Effects of seasonality and daylight savings time on emergency department visits for mental health disorders

Objectives: Emergency Department (ED) utilization accounts for a large portion of healthcare services in the US. Disturbance of circadian rhythms may affect mental and behavioral health (MBH) conditions, which could result in increased ED visits and subsequent hospitalizations, thus potentially inducing staffing shortages and increasing ED wait time. Predicting the burden of ED admissions helps to better plan care at the EDs and provides significant benefits. This study investigates if increased ED visits for MBH conditions are associated with seasonality and changes in daylight savings time. Methods: Using ED encounter data from a large academic medical center, we have examined univariate and multivariate associations between ED visits for MBH conditions and the annual time periods during which MBH conditions are more elevated due to changes in the seasons. We hypothesize that ED visits for MBH conditions increase within the 2-week period following the daylight savings time changes. Results: Increased MBH ED visits were observed in certain seasons. This was especially true for non-bipolar depressive illness. We saw no significant changes in MBH visits as associated with changes in the daylight savings time. Conclusions: Data do not provide conclusive evidence of a uniform seasonal increase in ED visits for MBH conditions. Variation in ED MBH visits may be due to secular trends, such as socioeconomic factors. Future research should explore contemporaneous associations between time-driven events and MBH ED visits. It will allow for greater understanding of challenges regarding psychiatric patients and opportunities for improvement.