Socioeconomic inequality in smoking in low-income and middle-income countries: results from the World Health Survey

PLoS One. 2012;7(8):e42843. doi: 10.1371/journal.pone.0042843. Epub 2012 Aug 29.


Objectives: To assess the magnitude and pattern of socioeconomic inequality in current smoking in low and middle income countries.

Methods: We used data from the World Health Survey [WHS] in 48 low-income and middle-income countries to estimate the crude prevalence of current smoking according to household wealth quintile. A Poisson regression model with a robust variance was used to generate the Relative Index of Inequality [RII] according to wealth within each of the countries studied.

Results: In males, smoking was disproportionately prevalent in the poor in the majority of countries. In numerous countries the poorest men were over 2.5 times more likely to smoke than the richest men. Socioeconomic inequality in women was more varied showing patterns of both pro-rich and pro-poor inequality. In 20 countries pro-rich relative socioeconomic inequality was statistically significant: the poorest women had a higher prevalence of smoking compared to the richest women. Conversely, in 9 countries women in the richest population groups had a statistically significant greater risk of smoking compared to the poorest groups.

Conclusion: Both the pattern and magnitude of relative inequality may vary greatly between countries. Prevention measures should address the specific pattern of smoking inequality observed within a population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Algorithms
  • Female
  • Global Health
  • Health Status Disparities
  • Health Surveys*
  • Humans
  • Male
  • Middle Aged
  • Poisson Distribution
  • Poverty*
  • Risk
  • Sex Factors
  • Smoking / economics*
  • Smoking / epidemiology*
  • Socioeconomic Factors

Grants and funding

This study was funded by WHO. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.