By Daniel M. Keller, PhD
San Antonio—Traditional Chinese acupuncture, combined with medical therapy, reduces pain and improves function among patients with osteoarthritis (OA) of the knee, according to a study presented at the annual meeting of the American College of Rheumatology and later published in the Annals of Internal Medicine (2004;141:901-910).
Coinvestigator Marc Hochberg, MD, MPH, head of the Division of Rheumatology and Clinical Immunology, University of Maryland School of Medicine, Baltimore, and colleagues enrolled 570 acupuncture-naïve patients (mean age, 65.5 years) with symptomatic knee OA in a 26-week, randomized, masked, controlled trial. Patients were equally randomized to traditional Chinese acupuncture, sham acupuncture, or education.
Chinese acupuncture patients received 23 treatments with 32 gauge acupuncture needles at 9 standard points around the knee, and needle guide tubes were tapped at 2 sham points on the abdomen. Needles were inserted into the 2 sham points on the sham acupuncture patients, and guide tubes were tapped on the 9 standard points. About one quarter of the patients had 2 symptomatic knees, and both were treated. Patients in the education group received the Arthritis Self-Help Course during 12 weekly 2-hour group sessions.
Because previous acupuncture studies have been criticized for lacking a control group, coinvestigator Lixing Lao, MD, PhD, developed the sham acupuncture technique, according to Dr Hochberg. In real acupuncture “needles are tapped on the skin and then inserted into the skin at prespecified points [and] oftentimes the needles are twirled once they’re in the skin,” he explained. In the sham procedure, needle holder tubes were tapped on the skin at the standard points, while needles were inserted at sham points on the abdomen.
All patients were receiving background analgesic or anti-inflammatory therapy and were advised to continue these as needed. Despite medication, patients had moderate or severe pain on most days of the month before study entry. The primary end point was a change in the WesternOntarioand McMaster Universities Osteoarthritis Index(WOMAC) pain and function scales over time.
The dropout rate was greater in the education group than in the other groups, and statistical comparisons were made only between the traditional and sham acupuncture groups
At the end of 26 weeks, patients in the traditional acupuncture group had a greater reduction in pain subscale scores and an improvement in function subscale scores and in Patient Global Assessment (P = .02) scores compared with the sham group (-3.79 vs -2.92 for pain; -12.42 vs -9.87 for function, respectively). By week 8 of the study, a significant difference was seen on the function scale (P = .01) but not on the pain scale between the 2 groups. At weeks 14 and 26, the traditional acupuncture group showed significant differences on both scales compared with the sham group (pain: P = .02 and P = .003; function: P = .04 and P = .009, respectively). No serious adverse events were associated with either type of acupuncture during the trial.
Interestingly, even the patients receiving sham acupuncture did better than the patients randomized only to the education intervention. Patients in either acupuncture group did not report any decrease in their use of oral medications during the trial. “In the education group, there was actually an increase in background medication used,” Dr Hochberg said.
One possible explanation for the lack of a decrease of medication in the other groups is that patients had been instructed to stay on their medications so as not to introduce an additional variable.
The study was conducted in collaboration with the Center for Integrative Medicine at the University of Maryland School of Medicine using a standard acupuncture protocol that the investigators developed for knee OA, which was modeled after treatment for Bi syndrome in traditional Chinese medicine. A pilot study had confirmed that the standard WOMAC outcomes measures used in clinical trials were responsive to interventions delivered according to the protocol.