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Meta-analyses on prevalence of selected Parkinson's nonmotor symptoms before and after diagnosis
Open accessAbstract
BACKGROUND: Nonmotor symptoms are common among patients with Parkinson's disease (PD) and some may precede disease diagnosis. METHODS: We conducted a meta-analysis on the prevalence of selected nonmotor symptoms before and after PD diagnosis, using random-effect models. We searched PubMed (1965 through October/November 2012) for the following symptoms: hyposmia, constipation, rapid eye movement sleep behavior disorder, excessive daytime sleepiness, depression, and anxiety. Eligible studies were publications in English with original data on one or more of these symptoms. RESULTS: The search generated 2,373 non-duplicated publications and 332 met the inclusion criteria, mostly (n = 320) on symptoms after PD diagnosis. For all symptoms, the prevalence was substantially higher in PD cases than in controls, each affecting over a third of the patients. Hyposmia was the most prevalent (75.5% in cases vs. 19.1% in controls), followed by constipation (50% vs. 17.7%), anxiety (39.9% vs. 19.1%), rapid eye movement sleep behavior disorder (37.0% vs. 7.0%), depression (36.6% vs. 14.9%), and excessive daytime sleepiness (33.9% vs. 10.5%). We observed substantial heterogeneities across studies and meta-regression analyses suggested that several factors might have contributed to this. However, the prevalence estimates were fairly robust in several sensitivity analyses. Only 20 studies had data on any symptoms prior to PD diagnosis, but still the analyses revealed higher prevalence in future PD cases than in controls. CONCLUSION: These symptoms are common among PD patients both before and after diagnosis. Further studies are needed to understand the natural history of nonmotor symptoms in PD and their etiological and clinical implications.
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“Some of these symptoms may precede the classical motor symptoms by several years (Abbott et al., 2001;Chen et al., 2015;Gao et al., 2011)”
From The Gut-Brain Axis in Parkinson’s Disease: Possibilities for Food-Based Therapies (2017) · cites this paper as Chen et al., 2015
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Metadata
- Authors
- Chen, H., Zhao, E. J., Zhang, W., Lu, Y., Liu, R., Huang, X., Ciesielski-Jones, A. J., Justice, M. A., Cousins, D. S., & Peddada, S.
- Affiliations
- National Institutes of Health (US)
- Social and Scientific Systems (United States) (US)
- Pennsylvania State University (US)
- National Institute of Environmental Health Sciences (US)
- Corresponding author
- Chen, Honglei
- ORCID
- Venue
- Translational Neurodegeneration
- Published
- 2015-01-08
- Volume
- 4
- Issue
- 1
- Pages
- 1-1
- ISSN
- 2047-9158 (ISSN-L)
- PMC
- PMC4322463
- OpenAlex
- W2126909058
- Cited by
- 212
- References
- 40
- Citations by year
- 2026: 11 · 2025: 22 · 2024: 16 · 2023: 21 · 2022: 20 · 2021: 26 · 2020: 20 · 2019: 16 · 2018: 21 · 2017: 28 · 2016: 7 · 2015: 4
- FWCI
- 14.10
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- Translational Neurodegeneration (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (1z01es101986-03, Z01-ES101986)
- National Institute of Neurological Disorders and Stroke (U01NS082151)
- National Institute of Environmental Health Sciences
- Topics
- Health Sciences › Medicine › Clinical Neurology › Parkinson's Disease Mechanisms and Treatments
- Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
- Health Sciences › Medicine › Clinical Neurology › Deep Brain Stimulation and Movement Disorders
- Keywords
- Parkinson's disease, non-motor symptoms, hyposmia, constipation, REM sleep behavior disorder, excessive daytime sleepiness, depression, anxiety, symptom prevalence, preclinical Parkinson's disease
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