Obesity is an emerging risk factor for coronavirus disease-2019 (COVID-19). Simple measures of physical fitness, such as self-reported walking pace, may also be important risk markers. This analysis includes 412,596 UK Biobank participants with linked
COVID-19 data (median age at linkage = 68 years, obese = 24%, median number of comorbidities = 1). As of August 24th 2020, there were 1001 cases of severe (in-hospital) disease and 336
COVID-19 deaths. Compared to normal weight individuals, the adjusted odds ratio (OR) of severe
COVID-19 in
overweight and obese individuals was 1.26 (1.07, 1.48) and 1.49 (1.25, 1.79), respectively. For
COVID-19 mortality, the
ORs were 1.19 (0.88, 161) and 1.82 (1.33, 2.49), respectively. Compared to those with a brisk walking pace, the OR of severe
COVID-19 for steady/average and slow
walkers was 1.13 (0.98, 1.31) and 1.88 (1.53, 2.31), respectively. For
COVID-19 mortality, the
ORs were 1.44 (1.10, 1.90) and 1.83 (1.26, 2.65), respectively. Slow
walkers had the highest risk regardless of
obesity status. For example, compared to normal weight brisk
walkers, the OR of severe disease and
COVID-19 mortality in normal weight slow
walkers was 2.42 (1.53, 3.84) and 3.75 (1.61, 8.70), respectively. Self-reported slow
walkers appear to be a high-risk group for severe
COVID-19 outcomes independent of
obesity.