The Washington, D.C.-based Council for Responsible Nutrition said not so fast to a study released this week by the Journal of the American Medical Association showing glucosamine to be no more effective than placebo for managing low-back pain and degenerative osteoarthritis.
The study, led by Norwegian researchers, randomly assigned 250 patients with chronic low-back pain to daily 1,500 mg doses of glucosamine or a look-alike placebo for six months. All participants were subject to MRI scans to verify spine degeneration.
Before the study, patients took a standardized test that measured their back pain on a scale from 1 to 24. Most rated their pain between 9 and 10. Six months later, participants took the same test and while both groups showed improvement, those who took glucosamine didn’t report more relief than those on placebo pills.
“Based on our results, it seems unwise to recommend glucosamine to all patients with chronic low-back pain,” the researchers write in JAMA.
Duffy MacKay, ND, vice president of scientific and regulatory affairs for CRN, said the mysterious nature of what exactly causes low-back pain makes examining the effects of glucosamine on this area of the body difficult.
“To generalize, you can take 100 people with low-back pain and only half will have arthritis, the other half will not,” he said. “Similarly, you can take a group of 100 people experiencing no low-back pain and find evidence of arthritis in half. The presence of arthritis does not always translate to low-back pain because a person may also experience pain due to muscle spasms, bulging disks, poor posture or subluxations for which glucosamine would not be the right treatment. These conditions, in my clinical experience, require a multi-modality approach.”
MacKay pointed to a study published by the American Academy of Family Physicians that showed glucosamine to be beneficial for those with arthritis of the knees—an area of the body, he said, where the cause of pain is much easier to isolate.
The Norwegian study relied on symptoms reports from patients, which MacKay said should have been combined with objective information such as measures of joint space narrowing and inflammatory markers in the blood, to gauge the effects of the supplement.
Additionally, studies are currently examining the role vitamin D plays in inflammation in the body and chronic pain. If those who participated in the study were vitamin-D deficient, this might have also played in role in the researchers’ findings, MacKay said.
While Andrew Avins, MD, MPH, of Northern California Kaiser-Permanente, praised the study as well-designed and well-conducted in an editorial accompanying the study report, he agreed more research is needed to help doctors better understand how to treat low-back pain.
“In the competition for federal research dollars, back pain has not been allocated funding commensurate with its societal cost and quality-of life burden.”