High-Density Lipoprotein Cholesterol (HDL-C) Levels Independently Correlates With Cardiac Arrhythmias and Atrial Fibrillation

Objective: Acute coronary syndrome is frequently complicated by rhythm disturbances, yet any association between high-density lipoprotein (HDL) cholesterol levels and arrhythmias in the setting of non-ST-segment elevation myocardial infarction (non-STEMI) is uncertain. The goal of this study was to evaluate any association between HDL-cholesterol levels and arrhythmias in the setting of non-STEMI. Methods: Retrospective data from Phoenix Veterans Affair Medical Center records were utilized for our study. A total of 6881 patients were found who presented during 2000 to 2003 with non-STEMI with available fasting lipid panels collected within the first 24 hours of admission. Patients were followed for the development of rhythm disturbances up to 6 years after initial presentation, with a mean follow up of 1269 days. Results: We found that high triglycerides/HDL and low-density lipid/HDL ratios were predictive of arrhythmias. However, low HDL levels had strongest association with highest odds ratio (OR) for development of arrhythmias (for HDL <31 mg/dL, OR = 3.72, 95% confidence interval [CI] = 2.55-5.44, P <.05) in patients with diabetes and (for HDL < 31 mg/dL, OR = 3.69, 95% CI = 2.85-4.71, P <.05) in patients without diabetes. Using multivariate analysis adjusting for comorbidities, low HDL level remained independently associated with arrhythmias. Conclusions: Patients with low HDL levels during hospitalization with non-STEMI have a greater risk of developing cardiac rhythm disturbances independent of other risk factors. These data suggest a possible protective role of HDL in preventing arrhythmias in the setting of acute coronary syndrome.