Glucosamine doesn’t ease low back pain: study

A popular anti-arthritis supplement may not help most people with low back pain, according to a new study. Patients in the study got no better after treatment with glucosamine than after treatment with an inactive placebo.

While it’s possible that glucosamine could be beneficial for some people with low back pain, said Philip Wilkens, the lead author on the study and a chiropractor at Oslo University Hospital in Norway, it’s hard to know which ones. Doctors shouldn’t rely on glucosamine for patients with low back pain, he said, but should try other treatments as well.

Glucosamine is one of the most popular supplements used by people with osteoarthritis, which affects more than 20 million people in the U.S. In osteoarthritis, cartilage around the bone breaks down at the joint, causing swelling and pain and making it harder to move. Glucosamine has shown success in treating some kinds of osteoarthritis.

Some low back pain is due to osteoarthritis, but it’s often hard to figure out the cause, the authors note. Glucosamine is taken by about 1 in 4 patients with low back pain, but there hasn’t been much evidence to show that it improves their symptoms.

Wilkens and his colleagues treated 250 outpatients with low back pain at their hospital. In all of those patients, cartilage around part of the spine had started to break down, a sign of osteoarthritis.

Half of those patients were given a standard dose of glucosamine (1500 milligrams per day) and the other half were given placebo pills, but neither group knew which treatment they had. Patients took the pills for six months.

At the beginning of the study and again after six months, the patients filled out questionnaires about their pain and how it interfered with their daily lives. Another six months after the study ended, patients were asked about their pain once more.

At the end of the study and six months later, both patients taking glucosamine and those taking a placebo reported fewer problems related to their back pain than they had at the beginning. However, there was no difference based on what pills they had been taking - people on the placebo improved just as much as people on glucosamine, according to the report, which is published today in the Journal of the American Medical Association.

About 1 in 3 patients in both groups had mild stomach or skin problems, but there were no serious side effects caused by glucosamine.

Part of the improvement in patients’ pain might have happened because all patients were allowed to get other treatment during the study. Common therapies for long back pain include painkillers and anti-inflammatories like ibuprofen and aspirin, physical therapy, and heating pads.

The rest of the improvement, said Wilkens, could be because of the placebo effect, or because patients with chronic pain have periods of getting better and worse, and most were probably in their worse state when they agreed to start the trial.

Glucosamine is thought to help prevent cartilage from breaking down. It’s considered a dietary supplement in the United States, so the FDA does not approve it for medical use. It is, however, approved for medical use in most of Europe. Glucosamine can be bought without a prescription, often for less than 50 cents a day.

The results of the study shouldn’t discourage people who take glucosamine for other types of osteoarthritis, Wilkens said. Because of differences in joints, glucosamine may act differently in other parts of the body, he noted.

“It’s probably helping a lot of people with knee pain,” Wilkens told Reuters Health. But in terms of using it as a treatment for people with low back pain, “our evidence suggests that (they’re) not going to benefit.”

SOURCE:

Journal of the American Medical Association, online July 6, 2010.