Similar cardiovascular risk factor profile in screen-detected and known type 2 diabetic subjects

OBJECTIVE. To compare the cardiovascular disease (CVD) risk factor profile in subjects with screen-detected type 2 diabetes (SDM) and subjects with known type 2 diabetes (KDM). DESIGN. Population-based, cross-sectional survey. SETTING AND SUBJECTS. In a single, semi-rural general practice 2082 subjects were between 20 and 69 years. Of those, 1970 subjects were invited, and a total of 1374 (69.7%) subjects were examined by blood tests, anthropometric measures, and self-administered questionnaires. RESULTS. Before the survey 19 persons were known to have type 2 diabetes. The screening revealed another 31 individuals with type 2 diabetes, diagnosed according to the 1999 World Health Organization criteria. Age, levels of blood pressure, BMI, and dyslipidaemia, and markers of haemostasis and inflammation were comparable in the two groups. Median age in the KDM group was 58 vs. 57 years in the SDM group, p = 0.82, 79% were male vs. 61%, p = 0.23. In both groups 74% had blood pressure ≥ 130/85 mmHg, p = 1.00. In both groups 90% had BMI ≥ 25, p = 1.00, and about half in both groups had BMI ≥ 30, p = 0.56. In the KDM group 63% had dyslipidaemia (low HDL cholesterol or elevated triglycerides) vs. 80% in the SDM group, p = 0.32. Median levels of plasminogen-activator-inhibitor (PAI-1), tissue plasminogen activator (t-PA), as well as fibrinogen and C-reactive protein (CRP) were without statistically significant differences in the two groups, p > 0.1. In contrast, in markers of glycaemic regulation statistically significant differences were found between groups. Median HbA1 was 8.0 vs. 6.5, p < 0.001. Median fasting whole blood glucose level was 8.8 mmol/L vs. 6.3 mmol/L, p < 0.001, and glucose at two hours during OGTT was 16.9 mmol/L vs. 11.2 mmol/L, p < 0.001. Median fasting serum insulin level was 52 pmol/L vs. 80 pmol/L, p = 0.039 and at two hours 127 pmol/L vs. 479 pmol/L, p < 0.001. CONCLUSIONS. The CVD risk-factor profile of SDM patients was similar to the expected adverse profile of patients with KDM. This indicates an already increased risk of cardiovascular disease in diabetic patients before the diabetes becomes clinically manifest, supporting the need for early diagnosis.