High HDL-C concentrations up CVD risk regardless of diabetes status

High concentrations of high-density lipoprotein cholesterol (HDL-C) potentially lead to an increased risk of composite cardiovascular disease (CVD) outcomes in individuals with or without diabetes mellitus (DM), reveals a recent study. Low HDL-C concentrations, however, do not predict future CVD risk in individuals with DM.

Overall, 91,354 Chinese adults (8,244 with DM and 83,110 without DM) free of CVD or cancer at baseline (2006) and without use of lipid-lowering drugs at baseline and during follow-up were included in the analysis. A composite of CVDs (eg, myocardial infarction, ischaemic stroke, haemorrhagic stroke) was the primary endpoint.

The investigators calculated the cumulative average HDL-C concentrations from all available HDL-C measures at baseline (2006) and during follow-up (2008, 2010, 2012, and 2014).

A total of 5,076 CVD events occurred during a mean follow-up of 10.4 years. A significant interaction was observed between DM and HDL-C concentrations on CVD risk (p_interaction=0.003). In participants without DM, the association between HDL-C concentrations and CVD followed a U-shaped curve (p_interaction<0.001).

Compared to the lowest-risk group (HDL-C concentrations of 1.30–1.42 mmol/L), the adjusted hazard ratio (HR) of CVD was 1.26 (95 percent confidence interval [CI], 1.07–1.48) for HDL-C concentrations <1.04 mmol/L and 1.76 (95 percent CI, 1.53–2.03) for HDL-C concentrations >2.07 mmol/L.

In participants with DM, higher HDL-C concentrations contributed to a higher risk of CVD in a dose-dependent manner (p_nonlinearity=0.44; p_trend<0.001). Furthermore, the adjusted HR of CVD for HDL-C concentrations >2.07 mmol/L was 1.62 (95 percent CI, 1.19–2.20) compared with HDL-C concentrations of 1.30–1.42 mmol/L.