The effect of seasonal and meteorological factors on suicide rates in the Lithuanian population in 2001–2021: a case‑crossover study
摘要
The creation and implementation of suicide prevention measures requires an evaluation of the full range of potential risk factors. This study examined the associations between the total number of suicides in the season-specific context and various meteorological parameters in Lithuania as a country of the Boreal region.
MethodsThis study included data on 21,487 cases of suicide in Lithuania from 2001 to 2021. The data were collected from the Register of the Institute of Hygiene. The associations between weather variables and the daily number of suicides were evaluated using a multivariate Poisson regression.
ResultsThe rate ratio (RR) of suicide was observed to be highest in two summer months, June and July (1.35 and 1.36, respectively), compared to January, with the same tendency in both sexes and different ages. Elevated temperature was associated with a significantly higher RR of suicide in the general population, in men, and across all ages. Moreover, a higher number of sunny hours per day was also associated with higher RR in the whole sample, in both sexes and at the youngest and the oldest ages. Higher atmospheric pressure was found to be associated with lower suicide RR in the total sample, in men, and in the youngest and the middle age groups. An average relative humidity (RH) of 50% or more, compared to an average relative humidity < 50%, was associated with a significantly higher RR of suicide in the total sample and in the men’s group.
ConclusionsThere is significant evidence of seasonal effects on suicide. Clinical services in Lithuania should be aware of the risk of suicide on the hot, long summer days, especially among men.