In patients older than 50 with moderate or severe chronic knee pain, neither laser nor needle acupuncture conferred benefit over sham for pain or function, according to a study published in the October 1 issue of JAMA.
Rana S. Hinman, PhD, from the University of Melbourne in Australia, and colleagues randomly assigned 282 patients (50 or older) with chronic knee pain to no acupuncture (control group, n = 71) or needle (n = 70), laser (n = 71), or sham laser (n = 70) acupuncture. Treatments were delivered for 12 weeks. Participants and acupuncturists were blinded to laser and sham laser acupuncture. Control participants were unaware of the trial.
Primary outcomes were average knee pain (numeric rating scale, 0 [no pain] to 10 [worst pain possible]; minimal clinically important difference [MCID], 1.8 units) and physical function (Western Ontario and McMaster Universities Osteoarthritis Index, 0 [no difficulty] to 68 [extreme difficulty]; MCID, 6 units) at 12 weeks.
Secondary outcomes included other pain and function measures, quality of life, global change, and one-year follow-up. Analyses were by intention-to-treat using multiple imputations for missing outcome data.
There were no significant differences in primary outcomes between active and sham acupuncture at 12 weeks or one year. Both needle and laser acupuncture resulted in modest improvements in pain compared with control at 12 weeks that were not maintained at one year. Needle acupuncture improved physical function at 12 weeks compared with control but was not different from sham acupuncture and was not maintained at one year. There were no differences for most secondary outcomes and no serious adverse events.
The authors noted that incidental factors such as treatment setting, patient expectations and attitudes (such as optimism), acupuncturist's confidence in treatment, and patient and acupuncturist interaction may influence outcomes.
"In our study, benefits of acupuncture were exclusively attributed to incidental effects, given the lack of significant differences between active acupuncture and sham treatment. Continuous subjective measures, such as pain and self-reported physical function, as used in our study, are particularly subject to placebo responses,” stated investigators. "In patients older than 50 years with moderate or severe chronic knee pain, neither laser nor needle acupuncture conferred benefit over sham for pain or function. Our findings do not support acupuncture for these patients."