Another systematic review including 43 studies with a total of 4,133 subjects and minimum follow-up of 6 months was abstracted in DARE.
19 studies (832 patients) examining cognitive-behavioural interventions, yielded an overall effect size of 0.63 (p<0.0001). The drop-out rate for these interventions was 5.6%, and 7.2% in the control groups.
The difference between effect sizes of cognitive-behavioural vs. pharmacological interventions was significant (p=0.05). 6 of 8 studies examining combined pharmacological and cognitive-behavioural interventions showed that there was no difference between imipramine plus cognitive-behavioural interventions and imipramine alone.An third systematic review focused on the effectiveness of cognitive behaviour therapy (CBT) as treatment for agoraphobic patients with panic attacks. This review included 35 studies with a total of 1317 subjects and was abstracted in DARE.
Both narrative review and meta-analysis was presented. CBT improved panic measures (21 studies), fear and avoidance measures (27 studies), and severity and intensity measures (16 studies). Results were inconsistent in general anxiety measures (19 studies): 17 studies reported improvement and 2 studies reported no statistical improvement. Also results on social anxiety measures (5 studies): were inconsistent. Four studies reported improvement and 1 study reported no statistical improvement.
In meta-analysis, Fear Questionnaire agoraphobia subscale was used (11 studies, 18 treatment arms). Patients on average moved from 3.88 to 1.70 standard deviations (SD) of the collegiate mean at post-treatment, and to 1.70 SD at follow-up.
The treatments that seem to be the most effective aim at reducing both the perceived danger and the fear of symptoms associated with panic attacks. These approaches generally reach very high success percentages in the treatment of panic disorder without agoraphobia. An overview presented 7 controlled studies in 6 different countries comparing Clark and Salkovskis’ version of CBT for panic with other treatments . In all of these studies, the specific CBT was superior to the wait list and to other treatments, including supportive therapy, applied relaxation (2 out of 3 studies) and imipramine. At the end of the treatment an average of 84% of the patients was panic free (range 74 – 94%) and results were well maintained at follow up (an average of 78% panic free).
A Cochrane review included 3 RCTs with a total of 293 participants with panic disorder. A 16-week behaviour therapy was used in two trials, and a 12-week cognitive-behaviour therapy intervention in the third. Alprazolam was used in two trials and diazepam in one trial. Duration of follow-up varied, ranging from 0 to 12 months. Two trials (n=166) provided data comparing combination with psychotherapy alone (both using behaviour therapy). No statistically significant differences were observed in response during the intervention (RR 1.25, 95%CI 0.78 to 2.03), at the end of the intervention (RR 0.78, 95%CI 0.45 to 1.35), or at the last follow-up time point, although the follow-up data suggested that the combination might be inferior to behaviour therapy alone (RR 0.62, 0.36 to 1.07). One trial (n=77) compared combination with a benzodiazepine alone. No differences were found in response during the intervention (RR 1.57, 95%CI 0.83 to 2.98). Although the combination appeared to be superior to the benzodiazepine alone at the end of treatment (RR 3.39, 95%CI 1.03 to 11.21) the finding was only borderline statistically significant, and no significant differences were observed at the 7-month follow-up (RR 2.31, 95%CI 0.79 to 6.74).
Comment: The quality of evidence is downgraded by imprecise results (limited study size for each comparison) and indirectness (differences in studied patients, trials recruited in-patients or patients at psychiatric clinics).