Aim: To assess the determinants and prevalence of hyperlipidaemia in Type 1 diabetic patients in the EURODIAB IDDM Complications Study.
Methods: Standardized questionnaire data were obtained and anthropometric and biochemical measurements performed on 3159 Type 1 diabetic patients, randomly selected from 31 diabetes clinics. Plasma lipid levels were determined centrally, using enzymatic methods
Results: Plasma total cholesterol, high-density lipoprotein cholesterol (HDL-C), and HDL subfractions were higher in women than in men, while plasma triglycerides were higher in men (P < 0.001). Total cholesterol, low-density lipoprotein cholesterol (LDL-C) and HDL-C and HDL-C subfractions were, as expected, significantly associated with age and HbA1c in both sexes. Age and HbA1c adjusted values of triglyceride, total cholesterol, LDL-C, HDL-C and HDL3-C in men and triglyceride and HDL2-C in women showed significant associations with central obesity, measured as the waist to hip ratio (WHR). Current smokers had lipid profiles characteristic of insulin resistance in comparison to nonsmokers. Significant positive associations were observed between hypertension and plasma triglycerides, total cholesterol and LDL-C in men and women. In men, degree of physical activity was negatively associated with triglyceride and positively related to HDL-C and HDL3-C. The prevalence of LDL-hypercholesterolaemia (LDL-C > 3.35 mmol/L) was 45% in men and in women, while plasma triglyceride levels > 1.7 mmol/L were observed in 12% of men and 8% of women.
Conclusion: The results of this study indicate that lipid levels in Type 1 diabetic patients are strongly influenced by smoking habit and central obesity in a way that is characteristic of the insulin resistance syndrome.