A Systematic Review of Permanent Night Work vs. Rotating Shift Work with Night Work: Relationships with Mental Health

Introduction: Approximately 20–25% of the global population is engaged in shift work. Shift work has no consensus definition but can be conceptualised as any work schedule that involves work outside traditional daytime hours (i.e., ~8 am to ~6 pm). Therefore, shift work encompasses morning, evening and night work, as well as rotating, permanent and irregular schedules. It is well established that the sleep loss and circadian disruption associated with shift work results in adverse health, psychosocial wellbeing and safety outcomes. As humans are day active, night work poses the greatest challenge to the circadian system. As such, many health and safety regulators and labor organisations worldwide encourage special provisions for health assessments for night workers, and some provide guidance to avoid permanent night work. We conducted a systematic review to evaluate the differential effects of permanent night work (PNW) and rotating shift work that includes night shifts (RWN) on health, safety and performance.