Many of these therapies have a long history of apparent safety and efficacy but have not been adequately tested in controlled trials. The article reviews the most frequently used products and practices.
GLUCOSAMINE AND CHONDROITIN
Two of the complex building blocks of normal connective tissue, GLUCOSAMINE sulfate and Chondroitin sulfate have been used for osteoarthritis relief for decades in Europe.
GLUCOSAMINE, a constituent of glycoproteins, proteoglycans, and glycosaminoglycans, is known to reduce osteoarthritis cartilage. It may also have anti-inflammatory effects. Most of the studies suggest benefit in terms of pain relief. The magnitude of improvements was comparable to that obtained with NSAIDs. Radiographic follow-up suggests a slowing of osteoarthritis progression.
Chondroitin sulfate is available in over-the-counter formulations. Trials have shown positive trends for analgesic effects in patients with osteoarthritis of the knee and hip. Longer-term studies are needed to clarify its place in the clinical armamentarium.
Early literature links certain foods to arthritis flares. Medical history is rich with description of how foods or drinks contribute to the onset and perpetuation of gout.
Fasting appears to have a beneficial effect on pain, stiffness, inflammation. The mechanism is obscure but could be related to reduced immunologic activity that comes from decreased food intake.
Benefits may also be derived from fish oil, fish oil fatty acid derivatives, and certain plant oil supplements. Eicosapentaenoic acid and decosahexaenoic acid preparations from cold-water fish are widely available in capsule form. Plant oils from borage (Borage officinalis), evening primrose (Oenothera biennia), and flaxseed (Linus usitatissimum) may provide similar benefits. The optimal use of these agents remains to be defined.
Studies suggest that those with the lowest intake and serum levels of 25-hydroxyvitamin Do were three times more likely than those with highest intake and serum levels of the vitamin to experience progression of their disease.
High vitamin C intake was also associated with a threefold reduction in osteoarthritis progression. A positive but weaker association was demonstrated with b-carotene. No association was found for vitamin E, Be, Be, niacin or foliate.
Willow bark tea has been used since antiquity for the treatment of pain, fever, and gout. The powdered bark remains a popular ingredient in over-the-counter anti rheumatic preparations because of its salicin content, a source of salicylic acid. It efficacy in relieving pain in osteoarthritis of the knee and hip has been demonstrated in randomized, double-blind, placebo-controlled trials.
Studies have shown that osteoarthritis pain can be significantly alleviated with iridoid glycoside harpagoside, the presumed active ingredient in devil's claw (Harpagophytum procumbens) remedies. Double-blind trials with subjects taking 2.0 to 2.4 gm/day of powdered Harpagophytum extract, containing 0.3 to 0.7 gm of harpagoside, for one to two months showed a reduction in pain score and an increase in mobility. Short-term tolerability was high, but long-term efficacy and side effects remain unknown.
Fever few (Tanacetum parthenium), another traditional arthritis remedy long used in Europe and North America, is believed to have antipyretic as well as anti-inflammatory activity. However, in the single clinical trial conducted thus far in 41 women with rheumatoid arthritis treated with powdered extract of T. parthenium leaves, none showed any improvement in pain, stiffness, or number of swollen or tender joints.
CHINESE THUNDER GOD VINE
The roots, leaves, and flowers of the Chinese thunder god vine (Tripterygium wilfordii) have been in use in Chinese medicine in the 1500s. It fell into disfavor (perhaps because of toxicity) and for the next four centuries was used only as an agricultural insecticide. Medical interest was revived during the Cultural Revolution. Since then, it has been used for a host of rheumatologic disorders, including rheumatoid arthritis, SLE, Henoch-Schonlein purpura, Sweet syndrome, scleroderma, Behcet's disease, and psoriatic arthritis.
Its therapeutic activity probably derives from diterpenoid components with epoxide structures. T2, a chloroform-methanol extract, and EA, an ethyl acetate extract of Tripterygium roots, have a anti-inflammatory and immunosuppressive effects. The active ingredients in these extracts, triptolide and tripdiolide, inhibit production of cytokines and other inflammatory mediators.
Most of the information on the medical uses of Tripterygium comes from uncontrolled clinical trials and retrospective studies. In actively treated patients, ESR and rheumatoid factor decreased. However, considerable toxicity has been documented. Many women experienced amenorrhea; men may experience azoospermia. Treatment-related deaths have also occurred as a result of myocardial damage, renal failure, and hypotensive episodes related to severe gastrointestinal side effects.
Arthritis patients use acupuncture primarily for its analgesic effects. After a 1998 consensus conference review of available data, the National Institute of Health concluded that acupuncture is promising for control of postoperative pain and chemotherapy-associated nausea and vomiting. The NIH also approved its use as primary or adjunctive therapy for such disorders as tennis elbow, fibromyalgia, myofascial pain, osteoarthritis, low back pain, and carpal tunnel syndrome.