Socioeconomic disparities in household secondhand smoke exposure among non-smoking adolescents in the Republic of Korea.

This nationally representative study examined (a) gender and age differences in household secondhand smoke exposure (HSHSE) and (b) associations between socioeconomic status (SES) and HSHSE among non-smoking Korean adolescents. Two subsamples were analysed: males (n = 25,648) and females (n = 30,240). The HSHSE measures were incidence of HSHSE (yes/no) and number of days of HSHSE (1-7 days); the SES measures were parental education, perceived economic status, and family wealth. For the first aim, chi-square test, t-test, and bivariate negative binomial regression analysis were performed; For the second aim, multivariate logistic regression and negative binomial regression analyses were performed. The incidence and number of days of HSHSE were significantly higher among females (32.35% and 3.48 days) than males (26.83% and 3.08 days). The HSHSE incidence was significantly higher among younger adolescents (23.32% to 31.08% of males and 26.58% to 37.03% of females). Lower SES was associated with (a) greater odds of HSHSE (odds ratio: 1.12-1.58 among males and 1.19-1.85 among females) and (b) greater incidence rates of HSHSE (incidence rate ratio: 1.05-1.17 among males and 1.10-1.14 among females). Efforts should be made to decrease HSHSE among adolescents, particularly low-SES youth.