Seasonal variations of all-cause and cause-specific mortality by age, gender, and socioeconomic condition in urban and rural areas of Bangladesh

International Journal for Equity in Health

Research

Wilfried R Endlicher¹  Katrin Burkart¹  Susanne Breitner²  Alexandra Schneider²  Alexander Krämer³  Mobarak H Khan⁴ 

[1] Department of Geography, Humboldt-Universität zu Berlin, Berlin, German;Helmholtz Zentrum München - German Research Center for Environmental Health, Institute of Epidemiology II, München, Germany;Universität Bielefeld, School of Public Health, Bielefeld, Germany;Universität Bielefeld, School of Public Health, Bielefeld, Germany;Department of Statistics, Jahangirnagar Universtity, Savar, Bangladesh;

关键词: Monsoon Season;    Cold Season;    Statistical Metropolitan Area;    Summer Peak;    Diarrhoeal Disease;   

DOI  :  10.1186/1475-9276-10-32

 received in 2011-01-22, accepted in 2011-08-04,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundMortality exhibits seasonal variations, which to a certain extent can be considered as mid-to long-term influences of meteorological conditions. In addition to atmospheric effects, the seasonal pattern of mortality is shaped by non-atmospheric determinants such as environmental conditions or socioeconomic status. Understanding the influence of season and other factors is essential when seeking to implement effective public health measures. The pressures of climate change make an understanding of the interdependencies between season, climate and health especially important.MethodsThis study investigated daily death counts collected within the Sample Vital Registration System (VSRS) established by the Bangladesh Bureau of Statistics (BBS). The sample was stratified by location (urban vs. rural), gender and socioeconomic status. Furthermore, seasonality was analyzed for all-cause mortality, and several cause-specific mortalities. Daily deviation from average mortality was calculated and seasonal fluctuations were elaborated using non parametric spline smoothing. A seasonality index for each year of life was calculated in order to assess the age-dependency of seasonal effects.ResultsWe found distinctive seasonal variations of mortality with generally higher levels during the cold season. To some extent, a rudimentary secondary summer maximum could be observed. The degree and shape of seasonality changed with the cause of death as well as with location, gender, and SES and was strongly age-dependent. Urban areas were seen to be facing an increased summer mortality peak, particularly in terms of cardiovascular mortality. Generally, children and the elderly faced stronger seasonal effects than youths and young adults.ConclusionThis study clearly demonstrated the complex and dynamic nature of seasonal impacts on mortality. The modifying effect of spatial and population characteristics were highlighted. While tropical regions have been, and still are, associated with a marked excess of mortality in summer, only a weakly pronounced secondary summer peak could be observed for Bangladesh, possibly due to the reduced incidence of diarrhoea-related fatalities. These findings suggest that Bangladesh is undergoing an epidemiological transition from summer to winter excess mortality, as a consequence of changes in socioeconomic conditions and health care provision.

【 授权许可】

CC BY   
© Burkart et al; licensee BioMed Central Ltd. 2011