Another ecologic study attempting to infer associations with very weak correlations. Would nonconsumption of food be associated with a lower prevalence of elevated dental caries?
Sanders AE, Slade GD. Blood Lead Levels and Dental Caries in U.S. Children Who Do Not Drink Tap Water. American journal of preventive medicine. 2017 Nov 18. pii: S0749-3797(17)30495-6. doi: 10.1016/j.amepre.2017.09.004.
INTRODUCTION: This study’s purpose is to determine whether nonconsumption of tap water is associated with lower prevalence of elevated blood lead levels and higher prevalence of dental caries in children and adolescents.
METHODS: Cross-sectional data from the National Health and Nutrition Examination Survey 2005-2014 recorded drinking water source (n=15,604) and blood lead levels (n=12,373) for participants aged 2-19 years, and dental caries experience for the 2011-2014 subset (n=5,677). The threshold for elevated blood lead level was ≥3 μg/dL. A binary outcome indicated presence or absence of dental caries experience. Multivariable generalized linear models estimated adjusted prevalence ratios with 95% confidence limits.
RESULTS: In analysis conducted in 2017, 15% of children and adolescents did not drink tap water, 3% had elevated blood lead levels ≥3 μg/dL, and 50% had dental caries experience. Children and adolescents who did not drink water were less likely than tap water drinkers to have an elevated blood lead level (adjusted prevalence ratios=0.62, 95% confidence limits=0.42, 0.90). Nonconsumers of tap water were more likely to have dental caries (adjusted prevalence ratios=1.13, 95% confidence limits=1.03, 1.23). Results persisted after adjustment for other covariates and using a higher threshold for elevated blood lead level.
CONCLUSIONS: In this nationally representative U.S. survey, children and adolescents who did not drink tap water had lower prevalence of elevated blood lead levels and higher prevalence of dental caries than those who drank tap water.