Relation between temperature and suicide mortality in Japan in the presence of other confounding factors using time-series analysis with a semiparametric approach.

OBJECTIVES: The objective of this study was to assess the relation between temperature and suicide mortality in Japan using time series analysis with a semiparametric approach. METHODS: We analyzed the relation between daily fluctuations in suicide mortality and maximum temperatures for all regions in Japan over the period of time from 1972 to 1995 using a generalized additive model. The model controls for the time trend, season, selected meteorological parameters, day of the week, and holiday. Adjustment was based using penalized splines and the decision on the amount of smoothness was based on minimizing the unbiased risk estimation criterion. RESULTS: The results show that suicide mortality in Japan has a seasonal character and it varies from year to year, with the highest occurrence in April, as well as in the first part of the week, especially on Mondays and Tuesdays. As for the day of the week, there were only few suicide cases on Saturdays and holidays. We found that for all regions in Japan when temperature increased the suicide mortality increased on the same day (lag = 0). Analysis by method of suicide showed that when temperature increased mortality significantly increased only for suicide by a violent method. The pattern of the relation for other methods remained unclear. CONCLUSIONS: This study suggests that an increase in temperature has a short-term effect on suicide mortality in Japan.

A multi-scale health impact assessment of air pollution over the 21st century.

BACKGROUND: Ozone and PM2.5 are current risk factors for premature death all over the globe. In coming decades, substantial improvements in public health may be achieved by reducing air pollution. To better understand the potential of emissions policies, studies are needed that assess possible future health impacts under alternative assumptions about future emissions and climate across multiple spatial scales. METHOD: We used consistent climate-air-quality-health modeling framework across three geographical scales (World, Europe and Ile-de-France) to assess future (2030-2050) health impacts of ozone and PM2.5 under two emissions scenarios (Current Legislation Emissions, CLE, and Maximum Feasible Reductions, MFR). RESULTS: Consistently across the scales, we found more reductions in deaths under MFR scenario compared to CLE. 1.5 [95% CI: 0.4, 2.4] million CV deaths could be delayed each year in 2030 compared to 2010 under MFR scenario, 84% of which would occur in Asia, especially in China. In Europe, the benefits under MFR scenario (219000 CV deaths) are noticeably larger than those under CLE (109,000 CV deaths). In Ile-de-France, under MFR more than 2830 annual CV deaths associated with PM2.5 changes could be delayed in 2050 compared to 2010. In Paris, ozone-related respiratory mortality should increase under both scenarios. CONCLUSION: Multi-scale HIAs can illustrate the difference in direct consequences of costly mitigation policies and provide results that may help decision-makers choose between different policy alternatives at different scales.