Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000516482p
Ethics application status
Submitted, not yet approved
Date submitted
9/05/2025
Date registered
23/05/2025
Date last updated
23/05/2025
Date data sharing statement initially provided
23/05/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Weight loss for chronic low back pain: a clinical trial
Scientific title
Effects of a very low energy weight loss diet on pain and disability in people with chronic low back pain and overweight or obesity compared to healthy eating advice control: a randomised controlled trial protocol
Secondary ID [1] 314100 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Chronic low back pain 336879 0
Overweight 337502 0
Obesity 337599 0
Condition category
Condition code
Musculoskeletal 333353 333353 0 0
Other muscular and skeletal disorders
Diet and Nutrition 333354 333354 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants in this group be offered a ketogenic Very Low Energy Diet (VLED) weight loss program prescribed by a dietitian. Participants will receive 6 individual consultations with the dietitian (over 6 months) via videocall (Zoom). The first consultation will be approximately 45 minutes in duration, with follow-up consultations approximately 30 minutes. Consultations will be recommended to occur in weeks 1, 3, 6, 10, between weeks 14-17, and between weeks 19-23. During consultations, appropriate weight loss goals will be agreed and a tailored management plan for losing weight developed. Conversations based on motivational interviewing principles and techniques will be used to develop readiness to change (motivation) and confidence to self-manage.

The VLED comprises two phases: 1) intensive weight loss using meal replacements, and 2) transition off meal replacements onto a longer-term eating plan for weight maintenance.

The intensive weight loss phase involves replacing two meals with VLED meal replacement products. The third meal of the day comprises protein, non-starchy vegetables/salad, and a small amount of fat/oil. In total, the diet contains 800 calories (3,280 kilojoules).

Phase 2 will commence once participants reach their individual goal weight. To transition, only one meal replacement is used per day and foods containing carbohydrates are reintroduced. After approximately four weeks of one meal replacement per day, the participant will commence a healthy eating diet which is consistent with the principles of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) total wellbeing diet (i.e. high protein, low glycaemic index carbohydrate, low fat).

Participants will also be provided with additional bespoke educational and behaviour change resources (booklets specifically designed for this trial) to support their weight loss efforts.
Intervention code [1] 330673 0
Lifestyle
Intervention code [2] 330674 0
Behaviour
Comparator / control treatment
Participants will receive general healthy eating advice, consistent with the Australian National Dietary Guidelines, delivered by a dietitian via one Zoom consultation (approximately 45 minutes in duration). Dietitians will use the resources and information provided on the Australian Guide to Health Eating website to educate participants about healthy eating.
Control group
Active

Outcomes
Primary outcome [1] 340930 0
Low back pain intensity over the past week
Timepoint [1] 340930 0
Baseline, 6 (primary timepoint), and 12-months post-randomisation
Primary outcome [2] 340931 0
Low back pain-related disability
Timepoint [2] 340931 0
Baseline, 6 (primary timepoint), and 12-months post-randomisation
Secondary outcome [1] 445499 0
Body weight
Timepoint [1] 445499 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [2] 445500 0
Body mass index
Timepoint [2] 445500 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [3] 445501 0
Total body fat mass
Timepoint [3] 445501 0
Baseline and 6-months post-randomisation
Secondary outcome [4] 445502 0
Visceral fat mass
Timepoint [4] 445502 0
Baseline and 6-months post-randomisation
Secondary outcome [5] 445503 0
Work productivity
Timepoint [5] 445503 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [6] 445504 0
Work absenteeism
Timepoint [6] 445504 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [7] 445505 0
Sleep quality
Timepoint [7] 445505 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [8] 445506 0
Depression
Timepoint [8] 445506 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [9] 445507 0
Health-related quality of life
Timepoint [9] 445507 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [10] 445508 0
Pain-related fear of movement
Timepoint [10] 445508 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [11] 445509 0
Pain self-efficacy
Timepoint [11] 445509 0
Baseline, 6-, and 12-months post-randomisation
Secondary outcome [12] 445510 0
Global rating of overall change in low back pain problem
Timepoint [12] 445510 0
Baseline, 6-, and 12-months post-randomisation

Eligibility
Key inclusion criteria
Participants will be eligible for the trial if they meet the following inclusion criteria:
i) Have chronic low back pain, defined as pain in the area between the 12th rib and buttock crease with or without accompanying leg pain;
ii) Low back pain of at least 12 weeks duration;
iii) Mean back pain intensity >= 4/10 on NRS in the past week;
iv) Sufficient fluency in the English language to understand and respond to English language questionnaires and to engage with the interventions;
v) Age 18-70, inclusive;
vi) Access to a device with internet connection;
vii) Self-reported BMI >27 kg/m^2; based on the Royal Australian College of General Practitioners guidelines for obesity management which indicates usage of a very low energy diet to induce rapid weight loss for those with BMI >27 kg/m^2 and comorbidities;
viii) Willing to lose weight and use meal replacements;
ix) Willing and able to give informed consent and participate in the assessment procedures.
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
i) Known or suspected serious pathology causing CLBP (e.g. spinal fracture, cancer, cauda equina compression, inflammatory arthritis);
ii) Spinal surgery less than 12 months previously;
iii) On waiting list for/planning back/lower limb surgery or bariatric surgery in next 12 months;
iv) Weight loss of > 2 kg over the previous 3 months;
v) Using, or planning to use, weight loss drugs (e.g., GLP-1 receptor agonists, such as Semaglutide);
vi) Unable to undertake ketogenic very low energy diet (VLED) without closer medical supervision, including self-reported:
a. Type 1 diabetes
b. Type 2 diabetes requiring medication apart from metformin
c. stroke or cardiac event in previous 6 months
d. unstable cardiovascular condition
e. fluid intake restriction
f. renal (kidney) problems (unless clearance is obtained from general practitioner, including general practitioner confirmation that estimated glomerular filtration rate >30 mL/min/1.73m^2)
vii) Pregnancy or planned pregnancy in next 12 months, or less than 6-months postpartum or breastfeeding;
viii) Vegan dietary requirements due to complexity of delivering a nutritionally complete diet within the ketogenic diet regime.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation will be concealed via central randomisation; the randomisation schedule will be computer-generated and prepared by an independent biostatistician. The schedule will be stored on a password-protected website (REDCap) at The University of Melbourne maintained by a researcher not involved in either participant recruitment or administration of primary/secondary outcome measures.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation schedule will be prepared by the biostatistician using randomly permuted block of varying sizes, stratified by dietitian and BMI (27 to less than 35 kg/m^2, and greater than or equal to 35 kg/m^2).
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
26/01/2026
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
198
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW,QLD,VIC

Funding & Sponsors
Funding source category [1] 318607 0
University
Name [1] 318607 0
The University of Melbourne
Country [1] 318607 0
Australia
Primary sponsor type
University
Name
The University of Melbourne
Address
Country
Australia
Secondary sponsor category [1] 321011 0
None
Name [1] 321011 0
Address [1] 321011 0
Country [1] 321011 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 317210 0
University of Melbourne Central Human Research Ethics Committee
Ethics committee address [1] 317210 0
Ethics committee country [1] 317210 0
Australia
Date submitted for ethics approval [1] 317210 0
19/03/2025
Approval date [1] 317210 0
Ethics approval number [1] 317210 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 140354 0
Dr Belinda Lawford
Address 140354 0
161 Barry St, The University of Melbourne, VIC 3010
Country 140354 0
Australia
Phone 140354 0
+61 03 8344 2045
Fax 140354 0
Email 140354 0
[email protected]
Contact person for public queries
Name 140355 0
Belinda Lawford
Address 140355 0
161 Barry St, The University of Melbourne, VIC 3010
Country 140355 0
Australia
Phone 140355 0
+61 03 8344 2045
Fax 140355 0
Email 140355 0
[email protected]
Contact person for scientific queries
Name 140356 0
Belinda Lawford
Address 140356 0
161 Barry St, The University of Melbourne, VIC 3010
Country 140356 0
Australia
Phone 140356 0
+61 03 8344 2045
Fax 140356 0
Email 140356 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
Yes
Will there be any conditions when requesting access to individual participant data?
Persons/groups eligible to request access:
• Researchers
Conditions for requesting access:
• Yes, conditions apply:
• Requires a scientifically sound proposal or protocol
• Requires a data sharing agreement between data requester and trial custodian or sponsor
What individual participant data might be shared?
• All de-identified individual participant data
What types of analyses could be done with individual participant data?
• Any type of analysis (i.e. no restrictions on data re-use)
When can requests for individual participant data be made (start and end dates)?
From:
After publication of main results
To:
No end date
Where can requests to access individual participant data be made, or data be obtained directly?
• Email of trial custodian, sponsor or committee: Dr Belinda Lawford [email protected]

Are there extra considerations when requesting access to individual participant data?
No


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
No additional documents have been identified.