An observational study in Parkinson Disease, sponsored by University of Aberdeen. Completed at 1 site in United Kingdom. Open to participants aged 18 Years to 110 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-31.
Sponsored by University of Aberdeen · Observational
The aim of this study is to investigate the link between gut health and Parkinson's disease
Parkinson's disease (PD) is a common, age-related neurological condition, affecting approximately 145,000 people in the United Kingdom. Diagnostic symptoms include stiffness, tremor, unsteadiness and slow movements. Interestingly, while PD is usually considered to be a neurological condition, pathological changes occur in the gut years before diagnosis, often causing constipation. As such, the gut has attracted attention as a possible therapeutic target.
Previous studies have shown different profiles of gut bacteria and the short chain fatty acids (SCFAs) they produce in people with PD. There is evidence these changes might be significant to the disease course, as faecal transplants from people with PD worsened symptoms in a mouse model of PD. The mechanism for this is unclear, but changes in SCFAs and gut wall inflammation, have both been suggested. Studies so far have compared gut bacteria in people with and without PD, however, as the healthy controls often don't have constipation, it is unclear if the differences seen are due to PD itself or the associated constipation.
This pilot study aims to determine differences in the frequency of gut micro-organisms (bacteria, fungi and archaea) and gut function, other than those caused by constipation. 40 participants with a new diagnosis of PD will be recruited from Movement Disorder clinics within National Health Service (NHS) Grampian. 40 healthy (non-PD) controls will be recruited from the PD participants households (whenever feasible). All 80 participants will be clinically assessed and asked to provide two stool samples. The samples will be analysed for the frequency of gut micro-organisms, changes in gut function (short chain fatty acid concentrations) and gut inflammation (calprotectin concentrations).
The aim of this pilot study is to determine the key differences in gut micro-organisms in PD compared to controls, which may have a role in disease progression. It is likely that the results of this proof of concept study would need to be confirmed in a larger study before the investigators are able to plan an intervention trial, such as testing a prebiotic product, with the aim of normalising gut micro-organisms, and potentially modifying the disease course.
4,487 studies on the registry are indexed under Parkinson Disease; 1,082 are open to participants now.
This study's enrollment of 30 is below the median of 96 across 1,057 observational studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →University of Aberdeen is the lead sponsor of 170 studies on the registry; 23 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Parkinson disease group: potential participants will be invited into the study if they have recently been diagnosed with Parkinson's disease and have not yet started medication for the condition
Control group: spouses or other household contacts will be invited to the study
Participants with Parkinson's disease 2. Community-dwelling patients with newly diagnosed PD who have not yet started medication for Parkinson's disease.
Control Participants
1. Healthy (non-Parkinsonian) members of the participants household will be invited to act as controls.
Exclusion Criteria:
Participants with newly diagnosed Parkinson's disease
Control subjects - will be selected from household/spousal contacts of the participants with Parkinson's disease
Micro-organism prevalence in stool sample
Stool samples will be posted to the Rowett Institute, and processed and analysed in the laboratory at The Rowett Institute, University of Aberdeen. The samples will be analysed for water content and microbial RNA/DNA will be extracted for genome analysis. When the analysis is complete, the faecal samples will be destroyed.
Time frame: Baseline
Micro-organism prevalence in stool sample
Stool samples will be posted to the Rowett Institute, and processed and analysed in the laboratory at The Rowett Institute, University of Aberdeen. The samples will be analysed for water content and microbial RNA/DNA will be extracted for genome analysis. When the analysis is complete, the faecal samples will be destroyed.
Time frame: Within two months of baseline
Analysis of stool samples for concentration of short chain fatty acids
Stool samples will be posted to the Rowett Institute via Royal Mail. Samples will be processed and analysed in the laboratory at The Rowett Institute, University of Aberdeen. The samples will be analysed for short chain fatty acid concentration (µmol/g).
Time frame: Baseline
Analysis of stool samples for concentration of calprotectin
Stool samples will be posted to the Rowett Institute via Royal Mail. Samples will be processed and analysed in the laboratory at The Rowett Institute, University of Aberdeen. The samples will be analysed for short calprotectin concentration (µg/g).
Time frame: Baseline
Analysis of stool samples for markers of gut function (short chain fatty acids and calprotectin)
Stool samples will be posted to the Rowett Institute via Royal Mail. Samples will be processed and analysed in the laboratory at The Rowett Institute, University of Aberdeen. The samples will be analysed for short chain fatty acid (SCFA) profile and calprotectin concentration. When the analysis is complete, the faecal samples will be destroyed.
Time frame: Within two months of the baseline sample
To assess the extent of swallowing problems (dysphagia) by a questionnaire
Participants will be asked to completed a standardized swallowing questionnaire (Swallowing Disturbance Questionnaire), which has been validated in people with Parkinson's disease. The score ranges from 0-43, with a higher score increasing the likelihood for a swallowing problem, which would require further investigation
Time frame: Baseline
To assess the extent of swallowing problems using a standardized swallowing test
Participants will be asked to drink 150 millilitres of cold water from a clear cup. The rater will sit at their side and record them on video for later analysis. The speed in ml/second and volume per average swallow will be recorded by determining if any residual volume is left, the number of seconds to complete the task and the number of swallows. The test will be terminated if there is any indication of aspiration of liquid.
Time frame: Baseline
To assess the extent of swallowing problems using a standardized swallowing test
Participants will be asked to drink 150 millilitres of cold water from a clear cup. The rater will sit at their side and record them on video for later analysis. The speed in ml/second and volume per average swallow will be recorded by determining if any residual volume is left, the number of seconds to complete the task and the number of swallows. The test will be terminated if there is any indication of aspiration of liquid.
Time frame: Four weeks after the baseline assessment
To assess taste sensation using a simple test
Participants taste recognition will be assessed using standardized taste strips from Burghart (sweet, salty, sour and bitter)
Time frame: Baseline
To assess dietary intake over a 24 hour period using a structured interview
Following the initial visit, the participant will receive a phone call from a trained member of the team to perform a 24-hour dietary recall interview. This is a structured interview where participants are asked to recall all food and beverage consumption over a 24-hour period and further questions are asked to determine further details, including portion size and ingredients and cooking methods used. The whole interview usually takes 20 to 60 minutes.
Time frame: Baseline
To assess the reliability of bio-impedence analysis in determining fat mass in older adults with and without PD
Fat mass in kilograms will be measured using a seca mBCA 525 bio-impedence machine.
Time frame: Baseline
To assess the reliability of bio-impedence analysis in determining fat mass in older adults
Fat mass in kilograms will be measured using a seca mBCA 525 bio-impedence machine.
Time frame: Four weeks after baseline assessment
To assess the reliability of bio-impedence analysis in determining fat mass in older adults
Fat free mass in kilograms will be measured using a seca mBCA 525 bio-impedence machine.
Time frame: Baseline
To assess the reliability of bio-impedence analysis in determining fat mass in older adults
Fat free mass in kilograms will be measured using a seca mBCA 525 bio-impedence machine.
Time frame: Four weeks after the baseline assessment
Plan to share: No
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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University of Aberdeen