Occupational risk of incident COVID-19 related hospital admissions in two Nordic countries with relaxed and rigorous lockdown

Aims: To compare COVID-19 related hospital admissions among employees in two Nordic countries that applied a relaxed (Skåne, Sweden) and a rigorous (Denmark) lockdown during the pandemic. Methods: We did a register-based follow-up study of the incidence of first-time COVID-19 related hospital admission among all employees aged 20–69 years in Skåne and Denmark. Analyses were performed separately at each site, but according to a uniform study protocol. Adjusted incidence rate ratios (IRRs) during follow-up, 2020 and 2021, for 30 selected occupations were computed by Poisson regression using a reference population of mainly office workers. Results: The incidence of COVID-19 related hospital admission was 2.02/1000 person-years in Skåne (2443 admissions among 607,179 individuals) and 1.01/1000 person-years in Denmark (4416 admissions among 2,451,542 individuals). The relative risk of COVID-19 related hospital admission was increased among healthcare and transportation workers in both countries (Skåne: IRR 1.38 (95% confidence interval (CI) 1.18–1.60) and 1.33 (95% CI 1.08–1.78), respectively; Denmark: IRR 1.56 (95% CI 1.39–1.75) and 1.48 (95% CI 1.23–1.78), respectively). The relative risk for occupations within education, retail sales, and a broad group of service occupations were, with few exceptions, not increased in either country. There was no indication of higher relative risks in Skåne compared with Denmark—if anything the opposite. Conclusions: The relative risk of COVID-19 in at-risk occupations was not higher in a country with relaxed lockdown compared with a country applying rigorous legal lockdown. However, higher absolute risk of infection in Skåne, Sweden might have attenuated occupational differences in hospital admissions.