Diminished Returns of Income Against Cigarette Smoking Among Chinese Americans.

Introduction: Although educational attainment and income are protective against tobacco use, Marginalization-related Diminished Returns (MDRs) theory posits that the protective effects of socioeconomic status (SES) indicators may be smaller for marginalized groups than mainstream social groups. We aimed to compare the effects of educational attainment and income on current smoking status of Chinese American and European American adults.

Methods: Data came from the National Health Interview Survey (NHIS - 2015). A total number of 28081 individuals entered our analysis. This included 420 Chinese Americans and 27661 European Americans. The independent variables were educational attainment (years of schooling) and annual income. The dependent variable was current established smoking status. Age, gender, region, and marital status were covariates. Ethnicity (Chinese American vs. European American) was the moderator.

Results: Overall, educational attainment and income were inversely associated with the odds of current established smoking. Ethnicity showed a significant interaction with income but not educational attainment. This finding suggested that the protective effect of income, but not educational attainment, on odds of current established smoking might be smaller for Chinese Americans than European Americans.

Conclusions: While educational attainment reduces the odds of current established smoking, high-income Chinese Americans remain at high risk of smoking due to a phenomenon called MDRs. In fact, high income is associated with greater smoking prevalence in Chinese Americans, rather than less. To reduce ethnic disparities in tobacco use, we need to go beyond SES inequalities by addressing structural causes of higher than expected risk of smoking in high SES ethnic minorities.