High total cholesterol in midlife was associated with a lower risk of atrial fibrillation within 5 years (HR 0.61), while low HDL-C and ApoA-I were associated with increased risk over 35 years.
Cohort (n=65,136)
Are midlife blood lipid levels associated with the subsequent risk of new-onset atrial fibrillation in individuals without overt cardiovascular disease?
Metabolic syndrome and inflammation markers (low HDL-C, high TG/HDL-C ratio), rather than high LDL-C, are associated with long-term incident atrial fibrillation risk.
Hazard Ratio: 0.61 (95% CI 0.41–0.99)
p-value: p=0.013
BACKGROUND: The role of cholesterol levels in the development of atrial fibrillation (AF) is still controversial. In addition, whether and to what extent apolipoproteins are associated with the risk of AF is rarely studied. In this study, we aimed to investigate the association between blood lipid levels in midlife and subsequent risk of new-onset AF. METHODS AND FINDINGS: This population-based study included 65,136 individuals aged 45 to 60 years without overt cardiovascular diseases (CVDs) from the Swedish Apolipoprotein-Related Mortality Risk (AMORIS) cohort. Lipids were measured in 1985 to 1996, and individuals were followed until December 31, 2019 for incident AF (i.e., study outcome). Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox regression, adjusting for age, sex, and socioeconomic status. Over a mean follow-up of 24.2 years (standard deviation 7.5, range 0.2 to 35.9), 13,871 (21.3%) incident AF cases occurred. Higher levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were statistically significantly associated with a lower risk of AF during the first 5 years of follow-up (HR = 0.61, 95% CI: 0.41 to 0.99, p = 0.013; HR = 0.64, 95% CI: 0.45 to 0.92, p = 0.016), but not thereafter (HR ranging from 0.94 95% CI: 0.89 to 1.00, p = 0.038 to 0.96 95% CI: 0.77 to 1.19, p > 0.05). Lower levels of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (ApoA-I) and higher triglycerides (TG)/HDL-C ratio were statistically significantly associated with a higher risk of AF during the entire follow-up (HR ranging from 1.13 95% CI: 1.07 to 1.19, p < 0.001 to 1.53 95% CI: 1.12 to 2.00, p = 0.007). Apolipoprotein B (ApoB)/ApoA-I ratio was not associated with AF risk. The observed associations were similar among those who developed incident heart failure (HF)/coronary heart disease (CHD) and those who did not. The main limitations of this study include lack of adjustments for lifestyle factors and high blood pressure leading to potential residual confounding. CONCLUSIONS: High TC and LDL-C in midlife was associated with a lower risk of AF, but this association was present only within 5 years from lipid measurement and not thereafter. On the contrary, low HDL-C and ApoA-I and high TG/HDL-C ratio were associated with an increased risk of AF over almost 35 years of follow-up. ApoB/ApoA-I ratio was not associated with AF risk.
Ding et al. (Thu,) conducted a cohort in Atrial fibrillation (n=65,136). High total cholesterol and LDL-C vs. Reference lipid levels was evaluated on Incident atrial fibrillation (first 5 years of follow-up) (HR 0.61, 95% CI 0.41 to 0.99, p=0.013). High total cholesterol in midlife was associated with a lower risk of atrial fibrillation within 5 years (HR 0.61), while low HDL-C and ApoA-I were associated with increased risk over 35 years.