Kristian Varden Gjerde1,2, Bernd Müller2,3, Geir Olve Skeie2,3, Jörg Assmus4, Guido Alves5,6,7, Ole-Bjørn Tysnes2,3. 1. Division of Psychiatry, Haukeland University Hospital, Bergen, Norway. 2. Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway. 3. Department of Neurology, Haukeland University Hospital, Bergen, Norway. 4. Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway. 5. Department of Neurology, Stavanger University Hospital, Stavanger, Norway. 6. The Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway. 7. Department of Mathematics and Natural Sciences, University of Stavanger, Stavanger, Norway.
Abstract
OBJECTIVES: Olfactory dysfunction has been related to cognitive deficits in Parkinson's disease (PD), but evidence is conflicting and little is known about the relationship between these symptoms in early PD. Our objective was to study the association between smell deficits measured with a simple odor identification test at diagnosis of PD and the subsequent risk of cognitive decline. MATERIALS & METHODS: One hundred and ninety two PD patients from a population-based study were examined at time of diagnosis, before initiation of dopaminergic treatment, with follow-up of 177 patients after 3 years, 162 patients after 5 years and 146 patients after 7 years. Cognitive function was assessed repeatedly with tests of global cognition, verbal memory, visuospatial abilities, processing speed, and executive function. Olfactory function was tested with a simple odor identification test at baseline. Associations between outcome measures and hyposmia were assessed by linear mixed effects models. RESULTS: After 7 years, there were significant differences in global cognition (B: 1.96 (95% CI: 0.68, 3.24), P = 0.0031), verbal memory including immediate recall (B: 5.36 (95% CI: 2.04, 8.67), P = 0.0018) and delayed recall (B: 1.55 (95% CI: 0.51, 2.59), P = 0.0041) and word reading speed (B: 6.90 (95% CI: 2.17, 11.63), P = 0.0048) between hyposmic and normosmic PD patients. CONCLUSIONS: The decline of cognitive function in early PD is more rapid in patients with hyposmia at diagnosis, compared to normosmic ones. A simple smell test may contribute to identify patients at risk of accelerated decline in global cognition, verbal memory, and processing speed within the first 7 years from diagnosis.
OBJECTIVES: Olfactory dysfunction has been related to cognitive deficits in Parkinson's disease (PD), but evidence is conflicting and little is known about the relationship between these symptoms in early PD. Our objective was to study the association between smell deficits measured with a simple odor identification test at diagnosis of PD and the subsequent risk of cognitive decline. MATERIALS & METHODS: One hundred and ninety two PDpatients from a population-based study were examined at time of diagnosis, before initiation of dopaminergic treatment, with follow-up of 177 patients after 3 years, 162 patients after 5 years and 146 patients after 7 years. Cognitive function was assessed repeatedly with tests of global cognition, verbal memory, visuospatial abilities, processing speed, and executive function. Olfactory function was tested with a simple odor identification test at baseline. Associations between outcome measures and hyposmia were assessed by linear mixed effects models. RESULTS: After 7 years, there were significant differences in global cognition (B: 1.96 (95% CI: 0.68, 3.24), P = 0.0031), verbal memory including immediate recall (B: 5.36 (95% CI: 2.04, 8.67), P = 0.0018) and delayed recall (B: 1.55 (95% CI: 0.51, 2.59), P = 0.0041) and word reading speed (B: 6.90 (95% CI: 2.17, 11.63), P = 0.0048) between hyposmic and normosmic PDpatients. CONCLUSIONS: The decline of cognitive function in early PD is more rapid in patients with hyposmia at diagnosis, compared to normosmic ones. A simple smell test may contribute to identify patients at risk of accelerated decline in global cognition, verbal memory, and processing speed within the first 7 years from diagnosis.
Authors: Christine Lo; Siddharth Arora; Yoav Ben-Shlomo; Thomas R Barber; Michael Lawton; Johannes C Klein; Sofia Kanavou; Annette Janzen; Elisabeth Sittig; Wolfgang H Oertel; Donald G Grosset; Michele T Hu Journal: Neurology Date: 2021-02-24 Impact factor: 9.910
Authors: Claudia Carrarini; Mirella Russo; Fedele Dono; Martina Di Pietro; Marianna G Rispoli; Vincenzo Di Stefano; Laura Ferri; Filomena Barbone; Michela Vitale; Astrid Thomas; Stefano Luca Sensi; Marco Onofrj; Laura Bonanni Journal: Biomolecules Date: 2019-08-20
Authors: Xiuli Dan; Noah Wechter; Samuel Gray; Joy G Mohanty; Deborah L Croteau; Vilhelm A Bohr Journal: Ageing Res Rev Date: 2021-07-27 Impact factor: 11.788
Authors: Victoria Van Regemorter; Thomas Hummel; Flora Rosenzweig; André Mouraux; Philippe Rombaux; Caroline Huart Journal: Front Neurosci Date: 2020-02-21 Impact factor: 4.677