Association between adult height and tooth loss in a representative sample of Koreans

Objectives Evidence suggests that taller individuals have better health than that of shorter individuals. However, evidence for links to tooth loss is scarce. The aim of this study was to examine the association between adult height and tooth loss and to examine the roles of covariates in explaining the association in different birth cohorts in Korea. Methods Using data from the Fourth and Fifth Korea National Health and Nutritional Examination Survey (KNHANES IV and V), the subjects were grouped into two birth cohorts based on their historical context: born from 1920 to 1945 and 1946 to 1962. The dependent variables were loss of 8 or more teeth and total tooth loss (edentulism), while the independent variable was the height quartile. Demographic factors (survey year, age, and gender), early childhood/adult socioeconomic status (SES) (father's education, own education, income, and place of residence), health behaviors (cigarette smoking, binge drinking, frequency of toothbrushing, and regular dental visit), and health problems (diabetes and hypertension) were included in a series of analytical models. Results The survey year-, age-, and gender-adjusted prevalence ratios (PR) of the loss of 8 or more teeth for the shortest quartile were 1.23 (95% confidence intervals, CI: 1.13-1.35) for the 1920-1945 birth cohorts and 1.39 (95% CI: 1.20-1.62) for the 1946-1962 birth cohorts. The PRs for edentulousness were 1.64 (95% CI: 1.34-2.02) for the 1920-1945 birth cohorts and 2.26 (95% CI: 1.31-3.91) for the 1946-1962 birth cohorts. These associations were moderately attenuated after adjusting for own education but still significant in the fully adjusted models. After full adjustment for the covariates, those in the shortest height quartiles in the relatively young birth cohorts (1946-1962 birth cohorts) had a 1.93 (95% CI: 1.09-3.43) times greater prevalence of edentulism than that of their tallest counterparts. Conclusions Given that adult height reflects early-life conditions, independent associations between height and tooth loss support the view that early-life circumstances significantly influence oral health outcomes in later life.