Impaired sense of smell and color discrimination in monogenic and idiopathic Parkinson's disease

Research output: Contribution to journalJournal articlepeer-review

  • Lena Kertelge
  • Norbert Brüggemann
  • Alexander Schmidt
  • Vera Tadic
  • Claudia Wisse
  • Sylwia Dankert
  • Laura Drude
  • Joyce van der Vegt
  • Siebner, Hartwig Roman
  • Heike Pawlack
  • Peter P Pramstaller
  • Maria Isabel Behrens
  • Alfredo Ramirez
  • Dirk Reichel
  • Carsten Buhmann
  • Johann Hagenah
  • Christine Klein
  • Katja Lohmann
  • Meike Kasten
Olfaction is typically impaired in idiopathic Parkinson's disease (IPD), but its role is uncertain in monogenic PD. Diminished color discrimination has been suggested as another early sign of dopaminergic dysfunction but not been systematically studied. Furthermore, it is unknown whether both deficits are linked. We examined 100 patients with IPD, 27 manifesting mutation carriers (MC), 20 nonmanifesting mutation carriers (NMC), and 110 controls. Participants underwent a standardized neurological examination, the University of Pennsylvania Smell Identification Test (UPSIT), the Farnsworth-Munsell (FM) color discrimination test, and mutation testing in known PD genes. The monogenic group consisted of 15 Parkin (6MC/9NMC), 17 PINK1 (10MC/7NMC), 8 LRRK2 (4MC/4NMC), 3 SNCA (MC), and 4 ATP13A2 (MC) carriers. Olfaction was most impaired in IPD (UPSIT percentiles 10.1 ± 13.5) compared with all other groups (MC 13.8 ± 11.9, NMC 19.6 ± 13.0, controls 33.8 ± 22.4). Within MC, carriers of two mutations in Parkin and PINK1 showed higher UPSIT percentiles than LRRK2 and SNCA carriers. Color discrimination was reduced in IPD (FM total error score 134.8 ± 92.7). In MC (122.4 ± 142.4), the reduction was most pronounced in LRRK2, NMC (80.0 ± 38.8) were comparable with controls (97.2 ± 61.1). UPSIT and FM scores were correlated in the control (r = -0.305; P = 0.002) and the IPD group (r = -0.303; P = 0.006) but not among mutation carriers. First, we confirmed olfaction and color discrimination to be impaired in IPD and suggest olfaction to be a premotor sign. Second, olfaction differed between carriers with one and two mutations in Parkin/PINK1-associated PD. Third, olfaction and color discrimination impairment do not necessarily evolve in parallel.
Original languageEnglish
JournalMovement Disorders
Volume25
Issue number15
Pages (from-to)2665-9
Number of pages5
ISSN0885-3185
DOIs
Publication statusPublished - 15 Nov 2010

    Research areas

  • Aged, Color Perception, Color Vision Defects, Discrimination (Psychology), Female, Genetic Testing, Humans, Male, Middle Aged, Mutation, Olfaction Disorders, Parkinson Disease, Smell, Statistics, Nonparametric, alpha-Synuclein

ID: 33437808