Complications and cardiovascular risk factors in South Asians and Europeans with early-onset type 2 diabetes

BACKGROUND: Type 2 diabetes is a major cardiovascular risk factor, and early-onset (<40 years) type 2 diabetes is becoming more common. AIM: To determine the prevalence of complications, and cardiovascular risk factors at diagnosis, in early-onset type 2 diabetes, and to compare these between South Asians and Europeans. DESIGN: Prospective study of newly-diagnosed type 2 diabetes patients aged <40 years, attending hospital and primary care clinics 1999-2001. METHODS: Patients were assessed for signs of macrovascular disease, retinopathy, neuropathy and nephropathy. Cardiovascular risk factors were also determined. RESULTS: Overall, 292 patients were enrolled (165 South Asians). Macrovascular disease was more prevalent in South Asians (15.7% vs. 9.4%, p<0.001), as was microvascular disease (27.3% vs. 16.5%, p<0.001), including retinopathy (17.5% vs. 7.9%, p<0.001), and nephropathy (18.1% vs. 7.8%, p<0.001). South Asians had trends towards greater waist:hip ratio (0.95 vs. 0.90), and higher blood pressure (127/80 vs. 123/76 mmHg). HDL cholesterol was lower (1.0 vs. 1.3 mmol/l, p<0.001) and fasting triglycerides higher (1.9 vs. 1.5 mmol/l, p<0.001) in South Asians. Absolute CHD risk was significantly higher in South Asians (16.9% vs. 13.7%, p<0.001). DISCUSSION: Complications were common at diagnosis, with a quarter of all patients having evidence of at least one diabetic complication. South Asians had a higher prevalence of established macrovascular and microvascular disease, compared to Europeans, and a higher risk of CHD, predominantly because of lower HDL cholesterol and higher blood pressure.