Effect of "365 Breathing Technique" on Intraocular Pressure and Autonomic Functions in Patients With Glaucoma: A Randomized Controlled Trial

Precis:Patients with primary open angle glaucoma were advised to follow the "365 breathing technique" for 6 weeks in addition to their pharmacological glaucoma treatment. It helped to reduce intraocular pressure (IOP), stress biomarker-cortisol, and improve autonomic dysfunction.Objective:To study the effect of the "365 breathing technique" on IOP, autonomic functions, and stress biomarkers in patients with primary open angle glaucoma.Methods:In this randomized, controlled, interventional trial, after randomization, 40 patients in the intervention group followed "365 breathing" (three times a day, breathing rate: 6 cycles/min for 5 min) in addition to their pharmacological glaucoma treatment and 40 patients in the control group continued only with their pharmacological glaucoma treatment. IOP, serum cortisol, heart rate variability (HRV), and heart rate response to deep breathing test (DBT) were recorded at preintervention and 6 weeks postintervention.Results:The mean IOP, serum cortisol, parameters of the HRV test, and DBT were comparable between the two groups at baseline. At the 6-week follow-up, in the intervention group, mean IOP was significantly lower (16.09 +/- 2.24 vs 18.38 +/- 1.58 mm Hg, P = 0.03) and serum cortisol were significantly lower (13.20 +/- 3.11 vs 14.95 +/- 2.60 mcg/dL, P = 0.038) compared with the control group. In the HRV test, time domain analysis showed a significant difference in the root mean square of the successive difference between RR interval values between both groups at 6 weeks (P = 0.015) pointing towards higher postintervention parasympathetic activation in the intervention group. In frequency domain analysis (HRV test), the ratio of the low-frequency component to the high-frequency component was significantly lower in the intervention group at 6 weeks (1.65 vs 1.79, P = 0.019) indicating a shift in sympathovagal balance towards greater vagal modulation.There was a significant increase in delta heart rate (P = 0.019) and expiratory:inspiratory ratio (P = 0.011) in the intervention group at 6 weeks when compared with baseline values, indicating improved parasympathetic reactivity to DBT.Results:The mean IOP, serum cortisol, parameters of the HRV test, and DBT were comparable between the two groups at baseline. At the 6-week follow-up, in the intervention group, mean IOP was significantly lower (16.09 +/- 2.24 vs 18.38 +/- 1.58 mm Hg, P = 0.03) and serum cortisol were significantly lower (13.20 +/- 3.11 vs 14.95 +/- 2.60 mcg/dL, P = 0.038) compared with the control group. In the HRV test, time domain analysis showed a significant difference in the root mean square of the successive difference between RR interval values between both groups at 6 weeks (P = 0.015) pointing towards higher postintervention parasympathetic activation in the intervention group. In frequency domain analysis (HRV test), the ratio of the low-frequency component to the high-frequency component was significantly lower in the intervention group at 6 weeks (1.65 vs 1.79, P = 0.019) indicating a shift in sympathovagal balance towards greater vagal modulation.There was a significant increase in delta heart rate (P = 0.019) and expiratory:inspiratory ratio (P = 0.011) in the intervention group at 6 weeks when compared with baseline values, indicating improved parasympathetic reactivity to DBT.Conclusion:"365 breathing" technique can reduce IOP and serum cortisol, and improve autonomic dysfunction in patients with glaucoma.