Increased Arterial Stiffness in Europeans and African Caribbeans With Type 2 Diabetes Cannot be Accounted for by Conventional Cardiovascular Risk Factors

Background The impact of diabetes on vascular target organ damage (TOD) is not wholly explained by conventional risk factors. African Caribbeans have a greater prevalence of diabetes and some aspects of TOD. We hypothesized that arterial stiffness, an independent cardiovascular risk factor, would be more prevalent with diabetes and in African Caribbeans with diabetes than Europeans. Methods We measured pulse wave velocity (PWV), a measure of arterial stiffness, in the carotid-to-femoral, carotid-to-radial and femoral-to-dorsalis pedis segments, of men and women aged 40 to 65 years from the general population: 49 and 100 Europeans; 66 and 88 African Caribbeans with and without diabetes, respectively. Results Carotid-to-femoral PWV was faster (ie, arteries were stiffer) in diabetes and faster in African Caribbeans with diabetes compared with Europeans. These diabetes differences in PWV persisted after adjustment for conventional cardiovascular risk factors; Europeans without diabetes (95% confidence interval [CI]) 11.8 (11.4–12.3) versus with diabetes 13.3 (12.5–14.1) m/sec, P = .005; African Caribbeans without diabetes 12.6 (12.1–13.2) versus 14.0 (13.2–14.9) m/sec with diabetes, P = .008 (all fully adjusted). The ethnic difference in diabetes was largely attenuated by multivariate adjustment (P = .4). In the carotid-to-radial segment there was no ethnic difference in those without diabetes; however, African Caribbeans with diabetes had significantly faster PWV, which was not observed in Europeans (P for diabetes:ethnicity interaction = .001). Conclusions Elastic arteries are stiffer in diabetes independent of traditional risk factors. African Caribbeans with diabetes have increased stiffness compared to Europeans, predominantly accounted for by blood pressure differences. Muscular arteries respond differently to diabetes in the two ethnic groups, which may reflect differences in remodeling.