Natural anti-inflammatories used widely
May hold potential harm for orthopaedic patients
By William D. Cabot, MD
Do you know that over half of your patients are using some modality of complementary or alternative medicine (CAM)? More often than not, our patients do not tell us about their use of CAMnor do we ask. A report in the Journal of the American Medical Association tells us, that in 1997, 50 million adults took both prescription drugs as well as herbal medicines. A significant percentage of the same patients did not disclose this fact to their examining physician. Many of these patients have arthritis and various other inflammatory disorders.
There is evidence ranging from anecdotal to reasonably convincing data that some herbs and supplements have efficacy in treating some inflammatory diseases. Many of our patients make the potentially dangerous assumption that "natural" remedies are innocuous. They are not.
Many herbs and supplements have a very real potential of enhancing bleeding and are therefore extremely dangerous when used during the perioperative period, or when anticoagulants or any medications that have bleeding as a side effect are taken concurrently. The Food and Drug Administration does not regulate herbs and supplements as it does drugs. There are many potential problems related to uncertain composition, ill-defined ingredients and underreported side effects.
Among the many herbs and supplements that some CAM practitioners and their users believe can exert an anti-inflammatory or analgesic effect (if not always on the basis of good scientific studies), are the following: turmeric (Curcuma longa) boswellia (Bosellia serrata), stinging nettle (Urtica dioica), white willow bark (Salix alba), devils claw (Harpagophytum procumbens), quercetin, resveratrol, cayenne, omega-3 fatty acids, cats claw (Uncaria tomentosa), ginger, and SAMe (S-adenosylmethionine).
These herbs and supplements are thought to act through one of several mechanisms, whereas nonsteroidal anti-inflammatory drugs most typically act as cyclooxygenase inhibitors. Some herbs and supplements inhibit the production of pro-inflammatory eicosanoidsprostaglandins and/or leukotrienes. Others decrease production of nitric oxide or the pro-inflammatory cytokines such as tumor necrosis factor (TNF-alpha) and interleukin one beta (IL-1 beta). Antioxidants, of which there are many, also play a role in the anti-inflammatory process by decreasing the production of free radicals, which, by virtue of their scavenging effect, play a significant part in the inflammatory process. Antioxidants are mainly effective when taken prior to an inflammatory process and not after.
There is not sufficient evidence- based science to justify using most of these substances. For the most part, their use is based upon centuries of anecdotal commentary. Most human studies suffer from small sample size and/or lack of controls. However, the National Institutes of Health (NIH) is providing over $100 million this year for well-designed research into the safety, efficacy and mechanism of action of many CAM modalities, including herbals and supplements.
Glucosamine and chondroitin sulfate are supplements of particular interest to orthopaedic surgeons. They have been widely marketed and used by our patients and our colleagues. Both glucosamine and chondroitin sulfate are primarily used as chondroprotective agents, not anti-inflammatory agents. Glucosamine has mild anti-inflammatory properties, but does not inhibit the arachidonic acid cascade. Chondroitin sulfate may be anti-inflammatory by decreasing IL-1 beta production and blocking complement activation.
Both of these agents are relatively safe. According to correspondence by Drs. W. Arnold and E. Arnold published in the September/October 2001 issue of the Journal of American Academy of Orthopaedic Surgeons, "The preponderance of scientific and clinical evidence supports the inclusion of glucosamine sulfate, in a dose of 1500 mg daily, as a component of a comprehensive medical management program for osteoarthritis of the knee, such as that devised by the American College of Rheumatology." A major NIH/National Institute of Arthritis and Musculoskeletal and Skin Diseases study, which will be completed in 2004, will give us a much more explicit understanding of the safety and efficacy of these supplements.
Learn the pharmacology
With the burgeoning interest in and utilization of CAM modalities by our patients, it is essential that we educate ourselves about the pharmacology of the commonly used herbs and supplements. When we take a patients history, we must ask him or her about their use of these substances as routinely as we inquire about their use of other medications.
To aid you in this effort, the CAM Committee has developed a special section of the AAOS Web site to tell you about these treatment alternatives. It can be found at http://www3.aaos.org/ courses/cam/camtoc.htm. There you will find outlined the potential risks of some CAM products in a drug/herb interaction chart. It also includes the FDAs "Tips for the Savvy Supplement User," a selection of orthopaedically relevant CAM articles, answers to frequently asked questions and information about the Dietary Supplements Health and Education Act of 1994. There are many sources of valid information about these products so we also have included on the site links to other reliable sources of CAM information.
For those of you who refer patients for information about orthopaedic conditions to the AAOS patient education Web site, Your Orthopaedic Connection, the wellness section features the CAM drug/herb interaction chart. The knee section features an article on glucosomine and chrondroitin sulfate. The AAOS also sells a book for patients on "Alternative Therapies" published by the Arthritis Foundation.
William D. Cabot, MD, is an AAOS Fellow and frequent guest and contributor to the AAOS CAM Committee. He currently practices at The Center for Integrative Medicine in Easton, Md.