Title: 2368 - Is Vitamin D a Modifiable Risk Factor for Dental Caries?
Serena Dodhia (Presenter)
University of Bristol
Steve Thomas, University of Bristol
Nicola West, University of Bristol
Nicholas Timpson, University of Bristol
Tom Dudding, University of Bristol
Simon Haworth, University of Bristol
Objectives: Prior observational studies have reported that higher levels of vitamin D are associated with decreased caries risk in children. However, these studies are prone to bias and confounding, therefore, do not provide causal inference. Genetic variants associated with a risk factor of interest can be used as proxies, in a Mendelian Randomisation (MR) analysis, to test for causal association with an outcome. The objective was to use MR to test for causal association between 25-hydroxyvitamin D (25(OH)D): the commonly measured vitamin D metabolite in the blood, and risk of caries.
Methods: Five single nucleotide polymorphisms (SNPs) were identified as proxies for 25(OH)D in a published genome-wide association study (GWAS). Data on caries was available in the primary dentition (17,035 children, aged 3-12 years) and permanent dentition (13,386 children, aged 6-18 years). A sensitivity analysis also examined the effects of 25(OH)D on having dentures (a non-specific measure of dental status) available in 461,106 adults (aged 38-72 years). The relationship between 25(OH)D and these traits was calculated separately for each SNP then combined using inverse variance weighted meta-analyses.
Results: In MR analyses, the odds ratio (OR) per one standard deviation increase in log-transformed 25(OH)D was 0.79 (95% confidence interval (CI):0.50,1.24; P=0.30) for caries in primary teeth, 0.84 (95% CI:0.53,1.34; P=0.46) for caries in permanent teeth and 1.04 (95% CI:0.95,1.13; P=0.43) for having dentures in the sensitivity analysis.
Conclusions: The MR derived effect estimates in paediatric populations are directionally consistent with observational associations. Whilst this suggests 25(OH)D may be causally protective against caries with a clinically relevant effect size, the wide confidence intervals indicate a possibility that 25(OH)D could have no effect. Therefore, larger sample sizes are required to resolve this scientific and public health question. Despite potential effects on caries onset in children, the MR estimate suggests 25(OH)D does not prevent having ‘dentures’ in adulthood.
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE