The impact of dyslipidaemia on cardiovascular mortality in individuals without a prior history of diabetes in the DECODE Study

Abstract Objective To evaluate the impact of dyslipidaemia on cardiovascular disease (CVD) mortality in relation to fasting (FPG) and 2-h (2hPG) plasma glucose levels in individuals without a prior history of diabetes. Methods Data from 14 European population-based prospective studies of 9132 men and 8631 women aged 25–89 years were jointly analysed. A total of 871 CVD deaths occurred during the average 10 years of follow-up. Subjects were classified into normoglycaemia, isolated fasting hyperglycaemia (IFH, FPG ≥ 6.10 mmol/l and 2hPG < 7.80 mmol/l), isolated post-load hyperglycaemia (IPH, FPG < 6.10 mmol/l and 2hPG ≥ 7.80 mmol/l) and combined fasting and post-load hyperglycaemia (CH, FPG ≥ 6.10 mmol/l and 2hPG ≥ 7.80 mmol/l). Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD mortality were estimated using Cox proportional hazard analysis. Results Multivariate-adjusted HRs (95% CIs) for high-density lipoprotein cholesterol (HDL-C) were 0.84 (0.75–0.94), 0.66 (0.48–0.92), 1.03 (0.84–1.27) and 0.67 (0.51–0.89) in individuals with normoglycaemia, IFH, IPH and CH, respectively. For total cholesterol (TC) to HDL-C ratio they were 1.14 (1.03–1.27), 1.44 (1.13–1.84), 0.94 (0.77–1.15) and 1.26 (1.05–1.50), respectively. HRs for TC and triglycerides (TG) were not significant in most of the glucose categories except for TG in those with CH [HR 1.12 (1.00–1.27)]. Conclusions Low HDL-C and high TC/HDL-C increase CVD mortality in either diabetic or non-diabetic individuals defined based on the fasting glucose criteria, but not the 2-h criteria. TG is a significant CVD risk predictor only in the presence of combined hyperglycaemia or diabetes. The difference between fasting and post-load hyperglycaemia with regard to the lipid-CVD relation may suggest a different pathophysiology underlying these two prediabetic states.