Age-related trends in lipid levels: a large-scale cross-sectional study of the general Chinese population

Objectives This study aimed to investigate the dynamic trends in total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels with ageing. Design A Chinese population-based cross-sectional study. Setting A physical examination centre of a general hospital. Participants Adult subjects (178 167: 103 461 men and 74 706 women) without a known medical history or treatments that affect lipid metabolism. Main outcome measures Dynamic trends in the above-mentioned lipid parameters with ageing were explored; turning points of age were established using age stratification and validated by fitted multivariate linear regression modelling. Results Age was found to be an independent factor extensively associated with lipid levels in both sexes when adjusted for serum glucose, body mass index, lifestyle, drinking and smoking. Age was positively associated with TC, logarithm-transformed TG (LnTG) and LDL-C levels in men <= 40, <= 40 and <= 60 years old (yo) and in women <= 60, <= 70 and <= 60 yo, respectively. Conversely, age correlated negatively with TC, LnTG and LDL-C levels in men >= 61, >= 41 and >= 61 yo and in women >= 61, >= 71 and >= 61 yo, respectively. TC, TG and LDL-C levels in women were initially lower than those in men but surpassed those in men in 51-55, 61-65 and 51-55 yo age groups. The trends in HDL-C levels with age were relatively irregular, although HDL-C levels in women were higher than in men for all age groups. Conclusions The definition of dyslipidaemia, the atherosclerotic cardiovascular disease risk assessment and the initiation/goals of statin therapy should fully consider age-related trends in lipid levels and sex differences.