Are you one of the over 30 million Americans suffering from osteoarthritis?
Or maybe you know someone who is?
Do you or someone you know take a lot of over-the-counter supplements for a variety of reasons?
If so, read on to find out more about what OA is, some common treatments, and a recently published study about vitamin D and fish oil use in chronic knee pain.
What Is Osteoarthritis?
“Osteo” means bone, and “arthritis” means inflammation of the joints.
There are many conditions involving arthritis, but osteoarthritis is the most common form of arthritis.
Osteoarthritis (OA) is a degenerative joint disease, sometimes referred to as “wear and tear”. The cartilage around joints breakdown over time, causing inflammation, swelling, pain, and stiffness.
Who Is Most Affected?
Over 32.5 million Americans are affected by OA, and some common risk factors include:
- Being overweight
- Older age
- Female gender
- Joint injury or overuse
- Family members with OA
How Is OA Diagnosed and Treated?
A doctor diagnoses OA through talking to a patient about their history of symptoms, doing a physical exam to look at the joints, and performing tests such as x-rays and lab work.
While primary care doctors can diagnose and manage OA, sometimes a specialist called a “rheumatologist” is included in the care team.
The main treatments for OA include:
Lifestyle changes: Mainly, losing weightand exercising.
- Losing weight can relieve some of the pressure on joints
- Especially weight-bearing joints such as the hips and knees, which are typically the most affected.
- Exercising can not only help patients lose weight, but it is also helpful in maintaining a good range of motion.
- It is recommended to work up to 150 minutes of moderate, low impact (walking, swimming/water aerobics, biking) exercising per week.
- Individuals can work with their healthcare team (including a physical therapist!) to set goals and develop a plan for accountability.
- 150 mins may seem like a lot, but every minute counts and something is better than nothing.
Surgery: Not everyone is a candidate for surgery. But for those who are, surgery can be useful in OA and often involves problematic joint replacement – usually hips and knees. Surgery is usually reserved for when other therapies have failed, and the disease has progressed to be more severe.
There is usually a lot of discussion and planning with the healthcare team to discuss each patient’s unique pros and cons concerning the decision to go ahead with surgery.
Medications: For pain and inflammation, many people diagnosed with OA are advised to start with oral and topical over-the-counter pain medications, and will sometimes require prescription medications.
- Sometimes patients can also receive injections from the doctor directly into the joint.
- One more group of products commonly used for OA are dietary supplements. Evidence is mixed depending on the supplement, dose, duration of use, etc. When it comes to supplements, it is important to keep in mind 1) how they are handled by the FDA and get to market, and 2) the need to discuss with your healthcare team before starting a supplement (as they are not without risks).
Shedding Some Light on Dietary Supplements
As mentioned above, there is mixed evidence regarding dietary supplements in general, and those for OA are no exception.
This is partially due to the fact that extensive, robust clinical trials are not necessary before getting an OTC product to market like other FDA-approved medications.
Some examples of dietary supplements that have been used in OA include: glucosamine with chondroitin, herbal supplements, collagen-containing products, and vitamins (vitamin D and E).
More evidence comes out each year to inform healthcare professionals and patients what works and what doesn’t work in addressing diseases like OA.
A New Study to Add to the Growing List
One of the more recent studies to published on supplement use in OA was a subgroup of individuals in the VITamin D and OmegA?3 TriaL (VITAL) trial.
The VITAL trial was a randomized, double-blind, placebo-controlled trial of over 25,000 individuals.
VITAL researchers wanted to look at vitamin D due to its potential for bone resorption and anti-inflammatory properties, and marine omega-3 fatty acids (aka “fish oil”) for its anti-inflammatory properties, and their potential in benefit and role in knee pain.
This subgroup analysis published in late June 2020 in Arthritis and Rheumatology included about 1,400 people who suffered from chronic knee pain.
Patients were randomized to take either 1) vitamin D or placebo, and 2) marine omega-3 fatty acids (aka “fish oil”) or placebo, meaning there were four possible combinations of medications.
The average age of the participants was 67.7 years, and 66% were female. Each person’s pain was measured at the beginning (baseline) and every year after that for an average follow-up time of 5.3 years.
Pain was assessed using a questionnaire called the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is scored 0?100, 100 being the worst pain. Researchers analyzed these scores over time and found no statistical difference in the pain score between the treatment groups.
What Does This Mean?
This study certainly adds to the body of evidence surrounding supplement use in OA. It is good to see both positive and negative findings being published so that consumers can be well informed.
This analysis only looked at the supplement’s potential effect on chronic knee pain. These supplements certainly have other uses that are more evidence-based, so patients may have other reasons to be taking them.
Ultimately, the same approach to care remains:
- When it comes to evidence-based healthcare, no single study by itself should tell you what to do or not do. It’s important to look at multiple, well-done studies and/or reputable resources when making decisions about your care.
- Always talk to your healthcare team before starting or stopping any medication, including supplements. Each patient has unique pros and cons to consider, and they know you the best. Supplements are not without risks; they can interact with some of your current medications. Even with mixed evidence, sometimes it’s ok to give something a try, but again, talk with your team.
References, Studies and Sources:
- Osteoarthritis. MedlinePlus. Updated July 15, 2020. Accessed September 18, 2020. https://medlineplus.gov/osteoarthritis.html#cat_78
- MacFarlane LA, Cook NR, Kim E, et al. The Effects of Vitamin D and Marine Omega?3 Fatty Acid Supplementation on Chronic Knee Pain in Older U.S. Adults: Results from a Randomized Trial. Arthritis & Rheumatology. June 25, 2020. Accessed September 18, 2020. https://doi.org/10.1002/art.41416
- Rheumatology Network Editorial Staff. Vitamin D and Fish Oil Fail Osteoarthritis Trial. Rheumatology Network. June 25, 2020. Accessed September 18, 2020. https://www.rheumatologynetwork.com/view/vitamin-d-and-fish-oil-fail-osteoarthritis-trial
- Information for Consumers on Using Dietary Supplements. U.S. Food & Drug Administration. Updated August 16, 2020. Accessed September 18, 2020. https://www.fda.gov/food/dietary-supplements/information-consumers-using-dietary-supplements
- Osteoarthritis (OA). Centers for Disease Control and Prevention. Updated July 27, 2020. Accessed September 18, 2020. https://www.cdc.gov/arthritis/basics/osteoarthritis.htm

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