Do women exhibit greater differences in established and novel risk factors between diabetes and non-diabetes than men? The British Regional Heart Study and British Women's Heart Health Study

Type 2 diabetes is associated with greater relative risk of CHD in women than in men, which is not fully explained by conventional cardiovascular risk factors. We assessed whether cardiovascular risk factors including more novel factors such as markers of insulin resistance, inflammation, activated coagulation and endothelial dysfunction differ more between diabetic and non-diabetic women than between diabetic and non-diabetic men, and the role of insulin resistance. A cross-sectional study of non-diabetic and diabetic men and women (n = 7,529) aged 60-79 years with no previous myocardial infarction who underwent an examination was conducted. Measurements of anthropometry, blood pressure and fasting measurements of lipids, insulin, glucose and haemostatic and inflammatory markers were taken. Non-diabetic women tended to have more favourable risk factors and were less insulin resistant than non-diabetic men, but this was diminished in the diabetic state. Levels of waist circumference, BMI, von Willebrand factor (VWF), WBC count, insulin resistance (HOMA-IR), diastolic blood pressure, HDL-cholesterol, tissue plasminogen activator (t-PA) and factor VIII differed more between diabetic and non-diabetic women than between diabetic and non-diabetic men (test for diabetes x sex interaction p < 0.05). The more adverse effect of diabetes on these risk markers in women was associated with, and thereby largely attenuated by, insulin resistance. The greater adverse influence of diabetes per se on adiposity and HOMA-IR and downstream blood pressure, lipids, endothelial dysfunction and systemic inflammation in women compared with men may contribute to their greater relative risk of coronary heart disease.