From efficacy to implementation : applying internet-delivered cognitive behavioural therapy in the treatment of OCD

Abstract

Background: Obsessive Compulsive Disorder (OCD) and Body Dysmorphic Disorder (BDD) are closely related psychiatric conditions associated with functional impairment across various life domains, an increased risk of suicide, and a significant societal and economic burden. If left untreated, these disorders often become chronic. While Cognitive Behavioural Therapy (CBT) and medication with selective serotonin reuptake inhibitors (SSRIs) are first-line treatments recommended for both OCD and BDD, the availability of CBT is limited in most parts of the world.

Aims: The overall aim of this thesis was to extend previous evaluations of internetdelivered CBT (ICBT) for OCD and BDD, in order to demonstrate the applicability and effectiveness of the treatments and to reach out to a broader spectrum of patients suffering from these disorders. More specifically, the aims of each study were: Study I, to investigate whether therapist-guided and unguided ICBT were non-inferior and costeffective compared to face-to-face CBT; Study II, to evaluate the effectiveness of ICBT for OCD and BDD when implemented in the Swedish health care system; Study III, to examine the clinical characteristics of incompleteness and to use it to predict treatment outcome with ICBT for OCD.

Methods: Study I was a randomised controlled non-inferiority trial that enrolled 120 participants. The participants were randomly assigned to receive 14 weeks of either face-to-face CBT, therapist-guided ICBT, or unguided ICBT for OCD. The primary outcome measure was the clinician rated Yale Brown Obsessive-Compulsive Scale (YBOCS) and the non-inferiority margin was set to 3 points on the Y-BOCS. Symptom severity was measured pre, bi-weekly, post, 3-month (primary end-point) as well as 12 months after treatment. Study II was an effectiveness study with repeated measures (pre, weekly, posttreatment). The RE-AIM implementation framework was used to measure implementation variables according to the elements of reach, effectiveness, adoption, implementation and maintenance. Four-hundred and thirty-four participants were included and received ICBT for OCD (OCD-NET) and 163 participants were included and received ICBT for BDD (BDD-NET). The primary outcome measures for effectiveness were the clinician-rated Y-BOCS and the Y-BOCS for BDD (BDD-YBOCS). Study III used a subsample (n= 167) of participants from Study II who received ICBT for OCD. Baseline incompleteness (feelings of something being not just right or incomplete) was measured with the Obsessive-Compulsive Trait Core Dimensions Questionnaire (OCTCDQ). The primary outcome measure was the clinician rated Y-BOCS and participants were measured pre-, weekly and post-treatment.

Results: In Study I, both therapist-guided and unguided ICBT were found to be costeffective compared to face-to-face CBT. However, the non-inferiority results were inconclusive because the confidence intervals crossed the pre-specified non-inferiority margin of 3 points on the Y-BOCS at the primary endpoint (therapist-guided ICBT, mean Y-BOCS difference= 2.10 points, [90% CI, −0.41 to 4.61]; p= 0.17; unguided ICBT, mean YBOCS difference= 5.35 points [90% CI, 2.76 to 7.94]; p < .001). In Study II, OCD-NET and BDD-NET led to significant reductions in OCD and BDD symptom severity (mean YBOCS reduction= -8.8 points; mean BDD-YBOCS reduction= -11.4 points) and large within-group effect sizes posttreatment (OCD-NET, d= 1.94; BDD-NET, d= 2.07). Eightyseven percent of participants receiving OCD-NET and 78% of participants receiving BDD-NET were treatment completers and participants in both treatment groups reported a high treatment satisfaction at posttreatment (OCD-NET= 87%, BDD-NET= 79%). The implementation also influenced treatment delivery at the clinic and dramatically decreased (by 60-70%) the mean number of patients waiting to receive face-to-face treatment options. In Study III, the underlying emotional construct of incompleteness was positively associated with OCD severity and a higher degree of comorbidity at baseline as well as with symmetry/ordering symptoms. Furthermore, elevated levels of incompleteness predicted worse treatment outcomes with ICBT (B= 0.13, SE= 0.04, [95% CI 0.05 to 0.21], p= 0.002) assessed with the clinician-rated YBOCS. Participants with a high degree of incompleteness had lower probabilities than individuals who scored low on incompleteness of being classified as responders (39% vs. 52%) and remitters (10% vs. 34%).

Conclusions: The results suggest that therapist-guided and unguided ICBT are costeffective alternatives to face-to-face CBT in the treatment of OCD. Future research should focus on investigating the effects and cost-effectiveness of a stepped-care approach to deliver ICBT. The findings further indicate that ICBT for OCD and BDD are effective, acceptable, and safe treatments that can be successfully implemented within the Swedish healthcare system. More research is needed to explore the effectiveness of ICBT in a less specialised implementation context, such as primary care. Incompleteness seems to be an important clinical characteristic in OCD that deserves further investigation and higher levels of incompleteness were found to predict a worse treatment outcome with ICBT.