ASK DIS: Supplementation in Osteoarthritis

role of diet or dietary supplements in the treatment of osteoarthritis (OA) remains unclear.
Research into diet as an independent factor has focused on antioxidants (eg, vitamins C and E) and on vitamin D.
use of glucosamine and chondroitin for osteoarthritis (OA) has been controversial, and these widely used remedies are of uncertain benefit; results of randomized trials have varied

Chondroitin and Glucosamine

Glucosamine typically been studied at a dose of 500 mg three times daily, and chondroitin at a dose of 400 mg three times daily.
Glucosamine should not be administered to patients who are allergic to shellfish.
The balance of evidence from high-quality trials has shown little to no evidence of clinically meaningful benefit

Evidence

A 2015 Cochrane review of 43 randomized trials including 9110 patients with mostly knee OA found that chondroitin, either alone or in combination with glucosamine, resulted in a statistically significant improvement in pain scores in studies with <six months of follow-up.

Although the benefit was considered clinically meaningful, the effect was small, with an 8-point greater improvement of pain (range 0 to 100) from mostly low-quality trials

In a multicenter randomized non-inferiority trial, 606 patients with severe pain from knee OA were treated with either the combination of chondroitin sulfate and glucosamine or celecoxib. At six months follow-up, there were no significant differences between the two groups in reduction in pain, stiffness, functional limitation, and joint swelling.

However, important limitations of the study design include the lack of a placebo arm as well as the preparation of the chondroitin and glucosamine, which may not be generalized to other compound mixtures

Vitamin C

analyzed data strongly suggested a relationship between vitamin C intake and progression of OA; the risk of progression was reduced threefold in patients with mean vitamin C intakes above 152 mg per day.

Vitamin E and Beta Carotene

may also reduce the risk of progression, but the data on these nutrients were less consistent.
In comparison, intake of these three nutrients did not affect the rate of development of OA
In contrast to the observational data, the administration of vitamin E (500 international units per day) for six months did not provide pain relief or prevent radiographic progression

Vitamin D

risk of OA progression increased threefold in patients with low vitamin D intake
Other observational data have also suggested an association with pain and radiographic
low intake and serum levels of vitamin D did not increase the risk for developing OA in the Framingham follow-up analysis
several randomized trials of vitamin D treatment have found no benefit from this approach, although one trial reported a small degree of symptomatic improvement

Recommendations

Not routinely recommend to use glucosamine and chondroitin for OA these medications, but there appear to be few risks associated with their use.
In patients who use these medications we advise their discontinuation if significant relief is not achieved after a six-month trial
Supplementation with these agents for the treatment of OA is not suggested; randomized trials have failed to confirm that dietary supplementation with such agents can provide the potential benefits suggested by data from observational studies

References

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