Peripheral diabetic neuropathy: current concepts in treatment.

OBJECTIVE

To review pathophysiology and current concepts in the treatment of diabetic peripheral neuropathy (PN).

DATA SOURCES

References were identified through a MEDLINE search of the English-language literature from 1976 through 1994. Additional references were obtained from reference lists of articles identified through the search.

STUDY SELECTION AND DATA EXTRACTION

All articles were considered for possible inclusion in the review. Clinical trials that involved an adequate number of patients and review articles were selected. Information from articles that was judged by the authors to be significant was selected for discussion.

DATA SYNTHESIS

PN affects 5-50% of people with diabetes in the US and most commonly is characterized by tingling or burning sensations, particularly in the calves, ankles, and feet, with a loss of vibratory sense. Treatment of PN, for the most part, has been unsatisfactory. Therapy has been directed toward either improving nerve function or alleviating symptoms of PN, including pain and paresthesia. Glycemic control may slow the progression of PN. Hyperglycemia also is associated with decreased pain threshold in patients with diabetes mellitus. The aldose reductase inhibitors, particularly tolrestat, have been shown to improve objective and subjective neurologic function. Pain or paresthesia has been treated effectively with antidepressants, lidocaine, mexiletine, and capsaicin. The anticonvulsants phenytoin and carbamazepine may be effective, but are associated with a greater degree of adverse effects. Experimental treatments, such as gamma-linolenic acid, gangliosides, uridine, and the corticotropin4-9 analog ORG 2766, have been effective in improving neurologic function.

CONCLUSIONS

Treatment of PN remains unsatisfactory. Therapy should be directed toward prevention with glycemic control and symptomatic treatment of existing PN.