ArticleBrain sciences2021
Odor Identification and Regional Gray Matter Atrophy in Patients with Alzheimer's Disease, Parkinson's Disease, and the Healthy Elderly: A Cross-Sectional Structural MRI Study.
Article in Brain sciences, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.
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Who cites it
6 citing papers in PubMed, 1 synthesis or guideline pooled it, 7 citations in OpenAlex.
- Disparity of smell tests in Alzheimer's disease and other neurodegenerative disorders: a systematic review and meta-analysis.Frontiers in aging neuroscience · 2023Pooled it
- Association of impaired olfactory identification with prevalent mild cognitive impairment and regional brain atrophy: the Hisayama Study.Psychiatry and clinical neurosciences · 2025Article
- Odor induced functional connectivity alteration of POC-anterior frontal cortex-medial temporal cortex in patients with mild cognitive impairment.Frontiers in aging neuroscience · 2025Article
- Correlation Between Cortical Thickness Abnormalities of the Olfactory Sulcus and Olfactory Identification Disorder and Persistent Auditory Verbal Hallucinations in Chinese Patients With Chronic Schizophrenia.Schizophrenia bulletin · 2024Article
- Altered functional connectivity of primary olfactory cortex-hippocampus-frontal cortex in subjective cognitive decline during odor stimulation.Human brain mapping · 2024Article
- Olfactory Dysfunction in Parkinson's Disease, Its Functional and Neuroanatomical Correlates.NeuroSci · 2023Review
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 1 country.
Funding
Abstract
Multiple associations between impaired olfactory performance and regional cortical and deep gray matter atrophy have been reported in separate studies of patients with Alzheimer's disease (AD), Parkinson's disease (PD), and of the healthy elderly. We aimed to evaluate such possible associations among these populations in a unified manner. Twenty AD, twenty PD patients' and twenty healthy age- and sex-matched controls' odor identification performance was assessed with the Lithuanian adaptation of the Sniffin' Sticks 12 odor identification test, followed by morphometric gray matter analysis by MRI using FreeSurfer. AD patients had significantly lower cognitive performance than both PD patients and the healthy elderly, as evaluated with the Mini-Mental State Examination (MMSE). Odor identification performance was significantly worse in AD and PD patients compared with the healthy elderly; AD patients performed slightly worse than PD patients, but the difference was not statistically significant. Among patients with AD, worse odor identification performance was initially correlated with atrophy of multiple cortical and deep gray matter regions known to be involved in olfactory processing, however, only two measures-decreased thicknesses of the right medial and left lateral orbitofrontal cortices-remained significant after adjustment for possible confounders (age, MMSE score, and global cortical thickness). Among patients with PD and the healthy elderly we found no similar statistically significant correlations. Our findings support the key role of the orbitofrontal cortex in odor identification among patients with AD, and suggest that correlations between impaired odor identification performance and regional gray matter atrophy may be relatively more pronounced in AD rather than in PD.
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