title: Evolution of motor fluctuations in Parkinson's disease: a longitudinal study over 6 years.
abstract: A prospective longitudinal 6-year study of 34 patients with Parkinson's disease from the time of initiation of drug treatment explored changes in the motor response to L-dopa over the early to mid disease course. Motor fluctuations developed in 41% after a mean L-dopa treatment interval of 25 months and dyskinesia developed in 53% after a mean of 15 months' treatment. Patients who developed fluctuations had a significantly better response to L-dopa than nonfluctuators. Nonfluctuators also had significantly greater "midline" motor disability affecting cranial and truncal muscles and gait. The development of motor fluctuations may simply reflect a retained capacity to respond to L-dopa as endogenous dopaminergic neurotransmission declines with progressive nigral cell loss. Many patients who show no sign of motor fluctuation 5 or 6 years into the disease course have a relatively blunted response to L-dopa. The proportion of such cases seems to correspond to the percentage that have coexisting striatal pathologic changes in postmortem studies.
authors.affiliation: Department of Neurosciences, Monash Medical Centre, Clayton, Victoria, Australia.
authors.forename: K A
authors.initials: KA
authors.lastname: Reardon
authors.forename: M
authors.initials: M
authors.lastname: Shiff
authors.forename: P A
authors.initials: PA
authors.lastname: Kempster
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000978:Antiparkinson Agents / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa