Association between serum antibodies against oral microorganisms and vitamin D deficiency among US adults: A cross-sectional study.

Vitamin D deficiency is common and may contribute to periodontal disease by affecting periodontal pathogens. Most studies analyzing this association have focused mainly on a specific periodontal bacterium (P gingivalis) and have involved relatively small study populations (tens or hundreds of individuals). To address this gap, a sizable, nationally representative adult population was utilized to investigate the association between the prevalence of Vitamin D deficiency and immunoglobulin G (IgG) antibodies to 19 periodontal bacteria using a large, nationally representative population. Drawing from the Third National Health and Nutrition Examination Survey, which constitutes a cross-sectional representation of the noninstitutionalized US population encompassing 33,994 individuals, we incorporated all qualifying participants aged 40 and above. These participants were then categorized into 2 groups according to serum 25-hydroxyvitamin D (25 [OH]D) concentration levels, following the Endocrine Society Clinical Practice Guidelines: Vitamin D deficiency (<75.0 nmol/L) and sufficient (≥75.0 nmol/L). We subsequently excluded individuals without complete records of serum IgG antibodies against periodontal bacteria, resulting in a final analytic sample of 6221 individuals. Using cluster analysis based on the Socransky classification scheme for oral microorganisms, the 19 antibody titers were divided into 4 clusters: Red-Green, Orange-Blue, Yellow-Orange, and Orange-Red. After controlling for lifestyle and demographic factors, no significant correlations were found between any of the clusters and Vitamin D deficiency. However, when analyzing each of the 19 periodontal serum IgG antibodies individually, only P gingivalis antibody levels remained positively associated with Vitamin D deficiency after full adjustment (odds ratio [OR] = 1.049; 95% confidence interval [CI]: 1.008-1.091; P < .05). In contrast, antibodies against A actinomycetemcomitans and E nodatum were inversely associated with Vitamin D deficiency (A actinomycetemcomitans: OR = 0.939; 95% CI: 0.895-0.986; P < .05; E nodatum: OR = 0.947; 95% CI: 0.911-0.985; P < .01). No other significant associations were observed after covariate adjustment. There were no associations between antibody clusters and vitamin D deficiency. However, specific bacteria (P gingivalis, A actinomycetemcomitans, and E nodatum) were associated with vitamin D status.