Japanese patients with atrial fibrillation have relatively low 1-year mortality and morbidity, though co-morbidities like congestive heart failure and lack of anticoagulation significantly increase mortality risk.
BACKGROUND: Prognosis of Japanese patients with atrial fibrillation (AF) should be determined in a prospective cohort study. METHODS AND RESULTS: A prospective cohort of The Shinken Database 2004 comprised details on all the new patients who visited The Cardiovascular Institute Hospital in 2004 (n=2,412), which included 286 AF patients (11.8%, 205 males, 64.1+/-12.3 years, 165 paroxysmal). In this Japanese cohort of AF patients, the prevalence of congestive heart failure (CHF) was low compared with that in Westerners. Total mortality and cardiovascular morbidity of these patients were also quite low, 1.7% and 11.2% at 1 year, respectively. However, patients with CHF exhibited higher mortality (7.3%), and hospitalization for CHF increased the rate to 22.6%. There was no significant difference in mortality between paroxysmal and persistent AF. Multiple Cox-hazard regression analysis identified hospitalization at initial visit and lack of anticoagulation as independent predictors for mortality, and existence of CHF as the only independent predictor for cardiovascular morbidity. CONCLUSIONS The present study identified the mortality (1.7%) and morbidity (11.2%) of Japanese AF patients during 1 year after initial visit. Hospitalization for CHF and lack of anticoagulation were independent predictors for mortality, suggesting important roles of co-morbidities of Japanese AF patients.
Suzuki et al. (2008) studied this question.