Vitamin D Deficiency as a Factor Associated with Neuropathic Pain in Multibacillary Type Morbus Hansen

Objective: Morbus Hansen (MH), caused by Mycobacterium leprae, is marked by neuropathic pain. Prior studies link low vitamin D levels to diabetic neuropathic pain, yet research on its role in MH-related neuropathic pain is limited. This study investigates the role of vitamin D deficiency in MH-related neuropathic pain. Materials and Methods: An analytical cross-sectional study was conducted among multibacillary (MB) MH patients at Prof. Dr. I.G.N.G. Ngoerah Hospital, Bali from April to August 2023. Neuropathic pain was assessed using the Douleur Neuropathique 4 (DN4) questionnaire, while serum 25(OH)D levels determined vitamin D status. The cutoff for deficiency was determined via ROC curve analysis. Results: Among 42 participants, those without neuropathic pain exhibited higher mean serum vitamin D levels than those with neuropathic pain (28.69 ± 8.16 vs. 22.11 ± 9.54 ng/ml; p=0.021). The ROC curve identified a cutoff value of 30.25 ng/ml, categorizing participants into vitamin D deficiency (<30.25 ng/ml) and non-deficiency (≥30.25 ng/ml) groups. Bivariate analysis revealed a heightened incidence of neuropathic pain among MH patients with serum vitamin D levels below the designated cutoff point (OR: 6.60; 95%CI: 1.484-29.355; p=0.022). Multivariate analysis indicated that two variables significantly correlated with neuropathic pain in MH patients: vitamin D deficiency (OR: 14.337; 95%CI: 2.431-84.542; p=0.003) and peripheral nerve enlargement (OR: 12.564; 95%CI: 2.096-75.307; p=0.006). Conclusion: Disparities in average vitamin D levels were observed between MH patients with and without neuropathic pain. Vitamin D deficiency, alongside peripheral nerve enlargement, emerged as significant risk factors for neuropathic pain in MH patients.