S2 Vigorous exercise is protective against COVID-19: cross-sectional analysis of baseline data from 9,817 UK adults participating in the COVIDENCE UK study

Introduction and Objectives Identification of modifiable risk factors for COVID-19 can inform development of public health policies to improve disease control. The COVIDENCE UK study is a population-based 5-year longitudinal study investigating risk factors for, and impacts of, COVID-19 in the UK population. Methods UK residents aged ≥16 years were invited via a national media campaign to participate in the COVIDENCE UK study by completion of an on-line questionnaire capturing information about potential risk factors for COVID-19. Details of potential symptoms of COVID-19 occurring since 1st February 2020 were also captured, and used to identify those who had experienced probable COVID-19 using an algorithm validated against PCR-positivity for SARS-CoV-2 infection. Multivariable logistic regression was then applied to identify factors independently associated with risk of probable COVID-19, with adjustment for fifteen potential confounders including age, sex and ethnic origin. Results A total of 9,817 participants completed the COVIDENCE UK baseline questionnaire between 1st May and 12th August 2020, of whom 982 (10.0%) were classified as having had probable COVID-19. Increased risk of probable COVID-19 was independently associated with lower household income (adjusted odds ratio [aOR] 1.52, 95% confidence interval [CI] 1.23 to 1.87), being overweight (BMI 25–30 kg/m2, aOR 1.19, 95% CI 1.01 to 1.39), poorer self-reported general health (aOR 1.33, 95% CI 1.09 to 1.61) and employment as a ‘frontline worker’ (aOR 1.57, 95% CI 1.34 to 1.84). Taking at least one hour of vigorous physical exercise per week was associated with a lower risk (aOR 0.77, 95% CI 0.67 to 0.89). Conclusions Lack of vigorous exercise may be a potentially modifiable risk factor for COVID-19. Lower household income, higher BMI, poorer self-reported general health and employment as a frontline worker were also independently associated with increased risk of disease.