title: Abnormal Olfaction in Parkinson's Disease Is Related to Faster Disease Progression.
abstract: BACKGROUND
  A possible association between olfactory dysfunction and Parkinson's disease (PD) severity has been a topic of contention for the past 40 years. Conflicting reports may be partially explained by procedural differences in olfactory assessment and motor symptom evaluation.
  
  
  METHODS
  One hundred and sixty-six nondemented PD patients performed the Brief-Smell Identification Test and test scores below the estimated 20th percentile as a function of sex, age, and education (i.e., 80% specificity) were considered demographically abnormal. Patients underwent motor examination after 12 h without antiparkinsonian medication.
  
  
  RESULTS
  Eighty-two percent of PD patients had abnormal olfaction. Abnormal performance on the Brief-Smell Identification Test was associated with higher disease severity (i.e., Hoehn and Yahr, Unified Parkinson's Disease Rating Scale-III, Freezing of Gait questionnaire, and levodopa equivalent dose), even when disease duration was taken into account.
  
  
  CONCLUSIONS
  Abnormal olfaction in PD is associated with increased severity and faster disease progression.
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal ; Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal.
authors.forename: Sara
authors.initials: S
authors.lastname: Cavaco
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal ; Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal ; Faculdade de Medicina, Universidade do Porto, 4200 Porto, Portugal.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Gonçalves
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal ; Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Mendes
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal ; Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal ; Faculdade de Medicina, Universidade do Porto, 4200 Porto, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Vila-Chã
authors.affiliation: Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal.
authors.forename: Inês
authors.initials: I
authors.lastname: Moreira
authors.affiliation: Unidade Multidisciplinar de Investigação Biomédica, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050 Porto, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Fernandes
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Damásio
authors.affiliation: CINTESIS, Faculdade de Medicina, Universidade do Porto, 4200 Porto, Portugal ; Screening and Test Evaluation Program, Sydney School of Public Health, The University of Sydney, NSW 2006, Australia.
authors.forename: Armando
authors.initials: A
authors.lastname: Teixeira-Pinto
authors.affiliation: Serviço de Neurologia, Centro Hospitalar do Porto, 4099 Porto, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Bastos Lima
mesh_terms: D000368:Aged; 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 / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology*; D012903:Smell; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa