National trends in recurrent AMI hospitalizations 1 year after acute myocardial infarction in medicare beneficiaries: 1999-2010

Background-there are few data characterizing temporal changes in hospitalization for recurrent acute myocardial infarction (ami) after ami. methods and results-using a national sample of 2 305 441 medicare beneficiaries hospitalized for ami from 1999 to 2010,we evaluated changes in the incidence of 1-year recurrent ami hospitalization and mortality using cox proportional hazards models. the observed recurrent ami hospitalization rate declined from 12.1% (95% ci 11.9 to 12.2) in 1999 to 8.9% (95% ci 8.8 to 9.1) in 2010,a relative decline of 26.4%. the observed recurrent ami hospitalization rate declined by a relative 27.7% in whites,from 11.9% (95% ci 11.8 to 12.1) to 8.6% (95% ci 8.5 to 8.8) versus a relative decline in blacks of 13.6% from 13.2% (95% ci 12.6 to 13.8) to 11.4% (95% ci 10.9 to 12.0). the risk-adjusted rate of annual decline in recurrent ami hospitalizations was 4.1% (hr 0.959; 95% ci 0.958 to 0.961),and whites experienced a higher rate of decline (hr 0.957,95% ci 0.956 to 0.959) than blacks (hr 0.974,95% ci 0.970 to 0.979).the overall,observed 1-year mortality rate after hospitalization for recurrent ami declined from 32.4% in 1999 to 29.7% in 2010,a relative decline of 8.3% (p<0.05). in adjusted analyses,1-year mortality after recurrent ami hospitalization declined 1.8% per year (hr,0.982; 95% ci 0.980 to 0.985). conclusions-in a national sample of medicare beneficiaries hospitalized for ami from 1999 to 2010,hospitalization for recurrent ami decreased,as did subsequent mortality,albeit to a lesser extent. the risk of recurrent ami hospitalization declined less in black patients than in whites,increasing observed racial disparities by the end of the study period. © 2014 the authors. published on behalf of the american heart association,inc.,by wiley blackwell.