The effect of successful treatment on the emotional and physiological response to carbon dioxide inhalation in patients with panic disorder.
BACKGROUND
A number of studies have shown that patients with panic disorder are more likely to have panic attacks during carbon dioxide inhalation than are normal comparison subjects. Some studies have shown that antipanic medications can reduce the anxiogenic response to carbon dioxide, but none have shown if this is the case for cognitive behavioral therapy or if successful treatment reduces the respiratory physiologic response to carbon dioxide.


METHODS
Twenty-five patients with panic disorder and 13 normal comparison subjects underwent baseline testing with 5% and 7% carbon dioxide inhalation. The patients were then retested after at least 12 weeks of treatment with either antipanic medication or cognitive behavioral therapy. Comparison subjects were retested after a similar interval.


RESULTS
Successful treatment resulted in lower panic rates, and reduced anxiogenic response. Treatment had no effect, however, on the respiratory physiologic response.


CONCLUSIONS
There is dissociation in treatment response between the subjective and objective responses to carbon dioxide inhalation in panic disorder patients, with the former but not the latter showing positive change. We hypothesize that the strengthening of higher cortical control over subcortical fear-related structures, whether via medication or cognitive behavioral therapy treatment, results in less anxiety and fear in response to provoked symptoms reminiscent of naturally occurring panic.
Gorman
Jack M
JM
Department of Psychiatry and the Laboratory of Clinical Psychobiology, Mount Sinai School of Medicine, New York, NY 10029, USA. jack.gorman@mssm.edu
Martinez
Jose
J
Coplan
Jeremy D
JD
Kent
Justine
J
Kleber
Marc
M
D000280:Administration, Inhalation; D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D002245:Carbon Dioxide / Q000494:pharmacology / Q000627:therapeutic use*; D015928:Cognitive Behavioral Therapy / Q000379:methods; D004305:Dose-Response Relationship, Drug; D004644:Emotions / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D010147:Pain Measurement / Q000379:methods; D016584:Panic Disorder / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D010555:Personality Inventory; D011569:Psychiatric Status Rating Scales; D012119:Respiration / Q000187:drug effects; D012720:Severity of Illness Index
D000928:Antidepressive Agents; D002245:Carbon Dioxide