High risk of cardiovascular disease in patients with type 1 diabetes in the U.K.: a cohort study using the general practice research database

Abstract

Objective: To estimate the absolute and relative risk of cardiovascular disease (CVD) in patients with type 1 diabetes in the U.K.

Research design and methods: Subjects with type 1 diabetes (n = 7,479) and five age- and sex-matched subjects without diabetes (n = 38,116) and free of CVD at baseline were selected from the General Practice Research Database (GPRD), a large primary care database representative of the U.K. population. Incident major CVD events, comprising myocardial infarction, acute coronary heart disease death, coronary revascularizations, or stroke, were captured for the period 1992-1999.

Results: The hazard ratio (HR) for major CVD was 3.6 (95% CI 2.9-4.5) in type 1 diabetic men compared with those without diabetes and 7.7 (5.5-10.7) in women. Increased HRs were found for acute coronary events (3.0 and 7.6 in type 1 diabetic men and women, respectively, versus nondiabetic subjects), coronary revascularizations (5.0 in men, 16.8 in women), and for stroke (3.7 in men, 4.8 in women). Type 1 diabetic men aged 45-55 years had an absolute CVD risk similar to that of men in the general population 10-15 years older, with an even greater difference in women.

Conclusions: Despite advances in care, these data show that absolute and relative risks of CVD remain extremely high in patients with type 1 diabetes. Women with type 1 diabetes continue to experience greater relative risks of CVD than men compared with those without diabetes.