BACKGROUND: Irritable bowel syndrome (IBS) affects 10-22% of people in the UK. Abdominal pain, bloating and altered bowel habits affect quality of life and can lead to time off work. Current treatment relies on a positive diagnosis, reassurance, lifestyle advice and drug therapies, but many people suffer ongoing symptoms. Cognitive-behavioural therapy (CBT) is recommended in guidelines for patients with ongoing symptoms but its availability is limited.
OBJECTIVES: To determine the clinical effectiveness and cost-effectiveness of therapist telephone-delivered CBT (TCBT) and web-based CBT (WCBT) with minimal therapist support compared with treatment as usual (TAU) in refractory IBS.
DESIGN: This was a three-arm randomised controlled trial.
SETTING: This trial took place in UK primary and secondary care.
PARTICIPANTS: Adults with refractory IBS (clinically significant symptoms for 12 months despite first-line therapies) were recruited from 74 general practices and three gastroenterology centres from May 2014 to March 2016.
INTERVENTIONS: TCBT - patient CBT self-management manual, six 60-minute telephone sessions over 9 weeks and two 60-minute booster sessions at 4 and 8 months (8 hours' therapist time). WCBT - interactive, tailored web-based CBT, three 30-minute telephone sessions over 9 weeks and two 30-minute boosters at 4 and 8 months (2.5 hours' therapist time).
MAIN OUTCOME MEASURES: Primary outcomes - IBS symptom severity score (IBS SSS) and Work and Social Adjustment Scale (WSAS) at 12 months. Cost-effectiveness [quality-adjusted life-years (QALYs) and health-care costs].
RESULTS: In total, 558 out of 1452 patients (38.4%) screened for eligibility were recruited - 186 were randomised to TCBT, 185 were randomised to WCBT and 187 were randomised to TAU. The mean baseline Irritable Bowel Syndrome Symptom Severity Score (IBS SSS) was 265.0. An intention-to-treat analysis with multiple imputation was carried out at 12 months; IBS SSS were 61.6 points lower in the TCBT arm [95% confidence interval (CI) 89.5 to 33.8; < 0.001] and 35.2 points lower in the WCBT arm (95% CI 57.8 to 12.6; = 0.002) than in the TAU arm (IBS SSS of 205.6). The mean WSAS score at 12 months was 10.8 in the TAU arm, 3.5 points lower in the TCBT arm (95% CI 5.1 to 1.9; < 0.001) and 3.0 points lower in the WCBT arm (95% CI 4.6 to 1.3; = 0.001). For the secondary outcomes, the Subject's Global Assessment showed an improvement in symptoms at 12 months (responders) in 84.8% of the TCBT arm compared with 41.7% of the TAU arm [odds ratio (OR) 6.1, 95% CI 2.5 to 15.0; < 0.001] and 75.0% of the WCBT arm (OR 3.6, 95% CI 2.0 to 6.3; < 0.001). Patient enablement was 78.3% (responders) for TCBT, 23.5% for TAU (OR 9.3, 95% CI 4.5 to 19.3; < 0.001) and 54.8% for WCBT (OR 3.5, 95% CI 2.0 to 5.9; < 0.001). Adverse events were similar between the trial arms. The incremental cost-effectiveness ratio (ICER) (QALY) for TCBT versus TAU was £22,284 and for WCBT versus TAU was £7724. Cost-effectiveness reduced after imputation for missing values. Qualitative findings highlighted that, in the CBT arms, there was increased capacity to cope with symptoms, negative emotions and challenges of daily life. Therapist input was important in supporting WCBT. p p p p p p p p
CONCLUSIONS: In this large, rigorously conducted RCT, both CBT arms showed significant improvements in IBS outcomes compared with TAU. WCBT had lower costs per QALY than TCBT. Sustained improvements in IBS symptoms are possible at an acceptable cost. Suggested future research work is longer-term follow-up and research to translate these findings into usual clinical practice.
FUTURE WORK: Longer-term follow-up and research to translate these findings into usual clinical practice is needed.
TRIAL REGISTRATION: Current Controlled Trials ISRCTN44427879.
FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme and will be published in full in; Vol. 23, No. 17. See the NIHR Journals Library website for further project information. The University of Southampton sponsored this study. Funding was received from the NIHR HTA Board and the NIHR Clinical Research Network and support was received from the NIHR Clinical Research Network. Health Technology Assessment
