Effect of dissociative experiences on drug treatment of panic disorder.

Background And Objective: Dissociative experiences are widespread among patients with panic disorder and have a negative impact on cognitive-behavioural therapy. In this study we aimed to investigate whether or not dissociative experiences affect response to drug treatment for panic disorder.

Methods: Thirty-five patients, 20 women and 15 men, with a mean age of 35.4 years and a diagnosis of panic disorder, were enrolled in the study. Paroxetine 20 mg/day was administered over 6 weeks. Patients were assessed on the Dissociative Experience Scale (DES) and Panic and Agoraphobia Scale (PAS) at the commencement of therapy, and on the PAS again after therapy.

Results: The average DES score was determined as 30.3. Agoraphobia was identified in 34.3% of patients. DES scores were higher in patients with agoraphobia than in those without agoraphobia. Agoraphobia scores were higher in patients with high DES scores. When patients were divided into those with low DES scores (< or =30) and those with high DES scores (>30), a decrease in PAS scores with treatment was observed in both groups, but the decrease was greater in those with low DES scores (18.8 +/- 6.8 vs 5.7 +/- 5.7 in the high-DES score group; Z = 4.486, p = 0.00000053). Similarly, while a decrease in PAS scores with treatment was observed both in patients with agoraphobia (p < 0.05) and in those without agoraphobia, PAS scores decreased more in non-agoraphobic patients (16.7 +/- 7.5 vs 4.8 +/- 6.6 in patients with agoraphobia; Z = 3.799, p = 0.000047). In addition, the decrease in PAS scores was significantly correlated with baseline DES score (beta = 0.706, T = 5.727, p = 0.0000022).

Conclusion: This study shows that dissociative experiences reduce the response to drug therapy in patients with panic disorder.