Barometric Pressure, Emergency Psychiatric Visits, and Violent Acts

Abstract

Background: Associations between human behaviour and psychiatric decompensation and weather variables have been inconsistent. Objectives: We studied the association of certain weather variables (specifically, humidity, wind speed, and barometric pressure) with emergent psychiatric presentations, psychiatric admissions, incidence of violent crimes, and suicides in a metropolitan area. Method: We performed a retrospective study for the year 1999 in a mid-sized city. We included all documented emergent psychiatric visits to the city's psychiatric emergency room. We obtained violence data from the city police department and suicide data from the county medical examiner. Results: The data suggest that total numbers of acts of violence and emergency psychiatry visits are significantly associated with low barometric pressure. Psychiatric inpatient admissions and suicides are not associated with any of the weather variables investigated. Conclusions: While alternate conclusions can be drawn, we propose that the data support the interpretation that low barometric pressure is associated with an increase in impulsive behaviours. Additional investigation is warranted.