Emotional responding to hyperventilation as a predictor of agoraphobia status among individuals suffering from panic disorder.

Some data suggest that panic patients with extensive agoraphobia (PDA) display more intense respiratory distress during their panic attacks than Panic disorder (PD) patients. However, no studies have determined if PDA patients also show heightened sensitivity to a respiratory challenge compared to PD patients. The current study examined the differential emotional responding to hyperventilation among PDA patients, PD patients, and a non-clinical group with a history of panic attacks. Response to hyperventilation challenge did not distinguish non-clinical panickers from panic patients; however, behavioral tolerance to hyperventilation challenge significantly predicted agoraphobia status among panic disorder patients, even after controlling for demographic and clinical status variables.