Vitamin B6 status, type 2 diabetes mellitus, and periodontitis: evidence from the NHANES database 2009-2010

Periodontitis is a chronic inflammatory disease that seriously affects the quality of patients' life. Diabetes mellitus (DM) is the independent risk factor of periodontitis. The association between vitamin B₆ with several inflammatory diseases have been reported in previous studies. However, the effect of vitamin B₆ on the association of T2DM and periodontitis remains unclear. This study aimed to explore the effect of vitamin B₆ [evaluated by serum pyridoxal 5'-phosphate (PLP)] on the association of T2DM and periodontitis in American population.

Data of this cross-sectional study were extracted from the National Health and Nutrients Examination Survey (NHANES) 2009-2010. Serum PLP level was the indicator of vitamin B₆ status in vivo and measured by enzymatic assay. Covariates included demographic information, physical examination, lifestyle characteristics, laboratory parameters and complications. The weighted univariate and multivariate logistics regression models were conducted to explore the association of PLP, T2DM and periodontitis, with the odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were further performed to explore these associations based on age, body mass index (BMI), cardiovascular disease (CVD) and dental decay.

Finally, 3,491 eligible adults with the information of periodontitis measurement, T2DM diagnosis and PLP detection were included. Among them, 1,999 (57.26%) had periodontitis. After adjusted confounders, we found adults with T2DM had high odds of periodontitis (OR = 1.45, 95%CI: 1.04-2.02); while no significant association between PLP and periodontitis was observed. Adults with low PLP level (< 67.20 nmol/L) and combined with T2DM had high odds of periodontitis (OR = 1.82, 95%CI: 1.29-2.55), no significant association was found between T2DM and periodontitis in adults with high PLP level (≥ 67.20 nmol/L). These results suggested that serum PLP levels may have the modulatory effect on the association of T2DM and periodontitis. This modulatory effect remains robust in subgroup analysis, especially in adults aged ≥ 60 years (OR = 4.54, 95%CI: 2.15-9.62), with obese (OR = 3.06, 95%CI: 1.31-7.18), without the history of CVD (OR = 2.25, 95%CI: 1.06-4.79) and without dental decay (OR = 2.93, 95%CI: 1.51-5.68) (all P < 0.05).

Our study suggested that adults with T2DM had the high odds of periodontitis, and serum PLP may plays a modulatory effect in this association. T2DM patients maintaining a higher intake of vitamin B₆ may have potential benefits in reducing the periodontitis risk.