Rivaroxaban safety and adherence in patients with nonvalvular atrial fibrillation: prospective, observational, cohort, postmarketing study

The aim of this study was to evaluate real-world rivaroxaban safety and adherence in patients with nonvalvular atrial fibrillation (NVAF). A prospective, observational, cohort, postmarketing study was conducted during a six-month period. The primary outcome was bleeding, including major bleeding, non-major bleeding, and fecal occult blood test positivity. Secondary outcomes included non-bleeding adverse reactions, changes in laboratory parameters, and therapy adherence measured by the Morisky Medication Adherence Scale-8 (MMAS-8). We included 1184 patients evaluated at baseline and at one, three, and six months. During follow-up, cumulative incidences (95% confidence interval) were 0.9% (0.5-1.7%) for major bleeding, 13.3% (11.4-15.3%) for non-major bleeding, and 3.4% (2.4-4.6%) for fecal occult blood positivity. Other adverse drug reactions were infrequent and mild, most commonly headache and fatigue, and no clinically relevant deterioration of laboratory parameters was observed. MMAS-8 score was the same throughout the follow-up period and was 1.0 (interquartile range 0.0-2.0), which is in the domain of good therapy adherence. Approximately one-third of patients demonstrated full therapy adherence, and one-fifth of patients exhibited poor adherence. This real-world study supports the favorable safety profile and generally good patient adherence to rivaroxaban in NVAF, though continued monitoring of bleeding risk and enhanced patient education on adherence remain crucial for optimal outcomes.