Auditory evoked potentials (AEPs), early (BAEPs) and long latency components (LLCs) in Parkinson's disease: a 12 month follow-up study.

In 14 untreated informed patients (5 M, 9 F, mean age 62 yrs) with initial idiopathic Parkinson's disease AEPs, early (BAEPs) and long latency components (LLCs) were studied. In 10 subjects experimental session were carried out before treatment (L-Dopa plus Carbidopa, 0.25-0.50 g/die) and at 2, 6 and 12 months intervals. At the same time all patients underwent clinical assessment by Webster Rating Scale evaluation. BAEPs. The IPLs prolonged (greater than 2.5 SD) in 6 patients: in 3 the III-V, in 2 the I-V and in 1 the I-III. The absolute latencies were abnormally prolonged in 11 subjects: V wave in 4, III wave in 3, II wave in 2 and I wave in 3. The absence of one or more components were observed in 12 out of 14 patients, the most frequently absent was the II wave (12 patients). LLCs. The absolute latencies of P1 and N1 waves were prolonged respectively in 4 and in 3 subjects. The P1-N1 IPL was prolonged only in one patient. A follow-up study demonstrated transitory improvement of the AEPs previously observed abnormalities. The improvement was partially in agreement with clinical assessment.