Elevated glycosylated hemoglobin in diabetic neuropathy.

Glycosylated hemoglobin (GHb) levels were measured in 36 patients with established symptomatic neuropathy and in an identical number of matched controls. Strict criteria were employed in the selection of subjects and all had neuropathy of at least 12 months' duration. The diagnosis of neuropathy was supported by estimation of motor conduction velocities and vibration perception threshold. A semi-automated colorimetric technique, employing the reaction between thiobarbituric acid and 5-hydroxy-methyl furfural, was used for the estimation of GHb. Those patients with neuropathy had significantly higher GHb levels (58.2 +/- 11.3 mmol HMF/mol Hb) than the controls (50.0 +/- 8.9 mmol HMF/mol Hb) (p less than 0.01). This suggests that hyperglycemia or related metabolic abnormalities are important factors in established symptomatic neuropathy.