Cross-sectional Association Between Insulin Resistance and Clinical Periodontal Measures

Methods: We analyzed data from 1,204 overweight and obese participants aged 40 to 65 and free of major cardiovascular disease and diabetes recruited at the baseline visit of the ongoing San Juan Overweight Adults Longitudinal Study (SOALS). Participants underwent anthropometric measurements, periodontal examination, face-to-face interview, and blood drawing. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Percentage of teeth with bleeding on probing (BOP) and three types of case definitions of periodontal disease were evaluated: (1) having at least 1 site with probing depth (PD) ≥ 5, (2) at least 1 site with clinical attachment loss (CAL) ≥ 5 mm and (3) at least 1 site with both BOP and PD ≥ 5 mm in the same tooth. Multivariate logistic regression analyses were performed while controlling for age, gender, education, smoking, alcohol consumption, waist circumference, plaque index and number of teeth.

Results: The percentage of participants with BOP, PD≥5 mm, CAL≥5 mm, and combined case definition of periodontal disease were 28%, 45%, 60%, and 36%, respectively. In logistic regression models, HOMA (upper vs. lower quartiles) was associated with percentage of BOP (above vs. below the median, OR=1.43, 95% CI: 1.05-1.96), with having at least 1 site with PD ≥ 5 (OR=1.40, 95% CI: 1.03-1.92), with having at least 1 site with CAL ≥ 5 (OR=1.44, 95% CI: 1.03-2.02), and with the combined definition of periodontal disease (OR=1.45, 95% CI: 1.05-1.99).

Conclusions: Findings from this study show consistency of the association between insulin resistance, a precursor of type 2 diabetes, and different periodontal measures. Future longitudinal studies are needed to determine the directionality of these inter-relationships.