Omega-3 fatty acids have small analgesic effect

Clinical Question

Can long-term dosing of omega-3 fatty acids decrease inflammatory joint pain?

Bottom Line

In patients with joint pain due to rheumatoid arthritis, inflammatory bowel disease, or dysmenorrhea, continuous therapy with fish oil or other sources of omega-3 fatty acids produced statistically significant decreases in pain. The onset of action is approximately 3 months. Even though the benefit may be small, the lack of significant side effects and the beneficial effect on cardiovascular disease (Circulation 2002;106:2747-2757) make fish oil and other sources a useful option in patients with pain due to inflammation. (LOE = 1a)

Reference

Goldberg RJ, Katz J. A meta-analysis of the analgesic effects of omega-3 polyunsaturated fatty acid supplementation for inflammatory joint pain. Pain 2007;129;210-223.  [PMID:17335973]

Study Design

Meta-analysis (randomized controlled trials)

Funding

Self-funded or unfunded

Setting

Various (meta-analysis)

Synopsis

Omega-3 fatty acids may decrease inflammation by competing with arachidonic acid, the precursor to the inflammatory prostaglandins. To identify research for inclusion, the researchers searched several databases for English-language randomized clinical trials, also searching references of retrieved articles for additional relevant studies. The data were abstracted by a single person but 2 researchers independently assessed study quality. The resulting meta-analysis included 17 studies enrolling a total of 823 patients, though not all studies evaluated all outcomes. The studies used fish, seal, or flaxseed oil to provide various amounts of omega-3 fatty acid. High dose was defined as greater than 2.7 g daily. All comparisons were against inactive placebo or olive oil, which might have antiinflammatory property. Daily supplementation for 3 to 4 months reduced patient-reported joint pain intensity, minutes of morning stiffness, number of painful joints, and analgesic consumption. The benefit was not striking and was not found in physician-reported scores or the Ritchie articular index. The quality of included studies was satisfactory.