Study of suicide trends and some kind of factor in several Japan’s prefectures: For the future study in the Republic of Kazakhstan

Background: Many countries with high suicide rates may also experience heavy yearly snowfalls. We speculated that Japan's prefectures that have high suicide rates may be in regions with heavy snowfall. Although many suicide-related factors have been studied, few investigations have examined the effects of snow on suicide. Objective: We investigated regions of Japan along the Sea of Japan (at Japan's west coast) that regularly experience heavy and long-term snowfall. It is also the purpose of applying this perspective to study in the Republic of Kazakhstan. Materials and Methods: We determined the annual suicide rates in 11 prefectures (Hokkaido, Aomori, Akita, Yamagata, Niigata, Toyama, Ishikawa, Fukui, Tottori, Shimane, and Yamaguchi) along the Sea of Japan with heavy snowfall during the period from 1994 to 2019. We obtained each prefecture's annual maximum depth of snow cover and the annual number of days with snow during the same period. We analyzed the correlations between the suicide rates and these two aspects of snowfall. Results: The maximum depth of snow cover and the number of days with snow were not significantly correlated with the suicide rate in any of the 11 prefectures. There was no clear link between the effects of the snowfall and suicide. The relationship between multiple factors including snow and suicide merits further research. Conclusions: Various weather phenomena including snow can cause mental fatigue and poor mental health and could potentially contribute to suicide, and thus aspects of weather and their effects on mental health should be investigated. The public, members of the local community, government agencies, meteorological agencies, medical personnel, and organizations and professionals involved in suicide prevention should work together when necessary to explore suicide prevention. In the future, we are going to perform the study of this side in the Republic of Kazakhstan