Evidence map›Paper›PMID 33972579›Full record

Observational studyScientific reports2021

Salivary caffeine in Parkinson's disease.

Giorgio Leodori, Maria Ilenia De Bartolo, Daniele Belvisi, Alessia Ciogli, Andrea Fabbrini, Matteo Costanzo, Simone Manetto, Antonella Conte, Claudio Villani, Giovanni Fabbrini and 1 more

Open access · goldAbstract readObservational Study
PubMed Full text at PMC Publisher
In one paragraph

Observational study in Scientific reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers.

0numbers the graph read from it
0cells of the map it votes in
11citing papers in PubMed
1.9field-weighted citation impact, top 12% 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

11 citing papers in PubMed, 22 citations in OpenAlex.

  1. Review
  2. Article
  3. Article
  4. Caffeine in Aging Brains: Cognitive Enhancement, Neurodegeneration, and Emerging Concerns About Addiction.International journal of environmental research and public health · 2025
    Review
  5. Article
  6. Review
  7. Article
  8. Glutathione-Mediated Neuroprotective Effect of Purine Derivatives.International journal of molecular sciences · 2023
    Review
  9. Review
  10. Article
  11. Article
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

11 authors at 2 institutions in 1 country.

Giorgio LeodoriIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy.
Maria Ilenia De BartoloIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy.
Daniele BelvisiIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy.
Alessia CiogliDepartment of Chemistry and Drug Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
Andrea FabbriniDepartment of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
Matteo CostanzoDepartment of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
Simone ManettoDepartment of Chemistry and Drug Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
Antonella ConteIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy.
Claudio VillaniDepartment of Chemistry and Drug Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
Giovanni FabbriniIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy.
Alfredo BerardelliIRCCS NEUROMED, Via Atinense, 18, 86077, Pozzilli, Italy. alfredo.berardelli@uniroma1.it.
Sapienza University of Rome · ITIstituto Neurologico Mediterraneo · IT

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

We aimed to investigate salivary caffeine content, caffeine absorption and metabolism in Parkinson's disease (PD) and verify whether salivary caffeine can be used as a biomarker of PD. We enrolled 98 PD patients and 92 healthy subjects. Caffeine and its major metabolite, paraxanthine, were measured in saliva samples collected before and 4 h after the oral intake of caffeine (100 mg). We measured caffeine absorption as the normalized increase in caffeine levels, and caffeine metabolism as the paraxanthine/caffeine ratio. The Movement Disorder Society Unified Parkinson's Disease Rating Scale part III, the Hoehn & Yahr, the presence of motor complications, and levodopa equivalent dose (LED) were assessed and correlated with caffeine levels, absorption, and metabolism. The effects of demographic and environmental features possibly influencing caffeine levels were also investigated. Caffeine levels were decreased in patients with moderate/advanced PD, while caffeine levels were normal in patients with early and de-novo PD, unrelated to caffeine intake. Caffeine absorption and metabolism were normal in PD. Decreased salivary caffeine levels in PD were associated with higher disease severity, longer duration, and the presence of motor complications, no significant association was found with LED. Salivary caffeine decrease correlates with PD progression.

Indexed as

AgedBiomarkersCaffeineCase-Control StudiesFemaleHealthy VolunteersHumansMaleMental Status and Dementia TestsMiddle AgedParkinson DiseaseSalivaSeverity of Illness IndexBiomarkersCaffeine

Identifiers

PMID33972579
PMCPMC8110998
OpenAlexW3161508853

What OpenQuestion holds

Textmetadata
LicenceCC BY
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.