ArticleAnnals of clinical and translational neurology2014
Olfactory identification in LRRK2 G2019S mutation carriers: a relevant marker?
Article in Annals of clinical and translational neurology, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers.
What it found
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The trial behind it
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Who cites it
25 citing papers in PubMed, 42 citations in OpenAlex.
- Updated Percentiles for the University of Pennsylvania Smell Identification Test in Adults 50 Years of Age and Older.Neurology · 2023Trial
- Analysis of α-synuclein seed amplification assay in carriers ofJournal of Parkinson's disease · 2026Article
- More Than Rapid Eye Movement Sleep Behavior Disorder: Sleep Differences in Parkinson's Disease LRRK2 and GBA Genotypes.Journal of sleep medicine · 2025Article
- Heartbeat signature for predicting motor and non-motor involvement among nonparkinsonian LRRK2 G2019S mutation carriers.Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2025Article
- Article
- LRRK2-Associated Parkinsonism With and WithoutmedRxiv : the preprint server for health sciences · 2024Article
- Neurons, Nose, and Neurodegenerative Diseases: Olfactory Function and Cognitive Impairment.International journal of molecular sciences · 2023Review
- A Remote Longitudinal Observational Study of Individuals at Genetic Risk for Parkinson Disease: Baseline Results.Neurology. Genetics · 2022Article
- Association of Olfactory Performance With Motor Decline and Age at Onset in People With Parkinson Disease and theNeurology · 2022Article
- Who to Enroll in Parkinson Disease Prevention Trials? The Case for Genetically At-Risk Cohorts.Neurology · 2022Review
- Molecular mechanisms defining penetrance ofMedizinische Genetik : Mitteilungsblatt des Berufsverbandes Medizinische Genetik e.V · 2022Article
- A Practical Approach to Early-Onset Parkinsonism.Journal of Parkinson's disease · 2022Review
- Profiling Non-motor Symptoms in Monogenic Parkinson's Disease.Frontiers in aging neuroscience · 2020Review
- Olfactory Dysfunction in Familial and Sporadic Parkinson's Disease.Frontiers in neurology · 2020Review
- Hierarchical Data-Driven Analysis of Clinical Symptoms Among Patients With Parkinson's Disease.Frontiers in neurology · 2019Article
- Increased substantia nigra echogenicity in LRRK2 family members without mutations.Movement disorders : official journal of the Movement Disorder Society · 2018Article
- Application of the Movement Disorder Society prodromal criteria in healthy G2019S-LRRK2 carriers.Movement disorders : official journal of the Movement Disorder Society · 2018Article
- Olfactory Dysfunction in Neurodegenerative Diseases.Current allergy and asthma reports · 2018Review
- Progression in the LRRK2-Asssociated Parkinson Disease Population.JAMA neurology · 2018Article
- Clinical Heterogeneity AmongFrontiers in aging neuroscience · 2018Article
Corrections and comments
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Authors and funding
14 authors at 6 institutions in 2 countries.
Funding
Abstract
objectiveOlfactory impairment is a potential marker for impending phenoconversion to Parkinson disease (PD) that may precede the development of disease by several years. Because of low specificity, it may be of greater predictive value in those with genetic mutations and its potential as a marker for developing LRRK2 PD should be evaluated.
methodsWe examined olfactory identification in 126 LRRK2 G2019S mutation carriers with PD, 125 mutation carriers not manifesting PD, 126 noncarriers with idiopathic PD, 106 noncarrier family members without PD, and 35 unrelated controls. We compared olfactory performance and performed mixture modeling to identify possible subgroups of olfactory performance in LRRK2 PD and nonmanifesting carriers.
resultsAdjusting for sex, age, cognitive score, site, and smoking history, LRRK2 PD had better olfactory scores compared to idiopathic PD (mean olfaction difference: -3.7, P < 0.001), and both LRRK2 PD and idiopathic PD had worse olfaction than controls (-12.8, -9.1, both P < 0.001). LRRK2 PD were less likely to be hyposmic than idiopathic PD (54.8% vs. 80.2%, P < 0.001). Nonmanifesting carriers and noncarrier family members did not differ. Mixture model analysis identified three classes in the LRRK2 PD and nonmanifesting carriers, suggesting that there are subgroups with poor olfactory identification in both LRRK2 PD and nonmanifesting carriers.
interpretationTherefore, olfactory identification deficit is less likely to be an obligate feature in LRRK2 PD than idiopathic PD, and while a relevant marker in some, a subset of carriers who eventually phenoconvert may proceed directly to PD without prior impaired olfaction.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.