Living alone and risk of cardiovascular events following discharge after acute myocardial infarction in Japan

Background: Little is known about the long-term risk of cardiovascular events after discharge among acute myocardial infarction (AMI) survivors living alone in Japan. Methods and results: A large-scale prospective, observational study in the Osaka region involved consecutive patients with AMI from January 2002 through December 2010. We evaluated the association between living alone and longitudinal risk of cardiovascular events following discharge after AMI. A Cox proportional-hazards model was used to assess the association between living alone and the primary composite endpoint consisting of major adverse cardiovascular events and total deaths. During the study period, 5845 patients (4415 male patients, 1430 female patients) were registered. Living alone was found to be independently associated with a higher risk of composite endpoint consisting of major adverse cardiovascular events and total deaths [adjusted hazard ratio (HR) 1.32; 95% confidence interval (CI): 1.11-1.58]. Multivariate-adjusted HRs of composite endpoint were 1.34 (95% CI: 1.08-1.68) among male patients and 1.31 (95% CI: 0.95-1.81) in the female patients. AMI survivors living alone tend to have a higher adjusted HR of composite endpoint than those not living alone irrespective of age and gender groups. Conclusions: From this large AMI registry in Osaka, AMI survivors living alone after discharge had a higher risk of cardiovascular events and total deaths than those not living alone.