The effect of meteorological variables on suicide.

We aimed to reveal the relationship between the meteorological variables and suicide rates (completed suicides and suicide attempts) independently of the seasonal cycle and holiday effects. This is an observational retrospective study. We collected the data on age, gender, and suicide method of all suicide cases transferred to hospitals from the scene by emergency medical services as well as those cases in which the victim died on the scene between January 1, 2017 and June 30, 2019. We also collected data on maximum, minimum, and average temperatures (°C), average humidity (%), and average actual pressure (hPa) measured daily in Ankara. The total number of cases due to suicide between the given dates was 6777. The suicide method in 60.1% of the cases was drug poisoning, which was the most common suicide method. Investigating the effect of meteorological variables on suicide cases (suicide attempts and completed suicides), the present study found that after smoothing the effect of the day of the week and seasonality, an increase in the minimum temperature on the day of the application by 1 unit (1°C degree) leads to an increase in the number of suicides by 0.01 point (0.01 ± 0.005, p = 0.046). There was no significant change in the variables other than the minimum temperature. We believe that the results of the present study will contribute to growing body literature about the epidemiology of suicide. We also believe that there is a need for large-scale studies that include individual data to reveal causality.