Overcoming confounding of race with socio-economic status and segregation to explore race disparities in smoking

Aims: We examined the nature of racial disparities in smoking status within a sample that accounts for two major confounding factors in health disparities research - racial segregation and socio-economic status. Also, we sought to determine the generalizability of our sample. Design and setting: Cross-sectional study based on data from the Exploring Health Disparities in Integrated Communities Study in south-west Baltimore, MD (EHDIC-SWB) and a subsample of respondents in the 2002 National Health Interview Survey (NHIS) that was matched to EHIDC-SWB. The final matched data set sample size was 2948 adults (1474 EHDIC-SWB; 1474 matched NHIS). Measurements: Our outcome variables were life-time and current smoking status and number of cigarettes smoked daily. Independent variables include race, age gender, educational attainment and income. Findings: In the adjusted models, whites had greater odds than blacks of current smoking and reported smoking more cigarettes in the EHDIC-SWB sample, but there were no race differences in current smoking status or in the number of cigarettes smoked per day in the NHIS. The prevalence rates for both life-time and current smoking were substantially greater in the EHDIC-SWB sample, but in comparisons of blacks and whites across samples we found that the magnitude of the difference between the samples was greatest for whites. Conclusions: Unadjusted national estimates of race disparities as reported in national reports may be biased because of differential risk exposure among people of different race groups. Race differences in social and environmental contexts account partially for racial differences in smoking patterns.