Central nervous system involvement in elderly patients with non-insulin-dependent diabetes mellitus.

We examined cognitive functions and central conduction velocities in 20 patients, over 63-year old, with NIDDM compared with 20 normal, age-matched controls. Mean conduction velocity of median nerve, was significantly lower in diabetics than in controls, but absolute values were within normal range. Neurological examination showed clinical signs of lower limbs neuroperipheral involvement. Only one cognitive subtest performance was abnormal whereas there was no impairment in central conduction velocities. In our study population, although median nerve conduction velocity values may introduce a bias of low peripheral neuropathy incidence, there was no evidence of a massive or progressive specific central nervous system involvement caused by NIDDM.