Adding Paroxetine May Not Improve CBT for Social Anxiety

Many treatment options are available for social anxiety disorder (SAD), but as highlighted in a 2014 network meta-analysis (Psychiatric News, November 18, 2014) cognitive-behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) are generally considered the most effective.

But how might these two options directly compare, or work in tandem to treat SAD? There has not been much research in this area, but a clinical study published October 15 in Psychotherapy and Psychosomatics suggests that CBT may be the most effective treatment for SAD compared with the SSRI paroxetine and combined SSRI/CBT treatment.

This study involved 102 adult patients with SAD who were evenly divided into the four treatment groups: 20 to 60 mg paroxetine/day for 26 weeks; 12 CBT sessions, each with a maximum duration of 60 minutes (with the possibility of two booster sessions, if needed), over 12 weeks; paroxetine for 26 weeks with 12 CBT sessions; or placebo pill. The participants, who were naïve to either SSRIs or CBT to reduce any preconceptions about effectiveness, were then assessed after 12 weeks of treatment and again one year from the time treatment ended.

To assess patient improvement, Hans Nordhal, Ph.D., a professor of psychology at the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway, and colleagues evaluated patients using the Fear of Negative Evaluation Questionnaire (FNE), with additional anxiety outcomes and interpersonal problems assessed by the Liebowitz Social Anxiety Scale (LSAS), Beck Anxiety Inventory, and Inventory of Interpersonal Problems, respectively.

As might be expected, CBT—alone or in combination with paroxetine—yielded strong and sustained improvements in anxiety and interpersonal symptoms relative to placebo at the end of treatment. However, only CBT alone was found to be superior to paroxetine and placebo in the various measurements. Patients who received CBT alone or the combination treatment had similar outcomes at the one-year follow-up, though solo CBT was superior to combination therapy on the LSAS.

Recovery rates (with criteria of at least a six-point improvement on the FNE and an overall score of 15 or less) at 12 months were higher for the CBT group (68 percent) compared with the groups that received combination therapy (40 percent), paroxetine (24 percent), or placebo (4 percent).

“We investigated many outcomes, but could not find any advantage in combining these two treatments,” Nordhal and colleagues wrote.

Stefan Hoffman, Ph.D., director of the Social Anxiety Program at Boston University, who was not involved with the study, pointed out several strengths of the trial, including the use of a CBT approach that used metacognitive strategies (making the patients think about how they think) to reflect more modern CBT practice. The study also included people with avoidant personality disorder (which is akin to SAD but encompasses broader and more severe symptoms), who are typically excluded from such trials, he noted.

However, he told Psychiatric News that it was a bit unusual that the authors chose FNE as the main outcome. “The FNE is a self-reported measure, so it may not be the best reflection of anxiety outcomes compared with independent evaluations done by clinicians.”

Nonetheless, he said he was not surprised that combining CBT and paroxetine did not prove more beneficial. “It is a plausible concept that adding two moderately effective treatments would be better than either alone, but this has not been substantiated by evidence,” he said.

Hoffman explained that while psychotherapy and pharmacology are different approaches, their neurological underpinnings are similar—meaning that just as two turtles side by side will not reach a finish line any faster than one, combining psychotherapy and pharmacology may fail to boost recovery.

He suggested that combination efforts for anxiety disorders should focus more on augmentation agents like d-cycloserine, which can facilitate the extinction of fearful memories and possibly accelerate CBT improvements.

Hoffman did caution, however, that more research is needed to see if some patients might benefit from a combination of CBT and SSRIs. He noted that, as in other trials, the study by Nordhal and colleagues excluded people with comorbid psychiatric illness such as depression, which is common in anxiety disorders.

Judith Beck, Ph.D., the president of the Beck Institute for Cognitive Behavior Therapy in Philadelphia, noted that while it is important for CBT practitioners to be aware of evidence that suggests medication may interfere with CBT, there are limitations to what some of them may be able to do with such information.

“The majority CBT practitioners cannot prescribe medications, so it would be unethical for us to suggest a patient should initiate or stop their treatments,” she told Psychiatric News. If there is evidence that a medication may interfere with CBT, she said she relays this information to a patient but advises them to discuss advantages and disadvantages of the medication with their physician.

The other confounding issue is that a hallmark of CBT is the collaboration between the patient and therapist. “I see patients who’ve never been on a medication and never want to start, and others who never want to stop taking medication,” she said. “And for CBT to be effective, you have to work within your patient’s goals and desires.”

This trial was supported by the departments of Psychology and Neuroscience at NTNU. ■