Objective: To evaluate the effect of alpha-lipoic acid (ALA) on diabetic peripheral neuropathy (DPN).
Methods: 95 type 2 diabetic patients complicated with DPN were randomly divided into 2 groups: treatment group (n = 52), receiving ALA 600 mg/d in normal saline 250 ml given by intravenous drip infusion once a day for 14 days; and control group (n = 43), administered with radix salviae 20 ml by intravenous drip infusion once a day for 14 days. Before and 7 and 14 days after the management fasting glucose (FPG), fasting insulin (FINS), supersensitive C reactive protein (sCRP), and HbA1c were measured, and total symptom score (TSS) and Michigan neuropathy screening instrument (MNSI) were used to evaluate the nervous symptoms.
Results: 50 cases of the treatment group and 43 control cases completed the study. Compared with the control group, the TSS of the treatment group reduced significantly after 1 week, but the MNSI score did not change significantly. The TSS 7d after ALA administration of the treatment group was significantly lower than that before the ALA treatment in the same group and that of the control group 7 days after the radix salviae infusion as well (both P < 0.05). The TSS and MNSI score 14 days after the management of the treatment group were significantly lower than those of the control group (both P < 0.01). The symptom scores of numbness, sting sensation, and burning sensation reduced significantly 2-weeks after ALA treatment, but there were no significant differences in these symptoms after the management in the control group. The total gratification rate of the treatment group was 90% (45/50), significantly higher than hat of the control group (13.95%, 6/43, P < 0.01). One patient of the 50 patients receiving ALA treatment felt chest distress 2 days after ALA administration, but the symptom was improved in the same day after the velocity of intravenous drip was slowed down, and no other adverse effects were found in these two groups.
Conclusion: ALA effectively improves the sensitive symptoms of DPN patients and is safe for most of the patients.