Aida Fitri¹, Hasan Sjahrir¹, Adang Bachtiar², M. Ichwan³
¹Department of Neurology Faculty of Medicine Universitas Sumatera Utara, Indonesia²Faculty of Public Health Universitas Indonesia
³Department of Pharmacology and Therapeutic Faculty of Medicine Universitas Sumatera Utara, Indonesia
Background: Diabetic neuropathy (DN) is one of the most common complication in patients with type 2 diabetes mellitus
(T2DM). Diabetic neuropathy is the most common form of neuropathy in developed countries. Low levels of circulating
vitamin D may contribute to large fiber neuropathy in diabetic patients. In some literatures, there are conflicting reports on
the effect of vitamin D on nerve conduction studies (NCSs).
Objective: To investigate the effect of vitamin D supplementation on NCSs in T2DM Indonesian patients.
Methods: Fifty subjects with T2DM in Haji Adam Malik General Hospital Medan, were randomly divided into 2 groups.
The groups were treated for 10 weeks either with placebo or vitamin D (D3) supplementation of 50.000 IU/week, double-
blind trial. They were evaluated by routine NCSs in upper and lower limbs, before and 10 weeks after placebo or vitamin
D supplementation. The effect of vitamin D supplementation on NCSs was analyzed using linear regression.
Results: Vitamin D supplementation had significant decrease in distal latencies (DLs) of motor median, peroneal, and tibial
nerve, motor and sensory ulnar nerve (p <0.001), increase in amplitudes (As) of motor and sensory median and ulnar nerve,
motor peroneal and tibial nerve, and sensory sural nerve (p <0.001), and increase in nerve conduction velocities (NCVs)
of motor median and peroneal nerve, motor and sensory ulnar nerve (p <0.001). There were neither significant effect of
vitamin D supplementation in DL and NCVs of sensory median and sural nerve, nor NCVs of motor tibial nerve.
Conclusion: Vitamin D supplementation for 10 weeks had effect on NCSs in T2DM Indonesian patients.
