Clinical and electrophysiological signs of diabetic polyneuropathy -- effect of glycemia and duration of diabetes mellitus.

Diabetic polyneuropathy occurs in around 50% of diabetic patients. Its pathophysiological mechanism is not completely clarified and major occurrences boil down to the change in neural phenotype and vasa nervorum. As glucose neurotoxicity has been suggested by plenty of evidence, the aim of the study was to assess the effect of glycemia on the severity of diabetic polyneuropathy. Considering that some practical experiences point to serious complications in patients suffering from diabetes of shorter duration, another aim was to assess the effect of diabetes duration on the severity of related neuropathy. Clinical and electromyoneurographic examinations were performed in 100 patients with diabetic polyneuropathy free from any laboratory signs of renal failure. The effect of HbA1c value and duration of disease on clinical symptoms, signs and electrophysiological indicators of polyneuropathy was analyzed. Study results indicated that 78% of patients with diabetic polyneuropathy did not have well-regulated glycemia. Diabetes duration was associated with a growing number of sensory symptoms, among which the sensation of pain similar to electric shock was present in 63% of patients. In addition, it also had negative impact on the sensory and motor nerve conduction velocity. HbA1c influenced the whole range of electrophysiological indicators of diabetic polyneuropathy.