BAD ABBACH, Germany—Consumer media reports widely touted a recent a study of acupuncture for low back pain (LBP) but missed the key point: "true" acupuncture performed according to the principles of traditional Chinese medicine was no better than fake acupuncture done by slightly pricking nonacupuncture points. Michael Haake, PhD, MD, and colleagues report in Archives of Internal Medicine that either type of needling was more effective than conventional therapy.¹

"The underlying mechanism may be a kind of superplacebo effect produced by placebo and all nonspecific factors working together," Dr. Haake suggests.

Does Occam's razor point to a placebo effect?

The authors explain that the comparison of sham versus true acupuncture was intended to differentiate the physiologic from the psychological effects of acupuncture, such as positive patient expectations, more intensive physician contact, and the experience of an invasive technique. Because the sham versus true acupuncture techniques were indistinguishable to the patients, "any differences in outcomes between the two forms must be attributable to specific treatment effects," they write.

Since outcomes were not different, a reasonable conclusion might be that there were no treatment effects associated with "true" acupuncture. The researchers avoid concluding that acupuncture causes only a placebo effect, however. Instead, they suggest that they have happened on an alternative "active" form of acupuncture with "a common underlying mechanism that may act on pain generation, transmission of pain signals, or processing of pain signals by the central nervous system and that is stronger than the action mechanism of conventional therapy."  

They admit that "the unexpected finding of similar effectiveness of sham and verum acupuncture forces us to question the underlying action mechanism of acupuncture and to ask whether the emphasis placed on learning the traditional Chinese acupuncture points may be superfluous."

Whatever is happening is more effective than convention LBP care

"Almost half of the patients in the acupuncture groups but only one-fourth of patients in the conventional therapy group benefited," Dr. Haake reports.  At 6 months, significant pain relief was reported by 47.6% of the acupuncture patients, 44.2% of the sham acupuncture group, and 27.4% of the conventional therapy group compared with baseline.

This study, part of a project known as the German Acupuncture (GERAC) trials, was a patient- and observer-blinded randomized controlled trial of 1162 patients aged 18 to 86 years with a history of chronic LBP (mean duration 8 years). Patients underwent ten 30-minute sessions of their assigned treatment, usually twice per week. The primary outcome variable was response after 6 months, defined as at least a 33% improvement in pain-related items on the Von Korff Chronic Pain Grade Scale or a 12% or better improvement in the Hanover Functional Ability Questionnaire.

Patients randomized to conventional treatment received oral or injected analgesics, as well as heat and physical therapy, massage, and exercise. Those randomized to either real or sham acupuncture were treated with identical sterile, disposable needles without electrical stimulation of moxibustion. The true acupuncture group had 14 to 20 needles inserted to a depth of 5 mm to 40 mm at points "chosen individually on the basis of traditional Chinese medicine diagnosis, including tongue diagnosis." The sham acupuncture group had 14 to 20 needles inserted to a depth of only 1 mm to 3 mm at points along the back and lower limbs that avoided all known acupuncture points.

"[T]he effectiveness of sham acupuncture and the principle of nihil nocere suggest that a discussion is called for about the necessary depth of insertion of acupuncture needles," Dr. Haake concludes.  Another point awaiting investigation is whether both the true and the sham acupuncture needling used in this trial might generate competing signals able to block pain messages to the brain.

Table. Low Back Pain Treatment Outcomes After 6 Months

Treatment	Response Rate (%)	Differences (%)	P
Acupuncture	47.6
Sham acupuncture	44.2
Conventional care	27.4
Real vs sham		3.4	.39
Real vs conventional care		20.2	<.001
Sham vs conventional care		16.8	<.001

Source: Haake et al.¹

Reference