Temperature Variation and heat wave and cold spell impacts on years of life lost among the urban poor population of Nairobi, Kenya
International Journal of Environmental Research and Public Health
African Population and Health Research Center, P.O. Box 10787-00100, Nairobi, Kenya; Department of Public Health and Clinical Medicine, Epidemiology and Global Health, Umeå University, Umeå, Sweden
Weather extremes are associated with adverse health outcomes, including mortality. Studies have investigated the mortality risk of temperature in terms of excess mortality, however, this risk estimate may not be appealing to policy makers assessing the benefits expected for any interventions to be adopted. To provide further evidence of the burden of extreme temperatures, we analyzed the effect of temperature on years of life lost (YLL) due to all-cause mortality among the population in two urban informal settlements. YLL was generated based on the life expectancy of the population during the study period by applying a survival analysis approach. Association between daily maximum temperature and YLL was assessed using a distributed lag nonlinear model. In addition, cold spell and heat wave effects, as defined according to different percentiles, were investigated. The exposure-response curve between temperature and YLL was J-shaped, with the minimum mortality temperature (MMT) of 26 °C. An average temperature of 21 °C compared to the MMT was associated with an increase of 27.4 YLL per day (95% CI, 2.7–52.0 years). However, there was no additional effect for extended periods of cold spells, nor did we find significant associations between YLL to heat or heat waves. Overall, increased YLL from all-causes were associated with cold spells indicating the need for initiating measure for reducing health burdens. © 2015 by the authors; licensee MDPI, Basel, Switzerland.
climate effect; environmental factor; health geography; health impact; informal settlement; mortality; survival; temperature gradient; urban population; Article; cause of death; cold injury; cold spell; controlled study; environmental impact; environmental monitoring; environmental temperature; heat wave; human; Kenya; life expectancy; mortality; outcome assessment; physical phenomena; social status; survival; temperature sensitivity; temperature variation; thermal analysis; urban area; weather; Kenya; Nairobi [Kenya]; Nairobi [Nairobi (CNT)]