Objective: This study assesses whether chronotype is related to COVID-19 infection and whether there is an interaction with shift work.
Methods: Cross-sectional survey of 19,821 U.S. adults.
Results: COVID-19 infection occurred in 40% of participants, 32.6% morning and 17.2% evening chronotypes. After adjusting for demographic and socioeconomic factors, shift work, sleep duration and comorbidities, morning chronotype was associated with a higher (aOR: 1.15, 95% CI 1.10-1.21) and evening chronotype with a lower (aOR: 0.82, 95% CI: 0.78-0.87) prevalence of COVID-19 infection in comparison to an intermediate chronotype. Working exclusively night shifts was not associated with higher prevalence of COVID-19. Morning chronotype and working some evening shifts was associated with the highest prevalence of previous COVID-19 infection (aOR: 1.87, 95% CI: 1.28-2.74).
Conclusion: Morning chronotype and working a mixture of shifts increase risk of COVID-19 infection.
Keywords: COVID-19; Shift work; chronotype; diurnal preference.