Cross-national comparison of socioeconomic inequalities in obesity in the United States and Canada

International Journal for Equity in Health

Ichiro Kawachi³  Rachel Loopstra²  Quynh C. Nguyen⁵  Rashida Brown⁴  Arjumand Siddiqi¹ 

[1] Department of Health Behavior, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, Chapel Hill, NC, US;Department of Sociology, University of Oxford, Manor Road Building, Manor Road, Oxford OX1 3UQ, UK;Department of Society, Human Development, and Health, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Kresge Building 7th Floor, Boston 02115, MA, US;Division of Epidemiology, School of Public Health, University of California, Berkeley, 101 Haviland Hall, Berkeley 94720-7358, CA, US;Department of Health Promotion and Education, College of Health, University of Utah, 1901 E. So. Campus Drive, #2120, Salt Lake City 84112, UT, US

关键词: United States;    Canada;    Obesity;    Health inequalities;    Socioeconomic status;   

Others  :  1231280
DOI  :  10.1186/s12939-015-0251-2

 received in 2015-02-17, accepted in 2015-10-19,  发布年份 2015

【 摘 要 】

Introduction

Prior cross-national studies of socioeconomic inequalities in obesity have only compared summary indices of inequality but not specific, policy-relevant dimensions of inequality: (a) shape of the socioeconomic gradient in obesity, (b) magnitude of differentials in obesity across socioeconomic levels and, (c) level of obesity at any given socioeconomic level. We use unique data on two highly comparable societies – U.S. and Canada - to contrast each of these inequality dimensions.

Methods

Data came from the 2002/2003 Joint Canada/U.S. Survey of Health. We calculated adjusted prevalence ratios (APRs) for obesity (compared to normal weight) by income quintile and education group separately for both nations and, between Canadians and Americans in the same income or education group.

Results

In the U.S., every socioeconomic group except the college educated had significant excess prevalence of obesity. By contrast in Canada, only those with less than high school were worse off, suggesting that the shape of the socioeconomic gradient differs in the two countries. U.S. differentials between socioeconomic levels were also larger than in Canada (e.g., PR quintile 1 compared to quintile 5 was 1.82 in the U.S. [95 % CI: 1.52-2.19] but 1.45 in Canada [95 % CI: 1.10-1.91]). At the lower end of the socioeconomic gradient, obesity was more prevalent in the U.S. than in Canada.

Conclusions

Our results suggest there is variation between U.S. and Canada in different dimensions of socioeconomic inequalities in obesity. Future research should examine a broader set of nations and test whether specific policies or environmental exposures can explain these differences.

【 授权许可】

   
2015 Siddiqi et al.

【 图 表 】

Fig. 1.

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