Associations between relevant cardiovascular pharmacotherapies and incident heart failure in patients with atrial fibrillation: a cohort study in primary care

Objective: To study association between relevant cardiovascular pharmacotherapy and incident congestive heart failure (CHF) in patients with atrial fibrillation treated in primary health care. Methods: Study population included all adults (n=7975) aged 45 years and older diagnosed with atrial fibrillation at 75 primary care centers in Sweden between 2001 and 2007. Outcome was defined as a first diagnosis of CHF post-atrial fibrillation diagnosis. Association between CHF and treatment with relevant cardiovascular pharmacotherapies (beta blockers, calcium blockers, digitalis, diuretics, RAS blockers, and statins) was explored using Cox regression analysis with hazard ratios and 95% CIs. Adjustments were made for age, sociodemographic variables, and comorbid conditions (with or without cardiovascular disorders). Results: During a mean of 5.7 years (SD 2.3) of follow-up, totally 1552 patients (19.5%; 803 women and 749 men) had a recorded CHF diagnosis. Thiazides (hazard ratio 0.74, 95% CI 0.65-0.84), vessel-active calcium channel blockers (hazard ratio 0.76, 95% CI 0.67-0.86), and nonselective beta blockers (hazard ratio 0.84, 95% CI 0.72-0.98), with specifically sotalol representing 80% of nonselective beta blockers (hazard ratio 0.81, 95% CI 0.69-0.97), were associated with lower CHF risk in fully adjusted models. Loop diuretics (hazard ratio 1.41, 95% CI 1.25-1.57) were associated with a higher risk. Findings for thiazides and vessel-active channel blockers were consistent in the tested subgroups. Conclusion: In this clinical setting, we found that thiazides, vessel-active calcium channel blockers, and nonselective beta blockers (specifically sotalol) were associated with a lower risk of incident CHF among patients with atrial fibrillation. The findings of the present study need to be confirmed in other settings.