Low and high HDL cholesterol levels may increase the risk of serious infectious disease, according to new research.
The study, published in the European Heart Journal, analysed data from the Copenhagen General Population Study (n=97,166) and the Copenhagen City Heart Study (n=9,387). The primary endpoint was any infectious disease requiring hospital admission.
Individuals from the Copenhagen General Population Study were followed for a median of six years (range 0-11 years). A total of 8,282 individuals (9%) experienced one or more infectious disease events during follow-up. Participants from the Copenhagen City Heart Study were followed up for 20 years (0-23 years). Of these, 2,904 (31%) developed an infectious disease event.
HDL cholesterol below 0.8mmol/l was found to be associated with a 75 per cent increased risk for any infection compared to levels of 2.2-2.3mmol/l (adjusted hazard ratio [aHR] 1.75; 95% CI 1.31-2.34). Levels above 2.6mmol/l showed a 43 per cent increased risk (aHR 1.43; 95% CI 1.16-1.76). The highest risk estimates were seen for gastroenteritis and bacterial pneumonia.
The authors say the findings suggest that HDL cholesterol may play a role in the normal function of the immune system.