Objective: To assess the effectiveness of acupuncture for the treatment of functional constipation (FC).
Methods: The literature was searched for randomized controlled trials (RCTs) comparing acupuncture with medical treatment; no medical treatment, placebo acupuncture, and sham acupuncture in patients with FC were searched. Data were extracted by two independent reviewers using standard data extraction forms. Risk of bias for each RCT was assessed using a modified Oxford 5-point quality scale. Data were pooled according to intervention and treatment course. Parameters evaluated included effectiveness/invalidity, Cleveland Clinic score (CCS), colon transit time (CTT) and adverse effects.
Results: Nineteen studies involving 1679 participants were eligible for inclusion; of these studies, 16 were published in Chinese and three in English. Risks of bias were high. Acupuncture was significantly superior to medication therapy in short-term (effectiveness/invalidity, P = 0.0009; CCS, P = 0.02) and long-term (effectiveness/invalidity, P = 0.004; CCS, P = 0.04; CCT, P < 0.0001) effectiveness. A short treatment course of less than 15 days was sufficient. The likelihood of adverse effects was significantly lower for acupuncture than for medication therapy (P = 0.002).
Conclusion: Compared with medication, acupuncture was more effective and had a lower adverse effect rate in the treatment of FC. A short treatment course of two weeks was sufficient for a good effect. However, the poor quality of the included trials indicates the need for well-designed RCTs, including adequate sample size and a reasonable placebo control, to assess the effectiveness of acupuncture for FC.