The Relationship Between the Body Mass Index and In-Hospital Mortality in Patients Admitted for Sudden Cardiac Death

Background: While obesity has been shown to be associated with increased incidence and severity of major cardiovascular risk factors and elevated risk for Sudden Cardiac Death (SCD), studies examining its effect on outcomes in SCD victims have shown conflicting results. We aimed at describing the BMI distribution in a nationwide cohort of patients, admitted for an out of hospital SCD (OHSCD), and the relationship between BMI and in-hospital mortality.

Methods: We drew data from the U.S. National Inpatient Sample (NIS), to identify cases of OHSCD, between October 2015 and December 2016. The patients were divided into 6 groups based on their BMI (underweight, normal weight, overweight, obese I, obese II, extremely obese). Socio-demographic and clinical data were collected, and incidence of mortality and length of stay were analyzed. Multivariate analysis was performed to identify independent predictors of mortality.

Results: Among a weighted total of 2330 hospitalizations for OHSCD in patients with documented BMI, the mean age was 62.3+29 years, majority of patients (52.4%) were male and 62% were white. The overall rate of in-hospital mortality during the study period was 69.3%. A U-shaped relationship between the BMI and in-hospital mortality was documented, as patients with 25

Conclusion: A U-shaped relationship between the BMI and in-hospital mortality was documented in patients hospitalized for an out of hospital sudden cardiac death in the U.S. in the recent years. These findings support the existence of an “obesity paradox” in patients hospitalized following an OHSCD event.