At this time, news editorials were noting obesity as an underappreciated risk factor for COVID-19.4 This risk is particularly relevant in the USA because the prevalence of obesity is around 40%, versus a prevalence of 6·2% in China, 20% in Italy, and 24% in Spain.5 With use of least squares univariate and multivariate linear regression, we examined the correlation between body-mass index (BMI) and age in patients with COVID-19 admitted to ICU at university hospitals at Johns Hopkins, University of Cincinnati, New York University, University of Washington, Florida Health, and University of Pennsylvania (appendix). Obesity can restrict ventilation by impeding diaphragm excursion, impairs immune responses to viral infection,6 is pro-inflammatory, and induces diabetes and oxidant stress to adversely affect cardiovascular function.7 We conclude that in populations with a high prevalence of obesity, COVID-19 will affect younger populations more than previously reported. Public messaging to younger adults, reducing the threshold for virus testing in obese individuals, and maintaining greater vigilance for this at-risk population should reduce the prevalence of severe COVID-19 disease.