VISUAL-EVOKED POTENTIALS IN NIDDM - A LONGITUDINAL-STUDY

In order to assess the possible progression of neurological abnormalit ies over time and the value of visual evoked potential alterations in predicting stability and severity of diabetes-related optic pathway di sease, a longitudinal study in non-insulin-dependent diabetic patients was performed. Neurological examination, visual evoked potentials wit h pattern reversal, motor and sensory nerve conduction velocities and metabolic control were studied in 18 non-insulin-dependent diabetic pa tients and in 35 normal control subjects at baseline and again after 4 .6 +/- 0.8 years (range 4-6). At the first recording the peak P100 wav e latencies were significantly delayed in the diabetic patients compar ed with the control subjects; signs of peripheral neuropathy were dete cted in five patients, clinical in three and in two there was only neu rophysiological alteration without clinical signs. The second recordin g revealed no significant alterations of P100 latencies in patients co mpared with baseline, but the number with clinical signs and/or neurop hysiological alterations with no clinical signs of peripheral neurolog ical disease was increased to seven. In conclusion, we observed that v isual evoked potential alterations were stable over time whereas perip heral neurological disease progressed and correlated positively with m etabolic control.