Obesity, ethnicity, and other characteristics have emerged as risk factors for adverse COVID-19 associated outcomes, yet studies have not satisfactorily disengaged their effects. This retrospective cohort study was aimed to determine the effect of body mass index, associated comorbidities, time, sociodemographics, and other risk factors for death due to COVID-19. This study’s setting was in Kaiser Permanente Southern California, a large integrated health care organization with members diagnosed with COVID-19 from 13 February to 2 May 2020. Multivariable Poisson regression was used to estimate BMI’s adjusted effect and other factors on risk for death at 21 days; models were also stratified by age and sex.
Among 7000 COVID-19 patients, there was a J-shaped association between body mass index and death risk, even after adjusting for obesity-related comorbidities. This risk was incredibly high amongst men aged sixty years or less. Increased risk for death associated with black ethnicity or other sociodemographic characteristics was not observed. In summary, we found that obesity was strongly associated with risk for death among our study population of infected patients. Younger male patients with high BMI are suspected to be at exceptionally high risk. However, the findings also stress the need for future collaborative efforts to combat the equally devastating force of the obesity epidemic.