The intensity of the "urban heat island effect (UHIE)" is statistically significant in association with suicides among the elderly in greater Taipei, according to the results of a recent study.
Published in the August issue of the Taiwan Journal of Public Health, the study found that for every 1-degree Celsius increase in the intensity of UHIE, the suicide mortality rate among the elderly population rises by 5.49 percent.
The study investigated the correlation between UHIE and the suicide mortality rate among people aged 65 and above in metropolitan Taipei from 2000 to 2008, using geographic information and statistical analysis.
It was jointly conducted by researchers from National Chiayi University, National Yang-Ming University, National Chen Kung University, National Health Research Institutes, and Academia Sinica, Taiwan's top research institution.
Researchers used data collected from weather stations and a Kriging interpolation method to estimate the UHIE intensity in each township, according to the abstract of the study.
They then examined the spatial and temporal trends in UHIE and elderly suicides, and assessed the spatial cluster effect of elderly suicides. Finally, they assessed the association between UHIE and elderly suicides, after adjusting for confounders such as air temperature and precipitation, as well as income tax, education level, marital status and gender ratio of the elderly population.
Wu Chih-da (???), one of the co-authors of the study and an assistant professor from National Chiayi University's Department of Forestry and Natural Resources, said Saturday that temperatures have been an important factor in the suicides.
The increase in temperatures caused by UHIE in Taiwan can be serious, as Taiwan is densely populated and its population and industries are concentrated in cities, where crowded concrete structures make it hard for heat to dissipate, Wu said.
He cited statistics saying that those aged 65 and above have a much higher suicide mortality rate than other age groups. Between 2000 and 2008, 1,785 people aged 65 and above have died of suicide in Taipei and New Taipei, Wu said.
He said Taiwan's metropolitan areas are in need of more green spaces and parks, which could help reduce UHIE.
Liu Mu-en (???), a physician from the Department of Psychiatry of Taipei Veterans General Hospital, said studies have pointed out that peoples' moods can be affected by the weather, and average people become more irritable during hot weather.
He advised the elderly to stay in air-conditioned rooms or visit malls or other public places with air conditioning when temperatures become too hot.
The Taiwan Journal of Public Health is published bimonthly by the Taiwan Public Health Association, an academic organization that focuses on the advancement of public health.
Source: Focus Taiwan