Changes in shift patterns due to the COVID-19 pandemic: a prospective cohort study of the intensive care nursing staff in hospitals in Stockholm.

Background: It is well known that the COVID-19 pandemic placed pressure on healthcare, leading to increased job demands for intensive care unit (ICU) nursing staff and possibly also longer working hours. Potential changes in shift patterns for ICU nursing staff are important to study as numerous studies collectively indicate that certain shift patterns, especially night shifts, increase the risk of developing various diseases, such as diabetes, cardiovascular diseases, and preterm birth among nursing staff. Objective: To inform crisis planning, the aim was to investigate potential changes in shift patterns among ICU nursing staff working in public hospitals in Stockholm during the pandemic (March 1, 2020-May 31, 2022). Specifically, we investigated changes in the number of day, evening, night, and long shifts; quick returns from evening and night shifts; and mean monthly work hours corresponding to each peak of COVID-19. Design: A prospective cohort study. Setting: ICU in four public hospitals in Stockholm. Participants: Nursing staff, i.e., nurses, specialist nurses, and assistant nurses working in the ICU ( Method: Data were obtained from a computerised administrative employee register in Region Stockholm, which includes detailed information on hours worked. Interrupted time series regressions, modelled with three interruptions, one for each peak of COVID-19 patient influx, were used to investigate whether COVID-19 had an impact on shift patterns. Results: Results showed that the first peak of COVID-19 led to an immediate increase in the number of night shifts by 673.15 shifts (95 % confidence interval (CI): 487.25-859.04), quick returns from night shifts by 443.44 (CI 265.03-621.85) and ≥3 consecutive night shifts by 201.51 (CI 116.57-286.46). Following the first peak, both the number of night shifts and quick returns from night shifts declined. At peak two, the number of night shifts and quick return from night shifts increased by 450.01 (CI 285.85-614.18) and 397.45 (CI 220.43-574.46), respectively. At the third peak, there was an immediate decrease in the number of working days in a row. However, from the second month, a statistically significant upward trend was observed in both the number of night shifts and quick return from night shifts. Conclusions: During the COVID-19 pandemic, (ICU nursing staff experienced an increase in both the number of night shifts and quick returns from night shifts. These types of shifts may lead to adverse health effects and should be minimised. Healthcare organisations should prepare for shift schedules during times of strain to prevent an increase in hazardous shifts. Study registration: Not registered.