Effect of cardiovascular drug classes on all-cause mortality among atrial fibrillation patients treated in primary care in Sweden: a cohort study

Abstract

Risk factors for stroke are well known in atrial fibrillation (AF) patients, while less is known on the effect of these factors on total mortality. Our aim was to study the impact of cardiovascular drug classes on mortality in AF patients treated in primary care. The study population was chosen based on patient data from 75 primary care centres in Sweden compiled in a database. Individuals diagnosed with AF who were older than 45 years were enrolled (n = 12,302, of whom 6,660 were men). Cox regression analysis with mortality (years to death) as outcome was conducted in the men and women separately, as well in the age categories <80 and ≥ 80 years, with cardiovascular drugs as independent factors, and age, cardiovascular diagnoses and educational level as covariates. Lower mortality was shown for anticoagulant treatment among men, both younger (<80 years) [adjusted hazard ratio (HR) 0.43, 95 % confidence interval (CI) 0.31-0.61] and older (≥ 80 years) (adjusted HR 0.47, 95 % CI 0.32-0.69), and among younger women (adjusted HR 0.46, 95 % CI 0.29-0.74), and for antiplatelet treatment in older men (adjusted HR 0.51, 95 % CI 0.35-0.74). Treatment with thiazides was associated with lower mortality among younger men (adjusted HR 0.68, 95 % CI 0.48-0.96), older men (adjusted HR 0.67, 95 % CI 0.46-0.98) and older women (adjusted HR 0.70, 95 % CI 0.52-0.94). Statins were associated with lower mortality among younger patients, in both men (adjusted HR 0.47, 95 % CI 0.32-0.68) and women (adjusted HR 0.54, 95 % CI 0.35-0.82). The differences in age and gender patterns need further exploration.