None listed
Conditions
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.
Interventions
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
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.
Sponsors
The Queen Elizabeth Hospital
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver)
Eligibility
Sex/Gender
All
Age
40 Years to No maximum
Healthy volunteers
No
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.
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)
Outcome results
None listed