title: Short-term levodopa test assessed by movement time accurately predicts dopaminergic responsiveness in Parkinson's disease.
abstract: Short-term challenges with dopaminergic agents are used in patients with idiopathic Parkinson's disease (PD) to predict the therapeutic effect of sustained levodopa treatment, but false-negative results often occur. We prospectively evaluated 74 patients with clinically diagnosed IPD and compared the predictive value of a short-term levodopa test assessed by movement time (MT) with the predictive value obtained by the evaluation with the motor examination part of the Unified Parkinson's Disease Rating Scale (UPDRS-ME). The response to long-term levodopa was accurately predicted in 96% of patients by assessing the response to the short-term test with MT and in 80% of cases with UPDRS-ME. Similar predictive values were obtained by separately analyzing 21 de novo patients. The short-term test also accurately predicted the magnitude of improvement with long-term treatment. We conclude that the predictive value for long-term dopaminergic responsiveness may be further enhanced by evaluating the short-term pharmacologic challenges with MT analysis. This is particularly useful to select de novo patients for drug trials with dopaminergic agents.
authors.affiliation: Institute of Neurology, School of Medicine in Catanzaro, University of Reggio Calabria, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Zappia
authors.forename: R
authors.initials: R
authors.lastname: Montesanti
authors.forename: R
authors.initials: R
authors.lastname: Colao
authors.forename: D
authors.initials: D
authors.lastname: Branca
authors.forename: G
authors.initials: G
authors.lastname: Nicoletti
authors.forename: U
authors.initials: U
authors.lastname: Aguglia
authors.forename: A
authors.initials: A
authors.lastname: Quattrone
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000008:administration & dosage; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination / Q000187:drug effects; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D011379:Prognosis; D011597:Psychomotor Performance / Q000187:drug effects* / Q000502:physiology; D011930:Reaction Time / Q000187:drug effects* / Q000502:physiology; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000502:physiology
chemical_list: D000978:Antiparkinson Agents; D011954:Receptors, Dopamine; D007980:Levodopa