Can increased dietary fibre reduce laxative requirement in PD patients?

ISRCTN ISRCTN33329207
DOI https://doi.org/10.1186/ISRCTN33329207
Secondary identifying numbers 5807
Submission date
18/06/2010
Registration date
18/06/2010
Last edited
30/08/2016
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Urological and Genital Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Patients with kidney disease need dialysis to replace the work their kidneys are not able to do. One of the types of dialysis available is called Peritoneal Dialysis (PD). It relies on a special fluid being drained in and out of the patient’s body. If a PD patient becomes constipated, this fluid cannot drain out properly. As a result, the dialysis process stops working. All PD patients are given laxatives to prevent them from becoming constipated. Rather than rely on laxative medicine, this study aimed to improve the intake of dietary fibre as a means of preventing constipation.

Who can participate?
All adult patients on PD were invited to take part if they were using laxatives regularly and wanted to try an alternative.

What does the study involve?
Patients were randomly put into one of three groups. The first group was given dietary fibre in the form of a white powder that dissolved easily in drinks and soft food. The second group was given a white powder that looked the same but had no fibre. This is called a placebo. These two groups did not know which of the powders they had been given. They were told to mix the powder with any drink or food each day for 4 weeks. They had to start gradually in case the powder caused them any discomfort. They were told to continue taking their usual laxatives until they could tell that the powder was having an effect. They were shown how to measure the effect the powder might be having by looking at their stools. If their stools became looser, they were told to reduce their laxatives but keep going with the powder. The third group were given a special diet chart that listed foods containing dietary fibre that were safe for kidney patients to eat. They were told to try and include six to nine items from the list every day to see if they could improve their intake of dietary fibre using normal food.

What are the possible benefits and risks of participating?
The advantage of taking part would be to use a more natural way of controlling bowel function rather than relying on medication. There were no risks involved with this trial. None of the interventions required patients to make changes to their existing therapeutic dietary advice or their medication.

Where is the study run from?
The study was designed by one of the Renal Dietitians and originally tried out in Portsmouth. It was then extended to include other renal units across England. These were Kings College London, York, Royal Berkshire, Sheffield, Exeter, Truro, Plymouth, Kent and Canterbury. In all cases, the work was carried out by one of the Renal Dietitians on each Unit.

When is the study starting and how long is it expected to run for?
The study ran from March 2009 to August 2010.

Who is funding the study?
The study was funded by a grant from the British Renal Society.

Who is the main contact?
Debbie Sutton, Renal Research Dietitian
Debbie.sutton@porthosp.nhs.uk

Contact information

Mrs Debbie Sutton
Scientific

Portsmouth - Queen Alexandra Hospital
Renal Unit
Portsmouth
PO6 3LY
United Kingdom

Phone +44 23 9228 6000
Email debbie.sutton@porthosp.nhs.uk

Study information

Study designMulticentre randomised interventional treatment trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details below to request a patient information sheet
Scientific titleA multicentre randomised trial to assess whether increased dietary fibre intake (using a fibre supplement or high fibre foods) reduces laxative requirement in free living Peritoneal Dialysis patients
Study objectivesThe main aim of this study is to investigate whether a daily bowel habit of appropriate consistency may be achieved through a higher fibre diet and minimal use of laxatives.

Objectives:
We will conduct the study to:
1. Establish current bowel habits, fibre intake, laxative use and costs, and the prevalence of constipation among all peritoneal dialysis (PD) programme patients
2. Test whether an increase in dietary fibre intake by 6 - 12 g per day (using a fibre supplement or high fibre food) results in improved bowel habits and reduced laxative use
3. Ensure that the treatment has no adverse effects on fluid balance or laboratory parameters (potassium, phosphate)
4. Investigate whether an increased fibre intake improves lipid profile
Ethics approval(s)Portsmouth IOW and SE Hants REC approved on the 18/12/2008 (ref: 08/H0501/123)
Health condition(s) or problem(s) studiedTopic: Renal and Urogenital; Subtopic: Renal and Urogenital (all Subtopics); Disease: Renal
Intervention1. Fibre supplement arm
2. High dietary fibre arm
3. Placebo arm

The length of study period in each arm is 4 weeks.
Intervention typeOther
Primary outcome measureRegular bowel activity, measured once at the end of the 4 week intervention period
Secondary outcome measures1. Has stopped their laxatives
2. Stools equal to 3, 4 or 5 on the Bristol Stool Form

Measured once at the end of the 4 week intervention period.
Overall study start date01/03/2009
Completion date31/08/2010

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participantsPlanned sample size: 100
Key inclusion criteria1. PD patient for minimum 3 months
2. Regular user of laxatives
3. Aged greater than 18 years, either sex
Key exclusion criteriaDoes not meet inclusion criteria
Date of first enrolment01/03/2009
Date of final enrolment31/08/2010

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

Portsmouth - Queen Alexandra Hospital
Portsmouth
PO6 3LY
United Kingdom

Sponsor information

Portsmouth Hospitals NHS Trust (UK)
Hospital/treatment centre

Southwick Hill Road
Cosham
Portsmouth
PO6 3LY
England
United Kingdom

Website http://www.porthosp.nhs.uk/
ROR logo "ROR" https://ror.org/009fk3b63

Funders

Funder type

Research organisation

British Renal Society
Private sector organisation / Associations and societies (private and public)
Alternative name(s)
BRS
Location
United Kingdom

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Editorial Notes

30/08/2016: No publications found in PubMed, verifying study status with principal investigator.