Early life-course socioeconomic position, adult work-related factors and oral health disparities: cross-sectional analysis of the J-SHINE study

OBJECTIVES: We examined the association between socioeconomic position (SEP) and oral health, and the associations of economic difficulties in childhood and workplace-related factors on these parameters. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 3201 workers aged 25–50 years, living in and around Tokyo, Japan, from the J-SHINE (Japanese study of Stratification, Health, Income, and Neighborhood) study. The response rate was 31.6%. OUTCOME MEASURES: Self-rated oral health (SROH)—A logistic regression model was used to estimate ORs for the association between poor SROH and each indicator of SEP (annual household income, wealth, educational attainment, occupation and economic situation in childhood). Multiple imputation was used to address missing values. RESULTS: Each indicator of SEP, including childhood SEP, was significantly inversely associated with SROH, and all of the workplace-related factors (social support in the workplace, job stress, working hours and type of employment) were also significantly associated with SROH. Compared with professionals, blue-collar workers had a significantly higher OR of poor SROH and the association was substantially explained by the workplace-related factors; ORs ranged from 1.44 in the age-adjusted and sex-adjusted model to 1.18 in the multivariate model. Poverty during childhood at age 5 and at age 15 was associated with poorer SROH, and these two factors seemed to be independently associated with SROH. CONCLUSIONS: We found oral health disparity across SEP among workers in Japan. Approximately 60% of the association between occupation and SROH was explained by job-related factors. Economic difficulties during childhood appear to affect SROH in adulthood separately from sex, age and the current workplace-related factors.