Chronic periodontitis and the risk of diabetic peripheral neuropathy in type 2 diabetes: a retrospective cohort study.

BACKGROUND

Chronic periodontitis is a common inflammatory condition that may contribute to systemic inflammation and microvascular complications in type 2 diabetes mellitus (T2DM). However, longitudinal evidence linking periodontitis to diabetic peripheral neuropathy (DPN) remains scarce.

OBJECTIVE

To investigate whether chronic periodontitis is associated with an increased risk of incident DPN in patients with T2DM.

METHODS

We conducted a single-center retrospective cohort study using electronic medical records from 2017 to 2022. A total of 3,996 T2DM patients without baseline DPN were included, of whom 318 had incident chronic periodontitis. Propensity score matching (1:1) was applied to balance baseline characteristics, resulting in 604 patients (302 with periodontitis, 302 without). The primary outcome was incident DPN, identified using ICD-10 codes and confirmed by neurologist/endocrinologist diagnosis or abnormal nerve conduction studies. Cox proportional hazards models were used to estimate hazard ratios (HRs) adjusted for age, sex, diabetes duration, HbA1c, health insurance type, and metformin use.

RESULTS

Over a median follow-up of 3.8 years, the incidence of DPN was significantly higher in the periodontitis group (42.7% vs. 27.5%, P < 0.001). The adjusted HR for DPN associated with chronic periodontitis was 1.63 (95% CI: 1.22-2.18, P < 0.001). Subgroup analyses confirmed consistent associations across age, sex, and glycemic control strata. Sensitivity analyses, including alternative matching, lag-time analysis, and exclusion of metformin users, supported the robustness of the findings.

CONCLUSION

Chronic periodontitis is an independent risk factor for the development of DPN in patients with T2DM. These findings highlight the importance of integrated oral health management in diabetes care to potentially mitigate neuropathic complications.