Cognitive behaviour therapy in addition to antispasmodic treatment for irritable bowel syndrome in primary care: randomised controlled trial

Objective To assess the efficacy of cognitive behaviour therapy delivered in primary care for treating irritable bowel syndrome. Design Randomised controlled trial. Setting 10 general practices in London. Participants 149 patients with moderate or severe irritable bowel syndrome resistant to the antispasmodic mebeverine. Interventions Cognitive behaviour therapy delivered by trained primary care nurses plus 270 mg mebeverine taken thrice daily compared with mebeverine treatment alone. Main outcome measures Primary measures were patients' scores on the irritable bowel syndrome symptom severity scale. Secondary measures were scores on the work and social adjustment scale and the hospital anxiety and depression scale. Results Of 334 referred patients, 72 were randomised to mebeverine plus cognitive behaviour therapy and 77 to mebeverine alone. Cognitive behaviour therapy had considerable initial benefit on symptom severity compared with mebeverine alone, with a mean reduction in score of 68 points (95% confidence interval 103 to 33), with the benefit persisting at three months and six months after therapy (mean reductions 71 points (109 to 32) and 11 points (20 to 3)) but not later. Cognitive behaviour therapy also showed significant benefit on the work and social adjustment scale that was still present 12 months after therapy (mean reduction 2.8 points (5.2 to 0.4)), but had an inconsistent effect on the hospital anxiety and depression scale. Conclusion Cognitive behaviour therapy delivered by primary care nurses offered additional benefit over mebeverine alone up to six months, although the effect had waned by 12 months. Such therapy may be useful for certain patients with irritable bowel syndrome in primary care.