Obesity doubles mortality in patients hospitalized for SARS-CoV-2 in Paris hospitals, France: a cohort study on 5795 patients.

Background Preliminary data from different cohorts of small sample size or with short follow-up indicate poorer prognosis in people with obesity compared to other patients. This study aims to precisely describe the strength of association between obesity in patients hospitalised with Covid-19 and mortality and clarify the risk according to usual cardiometabolic risk factors in a large cohort. Methods This is a prospective cohort study including 5795 patients aged 18-79 years hospitalized from 1st February 2020 to 30 April 2020 in Paris area, with confirmed infection by SARS-CoV-2. Adjusted regression models were used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI) for mortality rate at 30 days across BMI classes, without and with imputation for missing BMI. Results 891 deaths occurred at 30 days. Mortality was significantly raised in people with obesity with the following OR in BMI 30-35, 35-40 and >40 kg/m2 : 1.89 (95%CI 1.45-2.47), 2.79 (1.95-3.97) and 2.55 (1.62-3.95), respectively (18.5-25 kg/m2 , as the reference class). This increase holds for all age classes. Conclusion Obesity doubles mortality in patients hospitalized with Covid-19.