Evidence map›Paper›PMID 30715632›Full record

SynthesisNeurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology2019

Plasma alpha-synuclein levels in patients with Parkinson's disease: a systematic review and meta-analysis.

Anastasia Bougea, Leonidas Stefanis, George P Paraskevas, Evangelia Emmanouilidou, Kostas Vekrelis, Elisabeth Kapaki

Abstract readMeta-AnalysisSystematic Review
PubMed Publisher
In one paragraph

Synthesis in Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 47 papers, 4 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
47citing papers in PubMed, 4 pooled it
7.8field-weighted citation impact, top 2% 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

47 citing papers in PubMed, 4 syntheses or guidelines pooled it, 80 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Association of gender and age at onset with glucocerebrosidase associated Parkinson's disease: a systematic review and meta-analysis.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2021
    Pooled it
  4. Salivary alpha-synuclein as a biomarker for Parkinson's disease: a systematic review.Journal of neural transmission (Vienna, Austria : 1996) · 2019
    Pooled it
  5. Trial
  6. Review
  7. Article
  8. Article
  9. Review
  10. Review
  11. Article
  12. Article
  13. Review
  14. Article
  15. Review
  16. Article
  17. Review
  18. Article
  19. Review
  20. Review
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

6 authors at 2 institutions in 1 country.

Anastasia BougeaNeurochemistry laboratory, 1st Department of Neurology and Movement Disorders, Medical School, Aeginition Hospital, National and Kapodistrian University of Athens, 72-74 Vasilissis Sofias Avenue, 11528, Athens, Greece. abougea@med.uoa.gr.ORCID http://orcid.org/0000-0003-3006-8711
Leonidas StefanisNeuroscience laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
George P ParaskevasNeurochemistry laboratory, 1st Department of Neurology and Movement Disorders, Medical School, Aeginition Hospital, National and Kapodistrian University of Athens, 72-74 Vasilissis Sofias Avenue, 11528, Athens, Greece.
Evangelia EmmanouilidouNeuroscience laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
Kostas VekrelisNeuroscience laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
Elisabeth KapakiNeurochemistry laboratory, 1st Department of Neurology and Movement Disorders, Medical School, Aeginition Hospital, National and Kapodistrian University of Athens, 72-74 Vasilissis Sofias Avenue, 11528, Athens, Greece.
Biomedical Research Foundation of the Academy of Athens · GRNational and Kapodistrian University of Athens · GR

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveTo date, there are no definitive biomarkers for diagnose Parkinson's disease (PD). The detection of α-synuclein (α-Syn) in plasma of PD patients has yielded promising but inconclusive results. To determine the performance of α-Syn as a diagnostic biomarker of PD, we used a meta-analysis.

methodsWe identified 173 studies through a systematic literature review. From those, only studies reporting data on total α-Syn levels were included in the meta-analysis (10 publications, 1302 participants). Quality of studies was assessed by Newcastle-Ottawa scale.

resultsThe α-Syn levels were significantly higher in PD patients than healthy controls (standardized mean difference [SMD] = 0.778, 95% confidence interval = 0.284 to 1.272, p = 0.002). Similar results were found after omitting any individual study from meta-analysis, with SMD ranges from 0.318 (95% CI = 0.064 to 0.572, p = 0.014) to 0.914 (95% CI = 0.349 to 1.480, p = 0.002). According to meta-regression analysis, increased mean patients age (slope = - 0.232, 95% CI = - 0.456 to - 0.008, p = 0.042), increased total number of participants (slope = - 0.007, 95% CI = - 0.013 to - 0.0004, p = 0.038), and increased percentage of males (slope = - 6.444, 95% CI = - 10.841 to - 2.047, p = 0.004) were associated with decreased SMD of α-Syn levels across studies. We did not find any significant association between the SMD in α-Syn levels and disease duration, disease severity, and quality of studies. Most of studies applied ELISA assays.

conclusionTotal plasma α-Syn levels were higher in PD patients than controls. Analytical factors were important limitations.

Indexed as

alpha-SynucleinBiomarkersHumansParkinson Diseasealpha-SynucleinBiomarkersSNCA protein, humanBiomarkerMeta-analysisMeta-regressionParkinson’s disease (PD)Plasmaα-Synuclein

Identifiers

PMID30715632
OpenAlexW2912023154

What OpenQuestion holds

Textmetadata
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.