Night work and sleep debt are associated with infections among Norwegian nurses

This study investigates possible associations between sleep duration, sleep debt and shift work characteristics, and self-reported infections among 1335 Norwegian nurses (90.4% females, mean age 41.9 y). Participants reported their sleep duration, sleep need and shift work, and frequency of infections (common cold, pneumonia/bronchitis, sinusitis, gastrointestinal infection, urinary tract infection) experienced in the last 3 months. Chi-square tests and logistic regression (adjusted for sex, age, children at home, marital status) were used for data analyses. Sleep debt (1-120 min and >2 h, respectively) was dose-dependently associated with increased risk of common cold (adjusted odds ratio (aOR) 1.33, 95% CI 1.00-1.78; aOR 2.32, 95% CI 1.30-4.13), pneumonia/bronchitis (aOR 2.29, 95% CI 1.07-4.90; aOR 3.88, 95% CI 1.44-10.47), sinusitis (aOR 2.08, 95% CI 1.22-3.54; aOR 2.58, 95% CI 1.19-5.59), and gastrointestinal infection (aOR 1.45, 95% CI 1.00-2.11; aOR 2.45, 95% CI 1.39-4.31), compared to no sleep debt. Night work (yes/no) (aOR 1.28, 95% CI 1.00-1.64) and number of night shifts (1-20 compared to 0 nights) (aOR 1.49, 95% CI 1.08-2.06) were associated with increased risk of common cold. Sleep duration and quick returns were not associated with any of the infections. In conclusion, shift- and night work were associated with increased risk of common cold. Sleep debt was dose-dependently associated with an increased risk of several infections.