Gender-dependent associations between socioeconomic status and tooth loss in working age people in the Study of Health in Pomerania (SHIP), Germany

Objectives: Individual impact and the effect magnitude of socioeconomic key indicators (income, education and occupation) and of gender on oral health are ambiguous. In primary analyses of cross-sectional data among participants of the Study of Health in Pomerania (north-east Germany), women with low school education and low income were at highest risk for missing teeth, whereas being single was a risk indicator for missing teeth in men. Using the 5-year follow-up of this study, we aimed at verifying these findings and at investigating the gender-dependent impact of key socioeconomic indicators on tooth loss. Methods: The longitudinal data originate from 1971 subjects (1062 women) aged 25-59 enrolled from 1997 to 2001 and again from 2002 to 2006. The effects of marital status, household income, school education and occupational prestige for tooth loss were examined by gender using negative binomial regression analyses. Results: Low education and low income were moderately [relative risks (RR) between 1.6 and 2.0] associated with tooth loss among both women and men, whereas occupational prestige was not. After multiple imputations of missing data, less-educated women with lower income exhibited the highest risk of tooth loss [RR = 3.1; 95% confidence interval (CI) = 1.7-5.5 for <10 years of school education and the lowest income tertile] and tooth loss was more likely in single men (RR = 1.5; 95% CI = 1.0-2.2) than in single women (RR = 0.9; 95% CI = 0.6-1.3). Conclusions: The primary cross-sectional results were partly confirmed. Socioeconomic factors help to explain differences in tooth loss, although the causal pathways are speculative. To improve dental health, the policies should target not only the individual, e. g. oral health promotion, but also an entire population by better education and higher wage employment.