Physiological Changes During Carbon Dioxide Inhalation in Patients With Panic Disorder, Major Depression, and Premenstrual Dysphoric Disorder

Abstract

Although CO(2) breathing causes a higher rate of panic attacks in patients with PD than other groups (except PMDD), the physiological features of a panic attack appear similar across groups. Once a panic attack is triggered, minute ventilation and respiratory rate increase regardless of whether the subject carries a PD diagnosis. These findings are compatible with preclinical fear conditioning models of anxiogenesis.