Response to L-dopa and evolution of motor fluctuations in the early phase of treatment of Parkinson's disease.

Twenty patients with Parkinson's disease were studied during the early phase of L-dopa treatment to clarify the development and progression of Parkinsonian motor fluctuations. Two patients had developed symptomatic motor fluctuations of moderate severity and another 3 had mild fluctuations. Both the initial response to L-dopa and the amplitude of response to a L-dopa test dose after a mean follow up period of 30 months were significantly greater for the fluctuating patients compared with those without fluctuation (p < 0.05). Although severe motor fluctuations do not usually develop until a number of years of L-dopa treatment have elapsed, this study shows that motor fluctuations can be detected quite early in the disease course and tend to appear in those patients who respond best to L-dopa.