Electroencephalographic findings in patients with mild Parkinson's disease treated with L-dopa and placebo

The prognostic value of electroencephalograms in patients with early or mild Parkinson's disease treated with L-dopa is discussed. Fifteen patients with early or mild Parkinson's disease were studied clinically and electroencephalographically while receiving L-dopa or placebo treatment. Only a low incidence (four patients, 27%) of EEG abnormality was found. These patients showed only mild improvement: in three cases, the improvement followed an initial worsening in the first three months. Only one (13%) of the patients with a normal EEG became worse or failed to improve. The potential use of EED data in parkinsonism is discussed.