The Association between a Lifestyle Score, Socioeconomic Status, and COVID-19 Outcomes within the UK Biobank Cohort

Background: COVID-19 impacts disadvantaged groups most. Lifestyle factors are associated with adverse COVID-19 outcomes. We explored effect modification of socioeconomic-status (SES) on associations between lifestyle and COVID-19. Methods: Using UK-Biobank, we assigned participants a lifestyle-score (LS) comprising nine factors. Poisson regression models with penalised splines were used to analyse associations between LS, deprivation (Townsend) and COVID-19 mortality and severe COVID-19. Associations between each exposure and outcome were examined independently before participants were dichotomised by deprivation to examine exposures jointly. Models were adjusted for sociodemographic/health factors. Findings: Of 343,845 participants, 707 (0·21%) died from COVID-19 and 2,467 (0·75%) had severe COVID-19. There was evidence of a nonlinear association between LS and COVID-19 mortality but limited evidence for nonlinearity between LS and severe COVID-19 and between deprivation and COVID-19 outcomes. Compared with low deprivation, participants in the high deprivation group had higher risk of COVID-19 outcomes across the LS. There was evidence for an additive LS-deprivation interaction. Compared with participants with the healthiest LS in the low deprivation group, COVID-19 mortality risk ratios (95% CIs) for those with less healthy scores in low versus high deprivation groups were 5·09 (1·39-25·20) and 9·60 (4·70-21·44), respectively. Equivalent figures for severe COVID-19 were 5·17 (2·46-12·01) and 6·02 (4·72-7·71). Alternative SES measures produced similar results. Interpretation: Unhealthy lifestyles are associated with higher risk of adverse COVID-19, but risks are highest in the most disadvantaged, suggesting an additive influence between SES and lifestyle. COVID-19 policy and interventions should consider both lifestyle and SES. Funding: Medical Research Council Declaration of Interest: None to declare. Ethical Approval: This study is part of UK Biobank project 7155. UK Biobank studies have ethical approval from the NHS Health Research Authority (21/NW/0157).