Temporal trends in medication use and outcomes in atrial fibrillation

Background — Novel therapies for anticoagulation and rhythm control for atrial fibrillation (AF) have been developed recently. To best evaluate the comparative effectiveness of newer agents, practice patterns and outcomes of existing therapies must be characterized at the population level.

Methods — The researchers conducted a retrospective population-based cohort study of patients ≥65 years with a first diagnosis of AF over a 9-year period in Quebec and Ontario. Using hospital and drug claims databases, trends of filled prescriptions, and rates of strokes, bleeding complications, and mortality within 1 year were estimated.

Results — From 1998 to 2006, 338,479 patients were hospitalized with an AF diagnosis. Median age was 77.5 years and 50.4% were male. Use of rate control was 3-fold higher than rhythm control therapy. There was a modest decrease in rate control therapy until 2001 (71.9% to 70.6%, P=0.01), followed by a progressive increase (70.6% to 76.4%, P=0.014). An opposite trend was observed for rhythm control. Although warfarin prescriptions increased (51.0% to 64.5%,P<0.0001), stroke rates tended to decrease (3.8% to 3.5%, P=0.148). Bleeding complications increased mostly because of emergency room visits (4.8% to 6.1%, P=0.007). Mortality remained high despite a small but statistically significant decline (27.6% to 25.8%, P=0.018).

Conclusions — With increased anticoagulation use, stroke rates are declining and emergency room bleeding complications are increasing. Despite an increased use of evidence-based AF therapies, mortality remains high in this population. These findings highlight the need to focus on AF prevention in addition to minimizing its complications.