Intergenerational 'mismatch' and adiposity in a developing population: The Guangzhou biobank cohort study

Intergenerational 'mismatch' between maternal and adult environments, common in developing economies, has been hypothesized as contributing to obesity. In a rapidly developing population, we examined whether maternal conditions, proxied by maternal literacy, were associated with adult adiposity, proxied by body mass index (BMI) and waist-hip ratio (WHR) and whether these associations were modified by later life conditions, proxied by socio-economic position (SEP) at three life stages. We also examined if maternal conditions had sex-specific associations with adult adiposity. In a cross-sectional study of 19,957 adults (≥50 years) from the Guangzhou Biobank Cohort Study (phases 2 and 3 in 2005-2008), we used multivariable linear regression to assess the association of maternal literacy with BMI and WHR, and whether the associations varied with sex, age or SEP. The adjusted association of maternal literacy with WHR varied with sex. In women, but not men, maternal illiteracy was associated with higher WHR and BMI, adjusted for age; these associations remained, although attenuated, after adjusting for lifestyle, life course SEP and paternal literacy. There was little evidence that associations varied with SEP at any stage, although continuity of poor conditions into early life may have exacerbated the association of maternal illiteracy with higher WHR in women. Poor maternal conditions in developing populations may increase vulnerability to adiposity in women. Whether such sex-specific intergenerational effects are driven by epigenetics, maternal sex hormones or other mechanisms, remains to be determined. However, mismatched maternal and later life conditions do not appear to be associated with adiposity. Our findings, although preliminary, imply that a transient epidemic of obesity may occur in the first generation of women who experience economic development.