American Journal of Epidemiology Advance Access originally published online on December 4, 2007
American Journal of Epidemiology 2008 167(4):419-428; doi:10.1093/aje/kwm329
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ORIGINAL CONTRIBUTIONS |
Life-Course Origins of Social Inequalities in Metabolic Risk in the Population of a Developing Country
1 Department of Community Medicine and School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
2 Guangzhou Occupational Diseases Prevention and Treatment Centre, Guangzhou No. 12 Hospital, Guangzhou, China
3 Department of Public Health and Epidemiology, University of Birmingham, Birmingham, United Kingdom
Correspondence to Professor T. H. Lam, Department of Community Medicine and School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China (e-mail: commed{at}hkucc.hku.hk).
Received for publication July 9, 2007. Accepted for publication October 8, 2007.
In countries that have been industrialized for a long time, but not always elsewhere, low socioeconomic position (SEP) is associated with ischemic heart disease in men. The authors hypothesized that socioeconomic development could, via pubertal sex steroids, promote an atherogenic lipid profile and body shape in men but not in women. Therefore, they examined the associations of SEP with ischemic heart disease risk in a developing-country population. The authors used multivariable regression to examine the associations of SEP with the metabolic syndrome and its components in 9,746 Chinese adults aged 
50 years from the Guangzhou Biobank Cohort Study, phase 2, recruited in 2005–2006. After adjustment for age, smoking, alcohol use, and physical activity, high SEP at each of three life stages, proxied by parental possessions in childhood, education, and longest held-occupation, was inversely associated with the metabolic syndrome in women but not in men. Higher SEP in men was associated with lower pulse pressure and fasting plasma glucose level but also with greater waist circumference and a lower high density lipoprotein cholesterol level. With socioeconomic development, diet-related hormonal changes at puberty may outweigh the usual protective effect of social advantage in men, with corresponding implications for boys currently undergoing the nutrition transition in the developing world.
China; developing countries; gonadal steroid hormones; metabolism; myocardial ischemia; risk factors; social class
Abbreviations: CI, confidence interval; HDL, high density lipoprotein; OR, odds ratio; SEP, socioeconomic position