Heart rate variability and generalized anxiety disorder during laboratory-induced worry and aversive imagery

Abstract

Background: To date only a few published studies have examined the effect of disorder-relevant stressors on heart rate variability (HRV) in participants meeting a clinical diagnosis of GAD, with conflicting results. The primary aim of this study was to determine if GAD is associated with lower HRV at rest, and whether vagal regulation during task varies by type (i.e., baseline, anticipation, imagery, or worry).

Methods: This study investigated resting cardiac vagal tone and vagal regulation in a sample of 40 participants with or without a validated diagnosis of generalized anxiety disorder (GAD). High-frequency heart rate variability (HF-HRV) was used to index cardiac vagal activity.

Results: GAD was associated with vagal withdrawal during both imagery and worry inductions, but no group differences in resting vagal tone or worry were observed.

Limitations: Methodological limitations include inherent limits to generalizability of laboratory-based findings; specifically worry induction and cardiac reactivity to lab-based stressors.

Conclusions: The results support the notion that GAD is associated with vagal withdrawal during active bouts of idiographic worry and imagery, and question the assumption that GAD is associated with low resting vagal tone. In light of polyvagal theory these findings provide additional support for the presence of emotion regulation deficits in GAD, and identify specific ANS processes that underlie GAD.

Keywords: Generalized anxiety disorder; Heart rate; Parasympathetic nervous system; Worry.