Alpha lipoic acid supports healthy nerve function, review shows

Summary

This review was designed to critically assess the available evidence for the effectiveness and tolerability of alpha lipoic acid (ALA) in the treatment of symptomatic diabetic polyneuropathy.

Eligible for inclusion in this review were randomized clinical studies published in the literature on or before April 11, 2011 comparing the use of oral or parenteral ALA with placebo for treatment of painful peripheral neuropathy in adults with type 1 and type 2 diabetes. Meta-analyses adhering to the standards of the Cochrane Collaboration and systematic reviews were also considered. Studies evaluating the effect of ALA on autonomic neuropathy and diabetic mononeuropathy were excluded.

Five randomized, double-blind placebo-controlled trials – ALADIN, SYDNEY, ORPIL, SYDEY 2, and ALADIN III studies – comprising a total of 1,160 people met the inclusion criteria and were included in this review. The study populations included subjects ranging in age from 18 to 74 years with type 1 and type 2 diabetes. Mean body mass indices ranged from 28 to 31. Initial glycosylated hemoglobin was less than 12%, on average. The duration of diabetes ranged from 10 to 15 years with polyneuropathy for 3 to 5 years, on average. The studies took place in inpatient and outpatient treatment centers throughout Germany, Russia, and Israel.

Most of the studies (4/5; 80%) reported significant improvements in polyneuropathy. Results indicate that parenteral treatment with ALA (600 mg/day, intravenously for 3 weeks) represents a well-tolerated and effective therapy for diabetic polyneuropathy. Similarly, oral supplementation (600 mg/day for up to 5 weeks) offered symptomatic relief.

These findings suggest that ALA supplementation has clinical value for the relief of signs and symptoms of polyneuropathy associated with diabetes.