbidities.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
This study documents the persistent burden of CVD among adults with T1D, highlights the importance of managing comorbidities to reduce CVD risk, and shows the need to further explore the association between comorbidity control and CVD.
Introduction
Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease characterized by the destruction of pancreatic beta cells, leading to absolute insulin deficiency and persistent hyperglycemia. In the USA, approximately 1.3 million individuals live with T1D,1 with prevalence projected to increase due to rising incidence rates and improved life expectancy.2 Despite advancements in the management of T1D, cardiovascular disease (CVD) remains a common complication, affecting about one-quarter of people with T1D.3 Estimates of the cumulative CVD incidence in the USA range from 6.7% over 18 years to 4% over 5 years.4 5 Individuals with T1D face a significantly elevated risk of CVD, up to 7.8 times higher as compared with the general population. 4While international studies suggest declines in CVD incidence among individuals with T1D since the 1990s,6 7 trends in the USA remain unclear.
The effects of CVD on people with T1D extend beyond morbidity. The economic impact of CVD is substantial, with annual healthcare costs nearly tripling for T1D patients with CVD compared with those without CVD.3 In addition, CVD is the leading cause of mortality among people with T1D, accounting for up to 40% of deaths.3 Together, these underscore that CVD in T1D represents a multifaceted burden requiring comprehensive prevention and management strategies.
The development of CVD in T1D is multifactorial, arising from an interplay between traditional and diabetes-specific risk factors. Well-established risk factors for CVD in T1D include aging, hyperglycemia, nephropathy, and other comorbidities such as hypertension and hyperlipidemia.6,11 Longer diabetes duration, which is associated with an increased risk of retinopathy,12 13 is also a known risk factor for CVD.14 15 In addition to the effects of chronic hyperglycemia, recurrent hypoglycemia is associated with preclinical atherosclerosis, a precursor of CVD.16 Some studies report a higher prevalence and incidence of CVD in females with T1D compared with males,5 17 while other studies show the reverse.18 Notably, the relative risk of CVD for females with T1D is higher than the relative risk observed for males.15
Most studies on CVD in T1D are based primarily on data from diabetes specialist registries or selective cohorts. Furthermore, T1D predominantly focuses on two groups – the pediatric population and people in the middle to elderly age range. Despite the earlier onset of CVD in individuals with T1D as compared with those without diabetes,15 there are few studies that include adults under the age of 40 years. Using an insurance claims database to study the prevalence of CVD in T1D allows for inclusion of patients who are outside of the commonly studied groups—those with no access to specialist care and young adults. Understanding CVD, including trends in prevalence, using real-world data is critical to refining prevention strategies and improving clinical guidelines, particularly those related to T1D complications and comorbidities. This study examines the age-specific prevalence of CVD among adults with T1D from 2017 to 2021 using insurance claims data and evaluates sex differences and the role of associated comorbidities in the burden of CVD within this population. We hypothesized that CVD prevalence among adults with T1D in the USA would be stable over time, but higher among older adults and those with other medical conditions.
Research design and methods
This cross-sectional study examined the prevalence and associated risk factors of CVD among US adults with T1D using nationwide insurance claims.
Data source and population
The Merative (formerly Truven) MarketScan Research Database, which contains data on nearly 30 million people with commercial health insurance and captures information across the full continuum of care, was used to create a synthetic cohort of patients with T1D. This database contains deidentified, patient-level data and is one of the largest and longest running proprietary US claims databases used for healthcare research.19 20 This database does not include healthcare data for the unemployed and those who are insured solely through Medicaid and Medicare. We analyzed individual-level data on enrollment, demographics, and clinical diagnosis from the Commercial Claims and Encounters and the Medicare Supplemental Databases, including employees and their dependents enrolled in employer-sponsored health plans. Data were obtained for the period January 1, 2017–December 31, 2021.
Beneficiaries with T1D were identified using International Classification of Diseases, 10th Revision (ICD-10) codes for T1D (E10.xx). Individuals with both T1D and T2D claims were classified as having T1D if their claims included more diagnostic codes for T1D than for T2D (E11.xx). This validated algorithm for identifying T1D has a positive predictive value of 96.4%.21 The same inclusion criteria were applied in each calendar year: in a given year, all beneficiaries aged 20 years and older with a confirmed diagnosis of T1D were included. The number of patients meeting eligibility criteria fluctuated across years depending on the data pooled by Merative MarketScan for that year. Data on age, sex, urban/rural designation, comorbidities, and CVD outcomes were extracted from the database. Comorbidities included cardiovascular risk factors, such as hypertension, obesity, and hyperlipidemia, and complications of T1D such as retinopathy, neuropathy, nephropathy, diabetic ketoacidosis (DKA), and severe hypoglycemia. Information such as duration since onset of diabetes, smoking status, and indices for glycemic control were not available in the database.
CVD outcomes
We used ICD-10 diagnosis codes to classify beneficiaries as having ischemic heart disease (IHD), myocardial infarction (MI), stroke, heart failure (HF), atrial fibrillation, and peripheral arterial disease (PAD) (online supplemental table 1). The use of ICD-10 codes for the identification of certain CVD outcomes has been validated in other studies. The positive predictive value for using these codes was 90–92% for HF,22 92–96% for MI,23 24 and 88–98% for stroke.25 26 A composite CVD outcome was defined as the presence of one or more of the above diagnoses.
Covariates
Demographic information on age, sex, and residence in a rural versus urban area was collected from beneficiary enrollment files. Hypertension, obesity, hyperlipidemia, retinopathy, neuropathy, nephropathy, severe hypoglycemia, and DKA were identified from claims for in-patient and outpatient services using ICD-10 codes (online supplemental table 2).
Statistical analysis
We calculated summary statistics of participant characteristics by year. Age was analyzed as a continuous variable (mean and SD) and as a categorical variable (20–39 years, 40–64 years, and 65 years and older). Frequencies and prevalence of CVD were estimated across categories of sex, urban/rural residence, and comorbidities. Missing values were reported for each variable where applicable.
We, then, estimated the annual prevalence of each CVD component and composite CVD using the number of individuals with T1D in our sample in a given year as the denominator. Age-specific and sex-specific prevalence of CVD and CVD outcomes were also calculated for each year. We conducted a sensitivity analysis using a more conservative CVD definition (requiring two or more ICD-10 codes indicative of CVD to meet case definition); using this more conservative definition, we examined overall CVD prevalence by sex and age.
The direct age-adjusted prevalence of CVD by sex, place of residence, and among those with and without comorbidities and complications for CVD was determined using the total number of people with T1D in each age group category from 2017 to 2021 as the standard population, and the prevalence of CVD outcomes in 2021. The results were reported with 95% CIs.
A multivariable logistic regression model was used to analyze the differences in the prevalence of CVD outcomes among those with and without comorbidities. This model simultaneously adjusted for age, sex, and comorbidities. Cases with missing predictor variables were not included in the logistic regression model. The variance inflation factor (VIF) was used to check for multicollinearity of independent variables in the model. Interactions between CVD, sex and age group were also analyzed.
Data analysis was done using SAS software V.9.4 (Copyright SAS Institute, Cary, North Carolina, USA).
Results
Our study included all individuals with T1D identified in the Merative MarketScan database in each year from 2017 to 2021. The analytic sample across years ranged from n=21 748 in 2017 to n=13 294 in 2021, with fluctuations stemming from the data pooled by Merative MarketScan for a given year. The mean age of individuals included in our analysis was 48.51 (13.95) years in 2017 and 46.80 (13.04) years in 2021. The distribution of females and males was comparable across all years (table 1). For every year, the majority of individuals with T1D were aged 40–64 years and resided in urban areas. Hyperlipidemia and hypertension were the most prevalent comorbidities, while DKA was the least common diabetes-related complication.
Table 1. Sociodemographic and clinical characteristics of commercially-insured adults with T1D in the USA, 2017–2021.
| Years | |||||
|---|---|---|---|---|---|
| 2017 n=21 748 |
2018 n=17 976 |
2019 n=15 568 |
2020 n=14 836 |
2021 n=13 294 |
|
| Age years (mean (SD)) | 48.51 (13.95) | 47.61 (13.26) | 46.52 (12.80) | 47.59 (13.44) | 46.80 (13.04) |
| Age group (%) | |||||
| 20–39 years | 5272 (24.24) | 4484 (24.94) | 4183 (26.87) | 3830 (25.82) | 3600 (27.08) |
| 40–64 years | 13 818 (63.54) | 11 803 (65.66) | 10 283 (66.05) | 9379 (63.22) | 8487 (63.84) |
| 65+ years | 2658 (12.22) | 1689 (9.40) | 1102 (7.08) | 1627 (10.97) | 1207 (9.08) |
| Sex (%) | |||||
| Female | 10 190 (46.85) | 8350 (46.45) | 7324 (47.05) | 6830 (46.04) | 6160 (46.34) |
| Male | 11 558 (53.15) | 9626 (53.55) | 8244 (52.95) | 8006 (53.96) | 7134 (53.66) |
| Residence (%) | |||||
| Rural | 2764 (12.71) | 2219 (12.34) | 918 (5.90) | 1425 (9.61) | 1468 (11.04) |
| Urban | 15 874 (72.99) | 13 195 (73.40) | 11 837 (76.03) | 10 968 (73.93) | 9235 (69.47) |
| Missing | 3110 (14.30) | 2562 (14.25) | 1545 (9.92) | 2443 (16.47) | 2591 (19.49) |
| Comorbidities (%) | |||||
| Obesity | 3177 (14.61) | 2814 (15.65) | 2630 (16.89) | 2499 (16.84) | 2453 (18.45) |
| Hypertension | 11 604 (53.36) | 9181 (51.07) | 7922 (50.98) | 7765 (52.34) | 6959 (52.35) |
| Hyperlipidemia | 12 951 (59.55) | 10 693 (59.48) | 9361 (60.13) | 9099 (61.33) | 8346 (62.78) |
| Retinopathy | 5126 (23.57) | 4213 (23.44) | 3543 (22.76) | 3460 (23.32) | 3347 (25.18) |
| Neuropathy | 4146 (19.06) | 3322 (18.48) | 2755 (17.70) | 2903 (19.57) | 2624 (19.74) |
| Nephropathy | 3439 (15.81) | 2726 (15.16) | 2181 (14.01) | 2469 (16.64) | 2287 (17.20) |
| DKA | 996 (4.58) | 902 (5.02) | 759 (4.88) | 710 (4.79) | 675 (5.08) |
| Hypoglycemia | 2770 (12.74) | 2452 (13.64) | 2276 (14.62) | 2187 (14.74) | 2044 (15.38) |
DKA, diabetic ketoacidosis.
The age-adjusted prevalence of overall CVD increased from 18.18% (n=4219; 95% CI 17.77% to 18.66%) in 2017 to 20.58% (n=3514; 95% CI 19.91% to 21.24%) in 2021 (figure 1; p<0.001). IHD, PAD, and HF were the most prevalent CVD outcomes, with their prevalences also showing an upward trend over the study period.
Figure 1. Trend in cardiovascular disease among commercially insured adults with type 1 diabetes in the USA, 2017–2021. Error bars represent 95%CIs for prevalence.
In 2021, the overall age-specific prevalence of CVD was the highest among the 65 years and older age group (52.94%, n=1207, 95% CI 50.11% to 55.75%), followed by individuals aged 40–64 years (20.41%, n=8487, 95% CI 19.56% to 21.28%), and the lowest among those aged 20–39 years (4.97%, n=3600, 95% CI 4.31% to 5.73%) (figure 2). This pattern was consistent across all individual CVD outcomes and in both sexes (online supplemental table 3). The age-adjusted prevalence of CVD for males and females was 21.93% (n=7134; 95% CI 21.01% to 22.85%) and 19.07 (n=6160; 95% CI 18.11% to 20.02%), respectively. In a sensitivity analysis modifying the outcome definition to require more than one diagnostic code for a CVD outcome to identify those with CVD, the prevalence of CVD disease in both sexes was still highest among the 65 years and older age group, but, as expected, prevalence in each age group decreased (20–39 years old: 2.97% (n=107, 95% CI 2.42% to 3.53%); 40–64 years old: 14.73% (n=1250, 95% CI 13.97% to 15.48%); 65 years and older: 43.25% (n=522, 95% CI 40.45% to 46.04%)) (online supplemental figure 1).
Figure 2. Cardiovascular disease prevalence by age group among commercially insured female and male adults with type 1 diabetes in the USA, 2021. Error bars represent 95% CIs for prevalence.
Based on the 2021 data, the age-adjusted prevalence of CVD was higher in rural (n=1468, 21.13%, 95% CI 19.15% to 23.12%) than in urban areas (n=9289, 19.71%, 95% CI 18.90% to 20.52%). The prevalence of CVD was highest among those with comorbid conditions, particularly neuropathy, nephropathy, and DKA (figure 3). The most common co-occurrence of comorbidities was with hypertension and hyperlipidemia, affecting 1524 people who were identified with CVD (online supplemental figure 2). Logistic regression analysis showed that for each additional year of age beyond 20 years, the odds of CVD increased by 6% (online supplemental table 4). Comorbidities were strongly associated with higher odds of CVD. The highest odds were observed among those with hypertension, nephropathy, and neuropathy. In addition, individuals with hyperlipidemia had 1.59 times higher odds of CVD (95% CI 1.58 to 2.02) compared with those without hyperlipidemia. VIF was approximately 1 for all variables included in the model.
Figure 3. Age-adjusted prevalence of overall cardiovascular disease among those with and without select comorbidities among commercially insured adults with type 1 diabetes mellitus in the USA, 2021. Error bars represent 95% CIs for prevalence. DKA, diabetic ketoacidosis.
The interaction between sex and age group with CVD was significant (p=0.032). Logistic regression after stratification by age group did not show an independent association between sex and CVD in those aged <65 years; however, among those aged 65 years and older, the odds of CVD in males was 1.5 (95% CI 1.17 to 1.93) times higher than in females (table 2).
Table 2. Adjusted ORs for CVD by age group for adults with type 1 diabetes in the USA, 2021.
| Covariate | 20–39 years | 40–64 years | 65+years |
|---|---|---|---|
| Adjusted ORs (95% CIs) | |||
| Sex (Male) | 0.81 (0.59 to 1.12) | 1.10 (0.98 to 1.24) | 1.50 (1.17 to 1.93) |
| Hypertension | 3.27 (2.32 to 4.61) | 3.48 (3.01 to 4.01) | 3.40 (2.38 to 4.89) |
| Obesity | 1.47 (1.03 to 2.10) | 1.34 (1.17 to 1.53) | 1.37 (0.97 to 1.95) |
| Hyperlipidemia | 1.71 (1.21 to 2.41) | 1.89 (1.63 to 2.18) | 1.85 (1.37 to 2.51) |
| Retinopathy | 1.74 (1.22 to 2.49) | 1.30 (1.15 to 1.47) | 1.31 (1.00 to 1.72) |
| Neuropathy | 1.81 (1.20 to 2.71) | 2.12 (1.87 to 2.41) | 1.72 (1.32 to 2.24) |
| Nephropathy | 2.30 (1.56 to 3.39) | 2.09 (1.82 to 2.39) | 2.03 (1.56 to 2.63) |
| Diabetic ketoacidosis | 1.46 (0.87 to 2.44) | 1.36 (1.06 to 1.76) | 2.51 (1.11 to 5.68) |
| Hypoglycemia | 1.26 (0.84 to 1.89) | 1.20 (1.03 to 1.40) | 1.40 (1.00 to 1.96) |
CVD, cardiovascular disease.
Discussion
In this study of commercially insured individuals with T1D in the USA, approximately 20% of adults aged 20 years and older had CVD. The prevalence of CVD increased modestly over the 5-year study period and was higher among older individuals, males, rural residents, and those with comorbid conditions. These findings highlight the substantial and persistent burden of CVD in this population.
Direct comparisons of CVD burden across studies are complicated by methodological differences. In 2021, 21% of individuals with T1D in our study had CVD, slightly lower than the 27% reported by Edelman et al in 2016.3 This discrepancy may reflect differences in classification algorithms for T1D and CVD outcomes. For example, pulmonary embolism was included as a CVD outcome in Edelman et al’s study but not in ours. Other studies, particularly earlier cohort studies, reported lower CVD prevalence (8–10%) due to narrower inclusion criteria, such as younger populations and alternative definitions of CVD (eg, abnormal ECG findings).17 27 In addition to differences in outcome definition, comparisons are further constrained by recent studies quantifying CVD burden using incidence rates. The incidence of CVD is the proportion of new cases of CVD found among an at-risk group in a given period, while prevalence is a proportion of new and existing cases of CVD in a given period. Rawshani et al in their study observed CVD incidence rate of 407/10 000 person-years in 2013.28 In their registry-based study, CVD was defined as the first occurrence of a diagnosis of acute MI or stroke in hospitalized patients with T1D.
The greater prevalence of CVD among adults in rural areas in our study aligns with findings from a recent study on CVD prevalence in the general population in the USA.29 Reduced access to care and an increase in risk factors such as obesity and low socioeconomic status have been attributed to rural-urban disparities in the prevalence and mortality of CVD.29,31
The CVD prevalence in our study increased significantly with age; more than half (53%) of individuals aged 65 years or older had CVD compared with 20% of those aged 40–64 years and 5% of those aged 20–39 years. Our findings complement data from the UK, where CVD prevalence was 13.7% in those with T1D for 20 years or longer and 1% in individuals with T1D for less than 10 years.32 A similar pattern was also observed in the EURODIAB IDDM Complications Study where CVD prevalence was 5% in 15–29 year-olds and 25% in 45–59 year-olds.17 Advancing age and prolonged diabetes duration are well-known risk factors for CVD in T1D, likely due to progressive atherosclerotic- and arteriosclerotic changes in blood vessels.17 33
Males in our study had higher odds and prevalence of CVD compared with females, consistent with findings from the Scottish Care Information–Diabetes Collaboration database.18 This association was significant in the adults aged 65 years and older. Our results contrast with several other reports suggesting that CVD prevalence or incidence is higher in females with T1D. 11 27 34 35This discrepancy may reflect the underdiagnosis of conditions like IHD in women because atypical symptom presentation is more common in women than in men, leading to missed diagnoses, particularly in real-world settings.36 Delayed access to care disproportionately experienced by women and stemming from economic constraints37 may also add to the decreased diagnosis of CVD in women. The higher prevalence of CVD in older males may also be attributable to an accumulation of risk from the lifetime absence of estrogen.38
To our knowledge, this study is the first to examine trends in CVD burden among adults with T1D in the USA over a recent 5-year period. We observed a 13% increase in CVD prevalence from 2017 to 2021. This rise may be attributed to improvements in life expectancy among individuals with T1D due to advances in diabetes management, population aging, and subsequent age-related increase in CVD risk. The high prevalence of comorbidities in our study sample, such as hypertension and hyperlipidemia, likely contributed to this trend. Also, the increasing prevalence may be attributable to diagnostic inflation from upcoding, a situation where billing codes for a disease condition requiring more complex care rather than the actual care is used.39 However, this situation may be true for every year in our review, and the increase in prevalence may be unaffected by a coding inflation. Our findings contrast with a 36% decline in CVD incidence reported in Sweden,28 emphasizing the need for further investigation into the trends in CVD burden among adults with T1D in the USA.
Of all comorbidities examined, hypertension showed the strongest association with the odds of CVD, consistent with its role as a major CVD risk factor. Nearly half of our study population had a diagnosis of hypertension. Nephropathy and neuropathy, both complications of diabetes, were also strongly associated with CVD, mirroring findings from previous studies.5 10 11 Acute glycemic events, indicated by DKA and severe hypoglycemia, were independently associated with CVD, with DKA showing slightly higher odds than severe hypoglycemia. Chronic hyperglycemia promotes vascular inflammation, endothelial dysfunction, and oxidative stress,40 41 while hypoglycemia induces proinflammatory and prothrombotic effects, potentially exacerbating preclinical atherosclerosis.16 Further research is warranted to explore the cumulative impact of acute hyperglycemic events and hypoglycemic events on CVD prevalence in T1D.
This study used a large sample of ~22 000 adults with T1D in the USA, leveraging real-world patient data to provide valuable insights into age-specific CVD and prevalence and temporal trends. To the best of our knowledge, this is the only study to examine the CVD burden in young adults with T1D in the USA.
However, the results of our analyses should also be interpreted with limitations in mind. The findings are generalizable only to commercially insured adults with T1D. Also, adults aged 65 years and older who rely solely on Medicare, the unemployed, and those on Medicaid may be underrepresented. The absence of race and ethnicity data also limits ability to fully understand generalizability. This study may be affected by misclassification bias arising from the use of ICD-10 diagnosis codes alone to define outcomes and comorbidities. Enhanced validation through chart review, lab results, and medication records would improve classification accuracy. However, previous studies have validated the use of ICD-10 codes for identifying CVD conditions such as acute HF, stroke, and MI.22 23 25 42 Asymptomatic and non-hospitalized adults with T1D may also be underrepresented in the insurance claims database as the chance of diagnosis is reduced in this group. Potential confounding from unavailable data such as glycemic, blood pressure, and lipid control; smoking status and diabetes duration limits causal interpretation. However, complications indicative of long-standing diabetes, such as nephropathy and neuropathy, were documented in the claims data. The trend in CVD prevalence should be interpreted with caution as this was not a longitudinal cohort; there were changes in the sample size each year and a possible change in the individuals comprising each sample.
Conclusion
From 2017–2021, the prevalence of CVD among commercially insured adults with T1D remained stable at around 20%. CVD prevalence was higher among individuals with a history of severe hypoglycemia and hyperglycemic emergencies along with other comorbidities.
CVD prevalence was also higher in males than females and increased in a stepwise manner as age increased. All comorbidities showed independent associations with CVD; hypertension, neuropathy, and nephropathy were the most significant contributors. The high occurrence of CVD risk factors such as hypertension and hyperlipidemia is concerning. Early detection via improved screening and targeted management of CVD risk factors may be key preventive strategies.
Further investigation is needed to identify the drivers behind the persistent and age-related prevalence of CVD in T1D. Future studies should leverage linked insurance claims and electronic health records data to improve event validation and examine the effects of patient characteristics such as duration of diabetes and comorbidity control on CVD risk. Additionally, research is warranted to examine the impact of social determinants of health on the occurrence of CVD among people with T1D in the USA. Evaluating the impact of interventions targeting CVD risk factors in this population is essential to inform prevention strategies.
Supplementary material
Footnotes
Funding: This project was supported by the NIH National Center for Advancing Translational Sciences through grant number UL1TR001998 and the University of Kentucky Center for Clinical and Translational Science (CCTS). The content is solely the responsibility of the author and does not necessarily represent the official views of the NIH.
Provenance and peer review: Not commissioned; externally peer reviewed.
Patient consent for publication: Not applicable.
Data availability free text: The data that support the findings of this study are available from Merative Truven MarketScan but restrictions apply to the availability of these data, which were used under license for the current study and so are not publicly available. Data are available from the vendor: https://marketscan.truvenhealth.com/marketscanportal/#
Ethics approval: We used deidentified data for analysis. The University of Kentucky institutional review board (IRB) approved the use of the deidentified database for researchers using only data from the claims database. This database has not been linked with any other database. The Center for Clinical and Translational Sciences Enterprise Data Center approved the IRB protocol number for this data set (43542).
Data availability statement
Data may be obtained from a third party and are not publicly available.
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