Long-term outcome of cognitive behaviour therapy clinical trials in central Scotland

• Published in: Health technology assessment (Winchester, England) England), 2005-11, Vol.9 (42), p.1-174
• Main Authors: Durham, R C, Chambers, J A, Power, K G, Sharp, D M, Macdonald, R R, Major, K A, Dow, M Gt, Gumley, A I
• Format: Article
• Language: English
• Subjects: Anti-Anxiety Agents - therapeutic use; Anxiety Disorders - economics; Anxiety Disorders - therapy; Cognitive Therapy; Cost-Benefit Analysis; Humans; Randomized Controlled Trials as Topic; Schizophrenia - economics; Schizophrenia - therapy; Scotland; Severity of Illness Index
• ISSN: 1366-5278; 2046-4924; 1366-5278
• DOI: 10.3310/hta9420

To establish the long-term outcome of participants in clinical trials of cognitive behaviour therapy (CBT) for anxiety disorders and psychosis, examining the effectiveness and cost-effectiveness associated with receiving CBT in comparison with alternative treatments. An attempt was made to contact and interview all of the participants in eight randomised, controlled, clinical trials of CBT for anxiety disorders and two randomised, controlled, clinical trials of CBT for schizophrenia conducted between 1985 and 2001. Case note reviews of healthcare resources used in the 2 years prior to entering the trials and the 2 years prior to follow-up interview were undertaken. Mixed rural and urban settings in five localities in central Scotland. Anxiety disorder trials were conducted mainly in primary care and included three with generalised anxiety disorder, four with panic disorder and one with post-traumatic stress disorder (PTSD). The psychosis studies (one on relapse prevention and one with chronic disorder) were conducted in secondary care. Of the 1071 entrants to the 10 studies, 489 agreed to participate (46% of original entrants, 52% of those available to contact). Follow-up interviews took place between 1999 and 2003, 2-14 years after the original treatment. Interviews for Trials 1-8 were conducted by a research psychologist blind to original treatment condition. Interviews for Trials 9 and 10 were conducted by community psychiatric nurses also blind to treatment condition. Case note reviews were completed following the interview. For Trials 1-8 the main interview-based outcome measures were: Anxiety Disorders Interview Schedule-DSM-IV for diagnosis and co-morbidity, Clinical Global Severity (0-8) and the Hamilton Anxiety Rating Scale. The main patient-rated measures were: Brief Symptom Inventory, SF-36 II, Clinical Global Improvement (1-7), and the Positive and Negative Affect Scale. For Trials 9 and 10 the primary outcome measure was the interview-based Positive and Negative Syndrome Scale (PANSS). For the anxiety disorder studies (Trials 1-8), over half of the participants (52%) had at least one diagnosis at long-term follow-up, with significant levels of co-morbidity and health status scores comparable to the lowest 10% of the general population. Only 36% reported receiving no interim treatment for anxiety over the follow-up period with 19% receiving almost constant treatment. Patients with PTSD did particularly poorly. There was a 40% real increase in h