title: Motor response to levodopa and the evolution of motor fluctuations in the first decade of treatment of Parkinson's disease.
abstract: Thirty-four patients with Parkinson's disease were followed for a mean period of 8 years from the time of initiation of levodopa medication. Levodopa response was charted from the starting point of pharmacological treatment to give a longitudinal point of view of the changes that evolve as the disease progresses. Objective measurements of the motor response to levodopa test-doses were made at approximately three yearly intervals. Motor fluctuations developed in 58% of the patient group after a mean treatment period of 35 months. Dyskinesia developed in parallel with fluctuations but appeared on average 7 months before symptomatic wearing-off effects of levodopa doses. The patients with motor fluctuations had significantly better responses to levodopa. By contrast, nonfluctuators were more prone to develop increasing midline motor disability affecting speech, gait and balance. Comparison of test-dose and pretreatment scores suggested that a substantial long-duration response to levodopa remains after many years of treatment, and that lateralized motor deficits show a stronger long duration response than midline ones. Motor fluctuations are a consequence of disease progression but their early development is, on balance, associated with better long-term functional ability because these patients have the greater capacity to respond to pharmacological treatment.
authors.affiliation: Neurosciences Department, Monash Medical Centre, Melbourne, Australia.
authors.forename: Craig D
authors.initials: CD
authors.lastname: McColl
authors.forename: Katrina A
authors.initials: KA
authors.lastname: Reardon
authors.forename: Mark
authors.initials: M
authors.lastname: Shiff
authors.forename: Peter A
authors.initials: PA
authors.lastname: Kempster
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000978:Antiparkinson Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004409:Dyskinesia, Drug-Induced / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality / Q000187:drug effects; D006801:Humans; D007980:Levodopa / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000187:drug effects*; D009460:Neurologic Examination / Q000187:drug effects*; D010300:Parkinson Disease / Q000175:diagnosis / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa