title: Do patients with late-stage Parkinson's disease still respond to levodopa?
abstract: Late-stage Parkinson' disease (PD) is dominated by loss of autonomy due to motor and non-motor symptoms which can be marginally corrected by medications adjustments. However, controversy exists on the mechanisms underlying the apparent decrease of benefit from levodopa.
  
  
  
  To study the response to levodopa in late-stage PD (LSPD).
  
  
  
  20 LSPD patients (Schwab and England ADL Scale <50 or Hoehn Yahr Stage >3 in MED ON) and 22 PD patients treated with subthalamic deep brain stimulation (DBS) underwent an acute levodopa challenge test. MDS-UPDRS-III and the modified Abnormal Involuntary Movement Scale were evaluated in off and after administration of a supra-maximal levodopa dose.
  
  
  
  LSPD patients had a median age of 78.8 (IQR: 73.5-82) and median disease duration of 14 years (IQR: 10-19.75). DBS patients had a median age of 66 (IQR: 61-72) and median disease duration of 18 years (IQR: 15-22). LSPD and DBS patients' MDS-UPDRS-III score improved 11.3% and 37% after levodopa, respectively. Rest tremor showed the largest improvement, while axial signs did not improve in LSPD. However, the magnitude of levodopa response significantly correlated with dyskinesias severity in LSPD patients. One third of LSPD and 9% of DBS patients reported moderate drowsiness.
  
  
  
  LSPD patients show a slight response to a supra-maximal levodopa dose, which is greater if dyskinesia are present, but it is frequently associated with adverse effects. A decrease in levodopa response is a potential marker of disease progression in LSPD.
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal.
authors.forename: Margherita
authors.initials: M
authors.lastname: Fabbri
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal; Neurology Service, Department of Neurosciences, Hospital Santa Maria, Lisbon, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Coelho
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal.
authors.forename: Daisy
authors.initials: D
authors.lastname: Abreu
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal; Neurology Service, Department of Neurosciences, Hospital Santa Maria, Lisbon, Portugal.
authors.forename: Leonor Correia
authors.initials: LC
authors.lastname: Guedes
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal; Neurology Service, Department of Neurosciences, Hospital Santa Maria, Lisbon, Portugal; Laboratory of Clinical Pharmacology and Therapeutics, Faculty of Medicine, University of Lisbon, Portugal.
authors.forename: Mario M
authors.initials: MM
authors.lastname: Rosa
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal.
authors.forename: Nilza
authors.initials: N
authors.lastname: Costa
authors.affiliation: Parkinson and Movement Disorders Unit, IRCCS Hospital San Camillo, Venice, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Antonini
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal; Neurology Service, Department of Neurosciences, Hospital Santa Maria, Lisbon, Portugal; Laboratory of Clinical Pharmacology and Therapeutics, Faculty of Medicine, University of Lisbon, Portugal. Electronic address: joaquimjferreira@gmail.com.
authors.forename: Joaquim J
authors.initials: JJ
authors.lastname: Ferreira
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa
keywords: Advanced stage; Late stage; Levodopa test; Parkinson's disease