Role of body mass index in outcomes of patients hospitalized with COVID-19 illness

Obes Sci Pract. 2022 Apr 28;8(6):748-756. doi: 10.1002/osp4.607. eCollection 2022 Dec.

Abstract

Background: Since the start of coronavirus disease 2019 (COVID-19) pandemic, several studies have linked obesity with severity of illness as well as mortality in patients with COVID-19. Outcomes of patients with overweight or obesity, who develop critical illness, have been studied extensively over the past decade where the studies have shown conflicting results. In this study, we aimed to assess the association between the body mass index (BMI) classes and outcomes among hospitalized patients with COVID-19.

Methods: This was a retrospective chart review of all adults admitted to our hospital with COVID-19 illness between 1 March 2020 and 30 June 2020. Patients were divided into four groups based on their BMI range as follows: patients with underweight (BMI < 18.5 kg/m2), patients with normal weight (BMI 18.5-24.9 kg/m2), patients with overweight (BMI 25-29.9 kg/m2), and patients with obesity (BMI ≥ 30 kg/m2).

Results: 1274 patients were admitted during the study period. There were 24 (1.9%) patients with underweight, 268 (21%) patients with normal weight, 445 (34.9%) patients with overweight, and 537 (42.2%) patients with obesity. Patients with obesity were younger (p < 0.001) and there were more females among patients with underweight and patients with obesity (54% and 48% respectively, p < 0.001). There were no differences in subgroup with regards to presence of hypertension, diabetes mellitus, coronary artery disease, congestive heart failure, and dyslipidemia. In a multivariate logistic regression model, patients with overweight and patients with obesity had higher odds of requiring mechanical ventilation. BMI class was not associated with difference in survival time in a multivariate analysis.

Conclusions: In our large single-center study of hospitalized patients with COVID-19, patients with overweight and obesity had higher need for mechanical ventilation but had similar mortality when compared to patients with normal weight and underweight.

Keywords: BMI; COVID‐19.