Association of Low-Density Lipoprotein Cholesterol with Risk of Coronary Heart Disease and Stroke among Middle-Aged Japanese Workers: An Analysis using Inverse Probability Weighting

Aims: The associations between low-density lipoprotein cholesterol (LDL-C) and the risk of cardiovascular disease (CVD) subtypes are not well established among the Japanese population. This study used longitudinal data from the Aichi Workers’ Cohort Study to explore the association between LDL-C levels and the risk of coronary heart disease (CHD) and stroke subtypes. Methods: Pooled data of 8966 adults (7093men and 1903 women) who were recruited between (2002) and (2008) were used for the current analysis. Propensity scores for the LDL-C categories were generated using multinomial logistic regression. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from the inverse probability weighted Cox proportional hazards model for LDL-C category associations with risks of CHD, stroke subtypes, and CVD. Results: During a median follow-up of 12 years, 122 strokes (57 ischemic strokes, 25 intracerebral hemorrhage, and 40 unknown subtypes) and 82 cases of CHD were observed. LDL-C 160– mg/dL compared to LDL-C 100– 119 mg/dL was positively and significantly associated with the risk of CHD (HR: 4.56; 95% CI: 1.91–10.9) but not with ischemic stroke (HR: 0.99; 95% CI: 0.44–2.22). LDL-C was inversely associated with the risk of intracerebral hemorrhage (P for trend=0.009). Conclusion: In middle-aged Japanese workers, LDL-C was significantly and positively associated with CHD, but not with ischemic stroke. LDL-C was inversely significantly associated with intracerebral hemorrhage.