Determinants of Hardcore Smoking in a MULTI-ETHNIC Study of Cigarette Smokers in Singapore.

Smokers who are resistant to quitting are not well studied in Asia, particularly in multi-ethnic populations. We compared the characteristics of hardcore smokers in Singapore, a multi-ethnic Asian population, with other daily smokers, and investigated the role of ethnicity as an effect modifier on identified determinants, including cigarette flavor preferences, using cross-sectional data from Singapore Smokers' Survey (n = 1,501). Multivariable logistic regression was used to assess the association. 22.8% of adult daily smokers were hardcore smokers. Novel findings on hardcore smokers' preference for regular flavored cigarettes (AOR = 1.54; 95%CI: 1.14, 2.07) suggest there is room for interventions among hardcore smokers through regulation of cigarette flavors and nicotine content. Although ethnicity was not a significant factor, it was an effect modifier with peers' disapproval of smoking (p-value for interaction = 0.024), significantly lowering odds of Malays being hardcore smokers (stratified odds ratio, AOR stratified, Malay = 0.35; CI: 0.17, 0.71), but not Chinese (AOR stratified, Chinese = 1.27; CI: 0.70, 2.42) and Indian smokers (AOR stratified, Indian = 0.62; CI: 0.18, 2.28), suggesting that smoking cessation policies utilizing social norm change strategies may be more effective when tailored to the differing roles of peer norms among different ethnic groups, in Singapore and other multi-ethnic Asian populations.