Weather's influence on the number of emergency psychiatric visits: myth or reality? A systematic review of the literature

Background

The influence of weather on emergency psychiatric visits has been explored in various studies, yet the results have been inconsistent. This systematic review aims to investigate the relationship between meteorological factors and visits to psychiatric emergency departments (ED).

Methods

Following PRISMA guidelines, this review aimed to clarify the relationship between meteorological factors and psychiatric emergency visits. A systematic literature search was conducted using the PubMed, Cochrane Library, and PsycINFO databases up until January 2024. The search focused on identifying studies that examined ED visits for psychiatric reasons and investigated the impact of at least one meteorological factor (including temperature, atmospheric pressure, precipitation, wind, humidity, sunlight exposure, or day length).

Results

Of the 191 articles initially screened, 16 were selected for in-depth analysis. Among these, 10 studies found a significant association between higher temperatures and an increase in psychiatric ED visits. Further subgroup analyses revealed a specific correlation between increased temperature and psychiatric ED visits for mood disorders, psychotic disorders, substance use disorders, suicidal behavior, and anxiety disorders. Research on meteorological factors beyond temperature was notably scarce.

Conclusions

The link between increased temperature and psychiatric emergencies could stem from various biological mechanisms, including the modulation of melatonin and serotonin levels. Gaining insights into how weather conditions affect psychiatric ED visits enables a deeper understanding of the triggers for psychiatric decompensations. This information is crucial for developing targeted preventive strategies and informing public health policies aimed at mitigating the impact of adverse weather on mental health crises.