Abstract 9371: Low In-Treatment HDL Cholesterol Strongly Predicts Incident Atrial Fibrillation: The LIFE Study

Abstract

Background: Hypertensive patients are at increased risk of atrial fibrillation (AF). Although low baseline HDL levels have been associated with a higher risk of AF in some analyses, this has not been born out in recent population-based studies; whether changing levels of HDL over time are more strongly related to the risk of new AF has not been examined. Methods: Incident AF was examined in relation to baseline and in-treatment HDL levels prior to development of AF in 8267 hypertensive patients with no history of AF, in sinus rhythm on their baseline ECG, randomly assigned to losartan- or atenolol-based treatment. HDL levels at baseline and each year of testing were categorized into quartiles according to baseline HDL levels. Results: During 4.7±1.1 years follow-up, new AF developed in 645 patients (7.8%). In univariate analyses, compared with HDL >1.78 mMol/L, patients with in-treatment HDL <1.21 entered as a time-varying covariate had a 53% greater risk of new AF; patients with in-treatment HDL in the 2 nd or 3 rd quartiles had intermediate increased risks of AF. Baseline HDL was only a weak predictor of new AF. In multivariate Cox analyses adjusting for multiple AF risk factors, including the previously demonstrated predictive value of in-treatment heart rate and Cornell product LVH, there was no attenuation of the risk of new AF associated with low in-treatment HDL. In-treatment non-HDL cholesterol (p=0.171) and statin use (p=0.626) were not significant predictors of new AF in the multivariate model including in-treatment HDL. Baseline HDL was not a significant predictor of AF in multivariate analysis. Conclusions: Lower in-treatment HDL is strongly associated with risk of new AF, even after adjusting for other potential AF risk factors and treatment effects. These findings suggest that serial assessment of HDL can better estimate AF risk in hypertensive patients. Further study is indicated to determine whether therapies that increase HDL can lower risk of developing AF.