Weight of nations: a socioeconomic analysis of women in low- to middle-income countries.
BACKGROUND
The increasing trend in body mass index (BMI) and overweight in rapidly developing economies is well recognized.


OBJECTIVE
We assessed the association between socioeconomic status and BMI and overweight in low- to middle-income countries.


METHODS
We conducted a cross-sectional analysis of nationally representative samples of 538,140 women aged 15-49 y drawn from 54 Demographic and Health Surveys conducted between 1994 and 2008. BMI, calculated as weight in kilograms divided by height squared in meters, was specified as the outcome, and a BMI (in kg/m(2)) of ≥25 was additionally specified to model the likelihood of being overweight. Household wealth and education were included as markers of individual socioeconomic status, and per capita Gross Domestic Product (pcGDP) was included as a marker of country-level economic development.


RESULTS
Globally, a one-quartile increase in wealth was associated with a 0.54 increase in BMI (95% CI: 0.50, 0.64) and a 33% increase in overweight (95% CI: 26%, 41%) in adjusted models. Although the strength of this association varied across countries, the association between wealth and BMI and overweight was positive in 96% (52 of 54) of the countries. Similar patterns were observed in urban and rural areas, although SES gradients tended to be greater in urban areas. There was a positive association between pcGDP and BMI or overweight, with only weak evidence of an interaction between pcGDP and wealth.


CONCLUSIONS
Higher BMI and overweight remain concentrated in higher socioeconomic groups, even though increasing BMI and overweight prevalence are important global public concerns.
Department of Society, Human Development and Health, Harvard School of Public Health, Boston, MA 02115, USA. svsubram@hsph.harvard.edu
S V
SV
Subramanian
Jessica M
JM
Perkins
Emre
E
Özaltin
George
G
Davey Smith
D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D003906:Developing Countries; D005260:Female; D014943:Global Health; D059066:Gross Domestic Product; D006306:Health Surveys; D006801:Humans; D007182:Income; D008875:Middle Aged; D009765:Obesity / Q000191:economics* / Q000453:epidemiology; D015995:Prevalence; D012424:Rural Population; D012959:Socioeconomic Factors; D014505:Urban Population; D055815:Young Adult