Meta-analysis: acupuncture for low back pain.

BACKGROUND:

Low back pain limits activity and is the second most frequent reason for physician visits. Previous research shows widespread use of acupuncture for low back pain.

PURPOSE:

To assess acupuncture's effectiveness for treating low back pain.

DATA SOURCES:

Randomized, controlled trials were identified through searches of MEDLINE, Cochrane Central, EMBASE, AMED, CINAHL, CISCOM, and GERA databases through August 2004. Additional data sources included previous reviews and personal contacts with colleagues.

STUDY SELECTION:

Randomized, controlled trials comparing needle acupuncture with sham acupuncture, other sham treatments, no additional treatment, or another active treatment for patients with low back pain.

DATA EXTRACTION:

Data were dually extracted for the outcomes of pain, functional status, overall improvement, return to work, and analgesic consumption. In addition, study quality was assessed.

DATA SYNTHESIS:

The 33 randomized, controlled trials that met inclusion criteria were subgrouped according to acute or chronic pain, style of acupuncture, and type of control group used. The principal [correction] measure of effect size was the standardized mean difference, since the trials assessed the same outcome but measured it in various ways. For the primary outcome of short-term relief of chronic pain, the meta-analyses showed that acupuncture is significantly more effective than sham treatment (standardized mean difference, 0.54 [95% CI, 0.35 to 0.73]; 7 trials) and no additional treatment (standardized mean difference, 0.69 [CI, 0.40 to 0.98]; 8 trials). For patients with acute low back pain, data are sparse and inconclusive. Data are also insufficient for drawing conclusions about acupuncture's short-term effectiveness compared with most other therapies.

LIMITATIONS:

The quantity and quality of the included trials varied.

CONCLUSIONS:

Acupuncture effectively relieves chronic low back pain. No evidence suggests that acupuncture is more effective than other active therapies.