Psychophysiological assessment of stress reactivity and recovery in anxiety disorders

The present study aimed to examine changes in psychophysiological arousal from baseline to a stressor phase (reactivity) and from the stressor phase to a second resting phase (recovery) in patients with anxiety disorders. Fifty adult patients with DSM-5 anxiety disorders (panic disorder, generalized anxiety disorder, or social anxiety disorder) and 28 healthy control (HC) participants underwent psychophysiological monitoring including electrocardiogram, respiration rate, electrodermal activity, gastrocnemius electromyograph, and end-tidal CO2 for a 3-min resting phase, a 6-min mild stressor phase, and a 3-min recovery phase. Anxious patients then went on to receive naturalistic cognitive-behavioral therapy (CBT) in a specialty outpatient clinic. Results for the reactivity phase indicated that compared to HCs, patients with social anxiety disorder exhibited heightened psychophysiological reactivity while patients with panic disorder and generalized anxiety disorder exhibited attenuated reactivity. Results for physiological recovery (return to baseline after the stressor was withdrawn) were mixed, but provided some support for slower autonomic recovery in patients with generalized anxiety disorder and panic disorder compared to HCs. Participants with all anxiety disorders exhibited diminished change in high frequency heart rate variability compared to HCs. Generally, psychophysiological reactivity and recovery were not associated with CBT outcome, though exploratory analyses indicated that greater respiration rate reactivity and stronger respiration rate recovery were associated with better CBT outcomes in patients with panic disorder.