Vitamin B12 Supplementation in Diabetic Neuropathy: A 1-Year, Randomized, Double-Blind, Placebo-Controlled Trial

Aim: To investigate the effect of normalizing vitamin B12 (B12) levels with oral (methylcobalamin) 1000 ?g/day for one year in patients diabetic neuropathy (DN). Patients and methods: In this prospective, double-blind, placebo-controlled trial, 90 type 2 diabetes on metformin at least four years both peripheral autonomic DN were randomized to an active treatment group (n = 44) receiving a control 46) placebo. All had less than 400 pmol/L. Subjects underwent measurements sural nerve conduction velocity (SNCV), action potential (amplitude) (SNAP), vibration perception threshold (VPT), they performed cardiovascular reflex tests (CARTs: mean circular resultant (MCR), Valsalva test, postural index, orthostatic hypotension). Sudomotor function was assessed SUDOSCAN that measures electrochemical skin conductance hands feet (ESCH ESCF, respectively). We also used Michigan Neuropathy Screening Instrument Questionnaire Examination (MNSIQ MNSIE, respectively) questionnaires evaluate quality life (QoL) level pain (pain score). Results: increased from 232.0 ± 71.8 baseline 776.7 242.3 pmol/L follow-up, p < 0.0001, but not group. VPT, MNSIQ, QoL, score, SNCV, SNAP, ESCF significantly improved (p 0.001, 0.002, 0.000, 0.014, respectively), whereas CARTS MNSIE significantly. MCR, score deteriorated 0.025, 0.017, 0.045, Conclusions: The 1 mg methylcobalamin twelve months plasma all neurophysiological parameters, sudomotor function, it did improve MNSIE.