Clinical attachment loss is cross-sectionally associated with elevated glucose among adults without diabetes.

AIM: We investigated whether periodontal measures are cross-sectionally associated with prediabetes and cardiometabolic biomarkers among non-diabetic younger adults. MATERIALS AND METHODS: One thousand seventy-one participants (mean age = 32.2 years [SE = 0.3]; 73% female) from the Oral Infections, Glucose Intolerance and Insulin Resistance Study were enrolled. Full-mouth clinical attachment loss (fm-CAL), probing depth (fm-PD) and bleeding on probing were ascertained. Interproximal CAL (i-CAL) and probing depths (i-PD) served as our primary exposures. Glucose, HbA1c, insulin and insulin resistance (HOMA-IR) outcomes were assessed from fasting blood. Prediabetes was defined per American Diabetes Association guidelines. Prediabetes prevalence ratios (PR [95% CI]) and mean [SE] cardiometabolic biomarkers were regressed on periodontal variables via multivariable robust variance Poisson regression or multivariable linear regression. RESULTS: Prevalence of prediabetes was 12.5%. Fully adjusted prediabetes PR in Tertiles 3 versus 1 of mean i-CAL was 2.42 (1.77, 3.08). Fully adjusted fasting glucose estimates across i-CAL tertiles were 83.29 [0.43], 84.31 [0.37], 86.48 [0.46]; p for trend <.01. Greater percent of sites with i-PD ≥3 mm showed elevated natural-log-HOMA-IR after adjustment (0%-12% of sites = 0.33 [0.03], 13%-26% of sites = 0.39 [0.03], ≥27% of sites = 0.42 [0.03]; p for trend = .04). CONCLUSIONS: i-CAL (vs. fm-CAL) was associated with elevated fasting glucose and prediabetes, whereas i-PD (vs. fm-PD) was associated with insulin resistance. Future studies are needed to examine periodontal disease and incident prediabetes.

Dietary nitrate intake and net nitrite-generating capacity of the oral microbiome interact to enhance cardiometabolic health: Results from the Oral Infections Glucose Intolerance and Insulin Resistance Study (ORIGINS).

Background: We investigated the association between dietary nitrate intake and early clinical cardiometabolic risk biomarkers, and explored whether the oral microbiome modifies the association between dietary nitrate intake and cardiometabolic biomarkers. Methods: Cross-sectional data from 668 (mean [SD] age 31 [9] years, 73% women) participants was analyzed. Dietary nitrate intakes and alternative healthy eating index (AHEI) scores were calculated from food frequency questionnaire responses and a validated US food database. Subgingival 16S rRNA microbial genes (Illumina, MiSeq) were sequenced, and PICRUSt2 estimated metagenomic content. The Microbiome Induced Nitric oxide Enrichment Score (MINES) was calculated as a microbial gene abundance ratio representing enhanced net capacity for NO generation. Cardiometabolic risk biomarkers included systolic and diastolic blood pressure, HbA1c, glucose, insulin, and insulin resistance (HOMA-IR), and were regressed on nitrate intake tertiles in adjusted multivariable linear models. Results: Mean nitrate intake was 190[171] mg/day. Higher nitrate intake was associated with lower insulin, and HOMA-IR but particularly among participants with low abundance of oral nitrite enriching bacteria. For example, among participants with a low MINES, mean insulin[95%CI] levels in high vs. low dietary nitrate consumers were 5.8[5.3,6.5] vs. 6.8[6.2,7.5] (p=0.004) while respective insulin levels were 6.0[5.4,6.6] vs. 5.9[5.3,6.5] (p=0.76) among partcipants with high MINES (interaction p=0.02). Conclusion: Higher dietary nitrate intake was only associated with lower insulin and insulin resistance among individuals with reduced capacity for oral microbe-induced nitrite enrichment. These findings have implications for future precision medicine-oriented approaches that might consider assessing the oral microbiome prior to enrollment into dietary interventions or making dietary recommendations.