Is childhood oral health the 'canary in the coal mine' for poor adult general health? Findings from two New Zealand birth cohort studies.

Objectives: This study aimed to investigate whether childhood dental caries was associated with self-reported general health in midlife.
Methods: We used data on childhood oral health (caries experience) and adult self-reported general health from two New Zealand longitudinal birth cohorts, the Dunedin Multidisciplinary Health and Development Study (n = 922 and n = 931 at ages 5 and 45 years, respectively), and the Christchurch Health and Development Study (n = 1048 and n = 904 at ages 5 and 40 years, respectively). We used generalized estimating equations to examine associations between age-5 dental caries and self-rated general health and the number of self-reported physical health conditions at ages 45/40 (diagnosed by a doctor or health professional, n = 14 conditions among both cohorts). Covariates included known risk factors for poor health (SES, IQ, perinatal complications), and personality style, which is known to affect subjective health ratings.
Results: Incidence rate ratios for 'Excellent' self-rated health were lower among those who had high experience of dental caries as children than those who had not in both, the Dunedin (IRR, 0.76; 95% CI, 0.50, 1.14) and Christchurch studies (IRR, 0.69; 95% CI, 0.47, 1.00). Childhood dental caries was not associated with the number of self-reported physical health conditions in midlife, in either cohort. Dunedin Study members who at age 5 were not caries-free or whose parents rated their own or their child's oral health as poor were less likely to report 'Excellent' self-rated general health at age 45 than those who were caries-free and whose parents did not give a 'poor' rating (IRR, 0.69; 95% CI, 0.49, 0.97).
Conclusions: Five-year-olds with greater caries experience were more likely to have poorer self-rated general health by midlife. Beyond this longitudinal association, future research should examine whether childhood dental caries is associated with objective/biological markers of physical health and whether it may have utility as an early indicator for poor general health in adulthood.
(© 2022 The Authors. Community Dentistry and Oral Epidemiology published by John Wiley & Sons Ltd.)