Association of Body Mass Index and Age With Morbidity and Mortality in Patients Hospitalized With COVID-19

Abstract

Background: Obesity may contribute to adverse outcomes in coronavirus disease 2019 (COVID-19). However, studies of large, broadly generalizable patient populations are lacking, and the effect of body mass index (BMI) on COVID-19 outcomes— particularly in younger adults—remains uncertain. Methods: We analyzed data from patients hospitalized with COVID-19 at 88 US hospitals enrolled in the American Heart Association’s COVID-19 Cardiovascular Disease Registry with data collection through July 22, 2020. BMI was stratified by World Health Organization obesity class, with normal weight prespecified as the reference group. Results: Obesity, and, in particular, class III obesity, was overrepresented in the registry in comparison with the US population, with the largest differences among adults ≤50 years. Among 7606 patients, in-hospital death or mechanical ventilation occurred in 2109 (27.7%), in-hospital death in 1302 (17.1%), and mechanical ventilation in 1602 (21.1%). After multivariable adjustment, classes I to III obesity were associated with higher risks of in-hospital death or mechanical ventilation (odds ratio, 1.28 [95% CI, 1.09–1.51], 1.57 [1.29–1.91], 1.80 [1.47–2.20], respectively), and class III obesity was associated with a higher risk of in-hospital death (hazard ratio, 1.26 [95% CI, 1.00–1.58]). Overweight and class I to III obese individuals were at higher risk for mechanical ventilation (odds ratio, 1.28 [95% CI, 1.09–1.51], 1.54 [1.29–1.84], 1.88 [1.52–2.32], and 2.08 [1.68–2.58], respectively). Significant BMI by age interactions were seen for all primary end points ( P -interaction<0.05 for each), such that the association of BMI with death or mechanical ventilation was strongest in adults ≤50 years, intermediate in adults 51 to 70 years, and weakest in adults >70 years. Severe obesity (BMI ≥40 kg/m 2 ) was associated with an increased risk of in-hospital death only in those ≤50 years (hazard ratio, 1.36 [1.01–1.84]). In adjusted analyses, higher BMI was associated with dialysis initiation and with venous thromboembolism but not with major adverse cardiac events. Conclusions: Obese patients are more likely to be hospitalized with COVID-19, and are at higher risk of in-hospital death or mechanical ventilation, in particular, if young (age ≤50 years). Obese patients are also at higher risk for venous thromboembolism and dialysis. These observations support clear public health messaging and rigorous adherence to COVID-19 prevention strategies in all obese individuals regardless of age.

Body mass index and risk of COVID-19 diagnosis, hospitalisation, and death: a population-based multi-state cohort analysis including 2,524,926 people in Catalonia, Spain

“…[4,5] Other large observational studies from the US and the UK using multiple categories of BMI, only found an association between morbid obesity (BMIs above 35 kg/m 2 or 40 kg/m 2 ) and COVID-19 mortality. [37–40] Our results for high BMIs are consistent with the latter studies, as our analyses revealed BMI was associated in a J-shaped fashion with the risk of COVID-19 related death: only BMIs above 37kg/m 2 and 40kg/m 2 were linked with a higher risk of death after a COVID-19 hospitalisation and after a COVID-19 outpatient diagnosis, respectively. Our findings were also aligned with those of a study conducted in a New York hospital which reported a J-shaped association between BMI and the risk of intubation or death.…”

“…[7] Furthermore, our results provide important insights on the higher risk of COVID-19 related death for low BMIs (≤19kg/m 2 ); while other studies also found this trend in their effect estimates, these were not significant, likely due to their smaller sample sizes. [7,39,40]…”

Nutritional and Behavioral Approaches to Body Composition and Low-Grade Chronic Inflammation Management for Older Adults in the Ordinary and COVID-19 Times

“…Indeed, based on the recent study in almost 2600 hospitalized patients with COVID-19 infection, those with a BMI >40 kg/m 2 who were younger than 65 years were more likely to die or be intubated compared even to their older, but not obese, counterparts [ 17 ]. Similarly, in a study just published in Circulation, an analysis of the data from the American Heart Association COVID-19 Registry from 88 US hospitals showed that patients with obesity were at higher risk of dying in hospital, more frequently required mechanical ventilation, and were at higher risk for thromboembolism and dialysis, regardless of age, compared to non-obese patients [ 18 ].…”

COVID-19 endocrinopathy with hindsight from SARS

“…Related to diabetes mellitus is obesity, in which a recent study revealed that obesity is correlated to higher odds of mechanical ventilation and in-hospital mortality after multivariable adjustment on analyzed data from patients with COVID-19 at 88 hospitals enrolled in the American Heart Association’s COVID-19 Cardiovascular Disease Registry ( 107 ). Notably, among patients ≤ 50 yr of age, BMI ≥ 40 kg/m 2 was linked to a profoundly elevated risk of death or mechanical ventilation (OR, 1.64 [95% CI, 1.23–2.21]), moderately increased odds in those aged 51–70 (OR, 1.40 [1.10–1.80]), but no significant increase in risk among patients > 70 yr old (OR, 1.28 [0.83–1.95]).…”