Associations between initial American Board of Internal Medicine certification and maintenance of certification status of attending physicians and in-hospital mortality of patients with acute myocardial infarction or congestive heart failure: a retrospective cohort study of hospitalisations in Pennsylvania, USA

OBJECTIVE: To determine whether internists' initial specialty certification and the maintenance of that certification (MOC) is associated with lower in-hospital mortality for their patients with acute myocardial infarction (AMI) or congestive heart failure (CHF). DESIGN: Retrospective cohort study of hospitalisations in Pennsylvania, USA, from 2012 to 2017. SETTING: All hospitals in Pennsylvania. PARTICIPANTS: All 184 115 hospitalisations for primary diagnoses of AMI or CHF where the attending physician was a self-designated internist. PRIMARY OUTCOME MEASURE: In-hospital mortality. RESULTS: Of the 2575 physicians, 2238 had initial certification and 820 were eligible for MOC. After controlling for patient demographics and clinical characteristics, hospital-level factors and physicians' demographic and medical school characteristics, both initial certification and MOC were associated with lower mortality. The adjusted OR for initial certification was 0.835 (95% CI 0.756 to 0.922; p<0.001). Patients cared for by physicians with initial certification had a 15.87% decrease in mortality compared with those cared for by non-certified physicians (mortality rate difference of 5.09 per 1000 patients; 95% CI 2.12 to 8.05; p<0.001). The adjusted OR for MOC was 0.804 (95% CI 0.697 to 0.926; p=0.003). Patients cared for by physicians who completed MOC had an 18.91% decrease in mortality compared with those cared for by MOC lapsed physicians (mortality rate difference of 6.22 per 1000 patients; 95% CI 2.0 to 10.4; p=0.004). CONCLUSIONS: Initial certification was associated with lower mortality for AMI or CHF. Moreover, for patients whose physicians had initial certification, an additional advantage was associated with its maintenance.