Glucosamine No Better Than Placebo for Lumbar Spine Pain

An Interview With the Lead Study Author

By G. Douglas Andersen, DC, DACBSP, CCN

Those of you who subscribe to journals know that as soon as they come, we scan the table of contents to see which articles look interesting. When I got my July 7, 2010 copy of the Journal of the American Medical Association (JAMA), the first article was about glucosamine for degeneration of the lumbar spine.¹ I went straight to the article, knowing it would be the topic for this DC article, and started reading.

The Study

Patients were recruited via referrals "by general practitioners, physiotherapists, chiropractors, and self referrals." When I saw "chiropractors," I stopped and wondered who did the study since we (chiropractors) are seldom mentioned (which happened later in the same issue) in journals such as JAMA. When I read that the lead author was a chiropractor, I was just plain stunned. Instead of being upset that glucosamine did no better than a cellulose placebo for the relief of lower back pain caused by osteoarthritis (OA) of the lumbar spine, I was pleased that a chiropractor took the lead on a topic that the chiropractic profession should take the lead on. Rather than break down the numbers like I've done with other glucosamine studies from major biomedical journals, I went directly to the source and contacted Dr. Phillip Wilkens, who was gracious enough to be interviewed.

G. Douglas Andersen (GDA): How unusual is it for the lead author to be a chiropractor for an original article in JAMA?
Phillip Wilkens (PW): It is rather unusual. I thought I was the first one; however, at least one other person has been the lead author in a JAMA article.

GDA: Unusual is a huge understatement. Not only were you the lead author, but your study also prompted both an editorial (papers with important results often generate an editorial commentary) and the subject of the patient page. (Each issue, JAMA has a one-page illustrated summary of a problem or condition that relates to one of that week's topics.) I was impressed by how the editor treated you, and I quote, "The results of the high-quality clinical trial by Wilkens, et al., carefully evaluating a widely used treatment for chornic low back pain were disappointing but should not be discouraging."² I was dismayed with the Osteoarthritis of the Lumbar Spine segment.³ That piece does what we have come to expect. They mention every possible intervention - acupuncture, physical therapy, pain doctor, rheumatologist, massage, surgery, lifestyle, self-care and medications -- OTC, Rx, injectables - but not chiropractic when discussing treatment options. Any comment?
PW: I don't believe we were purposefully omitted. Rather, MDs have little or no training working with, and referring to, chiropractors. This is changing slowly and if more chiropractors would contribute to scholarly publications, I believe it would improve our credibility as a profession.

GDA: How many years did it take to go from idea to publication?
PW: The idea for the research project arose in 2005, so it took five years to conduct the trial, write the article and get it submitted and accepted.

GDA: In your study, 1,500 mg of glucosamine sulphate did no better than placebo for patients with low back pain with MRIs that showed OA of the lumbar spine. Do you think it's possible that some of the people who felt better on glucosamine are responders, and we need to figure out how to identify that group?
PW: That is certainly possible. The problem is [identifying] the responders before we recommend the product, especially since other subjects responded to our cellulose placebo.

GDA: For years, most of the good papers I read on glucosamine were on the knee. These papers led clinicians and the supplement industry to extrapolate that it would work on spinal degeneration. Please comment.
PW: That was also our initial hypothesis. Since glucosamine may affect knee OA and OA has similarities in all joints, we wanted to investigate the effect on low back pain. I was surprised at the results.

GDA: Please explain what the results mean and what they don't mean.
PW: The results only apply to chronic low back pain in patients with findings of spinal degeneration. The results indicate that glucosamine sulfate is not better than placebo in reducing pain-related disability in patients with chronic low back pain. The results do not say anything about the effect of glucosamine on other joints.

GDA: Have you used glucosamine in your practice?
PW: I recommend glucosamine for knee patients for at least six months. If the patients feel an effect, they may continue. If not, I recommend they stop. Prior to the results of my study, I also recommended glucosamine for spinal degeneration.

GDA: The results will definitely lead many patients to ask their providers about glucosamine's clinical utility. What message do you have for the DC who will want to say, "The chiropractor who did the study says...?"
PW: Glucosamine may be beneficial (knee, hip, etc.), but is probably not going to help pain caused by spinal osteoarthritis. I would recommend other interventions or no interventions, if you believe that is the correct approach.

GDA: What do you say to providers and patients who insist glucosamine helps their back pain?
PW: That they are probably part of an undefined and undiagnosed subgroup responding to glucosamine.

GDA: Have you (or the study) been criticized by parties with secondary gain issues (that is, your paper hurts their income)?
PW: The industry has been very polite and professional, so we have had no problems with them.

GDA: Tell readers about your background and how you got into chiropractic.
PW: I was introduced to chiropractic by my uncle, who talked about chiropractic a great deal. He is not a chiropractor, but a patient. My background is chiropractic studies from Australia and United Kingdom. I am now finishing my PhD at the University of Oslo [Norway].

GDA: Explain to our North American readers the difference between the MChiro and DC degree.
PW: In Europe, when you graduate from a university, you get a degree which is called Masters of Chiropractic. In the U.S., the DC is usually from a college devoted only to chiropractic. However, the academic difference is probably minimal.

GDA: I noticed you are affiliated with a hospital. Do you see patients? If so, explain the process.
PW: I am associated with the hospital for research purposes only, and see patients in a private practice. My typical day is three to four hours of research-related work and three to four hours with patients and the work they generate.

Comment

I don't care what the truth is as long as I know it. Was I disappointed with the results? You bet. What will I tell my patients? The evidence remains that for arthritic extremities, glucosamine is worth a try. Based on this study, I will advise my patients interested in natural approaches for low back pain caused by degeneration to choose poly-ingredient formulas that contain more than just glucosamine. I hope these results will spur the research community to repeat studies like this one using combination preparations to determine if the addition of substances like chondroitin, MSM, fatty acids, hyaluronan or anti-inflammatory herbs can make a difference for those with spinal degeneration.

References

1. Wilkens P, Scheel IB, Grundnes O, et al. Effect of glucosamine on pain-related disability in patients with chronic low back pain and degenerative lumbar osteoarthritis: a randomized controlled trial. JAMA, July 2010;304(1):45-52.
2. Avins AL. "Glucosamine and the Ongoing Enigma of Chronic Low Back Pain" (editorial). JAMA, July 2010;304(1):93-4.
3. Chang HJ, Lynm C, Glass RM. "Osteoarthritis of the Lumbar Spine" (patient page). JAMA, July 2010;304(1):114.

---

Click here for more information about G. Douglas Andersen, DC, DACBSP, CCN.