Evidence map›Paper›PMID 33361610›Full record

ReviewJournal of Parkinson's disease2021

Infection and Risk of Parkinson's Disease.

Richard J Smeyne, Alastair J Noyce, Matthew Byrne, Rodolfo Savica, Connie Marras

Open access · hybridAbstract readReview
In one paragraph

Review in Journal of Parkinson's disease, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 84 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
84citing papers in PubMed, 2 pooled it
4.8field-weighted citation impact, top 4% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

84 citing papers in PubMed, 2 syntheses or guidelines pooled it, 134 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Review
  4. Focused Ultrasound for the Treatment of Circuit and Molecular Pathology in Parkinson's Disease.Movement disorders : official journal of the Movement Disorder Society · 2026
    Review
  5. Review
  6. Review
  7. Article
  8. Article
  9. Article
  10. Article
  11. Review
  12. Review
  13. Clinical Characteristics of Parkinsonism in HTLV-1-Associated Myelopathy.Annals of clinical and translational neurology · 2025
    Article
  14. Neuroimmune pathophysiology of long COVID.Psychiatry and clinical neurosciences · 2025
    Review
  15. Article
  16. Article
  17. Review
  18. Review
  19. Review
  20. Article

24 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 4 institutions in 3 countries.

Richard J SmeyneDepartment of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA.
Alastair J NoycePreventive Neurology Unit, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK.
Matthew ByrneDepartment of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA.
Rodolfo SavicaDepartment of Neurology, Mayo Clinic, Rochester, Minnesota and Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.
Connie MarrasThe Edmond J Safra Program in Parkinson's disease, Toronto Western Hospital and the University of Toronto, Toronto, Canada.
Thomas Jefferson University · USMayo Clinic in Florida · USQueen Mary University of London · GBUniversity of Toronto · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Parkinson's disease (PD) is thought to be caused by a combination of genetic and environmental factors. Bacterial or viral infection has been proposed as a potential risk factor, and there is supporting although not entirely consistent epidemiologic and basic science evidence to support its role. Encephalitis caused by influenza has included parkinsonian features. Epidemiological evidence is most compelling for an association between PD and hepatitis C virus. Infection with Helicobacter pylori may be associated not only with PD risk but also response to levodopa. Rapidly evolving knowledge regarding the role of the microbiome also suggests a role of resident bacteria in PD risk. Biological plausibility for the role for infectious agents is supported by the known neurotropic effects of specific viruses, particular vulnerability of the substantia nigra and even the promotion of aggregation of alpha-synuclein. A common feature of implicated viruses appears to be production of high levels of cytokines and chemokines that can cross the blood-brain barrier leading to microglial activation and inflammation and ultimately neuronal cell death. Based on multiple avenues of evidence it appears likely that specific bacterial and particularly viral infections may increase vulnerability to PD. The implications of this for PD prevention requires attention and may be most relevant once preventive treatments for at-risk populations are developed.

Indexed as

Gastrointestinal MicrobiomeBacterial InfectionsHumansParkinson DiseaseVirus DiseasesbacteriaetiologyinfectionParkinson’s diseaseviruses

Identifiers

PMID33361610
PMCPMC7990414
OpenAlexW3117517717

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

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.