Association between serum α-Klotho levels and severity of periodontitis in a representative U.S. population.

<h4>Background</h4>Periodontitis, a chronic inflammatory disease, is linked to systemic conditions such as cardiovascular and kidney disease. Serum α-Klotho, an anti-aging protein with anti-inflammatory properties, has been associated with systemic diseases, but its role in periodontitis is unclear. This study evaluated the relationship between serum α-Klotho levels and periodontitis severity while accounting for confounders.<h4>Methods</h4>In this cross-sectional study, data from 961 participants in the National Health and Nutrition Examination Survey (NHANES) database were analyzed. Periodontitis was classified into stages (I-IV) and grades (A-C) using the ACES (Application of the 2018 periodontal status Classification to Epidemiological Survey data) guidelines. Serum α-Klotho levels were measured via enzyme-linked immunosorbent assay (ELISA). Ordinal logistic regression assessed associations between α-Klotho levels and periodontitis, adjusting for confounders such as age, smoking, comorbidities, and oral hygiene. The number of lost teeth was analyzed as a secondary outcome.<h4>Results</h4>In both adjusted and unadjusted regression models, no significant association was found between α-Klotho levels and periodontitis. Particularly, adjusted models revealed no significant association between α-Klotho levels and periodontitis stage (OR = 1.0001, p = 0.547, 95% CI: 0.9997-1.0006) or grade (OR = 0.9996, p = 0.144, 95% CI: 0.9991-1.0001). Age, smoking, and comorbidities significantly predicted severity. Despite a weak negative correlation between α-Klotho and tooth loss (r = -0.07, p = 0.023), this association was no longer significant after adjustment.<h4>Conclusion</h4>No significant association was found between serum α-Klotho levels and periodontitis severity. Age, smoking, and comorbidities were key predictors, highlighting the multifactorial nature of periodontitis. Further longitudinal and mechanistic studies are needed to clarify whether α-Klotho has a value as a biomarker of periodontal inflammation or disease progression.