Iori Kawasaki1, Toru Baba2, Atsushi Takeda3, Etsuro Mori1. 1. Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Japan. 2. Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Japan. Electronic address: t-baba@med.tohoku.ac.jp. 3. Department of Neurology, National Hospital Organization Sendai-Nishitaga Hospital, Japan.
Abstract
BACKGROUND: Hyposmia is a common non-motor symptom in Parkinson's disease (PD). However, patients with PD are sometimes unaware of their olfactory dysfunction, resulting in an under-diagnosis of this symptom. To determine whether the loss of awareness of hyposmia results from cognitive impairment in patients with PD, we investigated the relationship between the degree of hyposmia self-awareness and the cognitive status of non-demented PD patients. METHODS: Thirty-one non-demented patients with PD and 20 healthy controls (HC) were assessed via a self-reported olfactory questionnaire and an odor identification test. PD patients were sub-classified as having mild cognitive impairment (PD-MCI) or as cognitively normal (PD-CN) (according to the current PD-MCI criteria). We compared the degree of hyposmia self-awareness between the PD-MCI and PD-CN groups. RESULTS: The PD-MCI group scored the lowest on the odor identification test among all groups, whereas PD-MCI patients tended to rate their olfactory function higher on the self-reported olfactory questionnaire than PD-CN patients. Differences in the scores of subjective and objective olfactory measures between the PD-MCI and PD-CN groups were significant (p = 0.0069). CONCLUSIONS: The loss of awareness of hyposmia is closely associated with mild cognitive impairment (MCI) in PD patients.
BACKGROUND:Hyposmia is a common non-motor symptom in Parkinson's disease (PD). However, patients with PD are sometimes unaware of their olfactory dysfunction, resulting in an under-diagnosis of this symptom. To determine whether the loss of awareness of hyposmia results from cognitive impairment in patients with PD, we investigated the relationship between the degree of hyposmia self-awareness and the cognitive status of non-demented PDpatients. METHODS: Thirty-one non-demented patients with PD and 20 healthy controls (HC) were assessed via a self-reported olfactory questionnaire and an odor identification test. PDpatients were sub-classified as having mild cognitive impairment (PD-MCI) or as cognitively normal (PD-CN) (according to the current PD-MCI criteria). We compared the degree of hyposmia self-awareness between the PD-MCI and PD-CN groups. RESULTS: The PD-MCI group scored the lowest on the odor identification test among all groups, whereas PD-MCI patients tended to rate their olfactory function higher on the self-reported olfactory questionnaire than PD-CN patients. Differences in the scores of subjective and objective olfactory measures between the PD-MCI and PD-CN groups were significant (p = 0.0069). CONCLUSIONS: The loss of awareness of hyposmia is closely associated with mild cognitive impairment (MCI) in PDpatients.
Authors: R Durcan; L Wiblin; R A Lawson; T K Khoo; A J Yarnall; G W Duncan; D J Brooks; N Pavese; D J Burn Journal: Eur J Neurol Date: 2019-03-01 Impact factor: 6.089