Climate Change in Relation to Suicide Rates in Taiwan: A Ten-Year Trend Study

Climate Change in Relation to Suicide Rates in Taiwan: A Ten-Year Trend Study

Background: Climate change has greatly affected the environment, ecology, and economy. However, little is known about whether and how climate change influences mental health. This study used datasets to examine the relationships among various meteorological factors and suicide rates in Taiwan over a 10-year period. Methods: Four sets of data were linked in this study. Descriptive statistics were used to determine distributions of meteorological variables and suicide rates. Multiple logistic regression analyses were conducted annually to examine whether meteorological variables can predict concurrent suicide. Time series analyses were performed to verify whether suicide rate is associated with climate change trends. Results: During the period 1999-2008, there was an increase in the suicide rate in Taiwan, especially among males. The pressure, temperature, relative humidity, and sunshine hours remained relatively stable during this 10-year period, while the frequencies of heavy rainfall, defined as over 500 mm within a single month, increased dramatically after 2004. The concurrent effect of heavy rainfall on suicide rate was significant after 2004. A similar pattern was found on time series analysis. When stratified by sex, the effect was especially salient among females (b = 0.002, p＜0.05). Pressure also had a significant effect on suicide rate (b = -0.191, p＜0.001 for males; b = -0.097, p＜0.0001 for females). Conclusions: With respect to the risk factors of suicide, not only individual level factors, but also macro level factors, such as climate change, have played a role in the increasing suicide rate during the past decade in Taiwan.