Acceptance and Commitment Group Therapy (ACT-G) for health anxiety.

Health anxiety is prevalent (5-9%) in all healthcare settings and in the general population, may have an early onset, and a poor prognosis is seen in severe cases if untreated. Research shows that health anxiety is rarely diagnosed though it causes great suffering for the individual and constitutes a substantial socio-economic burden. Studies have shown that individual cognitive behavioural therapy can relieve health anxiety, but these studies are affected by methodological problems, among others, struggling with patients declining participation, high dropout rates, and some patients not responding to the treatment. Moreover, the impact of health anxiety on sick leave is only scarcely examined. This thesis examines the effect of a new treatment approach, group-based Acceptance & Commitment Therapy (ACT-G) for patients with severe health anxiety in an uncontrolled pilot study and a randomised controlled study (RCT) on ACT-G compared with a 10-month waitlist control condition (paper I and II). Also, the thesis comprises a study on sick leave in patients with health anxiety compared with the general population during a 5-year period and the effect of ACT-G on sick leave. The findings from this study are described in paper III. Patients (age 20-60 years) consecutively referred from general practitioners from Jutland and Funen in the period of March 2010 - April 2012  (approx. 2.5 million citizens) to the Research Clinic for Functional Disorders and Psychosomatics, Aarhus University Hospital, were included. The pilot study included 34 patients, the RCT on ACT-G included 126 patients. In the RCT, patients were block-randomised to either ACT-G and received treatment in 7 groups of each 9 patients in the period of December 2010 - October 2012, or to a 10-month waitlist control group. The primary outcome measure was the Whiteley-7 paper and pencil index for illness worrying. The last paper is based on data on sickness-related benefits from the DREAM social register of transfer benefits and also includes a matched general population register control cohort (n=12,600). In this thesis, we wish to answer the following questions: 1) Is ACT-G an acceptable, feasible and effective treatment approach for patients with severe health anxiety? 2) Can ACT-G improve severe illness worry compared with a waitlist control condition, and are the recently introduced diagnostic criteria for health anxiety acceptable for the patients? 3) Do patients with health anxiety show more sick leave than the general population during a 5-year period, and can ACT-G reduce sick leave measured by transfer benefits (weeks on sickness-related benefits) at 1-year follow-up? As ACT has not previously been examined as treatment approach for health anxiety, we initially conducted an uncontrolled pilot study to test the newly developed manualised program (ACT-G). The study included 34 patients with severe health anxiety and showed very low dropout and high treatment satisfaction. Significant improvements in self-reported illness worry were demonstrated post-treatment, and the results were sustained and further improved at 3- and 6-months follow-up compared to baseline. The subsequent RCT found high acceptance of the diagnosis of health anxiety. All patients (except 1) accepted the diagnosis as the right diagnosis to fit their ailment, and the majority of the patients found that the diagnosis helped them to better understand their symptoms. In an intention-to-treat analysis, ACT-G showed significant effect in the improvement of self-reported illness worry and other secondary measures compared with a waitlist control condition, both post-treatment and at 10-month follow-up (6 months post-treatment). The results were considered clinically significant as 2/3 of the patients in ACT-G at follow-up had demonstrated a pre-defined treatment response, and ¼ of the patients were considered to no longer have clinical case status. Furthermore, the number needed to treat was found to be 2.4. Patients with severe health anxiety showed significantly more weeks on sickness-related benefits than matched individuals from the general population during the 5 years prior to entering the RCT. This difference was stable until an estimated cut-point at 1 year before enrolment, where patients with health anxiety showed further increase in sickness-related-benefits. At one-year follow-up (8 months post-treatment), we did not find a significant difference between ACT-G and the waitlist group in weeks on sickness-related benefits. Post-hoc analysis, however, revealed a significant decrease in weeks on sickness-related benefits for ACT-G during the 2 years after randomisation. In conclusion, the thesis suggests that ACT-G is both an acceptable and effective treatment approach for patients with severe health anxiety. Hopefully, these findings can contribute to the future research and identification of which treatment approaches are the most effective and for which patients and contribute to tailored, early interventions. This may possibly prevent development of otherwise chronic symptoms, increase the quality of life for the patients, and potentially reduce socio-economic costs.