Lipid levels, apolipoproteins, and risk of incident atrial fibrillation in men: A report from the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD).

BACKGROUND: Apolipoproteins are associated with risk of coronary heart disease but the association with risk of incident atrial fibrillation (AF) has been inconsistent. OBJECTIVES: This study investigated the association of apolipoproteins A-1 (apoA-1) and B (apoB), and lipid levels including triglyceride (TG), total cholesterol (TC), very low-density lipoprotein cholesterol (VLDL-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), with the risk of new-onset AF. METHODS: A total of 2533 men from the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study, aged 42-60 years, were studied. Cox proportional hazards adjusted for potential confounders was used to estimate hazard ratio (HR) of incident events across serum lipid, lipoprotein, and apoA-1 and apoB concentrations. RESULTS: During the mean follow-up of 22.4 years, 594 AF cases occurred. Cox proportional hazards regression indicated that higher serum HDL-C and apoA-1 concentrations were associated with lower risk of AF [the extreme-quartile multivariable-adjusted HR 0.72 (95% CI 0.57-0.92, P = 0.02) for HDL-C, and 0.72 (95% CI 0.52-1.00, P = 0.05)] for apoA-1]. No significant associations were observed for apoB and other lipids (TC, VLDL-C, LDL-C, non-HDL-C, and TG) with risk of incident AF. CONCLUSION: Over the time of follow-up in this study lower new-onset incident AF was in association with higher HDL-C and apo-A1 levels. Future studies should investigate mechanisms underlying the association of low HDL-C and low apoA1 with higher risk of incident AF.