Sleep debt doubles infection risk in healthcare workers
A significant association between sleep debt and heightened infection risk has been identified in nurses working irregular shifts, according to research published 10 March 2025 in Chronobiology International, which reveals that healthcare professionals with severe sleep debt face more than double the risk of developing common infections compared to their well-rested counterparts.
Research findings
The comprehensive study, which analysed self-reported data from 1,335 Norwegian nurses, discovered that both sleep debt and night shift patterns negatively impact immune function. Sleep debt – defined as the gap between sleep need and actual sleep duration– demonstrated a dose-dependent relationship with infection susceptibility.
“These findings highlight the need for tailored interventions to reduce infection risks among healthcare workers,” says Siri Waage, senior author of the study and coordinator at the Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen. “Sleep debt and irregular shift patterns, including night work, not only compromise nurses’ immune health but could also impact their ability to provide high-quality patient care.”
Researchers from the Survey of Shift work, Sleep and Health (SUSSH) study found that nurses experiencing severe sleep debt– sleeping more than two hours less than their physiological requirement – faced a 288% increased risk of pneumonia or bronchitis. Even moderate sleep debt (1-120 minutes less sleep than needed) was associated with a 33% higher likelihood of developing the common cold.
Night shift implications
While night work specifically correlated with increased common cold risk, the study did not establish significant associations between night shifts and other infections examined. Interestingly, sleep duration alone and ‘quick returns’ (short intervals between consecutive shifts) showed no significant relationship with infection risk.
The predominantly female cohort (90.4%) had an average age of 41.9 years, with statistical analyses adjusted for variables including age, gender, marital status, and childcare responsibilities.
Professor Ståle Pallesen, co-author and insomnia research specialist at the Department of Psychosocial Science, University of Bergen, suggests potential preventative measures: “Nurses could benefit from optimised shift patterns, such as limiting consecutive night shifts and allowing adequate recovery time between shifts. Raising awareness about the importance of sleep for immune health and encouraging regular health screening and vaccinations for healthcare workers may also be helpful.”
Practical applications
The findings have significant implications for healthcare workforce management and public health policy. While the study’s large sample size strengthens its validity for female nurses over 30, the authors acknowledge limitations regarding its generalisability to men, younger nurses, other professions, or those with different shift work schedules.
Additionally, data collection timing (spring, outside typical flu season) may have resulted in lower reported infection rates than would be expected during winter months.
The research provides compelling evidence for healthcare institutions to consider the immune health consequences of scheduling practices, particularly as they relate to sleep debt accumulation. It contributes to growing scientific literature examining the physiological impacts of circadian rhythm disruption in shift workers.
Reference:
Waage, S., Pallesen, S., et al. (10 March 2025). Night work and sleep debt are associated with infections among Norwegian nurses. Chronobiology International. https://doi.org/10.1080/07420528.2025.2455147
