The influence of the Foehn wind (Halny) on the occurrence of suicide in the Tatra Mountains, 1999–2014

Introduction In the dawn of increasing interest in climate changes, including extreme weather events, e.g. the Foehn winds, and their influence on public health, it is of great importance to understand their role in suicide. Objectives The association between suicides in the Tatra Mountains, Poland from 1999 to 2014 and the Foehn wind (called Halny in this region) was examined. The belief that suicides are affected by Halny seems to be firmly rooted in local language and culture. Aims The purpose of the study was to assess the Halny wind as a suicide risk factor. Method Data concerning all suicides in the region were included. Meteorological data were derived every three hours during the period of the study. Halny was defined as a complex of interacting meteorological conditions. The two days preceding and following the wind were recognized as the period of the Foehn influence (FI). The probability of suicide in the presence of Halny and during the FI period was calculated. Results From 1st January 1999 to 31 December 2014 (5844 days), 210 consecutive suicides were registered. The number of suicides in men was markedly higher than in women. Halny did not change the overall probability of suicide. However, the presence of Halny modified the suicide risk according to the season ( P  = 0.00095, two-way ANOVA test). The FI periods appeared to increase suicide risk in summer and autumn. Conclusion Halny may contribute to the increased suicide risk in summer and autumn. It should be taken into account in suicide preventive interventions in this region.