Independent and joint associations of blood lipids and lipoproteins with lung cancer risk in Chinese males: A prospective cohort study

To investigate the independent and joint associations of blood lipids and lipoproteins with lung cancer risk in Chinese males, a prospective cohort study was conducted. A total of 109,798 males with baseline information on total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and non-HDL were prospectively observed from 2006 to 2015 for cancer incidence. Cox proportional hazards models and restricted cubic spline (RCS) analysis were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During a 9-year follow-up, a total of 986 lung cancer cases were identified. Multivariable analyses showed that both males with low TC (HR_Q1vs.Q2 = 1.27, 95%CI: 1.02-1.60) and males with high TC (HR_Q5vs.Q2 = 1.30, 95%CI: 1.04-1.63) had an increased lung cancer risk, and the U-shaped association was also revealed in the RCS analysis (p_overall = 0.013, p_nonlinear = 0.006). Furthermore, both low TG (HR_Q1vs.Q2 = 1.24, 95%CI: 0.99-1.54) and high TG (HR_Q5vs.Q2 = 1.27, 95%CI: 1.01-1.59) were associated with increased lung cancer risk, while low LDL-C (HR_Q1vs.Q2 = 1.38, 95%CI: 1.11-1.72) was associated with increased lung cancer risk. When TC, TG and LDL-C were considered jointly, the number of abnormal indicators was linearly associated with an increased risk of lung cancer (p_trend < 0.001), as subjects with three abnormal indicators had a twofold higher risk of developing lung cancer (HR = 2.02, 95%CI: 1.62-2.54). Notably, these associations were statistically significant among never smokers, never drinkers and overweight/obese males. These findings suggest that dyslipidemia may potentially be a modifiable risk factor that has key scientific and clinical significance for lung cancer prevention.