Background:
Atrial fibrillation (AF) is highly prevalent and poses a significant public health burden on the aging population. We hypothesized that AF independently predicts myocardial infarction (MI) in the Cardiovascular Health Study (CHS).
Methods:
AF was evaluated longitudinally in participants free of cardiovascular disease at baseline in the CHS. Participants were followed for a mean (standard deviation, SD) 12.7 (5.8) years for development of fatal or nonfatal MI. Cox regression models were utilized to assess the associations of time-updated AF and MI in fully adjusted models and models with gender interaction.
Results:
Of the 5888 participants in the CHS, 4158 met the inclusion criteria. The mean (SD) age was 72.3 (5.4) years old (38.3% male, 14.3% African-American). Eighty-two had prevalent AF; 1005 developed incident AF during follow up (AF group, n=1087). To avoid bias, participants diagnosed with AF at the same time as their MI were not included in the AF group. Baseline total cholesterol (212.4 [38.6] mg/dL), systolic blood pressure (SBP, 136.1 [21.4] mmHg), and diabetes mellitus prevalence (13.6%) were similar between groups. AF updated as a time-varying exposure was associated with a higher risk of MI: hazard ratio (HR) 1.61, [95% CI 1.32-1.96], after adjusting for age, gender, race, SBP, total and high-density lipoprotein cholesterol, current smoking, fasting glucose, education, alcohol use, C-reactive protein, body-mass index, diabetes, anti-arrhythmic use, and time-updated use of aspirin, anti-hypertensive and lipid medications. Women were at higher risk (HR 2.00 [95% CI 1.53-2.62]) than men (HR 1.33 [95% CI 0.99-1.77]) (p for interaction=0.02).
Conclusion:
In a large cohort study with over a decade of follow-up, AF was associated with an increased risk for MI. This association was more pronounced in women.
Association of Gene Variants With Incident Myocardial Infarction in the Cardiovascular Health Study