Effects of Slow Breathing Exercises on Cardiac Autonomic Functions in Anxiety Disorder—A Randomised Control Trial

Background: Anxiety disorders are commonly associated with a higher risk of fatal cardiovascular diseases (CVD). Anxiety disorders lead to dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, weakening key neuronal components of the autonomic nervous system (ANS) involved in cardiovascular functions, and increasing cardiovascular risk. Purpose: Impaired ANS activity, as reduced parasympathetic tone, is strongly associated with increased risk of CVD in anxiety disorders. Slow pranayama influences the ANS by activating the parasympathetic tone and deactivating the sympathetic tone in healthy volunteers and various diseased conditions. Therefore, we aimed to study the effects of slow pranayama and savasana on cardiac autonomic function tests in anxiety disorder patients. Methods: Anxiety disorder patients (N = 140) aged 18–40 years attending the psychiatry OPD at JIPMER were randomly assigned to a pranayama group and a control group. The pranayama group practiced slow pranayama and savasana for 8 weeks along with routine psychiatric care; the control group continued routine psychiatric care only. Outcome measures included heart rate variability (HRV), baroreflex sensitivity (BRS), 30:15 ratio during lying to standing, E:I ratio during deep breathing, and ΔDBP during isometric handgrip, assessed before and after the intervention. Results: After 8 weeks in the pranayama group, HRV parameters improved toward the parasympathetic domain; there was a significant increase in parasympathetic reactivity, a decrease in sympathetic reactivity, and significant improvement in BRS. Conclusion: Slow pranayama and savasana practice in anxiety disorder patients, as an adjunct to routine psychiatric care, effectively improves cardiac autonomic function with a shift toward parasympathetic predominance, with significant improvements in cardiovascular parameters. Slow pranayama with savasana may be incorporated into routine care to enhance cardiovascular health.

Natarajan Kavitha, Pravati Pal, Gopal Krushna Pal, Balaji Bharadwaj, Nivedita Nanda