The impact of obesity on COVID-19 complications: a retrospective cohort study

BACKGROUND: Obesity is an epidemic in New York City, the global epicenter of the coronavirus pandemic. Previous studies suggest that obesity is a possible risk factor for adverse outcomes in COVID-19. OBJECTIVE: To elucidate the association between obesity and COVID-19 outcomes. DESIGN: Retrospective cohort study of COVID-19 hospitalized patients tested between March 10 and April 13, 2020. SETTING: SUNY Downstate Health Sciences University, a COVID-only hospital in New York. PARTICIPANTS: In total, 684 patients were tested for COVID-19 and 504 were analyzed. Patients were categorized into three groups by BMI: normal (BMI 18.50–24.99), overweight (BMI 25.00–29.99), and obese (BMI ≥ 30.00). MEASUREMENTS: Primary outcome was 30-day in-hospital mortality, and secondary outcomes were intubation, acute kidney injury (AKI), acute respiratory distress syndrome (ARDS), and acute cardiac injury (ACI). RESULTS: There were 139 patients (27%) with normal BMI, 150 patients who were overweight (30%), and 215 patients with obesity (43%). After controlling for age, gender, diabetes, hypertension, and qSOFA score, there was a significantly increased risk of mortality in the overweight (RR 1.4, 95% CI 1.1–1.9) and obese groups (RR 1.3, 95% CI 1.0–1.7) compared with those with normal BMI. Similarly, there was a significantly increased relative risk for intubation in the overweight (RR 2.0, 95% CI 1.2–3.3) and obese groups (RR 2.4, 95% CI 1.5–4.0) compared with those with normal BMI. Obesity did not affect rates of AKI, ACI, or ARDS. Furthermore, obesity appears to significantly increase the risk of mortality in males (RR 1.4, 95% CI 1.0-2.0, P = 0.03), but not in females (RR 1.2, 95% CI 0.77–1.9, P = 0.40). CONCLUSION: This study reveals that patients with overweight and obesity who have COVID-19 are at increased risk for mortality and intubation compared to those with normal BMI. These findings support the hypothesis that obesity is a risk factor for COVID-19 complications and should be a consideration in management of COVID-19.