ANZCTR - Registration

The ANZCTR website will be unavailable from 1pm until 3pm (AEDT) on Wednesday the 30th of October for website maintenance. Please be sure to log out of the system in order to avoid any loss of data.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers

Trial registered on ANZCTR

Registration number

ACTRN12621000548831

Ethics application status

Approved

Date submitted

2/02/2021

Date registered

11/05/2021

Date last updated

12/04/2022

Date data sharing statement initially provided

11/05/2021

Type of registration

Retrospectively registered

Titles & IDs

Public title

The CKD Bowel Health Study

Scientific title

A mixed-method observational study of understanding the bowel health and gastrointestinal symptom management strategies in patients with chronic kidney disease (CKD)

Secondary ID [1]

Nil Known

Universal Trial Number (UTN)

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Chronic Kidney Disease

Gastro-Intestinal Intolerance

Gut microbiome

Condition category

Condition code

Renal and Urogenital

Kidney disease

Oral and Gastrointestinal

Inflammatory bowel disease

Intervention/exposure

Study type

Observational

Patient registry

False

Target follow-up duration

Target follow-up type

Description of intervention(s) / exposure

In patients with chronic kidney disease, we will observe the prevalence and risk factors of gastrointestinal intolerance before and after kidney transplantation. The duration of the observation will be anytime before transplantation, then 4, 12, and 28 weeks post-transplantation. Adults aged 18 years and older. Patients with kidney failure (CKD Stage 4 to 5D: estimated Glomerular Filtration Rate = 0 to 29 mL/min/1.73m2 and albuminuria > 300 mg/g) on dialysis listed on the deceased donor kidney transplant waiting list, or patients with kidney failure with a planned pre-emptive transplant within 12 months. This includes both kidney-only and simultaneous pancreas-kidney transplant candidates.

Three sub-studies will be undertaken as follows:

Study 1. An observational longitudinal study of the burden and risk factors of GI intolerance in kidney transplant candidates (patients with kidney failure on dialysis and are eligible for transplantation) and in kidney transplant recipients.
General patient contact information, demographic characteristics, medical history, and CKD health status will be collected via the Demographics Questionnaire.
The baseline assessments, pre-transplant of observational data will be collected via the Observational Questionnaire (Baseline): which will collect transplant status, current medications and supplements, general health via the EQ-5D Questionnaire, faecal characteristics using the Bristol Stool Chart, gastrointestinal symptoms via the Gastrointestinal Symptom Rating Scale (GSRS), quality of life using the Gastrointestinal Quality of Life Scale (GIQLS), personal management strategies of gut health and GI symptoms, dietary patterns using the Food Frequency Questionnaire (FFQ), and safety parameters and adverse events.
To repeat the instruments, the Observational Questionnaire (Follow-Up) will be repeated as the same form and administered at 4, 12, and 28 weeks post-transplant (28 weeks being the final follow-up time-points). This questionnaire contains the same instruments without the patient contact information and demographic sections. It will be administered by the study researcher face-to-face in clinic at usual visits, or completed by the patient at home where language and literacy skills are competent. The Observational Questionnaire takes approximately 30-60 minutes to complete.

Study 2. A semi-structured qualitative interview study in kidney transplant candidates and kidney transplant recipients. (A subset of the first 20 participants to agree will be selected from the Observational Study 1).
A semi-structured face-to-face interview will be conducted with each participant in their choice of either in a clinic room or via video conference. The interviews will be administered by the study research personnel who are research academics with training in qualitative research. Some participants may be known to the interviewers but only from the recruitment process. Neither interviewer will have clinically treated the participants.
The Qualitative Interview Guide includes the following sections:
Demographics
Interview 1: general perspectives and experience of gut health in CKD; perceived causes, impact and management of GI symptoms in CKD; expectations of transplantation; reasons for participating in the study;
Interview 2: experience of being in the study; experience of the transplant; experience of GI symptoms post-transplant
The guide was developed following a review of the literature and discussion among the research team consisting of nephrologists and public health (qualitative) academics. Schedule: Participants will be interviewed twice: once at baseline (anytime pre-transplant) (Visit 1) and once post-transplant at the 28-week follow-up (Visit 4). These will be approximately 30-45 minutes long.

Study 3. A discrete choice experiment of patient preferences regarding the perspectives of the different treatment and intervention strategies for the management of GI symptoms in patients with kidney transplants. All participants from study 1 will be approached to participate. (Options will be based on the outcomes of Study 2. Participant will be selected from the Observational Study 1, but also new recruits of kidney transplant recipients). At either Visit 3 or Visit 4, or anytime within 4 months post-transplant, participants will be administered the electronic Discrete Choice Experiment Survey (NGENE Software) directly after attending their usual medical appointment with their surgeon using a clinic computer. Participants will be identified by their name and participant study ID which will be linked to their baseline information. Demographics will have already been taken in Study 1. The survey will be administered as follows: (1) instructions and introduction of the study aim, (2) explanation of attributes, (3) explanation of choice sets.
In the Discrete Choice Experiment Survey, participants will be given 5 to 10 choice sets to answer their most preferred scenario of post-transplant treatment options. The anticipated survey time is approximately 5-10 minutes.
The attributes are: mode of taking supplements; average cost per month; access to supplements; dietary changes; post-transplant prescribed immunosuppressive medications.
The survey was developed following a review of the literature and discussion among the research team consisting of nephrologists and public health (qualitative) academics.

Intervention code [1]

Not applicable

Comparator / control treatment

No control group

Control group

Uncontrolled

Outcomes

Primary outcome [1]

Composite outcome: Prevalence of gastrointestinal intolerance (any severity) in patients with kidney disease before and after transplantation, collected via the Observational Questionnaire (Baseline): which will collect transplant status, current medications and supplements, faecal characteristics using the Bristol Stool Chart, gastrointestinal symptoms via the Gastrointestinal Symptom Rating Scale (GSRS), quality of life using the Gastrointestinal Quality of Life Scale (GIQLS), personal management strategies of gut health and GI symptoms, dietary patterns using the Food Frequency Questionnaire (FFQ), and safety parameters and adverse events.

Timepoint [1]

1. Observational Questionnaire (Baseline) (anytime before kidney transplant)
2. Observational Questionnaire (Follow-up) at 4 weeks post kidney transplant
3. Observational Questionnaire (Follow-up) at 12 weeks post kidney transplant
4. Observational Questionnaire (Follow-up) at 28 weeks post kidney transplant

Primary outcome [2]

Composite outcome: Change in gastrointestinal intolerance (any severity) symptom burden before and after transplantation, collected via the Observational Questionnaire (Baseline): which will collect transplant status, current medications and supplements, faecal characteristics using the Bristol Stool Chart, gastrointestinal symptoms via the Gastrointestinal Symptom Rating Scale (GSRS), quality of life using the Gastrointestinal Quality of Life Scale (GIQLS), personal management strategies of gut health and GI symptoms, dietary patterns using the Food Frequency Questionnaire (FFQ), and safety parameters and adverse events. Before and after will be assessed by comparing the questionnaires performed at baseline, 4, 12, 28 weeks post-transplant.

Timepoint [2]

Primary outcome [3]

Safety parameters and adverse events. Collected as open fields to provide the opportunity to report anything undue by the patient during this process.

Timepoint [3]

Secondary outcome [1]

Stool characteristics (Bristol Stool Chart - 7 point scale of stool varieties from constipated to diarrhoea)

Timepoint [1]

1. Anytime before kidney transplant
2. Follow-up at 4 weeks post kidney transplant
3. Follow-up at 12 weeks post kidney transplant
4. Follow-up at 28 weeks post kidney transplant

Secondary outcome [2]

Understand patients’ perspectives and attitudes towards gut health, their own beliefs about how their gut health impacts their CKD condition, and their experiences with ways to improve or maintain gut health. (Instrument: A semi-structured face-to-face interview will be conducted with each participant in their choice of either in a clinic room or via video conference)

Timepoint [2]

1. At baseline collection (anytime before kidney transplant)
2. At 28 weeks post kidney transplant follow-up collection

Secondary outcome [3]

Post-transplant preferences of treatment strategies in patients with GI intolerance. (Instrument: Discrete Choice Experiment of five attributes: mode of taking supplements; average cost per month; access to supplements; dietary changes; post-transplant prescribed immunosuppressive medications.)

Timepoint [3]

A once-off single DCE survey at anytime >4 weeks up to 28 weeks post-transplant.

Secondary outcome [4]

General health and quality of life via the EQ-5D Questionnaire

Timepoint [4]

1. Anytime before kidney transplant
2. Follow-up at 4 weeks post kidney transplant
3. Follow-up at 12 weeks post kidney transplant
4. Follow-up at 28 weeks post kidney transplant

Eligibility

Key inclusion criteria

Adults aged 18 years and older.
Patients with kidney failure (CKD Stage 4 to 5D: estimated Glomerular Filtration Rate between 0 to 29 mL/min/1.73m2 and albuminuria greater than 300 mg/g) on dialysis and/or listed on the deceased donor kidney transplant waiting list, or patients with kidney failure with a planned pre-emptive transplant within 12 months.
This includes both kidney-only and simultaneous pancreas-kidney transplant candidates.

Minimum age

18 Years

Maximum age

No limit

Sex

Both males and females

Can healthy volunteers participate?

Key exclusion criteria

Prior bowel resection.
Chronic pancreatic insufficiency history of inflammatory bowel disease.
Recent infection-related diarrhoea.
Unable to give informed consent.

Study design

Purpose

Natural history

Duration

Longitudinal

Selection

Defined population

Timing

Prospective

Statistical methods / analysis

Study 1
a. Descriptive analysis of the prevalence and management strategies of GI intolerance in patients with kidney failure and have a kidney transplant.
b. Baseline characteristics and dietary patterns will be compared between recipients with and without GI intolerance using chi-square (to compare categorical variables), analysis of variance (compare means for normally-distributed variables) and Kruskal-Wallis tests (to compare medians for non-normally-distributed variables).
c. Longitudinal mixed models with random intercepts will be conducted to assess the relationship between dietary patterns and GI intolerance, accounting for confounders including age, sex, medication use, and CKD stage.
d. Sample size: this is a longitudinal study of the effects of diet and/or medication use and/or management strategies on GI symptoms before and after kidney transplant. The sample size of 100 participants to complete the study has been determined as adequate to have the power to test the primary outcomes of prevalence of GI symptoms estimated at 11% in the CKD population (Hill, et al., 2016).

Study 2
a. Interviews will be recorded with the participant consent and transcribed verbatim. Transcript will be analysed using HyperRESEARCH V.3.7.3 software (Researchware, Inc., 2020). Field notes will also be taken.
b. Thematic analysis will be used to independently code all transcripts and notes line by line by two study personnel to identify concepts. Following the thematic analysis (of two interviews per participant) we will convene a discussion group with all patients who had participated to discuss the preliminary themes and findings to ascertain whether they appropriately reflect the perspectives of the CKD patients. This will be via Zoom and for practical technology purposes we will split into two groups of 15.

Study 3
a. We will use “NLOGIT, version 5.0 (Econometric Software, Castle Hill, NSW, Australia; www.limdep.com/products/ nlogit/) to analyse the data. Internal validity (that is, the extent to which results were consistent with the researchers’ prior expectations) will be assessed by examining the signs and significance of parameter estimates."
b. Sample size: for the Discrete Choice Experiment Survey we used the electronic software NGENE (NGENE Software, 2020) to ascertain the required sample size of 62 participants to
account for 5 randomisation blocks of 5 attributes.

Recruitment

Recruitment status

Recruiting

Date of first participant enrolment

Anticipated

Actual

1/04/2021

Date of last participant enrolment

Anticipated

30/11/2022

Actual

Date of last data collection

Anticipated

28/02/2023

Actual

Sample size

Target

170

Accrual to date

140

Final

Recruitment in Australia

Recruitment state(s)

NSW,WA

Recruitment hospital [1]

Westmead Hospital - Westmead

Recruitment hospital [2]

Sir Charles Gairdner Hospital - Nedlands

Recruitment postcode(s) [1]

2145 - Westmead

Recruitment postcode(s) [2]

6009 - Nedlands

Recruitment postcode(s) [3]

2145 - Wentworthville

Recruitment postcode(s) [4]

6009 - Broadway Nedlands

Funding & Sponsors

Funding source category [1]

Government body

Name [1]

NHMRC

Address [1]

National Health and Medical Research Council
GPO Box 1421
Canberra ACT 2601

Country [1]

Australia

Primary sponsor type

Individual

Name

Prof Germaine Wong

Address

Renal Ward
Westmead Hospital
Hawkesbury Rd, Westmead NSW 2145

Country

Australia

Secondary sponsor category [1]

None

Name [1]

Address [1]

Country [1]

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

Western Sydney Local Health District

Ethics committee address [1]

Westmead Hospital
Hawkesbury Road Westmead NSW 2145

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

10/11/2020

Approval date [1]

18/01/2021

Ethics approval number [1]

2020/ETH03007

Summary

Brief summary

This study aims define the burden of GI intolerance in patients with kidney failure on dialysis and with kidney transplants, and to understand patients’ experiences of GI intolerance and their perspectives on the management strategies of these symptoms. 

The hypotheses: 
1. GI intolerance is common in patients with kidney failure (transplant candidates) and kidney transplants.
2. Kidney transplant candidates and recipients have different experiences and perspectives of GI symptoms and intolerance.
3. Kidney transplant candidates and recipients have diverse views on the treatment preferences of GI intolerance.

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

Prof Germaine Wong

Address

Renal Transplant Unit
Westmead Hospital
Hawkesbury Road, Westmead NSW 2145

Country

Australia

Phone

+61 411603282

Fax

[email protected]

Contact person for public queries

Name

Tess Cooper

Address

Centre for Kidney Research
Children's Hospital at Westmead
Hawkesbury Road, Westmead NSW 2145

Country

Australia

Phone

+61 426483629

Fax

[email protected]

Contact person for scientific queries

Name

Tess Cooper

Address

Centre for Kidney Research
Children's Hospital at Westmead
Hawkesbury Road, Westmead NSW 2145

Country

Australia

Phone

+61 426483629

Fax

[email protected]

Data sharing statement

Will individual participant data (IPD) for this trial be available (including data dictionaries)?

No/undecided IPD sharing reason/comment

No consent for IPD data to be made available for sharing will be sought from the participants.

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

Source	Title	Year of Publication	DOI
Embase	The CKD bowel health study: understanding the bowel health and gastrointestinal symptom management in patients with chronic kidney disease: a mixed-methods observational longitudinal study (protocol).	2021	https://dx.doi.org/10.1186/s12882-021-02600-x
Embase	Patient Preferences for the Management of Gastrointestinal Symptoms in Kidney Transplantation: a Discrete Choice Experiment.	2023	https://dx.doi.org/10.1016/j.ekir.2023.07.034

N.B. These documents automatically identified may not have been verified by the study sponsor.

Trial Review

Documents added manually

Documents added automatically