JMIR Publications

ABSTRACT

Background:

Transdiagnostic Internet-delivered Cognitive Behavioral Therapy (iCBT) for emotional disorders has been shown to be effective in specialized care in the short term. However, less is known about its long-term effects in this specific setting. In addition, predictors of long-term effectiveness may help to identify what treatments are more suitable for certain individuals.

Objective:

In this study we aimed to a) analyze the long-term effectiveness of transdiagnostic iCBT compared to treatment as usual in specialized care, and b) to explore predictors of long-term effectiveness

Methods:

Mixed models were performed to analyze the long-term effectiveness and predictors of transdiagnostic iCBT (n= 99) versus treatment as usual (n = 101) in public specialized mental health care. Outcomes included symptoms of depression and anxiety, health-related quality of life (QoL), behavioral inhibition/behavioral activation, comorbidity, and diagnostic status (i.e., loss of principal diagnosis) from baseline to one-year follow-up. Sociodemographic characteristics (sex, age, education), and clinical variables (principal diagnosis, comorbidity, and symptom severity at baseline) were selected as predictors of long-term changes.

Results:

compared to baseline, EmotionRegulation was more effective than treatment as usual (TAU) in improving symptoms of depression (b= -4.16, s.e. = 1.80, 95% CI [-7.68, -.67]) , health-related QoL (b= 7.63, s.e. = 3.41, 95% CI [1.00, 14.28]), diagnosis status (b= -.24, s.e. = .09, 95% CI [-1.00, -.15]), and comorbidity at one-year follow-up (b= -.58, s.e. = .22, 95% CI [-1.00, -.15]). Pre-treatment to follow-up anxiety symptoms improved in both EmotionRegulation and TAU, but no significant differences were found between groups. Regarding the predictors of long-term effectiveness, compared to treatment as usual, a) higher health-related QoL at follow-up was predicted by a baseline diagnosis of anxiety, male sex, and the use of psychiatric medication; b) fewer comorbid disorders at follow-up were predicted by older age and higher baseline scores on health-related QoL; and c) fewer depressive symptoms at follow-up were predicted by baseline diagnosis of depression. However, this pattern was not observed for baseline anxiety diagnoses and anxiety symptoms.

Conclusions:

The results support that transdiagnostic iCBT is more effective than treatment as usual to target depressive symptoms among patients with emotional disorders. Anxiety symptoms remained stable at one-year follow-up, with no differences between groups. Results on predictors suggest that some groups of patients may obtain specific gains after transdiagnostic iCBT. Specifically, and consistent with the literature, patients with baseline depression improved their depression scores at follow-up. However, this pattern was not found for baseline anxiety disorders. Future studies on iCBT should focus on studying the predicting role of sociodemographic and clinical variables, but also the data associated with program usage in long-term treatment outcome. Clinical Trial: ClinicalTrials.gov NCT02345668; https://clinicaltrials.gov/ct2/show/NCT02345668