Tobacco Habit Duration And Its Association With Oral Mucosal Lesions And Salivary Alpha-Klotho Levels: A Cross-Sectional Study

Background Tobacco use is a significant risk factor for oral mucosal lesions (OMLs) and oxidative stress-induced damage to oral tissues. Alpha-Klotho, a cytoprotective and antiaging protein, has surfaced as a prospective noninvasive salivary biomarker; nevertheless, its significance in populations exposed to tobacco has yet to be inadequately investigated. This research evaluated salivary alpha-Klotho levels in connection with demographic factors, tobacco use patterns, length of habits, and oral mucosal lesions among people in the Kanchipuram area. Methods Cross-sectional analytical research involving 200 adult tobacco users (smokers n = 75, smokeless n = 70, mixed n = 55) recruited from dentistry clinics and community screening initiatives was performed. Demographic data, tobacco use patterns, and OML status were documented via a standardized questionnaire and WHO oral examination standards. Unstimulated saliva samples were analysed for alpha-Klotho expression via ELISA. Statistical studies included t-tests, ANOVA, Pearson correlation, and multiple regression (SPSS v26.0; p < 0.05). Results The average salivary alpha-Klotho concentration was 472.1 ± 102.8 pg/mL. Alpha-Klotho exhibited a notable age-associated reduction (r = − 0.256, p = 0.009) and diminished gradually with increasing length of habit (< 5 years: 532.8 ± 94.2; 5–10 years: 474.9 ± 89.4; >10 years: 412.6 ± 83.7 pg/mL; p = 0.002). Significant variations in habit types were observed (p = 0.018), with smokers exhibiting the highest levels (512.4 ± 107.6), followed by smokeless users (469.1 ± 93.8) and mixed users (422.8 ± 84.5 pg/mL). Compared with OML-free individuals,participants with OMLs had significantly lower alpha-Klotho concentrations (428.3 ± 88.9 pg/mL) (506.7 ± 101.5 pg/mL; p = 0.006). Multiple regression accounted for 39% of the variation (R² = 0.39, p < 0.001), with length of usage (β = −0.304), OML presence (β = −0.264), habit type (β = −0.207), and age (β = −0.182) identified as significant negative predictors. Conclusion Salivary alpha-Klotho concentrations decrease with increasing age, prolonged tobacco exposure, mixed use patterns, and the presence of OMLs. These results underscore alpha-Klotho as a potential noninvasive biomarker for oxidative stress and the early identification of oral disease in high-risk tobacco-using groups.