International study of temperature, heat and urban mortality: the 'ISOTHURM' project

Date

2008

Authors

McMichael, Anthony
Wilkinson, Paul
Kovats, R Sari
Pattenden, Sam
Hajat, Shakoor
Armstrong, Ben
Vajanapoom, Nitaya
Niciu, Emilia M
Mahomed, Hassan
Kingkeow, Chamnong

Journal Title

Journal ISSN

Volume Title

Publisher

Oxford University Press

Abstract

Background: This study describes heat- and cold-related mortality in 12 urban populations in low- and middle-income countries, thereby extending knowledge of how diverse populations, in non-OECD countries, respond to temperature extremes. Methods: The cities were: Delhi, Monterrey, Mexico City, Chiang Mai, Bangkok, Salvador, São Paulo, Santiago, Cape Town, Ljubljana, Bucharest and Sofia. For each city, daily mortality was examined in relation to ambient temperature using autoregressive Poisson models (2- to 5-year series) adjusted for season, relative humidity, air pollution, day of week and public holidays. Results: Most cities showed a U-shaped temperature-mortality relationship, with clear evidence of increasing death rates at colder temperatures in all cities except Ljubljana, Salvador and Delhi and with increasing heat in all cities except Chiang Mai and Cape Town. Estimates of the temperature threshold below which cold-related mortality began to increase ranged from 15°C to 29°C; the threshold for heat-related deaths ranged from 16°C to 31°C. Heat thresholds were generally higher in cities with warmer climates, while cold thresholds were unrelated to climate. Conclusions: Urban populations, in diverse geographic settings, experience increases in mortality due to both high and low temperatures. The effects of heat and cold vary depending on climate and non-climate factors such as the population disease profile and age structure. Although such populations will undergo some adaptation to increasing temperatures, many are likely to have substantial vulnerability to climate change. Additional research is needed to elucidate vulnerability within populations.

Description

Keywords

Keywords: climate change; epidemiology; estimation method; high temperature; low income population; low temperature; mortality; urban climate; urban population; vulnerability; air pollution; article; Brazil; Bulgaria; Chile; city; cold climate; controlled study; en Cities; Climate; Epidemiology; Heat; Low income populations; Meteorological factors; Mortality; Temperature

Citation

Source

International Journal of Epidemiology

Type

Journal article

Book Title

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Restricted until

2037-12-31