Efficacy of acupuncture in refractory irritable bowel syndrome patients: a randomized controlled trial

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder affecting 10-20% of the world's population, characterized by abdominal pain and altered bowel habits without apparent organic lesions. When patients fail to respond adequately to conventional treatments for more than 12 months, the condition is considered refractory, creating an urgent need for effective alternative therapies. This multicenter, randomized, sham-controlled trial was the first to specifically investigate the efficacy of acupuncture in patients with refractory IBS in the context of ongoing usual care.

The study included 170 patients from six centers in China, all diagnosed with refractory IBS according to the Rome IV criteria and with a history of treatment failure to at least six weeks of conventional dietary and pharmacologic intervention. Participants were randomized into two groups: true acupuncture (85 patients) and sham acupuncture (85 patients). The true acupuncture protocol used specific bilateral points based on Traditional Chinese Medicine theory: Tianshu (ST-25), Shangjuxu (ST-37), Zusanli (ST-36), and Neiguan (PC-6), with manipulation to elicit the 'deqi' sensation. The sham group received superficial needling at sites that did not correspond to traditional acupuncture points or meridians, without manipulation to induce deqi.

Primary outcomes were measured by the change in the IBS Symptom Severity Scale (IBS-SSS) from baseline to week 4. The true acupuncture group demonstrated a mean reduction of 140.0 points (95% CI: 126.0 to 153.9) compared with 64.4 points (95% CI: 50.4 to 78.3) in the sham group, yielding a significant between-group difference of 75.6 points (95% CI: 55.8 to 95.4). The response rate, defined as ≥50-point reduction in IBS-SSS, was 90.6% in the acupuncture group versus 44.7% in the sham group, a 45.9% difference that remained statistically significant.

Secondary outcomes reinforced the superiority of true acupuncture. All individual IBS-SSS domains showed significantly greater improvement in the acupuncture group: abdominal pain severity, pain frequency, abdominal distension, satisfaction with bowel habits, and interference with daily life. IBS-related quality of life also improved substantially, with an 8.4-point between-group difference on the IBS-QOL scale. Importantly for clinical practice, the benefits of acupuncture were sustained throughout the 4-week follow-up period, with persistent differences at weeks 6 and 8, suggesting durable effects beyond the active treatment period.

The safety profile was excellent, with mild and transient adverse events reported in only 9 patients in the acupuncture group (subcutaneous hematoma and residual needle sensation) and no serious adverse events. The dropout rate was low (6%), indicating good treatment acceptability. The study demonstrated that acupuncture three times per week for four weeks represents a feasible and well-tolerated protocol for this challenging patient population.

The clinical implications are significant, especially considering that patients with refractory IBS have limited therapeutic options. Acupuncture proved to be a safe and effective adjunctive therapy that can be integrated into usual care, offering clinically relevant benefits across multiple domains. The findings support including acupuncture in treatment guidelines for refractory IBS, particularly for patients who do not respond adequately to conventional therapies. The magnitude of the observed effect — with more than 90% of patients showing a clinically significant response — suggests that acupuncture may fill an important therapeutic gap in the management of this challenging condition.