Association of Obesity With In-Hospital Mortality of Cardiogenic Shock Complicating Acute Myocardial Infarction

Several previous studies have shown obesity to be counterintuitively associated with more favorable mortality in patients with acute myocardial infarction (AMI); however, the association of obesity with in-hospital mortality of cardiogenic shock complicating AMI has not been previously examined. We queried the 2004 to 2013 National Inpatient Sample databases to identify all patients ≥18 years hospitalized with the principal diagnosis of AMI. Multivariable regression models adjusting for demographics, hospital characteristics, and co-morbidities were used to examine differences in incidence and in-hospital mortality of cardiogenic shock complicating AMI between obese and nonobese patients. Of 6,097,817 patients with AMI, 290,894 (4.8%) had cardiogenic shock. There was no difference in risk-adjusted incidence of cardiogenic shock between obese and nonobese patients (adjusted odds ratio 1.00, 95% CI 0.98 to 1.01; p = 0.46). Of the patients with cardiogenic shock complicating AMI, 8.9% had a documented diagnosis of obesity. Obese patients were on average 6 years younger and had higher prevalence of most cardiovascular co-morbidities. Obese patients were more likely to receive revascularization (73.0% vs 63.4%, p <0.001) and had lower risk-adjusted in-hospital mortality compared with nonobese patients (28.2% vs 36.5%; adjusted odds ratio 0.89, 95% CI 0.86 to 0.92; p <0.001). Similar findings were seen in subgroups of patients with cardiogenic shock complicating ST elevation or non-ST elevation MI. In conclusion, this large retrospective analysis of a nationwide cohort of patients with cardiogenic shock complicating AMI demonstrated that obese patients were younger, more likely to receive revascularization, and had modestly lower risk-adjusted in-hospital mortality compared with nonobese patients.