Painful sensory polyneuropathy associated with impaired glucose tolerance

We examined records of 121 patients coded as idiopathic polyneuropathy, ext racting neuropathy symptoms, electromyographic data, and diagnostic blood w ork. Of 89 patients screened for glucose handling, 28 demonstrated frank di abetes mellitus. Of the remaining 61 patients, 15 (25%) had impaired glucos e tolerance (IGT) by American Diabetes Association criteria (serum glucose 140-200 mg/dl 2 h after a 75-g glucose load). Excluding those with diabetes mellitus, 35% of patients with neuropathic pain had IGT, more than twice t he prevalence found in large, unselected population studies. No other commo n etiology of polyneuropathy was identified. Two-hour oral glucose toleranc e test results were often abnormal, whereas fasting glucose or hemoglobin A 1c was normal. Bias due to referral pattern, body weight, or genetics might affect the comparison of our polyneuropathy cohort with a broader, populat ion-based control. However, our results corroborate an association between IGT and painful sensory polyneuropathy and link these patients syndromicall y to the typical painful polyneuropathy of diabetes mellitus. (C) 2001 John Wiley & Sons, Inc.