Long-term effectiveness of CBT for youth with anxiety disorders

 Kodal, A., Fjermestad, K., Bjelland, I., Gjestad, R., Öst, L.-G., Bjaastad, J. F., Haugland, B. S. M., Havik, O. E., Heiervang, E., & Wergeland, G. J. (2018). Long-term effectiveness of cognitive behavioral therapy for youth with anxiety disorders. Journal of Anxiety Disorders, 53, 58–67. https://doi.org/10.1016/j.janxdis.2017.11.003

Summary by: Inti Van de Vyver

In this study, they wanted to see what the long-term effects of cognitive behavioral therapy (CBT) were for young people with separation anxiety disorder (SAD), social anxiety disorder (SOP), and generalized anxiety disorder (GAD), who were treated in community mental health clinics.

The reason why they started to study this topic was that they found only five previous studies that examined the long-term effectiveness of CBT. Another reason was that they didn't find any studies that looked at the long-term effects in community mental health clinics. They found several short-term studies with positive results, but no long-term studies in these settings (we speak about long-term follow-up when it takes place at least 2 years after treatment).

Lastly, they found that previous studies differed in their reported outcome measures. For example, if someone is in remission from their principal anxiety diagnosis, this doesn't automatically mean that they no longer experience other anxiety-related impairments. These differences make it difficult to compare long-term follow-up studies and have an influence on the generalizability of their findings.

They contacted 179 young people who had participated in a randomized controlled trial, which was conducted in seven different public child and adolescent mental health outpatient clinics. The main inclusion criterion was having a principal diagnosis of SAD, SOP, and/or GAD. There were also some exclusion criteria, such as psychotic disorders and severe conduct disorders.

The participants were evaluated before treatment, after treatment, and at a 1-year follow-up. In the original trial, the CBT groups were compared with people on a waiting list as a control group. However, there was no control group in the long-term follow-up study.

In total, 139 participants took part in the long-term follow-up study. They were between 11 and 21 years old at that time. The researchers looked at the differences between individual CBT and group CBT. The participants were evaluated on average 3.9 years (2.2–5.9 years) after treatment.

The treatment they received was called FRIENDS for Life, which is a cognitive behavioral therapy protocol. They had ten 60-minute individual therapy sessions or ten 90-minute group sessions, depending on the treatment format, and two booster sessions. Parents were also included in the therapy.

First, the researchers wanted to look at the effects of therapy on the participants' diagnoses, especially whether they had lost their principal anxiety diagnosis or all their inclusion anxiety diagnoses. Second, they wanted to find changes in youth- and parent-reported anxiety symptoms, depressive symptoms, and clinical severity ratings. Then, they wanted to compare the outcomes of individual and group therapy.

They found that out of the 139 young people, 53% no longer met the criteria for any of their inclusion anxiety diagnoses at the long-term follow-up. 63% no longer met the criteria for their principal anxiety diagnosis. At post-treatment, these percentages were 27% and 40%, respectively.

In total, 19% of the 139 young people had lost all their inclusion anxiety diagnoses at both post-treatment and long-term follow-up. 40% still had one or more inclusion anxiety diagnoses at both assessment points. Of those participants who had not lost all their inclusion anxiety diagnoses at post-treatment, 45% had recovered completely by the long-term follow-up.

They didn't find any statistically significant differences between individual cognitive behavioral therapy and group cognitive behavioral therapy. However, this doesn't necessarily mean that the two treatment formats are equivalent in every outcome.

The young people who had a principal diagnosis of social anxiety disorder had a lower chance of recovery than those with separation anxiety disorder or generalized anxiety disorder. The researchers also found significant reductions in anxiety symptoms over time.

One limitation of the study was that there was no control group at the long-term follow-up. Also, some participants received additional treatment during the follow-up period. This means that the improvements cannot be attributed only to the original CBT treatment.

The conclusion is that the outcomes of cognitive behavioral therapy for young people with anxiety disorders who were treated in community mental health clinics continued to improve nearly 4 years after treatment. The study also suggests that CBT can have positive long-term outcomes outside specialized research clinics.