Abstract 4356626: The Obesity Paradox in Heart Failure: Exploring the Impact of BMI on 30-Day Readmission Rates in a Community Safety-Net Hospital

Abstract

Background: Obesity is a well-established risk factor for the development of congestive heart failure (CHF), yet its impact on hospital readmission rates remains unclear. Some studies suggest an “obesity paradox,” where higher body mass index (BMI) may be associated with better short-term outcomes in CHF patients. However, this phenomenon has not been thoroughly explored in underserved populations, where both obesity and CHF are highly prevalent. Research Question: Does BMI category influence 30-day readmission rates in CHF patients at a community safety-net hospital? Methods: We conducted a retrospective chart review of 385 CHF patients (mean age 65±13.8 years; 57.4% male; 74.8% Black/ 2.6% White/ 13.8% Hispanic individuals) admitted to NYC Health + Hospitals/Harlem between February 2019 and December 2020. Patients were categorized by BMI per WHO guidelines. The primary outcome was readmission within 30 days of discharge. Associations between BMI categories and 30-day readmissions were assessed through chi-square tests, Cochran-Armitage trend tests, and nested logistic regression models adjusting for demographic and clinical covariates. Results: Among these patients with CHF, 30.6% (n = 118) had a healthy weight (BMI < 25 kg/m 2 ), 24.7% (n = 95) were overweight, and 44.7% (n = 172) were classified as obese. Each stepwise increase in BMI category was associated with lower likelihood of 30-day readmission (trend test: p = 0.0006). Compared to those with Class III obesity, healthy weight patients had a higher risk of readmission (OR 4.5 [95% CI: 1.5–13.4]; p = 0.001), even after controlling for age, sex, race, and ejection fraction (adjusted OR 4.4 [1.4–14.0]; p = 0.03). When BMI was modeled as a continuous variable, each 5 kg/m 2 increase was associated with a 28% reduction in readmission risk (OR 0.72 [95% CI: 0.59–0.89]; p = 0.0017). Conclusions: This study replicates the “obesity paradox” observed in predominantly White cohorts, demonstrating that higher BMI is similarly associated with lower 30-day readmission rates among CHF patients in a racially and socioeconomically diverse community safety-net hospital. These findings highlight the importance of validating clinical observations across varied demographic groups. Further research is needed to understand the mechanisms underlying this paradox and to inform tailored weight management strategies in CHF care.