Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619001270101
Ethics application status
Approved
Date submitted
9/08/2019
Date registered
12/09/2019
Date last updated
12/09/2019
Date data sharing statement initially provided
12/09/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Comparison of dietary oils in osteoarthritis patients: a feasibility study
Scientific title
A randomised, controlled trial to assess the feasibility of consuming three dietary oils over 3 months amongst osteoarthritis patients
Secondary ID [1] 298686 0
None
Universal Trial Number (UTN)
Trial acronym
DOT
Linked study record
None

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 313584 0
Condition category
Condition code
Musculoskeletal 312020 312020 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will be randomly assigned to one of three groups in this study:
Group 1: fish oil capsule group (control group)
Group 2: canola oil group
Group 3: light olive oil group

Group 1 will receive fish oil capsules (Nature's Way 1500 mg), and will be required to take 1 capsule per day, providing 0.45 g EPA and DHA.
Group 2 will receive canola oil in an opaque bottle. They will be asked to consume 1 Tbsp per day, providing approximately 12 g 18:1 c-9 oleic acid, and trace amounts of long chain polyunsaturated fatty acids.
Group 3 will receive light olive oil (Moro brand) and will be required to consume 1 Tbsp per day, providing approximately 16 g c-9 oleic acid, trace long chain polyunsaturated fatty acids.

The liquid oils will be decanted into opaque bottles and sealed under nitrogen, and labelled with a generic study label, with instructions to store the oil in a cool dry place. Participants will not be told which oil group they have been allocated to. They will be told to have the oils as an adjunct to their normal diets, and to consume the oils in any way that suits them (e.g. alone or mixed into food).

All three groups will be instructed to maintain their diet, physical activity and other routines for the duration of the study.

Participants will return any left over capsules or oil at the study end, to determine compliance with the recommendations.

The study is being conducted by a dietitian who will provide the instructions and be available to discuss any issues for the duration of the study.

Participants will be screened over the phone, to obtain demographic information and determine eligibility. If eligible, they will be invited to a baseline visit. They will be randomised in the interim. At baseline, anthropometric measures, a fasting blood sample for lipids, erythrocyte fatty acids and a full blood exam, and a pain score via visual analogue scale will be obtained. The oil will be provided to participants at this visit. Before commencing their allocated oil, participants will complete a 4-day weighed food dairy at home to assess their baseline dietary intake. This will be done during the first week of the study. Once they have completed their baseilne food diary, it will be returned via reply-paid envelope.

At week 9, they will complete a second 4-day weighed food diary to determine any changes in their diet since commencing the oil. This will be accompanied by a safety phone call.

At week 13, all participants will return to the clinic to repeat the anthropometric measures and return their oils or capsules. A second blood sample will determine changes in any blood biochemistry. A feasibility questionnaire will assess participants' experiences taking the oils, and whether they could tell which oil they were consuming. Following their final visit, all participants will be invited to attend a focus group, which will take place 1-2 months after they finished the study, to discuss issues surrounding taking oils as a adjunct dietary supplement.

All visits will take place at the Rheumatology Unit, Ward 5C, The Queen Elizabeth Hospital.
Intervention code [1] 315249 0
Treatment: Other
Comparator / control treatment
Group 1, receiving fish oil capsules, will act as the control group
Control group
Active

Outcomes
Primary outcome [1] 321007 0
To determine the palatability of consuming 1 tablespoon of high monounsaturated liquid oil daily as an adjunct diet therapy among osteoarthritis patients. Palatability will be assessed using a short feasibility questionnaire administered at week 13, with likert-scale questions and open-ended questions.
Timepoint [1] 321007 0
13 weeks post-baseline visit
Primary outcome [2] 321008 0
To determine the success of blinding canola oil and light olive oil among osteoarthritis patients, This will be assessed by asking participants 'what type of oil do you think you were taking?'. If 40-60% correctly identify the oil, blinding will be considered a success.
Timepoint [2] 321008 0
13 weeks post-baseline visit
Secondary outcome [1] 373679 0
To determine the impact of 1x1500 mg fish oil capsule, 1 tablespoon of light olive oil and 1 tablespoon canola oil daily on BMI among osteoarthritis patients. Weight will be measured using digital scales in the fasted state at baseline and week 13. Height will be measured by wall-mounted stadiometre without shoes, at baseline and week 13. BMI is calculated as weight divided by height in metres squared.
Timepoint [1] 373679 0
13 weeks post-baseline visit
Secondary outcome [2] 373680 0
To determine the impact of 1x1500 mg fish oil capsules, 1 tablespoon of light olive oil and 1 tablespoon of canola oil daily on waist circumference among osteoarthritis patients. Waist circumference will be assessed using a steel luftkin 2mm measuring tape at the visual narrow or half-way between the lowest rib and top of the iliac crest, according to ISAK standards.
Timepoint [2] 373680 0
13 weeks post-baseline visit
Secondary outcome [3] 373681 0
To determine the impact of 1x1500 mg fish oil capsules, 1 tablespoon of light olive oil and 1 tablespoon of canola oil daily on erythrocyte fatty acids among osteoarthritis patients. This will be assessed using transesterification.
Timepoint [3] 373681 0
13 weeks post-baseline visit
Secondary outcome [4] 373682 0
To determine the impact of 1x1500 mg fish oil capsules, 1 tablespoon of light olive oil and 1 tablespoon of canola oil on dietary intake among osteoarthritis patients. This will be assessed by comparing the energy, macro- and micronutrient intakes from baseline, with those at week 9, measured by 4-day weighed food records.
Timepoint [4] 373682 0
9 weeks post-baseline visit
Secondary outcome [5] 373683 0
To determine the impact of 1x1500 mg fish oil capsules, 1 tablespoon of light olive oil and 1 tablespoon of canola oil daily on visual analogue pain score among osteoarthritis patients
Timepoint [5] 373683 0
13 weeks post baseline visit
Secondary outcome [6] 374801 0
To determine the impact of 1x1500 mg fish oil capsules, 1 tablespoon light olive oil and 1 tablespoon canola oil daily on fasting lipids among osteoarthritis patients. Fasting lipids will be assessed by assay, including total cholesterol, LDL and HDL cholesterol, triglycerides and total cholesterol:HDL ratio. This is a composite secondary outcome.
Timepoint [6] 374801 0
13 weeks post baseline visit

Eligibility
Key inclusion criteria
• Clinical hand or knee OA (diagnosed by a medical professional)
• 40 years of age or above
• Able and willing to consume up to 18 ml of high monounsaturated liquid oil per day for 12 weeks (olive oil and canola oil), or to consume 1x1500 mg fish oil capsule daily for 12 weeks
• Able to commit to study for 3 months, including not altering diet or physical activity levels.
• English literate, for the purpose of questionnaire completion and protocol comprehension
• Body mass index (BMI) greater than 35 kg/m2. Because there is a small risk of weight gain anyone with a BMI over 35 will be excluded.
Minimum age
40 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• Allergy to seafood
• Allergy or intolerance to olive oil and canola oil
• On waiting list for total knee replacement/major hand surgery
• Other major medical treatment or planned surgery in the next 3 months
• Known cardiovascular disease, cognitive disease, kidney or liver disease, cancer diagnosis within the last 6 months
• When not managed with medications: type 2 diabetes (fasting blood glucose greater than or equal to 7.0 mmol/L or greater than 11.0 mmol/L non-fasting, and HbA1c greater than or equal to 6.5%), hypertension (BP >139 SBP or >89 DBP) or hypercholesterolemia (total cholesterol >5.5 mmol/L)
• Otherwise medically unfit, at investigator discretion
• BMI of 36 kg/m2 or greater
• Taking anticoagulants (e.g. warfarin etc)

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)
The light olive oil and canola oils will be decanted and sealed in opaque bottles by an investigator not involved directly with participants. The bottles will be labelled with a study label, with simple instructions to take 1 Tbsp per day, and to store the oil in a cool, dry place.

The control group will not be told which oils are capsulated and which are liquid, There capsules will be provided in plain white bottles with a study label with simple instructions to take 1 capsule per day, and to store in a cool, dry place.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation will be done by simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s

Intervention assignment
Parallel
Other design features
The group receiving fish oil capsules will not be told which oils are encapsulated and which are liquid, in an attempt to blind them to which group they are in. The investigators directly involved with participants will also be blinded to allocation, except for the control group where the difference between the oil types will be obvious, due to two being liquid and one being capsules.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Baseline characteristics between groups will be analysed by unpaired t-test. Descriptive statistics (mean+/- SD or count (%)) will be presented for continuous and categorical variables as appropriate. Residual normality will be assessed, and for normally distributed variables, a linear mixed effects model will be used to compare pre- and post-VAS pain scores, lipids, erythrocyte fatty acids, full blood exam results, blood pressure, BMI and waist circumference, and dietary intake of macronutrients (total and subtypes for fatty acids, carbohydrate and sugar, protein) and total energy intake. Non-parametric equivalent tests will be used for non-normally distributed variables. Feasibility will be assessed descriptive statistics and the focus group results by qualitative methods.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
30/09/2019
Actual
Date of last participant enrolment
Anticipated
31/10/2019
Actual
Date of last data collection
Anticipated
27/01/2020
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA
Recruitment hospital [1] 14501 0
The Queen Elizabeth Hospital - Woodville
Recruitment postcode(s) [1] 27513 0
5011 - Woodville

Funding & Sponsors
Funding source category [1] 303237 0
Charities/Societies/Foundations
Name [1] 303237 0
Arthritis Foundation of Australia
Country [1] 303237 0
Australia
Primary sponsor type
Hospital
Name
The Queen Elizabeth Hospital
Address
Rheumatology Unit, Ward 5C
28 Woodville Rd
Woodville South 5011 SA
Country
Australia
Secondary sponsor category [1] 303243 0
University
Name [1] 303243 0
The University of South Australia
Address [1] 303243 0
City East Campus
Crn Nrth Tce and Frome Rd
Adelaide 5001 SA
Country [1] 303243 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303782 0
Central Adelaide Local Health Network Human Research Ethics Committee
Ethics committee address [1] 303782 0
CALHN HREC
Royal Adelaide Hospital
Port Rd
Adelaide 5000 SA
Ethics committee country [1] 303782 0
Australia
Date submitted for ethics approval [1] 303782 0
14/01/2019
Approval date [1] 303782 0
18/04/2019
Ethics approval number [1] 303782 0
HREC/19/CALHN/32

Summary
Brief summary
Osteoarthritis is a debilitating condition affecting 9% of Australians, and this is likely to increase as our population ages. There are currently no drug treatments for prevention or cure of osteoarthritis, only temporary solutions to treat pain and symptoms. Osteoarthritis can have a huge impact on quality of life and can lead to other complications, like cardiovascular disease. Looking for prevention and treatment options is therefore very important, and dietary oils might provide one potential treatment option.
Some research has investigated dietary oils and osteoarthritis. There is some evidence that certain types of oil might have some benefit, but we need to conduct more trials to find out. One of the problems with dietary oils studies is that they are difficult to blind. Blinding means that the participants in the study don’t know which treatment they are receiving, and neither do the researchers. Blinded studies are very useful, because when the treatment is kept secret, any results that are found are more likely to be because of the treatment, and not because of researcher bias or participant belief (placebo effect).
We are not sure whether it is possible to blind a dietary oils trial, how participants will handle taking different types of oils, and what impact this might have on their diets, symptoms of arthritis and other health markers like weight and cholesterol. We’d like to answer these questions, to help design a large, blinded, dietary oils study in the future.
This study has a couple of main purposes. We want to know:
• if people will be able to identify dietary oils, without being told what they are
• how people go about consuming the dietary oils (for example, alone, or with food)
• whether dietary intake of other foods and oils will be affected
• whether consuming different types of dietary oils will impact on symptoms of arthritis, such as pain, and other health markers such as weight and cholesterol levels

We will give patients with osteoarthritis three different types of dietary oils for 3 months, and assess how they take the oils, whether they can tell what the type of oil is, whether their diets change, and measure some health markers like lipids and weight. We will also look at pain scores from their arthritis to see if the dietary oils have any therapeutic effect on pain.
Trial website
NA
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 94786 0
Dr Courtney Davis
Address 94786 0
Rheumatology Unit, Ward 5C
The Queen Elizabeth Hospital
28 Woodville Rd
Woodville South, 5011 SA
Country 94786 0
Australia
Phone 94786 0
+61 882227369
Fax 94786 0
+6188134030
Email 94786 0
[email protected]
Contact person for public queries
Name 94787 0
Dr Courtney Davis
Address 94787 0
Rheumatology Unit, Ward 5C
The Queen Elizabeth Hospital
28 Woodville Rd
Woodville South, 5011 SA
Country 94787 0
Australia
Phone 94787 0
+61 882227369
Fax 94787 0
+6188134030
Email 94787 0
[email protected]
Contact person for scientific queries
Name 94788 0
Dr Courtney Davis
Address 94788 0
Rheumatology Unit, Ward 5C
The Queen Elizabeth Hospital
28 Woodville Rd
Woodville South, 5011 SA
Country 94788 0
Australia
Phone 94788 0
+61 882227369
Fax 94788 0
+6188134030
Email 94788 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
As this is a small feasibility trial, the data will be used to inform a larger trial in future. The data from the feasibility trial will therefore not be useful to the wider public.


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.