Altered autonomic stress reactivity and recovery in panic disorder during the Trier Social Stress Test.

Altered autonomic stress reactivity and recovery have been linked to reduced self-regulation and adverse health outcomes. Based on the autonomic flexibility-neurovisceral integration model, panic disorder (PD) may be associated with dysregulated autonomic control and reduced physiological flexibility. Therefore, the aim of this study was to compare heart rate (HR), the time-domain heart rate variability parameters SDNN and RMSSD, in individuals with PD and healthy controls during psychosocial stress induction. Thirty individuals with PD and thirty age- and gender-matched healthy controls underwent the Trier Social Stress Test (TSST). Before, during, and after the TSST, their HR, SDNN, and RMSSD were measured. Both groups showed the expected autonomic response to stress, reflected in increased HR and decreased HRV during the TSST, followed by recovery thereafter. Individuals with PD showed attenuated stress-related decreases in RMSSD (β = 0.018, p = .002) and SDNN (β = 0.011, p = .010), as well as slower recovery thereafter in RMSSD (β = -0.044, p = .002) and SDNN (β = -0.026, p = .024), whereas no group differences emerged for HR. These findings suggest altered autonomic stress reactivity and recovery in PD, consistent with reduced autonomic flexibility. Rather than indicating a specific directional deficit in vagal withdrawal alone, the results point to broader dysregulation of autonomic adaptation to psychosocial stress. Cardiac vagal control may play a mediating role for therapy outcome and efficacy in PD.