Blood lipid profiles and risk of atrial fibrillation: A systematic review and meta-analysis of cohort studies

Background There is an increasing body of evidence associating traditional cardiovascular risk factors with atrial fibrillation (AF), but the relationship between blood lipid profiles and the risk of AF remains controversial. Objective To conduct a systemic review and meta-analysis of large cohort studies to evaluate the relationship between blood lipid profiles and incident AF. Methods PubMed and Embase were searched up to 31st January 2019 for cohort studies that reported the relationship between blood lipid levels and incident AF. The hazard ratios or odd ratios of the highest vs lowest categories of lipid levels were extracted to calculate pooled estimates. Sensitivity analysis and meta-regression were performed to explore potential sources of heterogeneity. Results Eleven studies were included in the meta-analysis, including nine studies for total cholesterol (TC), five for low-density lipoprotein cholesterol (LDL-c), eight for high-density lipoprotein cholesterol (HDL-c), and eight for triglyceride. Serum TC and LDL-c levels were inversely related to AF risk (RR = 0.81, 95% confidence interval [CI]: 0.72-0.92; RR = 0.79, 95% CI: 0.70-0.88, respectively). Likewise, elevated HDL-c levels were associated with a reduced AF risk (RR = 0.86, 95% CI: 0.76-0.97), while no significant association was observed between triglyceride levels and incident AF (RR = 1.02, 95% CI:0.90-1.17). Conclusions Our meta-analysis of large cohort studies found an inverse relationship between serum TC, LDL-c, and HDL-c levels and AF risk, while there was no significant association between TG levels and incident AF. Future studies regarding AF risk stratification may take these blood lipids into consideration and further efforts are needed to investigate the potential mechanisms.