HONOLULU - The use of Internet-based cognitive-behavioral therapy could cure half of patients with internalizing mental disorders, including depression, social phobia, panic disorder, and generalized anxiety disorder, a review of data suggests.
Internalizing disorders account for half of mental disorders, Dr. Gavin P. Andrews said at the meeting.
"A quarter of the burden of mental disorders is potentially removable by Internet-based cognitive-behavioral therapy" (CBT), said Dr. Andrews, professor of psychiatry at the University of New South Wales, Sydney, Australia.
"If our profession could get a handle on effective treatment for internalizing disorders, we'd make a fundamental move forward."
Internet-based CBT is a self-help program mediated through the Internet. The patient is in contact through e-mail with the person directing the therapy, which consists of psychoeducation and various exercises are completed online.
Dr. Andrews and his associates conducted a review of the literature and meta-analysis of data from 22 studies of Internet-based CBT involving 1,746 patients. The effect-size superiority over comparison groups was larger than the effect-size superiority traditionally seen for treatment of anxiety disorders using face-to-face CBT or selective serotonin reuptake inhibitors (SSRIs), compared with control groups, he said.
For each of the disorders (depression, social phobia, panic disorder, and generalized anxiety disorder), the number needed to treat with Internet-based CBT in order to show an effect was two (PLoS One2010; 5:el3196).
"Treat two people and one gets better. This is powerful treatment in psychiatry. It's powerful treatment in medicine," said Dr. Andrews, who is a member of the Anxiety, Obsessive-Compulsive Spectrum, Posttraumatic and Dissociative Disorders Work Group for the DSM-5.
The effects of Internet-based CBT appear to last, he added. Although the median follow-up time in the studies was approximately 6 months, some Swedish studies had 18-month follow-up data.
"There was no hint of relapse reported in any study, which is just foreign to my experience," he said. "Depression is supposed to be a relapsing and recurring disorder. What on earth is it doing just disappearing after someone does CBT over the Web? This is not what any of us were trained for."
Dr. Andrews said the study was commissioned by the Journal of the American Medical Association, which declined to publish the results. He and his associates have now published 15 randomized, controlled trials, including approximately 1,500 people showing the effectiveness of Internet-based CBT, he said.
In a recent randomized, controlled study, Dr. Andrews and his associates tested the third iteration of transdiagnostic Internet-based CBT that they developed for patients with depression, social phobia, panic disorder, or generalized anxiety disorder. The study recently published online in advance of print, compared 75 patients who underwent the clinician-guided Internet-based CBT or were on a waiting list for treatment (Be-hav Res. …