Circulating Ghrelin as a Biomarker for Dementia (GDEM3)

July 3, 2026 updated by: Swansea University

The primary objective of this study will explore whether circulating acyl-ghrelin (AG) and unacylated-ghrelin (UAG) are reduced in neurodegenerative disease associated with cognitive impairment. It will focus on validating pilot data generated following the analysis of Parkinson's disease (PD), Parkinson's disease dementia (PDD) and healthy cohorts (IRAS project ID: 250933). In addition to the advantages of study replication we will extend the analysis to include two further patient groups that are associated with cognitive impairments, namely, Alzheimer's dementia (AD) and dementia with Lewy bodies (DLB). This study will increase confidence in the replication of our findings.

This will be a cross-sectional study using peripheral venous blood.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

85

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

60 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Age > 60 years
  • Subject or carer / legal representative is willing to sign consent document

Specific criteria for each group;

Parkinson's Disease

  • PD diagnosed by a movement disorder specialist and meets the diagnosis of PD
  • MoCA > 26/30
  • No evidence of cognitive symptoms causing functional impairment

Parkinson's Disease Dementia

  • PD diagnosed by a movement disorder specialist
  • Duration of motor symptoms > 1 year
  • Meets MDS task force criteria for PDD
  • MoCA < 21/30

Dementia with Lewy Bodies

  • Meets criteria for probable DLB as defined by the 4th report of the DLB consortium

Alzheimer's Disease

  • Meets criteria for probable AD dementia (consistent with NIA/AA core clinical criteria for probable AD dementia)

Exclusion Criteria:

  • Age < 60 years
  • Current major depression
  • Use of anti-psychotic medication
  • Type I or Type II diabetes mellitus (DM) (excluding diet-controlled DM)
  • Tobacco use
  • BMI <15.0 kg/m2
  • BMI > 30 kg/m2
  • Comorbid gastrointestinal disease i.e. includes Coeliac, active Inflammatory Bowel Disease (Colitis), evidence for active gastric ulcers within the last 12 months, but excludes gastroesophageal reflux and hiatus hernia.
  • >5 kg weight change over the preceding 3 months (determined by researcher from previous clinic visit and discussion with partner/carer)
  • Significant active comorbidity
  • Difficult venous access
  • Vagotomy

Additional disease specific exclusions;

  • Parkinson's Disease exclusion criteria
  • Evidence of dementia or mild cognitive impairment
  • Deep brain stimulation (DBS)
  • Use of Duodopa

Parkinson's Disease Dementia exclusion criteria

  • Dementia within 12 months of diagnosis of PD
  • DBS

Dementia with Lewy bodies exclusion criteria

  • Onset of motor Parkinsonism symptoms greater than 12 months prior to dementia diagnosis

Alzheimer's dementia exclusion criteria

  • Presence of PD, PDD, DLB, or Frontotemporal Dementia (FTD)

Controls exclusion criteria

  • Evidence of parkinsonism
  • Evidence of dementia or mild cognitive impairment
  • MoCA <26/30

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Healthy control
Venous blood collection
Diagnostic test: Venous blood collection
Participants will undergo venous blood collection following an overnight fast and 5, 60 and 180 minutes following food intake.
Experimental: Parkinson's disease
Venous blood collection
Diagnostic test: Venous blood collection
Participants will undergo venous blood collection following an overnight fast and 5, 60 and 180 minutes following food intake.
Experimental: Parkinson's disease dementia
Venous blood collection
Diagnostic test: Venous blood collection
Participants will undergo venous blood collection following an overnight fast and 5, 60 and 180 minutes following food intake.
Experimental: Dementia with Lewy Bodies
Venous blood collection
Diagnostic test: Venous blood collection
Participants will undergo venous blood collection following an overnight fast and 5, 60 and 180 minutes following food intake.
Experimental: Alzheimer's disease
Venous blood collection
Diagnostic test: Venous blood collection
Participants will undergo venous blood collection following an overnight fast and 5, 60 and 180 minutes following food intake.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Ghrelin ratio in PD and PDD
Time Frame: Through study completion, an average of 1 year
Quantification of circulating ghrelin peptides
Through study completion, an average of 1 year

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Ghrelin ratio in AD and DLB
Time Frame: Through study completion, an average of 1 year
Quantification of circulating ghrelin peptides
Through study completion, an average of 1 year
Immune cell function in PD, PDD, DLB and AD.
Time Frame: Through the study, an average of 1 year.
Quantification of Peripheral Blood Mononuclear Cell (PBMC) function, via RNA-assays and protein-immunoassays from control, PD, PDD, DLB and AD donors.
Through the study, an average of 1 year.
LEAP2 levels in PD, PDD, DLB and AD
Time Frame: Through study completion, an average of 1 year.
Quantification of LEAP2 via immunoassay in blood plasma collected from control, PD, PDD, AD and DLB donors.
Through study completion, an average of 1 year.
Insulin in control, PD, PDD, DLB and AD.
Time Frame: Through study completion, an average of 1 year.
Quantification of insulin via immunoassay in blood plasma collected from control, PD, PDD, DLB and AD donors.
Through study completion, an average of 1 year.
Proteomics of control, PD, PDD, AD and DLB donor samples.
Time Frame: Through the study, an average of 1 year.
Quantification of proteins via Next Generation Sequencing (NGS)-based proteomics.
Through the study, an average of 1 year.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Swansea University

Collaborators

Newcastle University

Investigators

  • Principal Investigator: Jeffrey S Davies, BSc, PhD, Swansea University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 15, 2022

Primary Completion (Actual)

February 6, 2025

Study Completion (Actual)

March 31, 2026

Study Registration Dates

First Submitted

May 20, 2021

First Submitted That Met QC Criteria

May 18, 2022

First Posted (Actual)

May 19, 2022

Study Record Updates

Last Update Posted (Actual)

July 8, 2026

Last Update Submitted That Met QC Criteria

July 3, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 288862

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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