1PG Student, Dept. of Physiology, Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences, Rohtak, Haryana
2Senior Professor & Head, Dept. of Physiology, Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences, Rohtak, Haryana
Open angle glaucoma is a chronic, slowly progressive optic neuropathy characterised by progressive visual field loss. At systemic level; hypertension, hypotension leading to reduced ocular blood flow (OBF), vasospasm, oxidative stress and cardiovascular disease history are associated with glaucoma. Various studies suggest a relation between Open angle glaucoma (OAG) and autonomic dysfunction, yet the exact mechanism is still unclear. Heart rate variability (HRV) and a provocative cardiac stress test can provide an easy, non-invasive and indirect assessment of the autonomic control of the heart.
The present study consists of 20 patients with Primary Open angle Glaucoma (group II) and 20 age & sex matched healthy controls (group I). Frequency domain analysis of HRV at rest and during Handgrip testing was analysed.
On immediate release of handgrip patients with POAG depicted a significant raised Low frequency variables LF (nu) (73.39± 4.04), (p < 0.000) and LF/HF ratio (2.79±0.17), (p < 0.000). On the other hand there is a step decrease in high frequency variable HF (nu) (32.04±1.83) in group II (p = 0.002). The decrease in HF (nu) (38.40±8.07), (p < 0.000) with high LF/HF (1.55±0.28), (p<0.000) in group II remained significant during recovery period.
The study thus concluded sympathetic overdrive in response to stress and low parasympathetic activity during recovery period suggestive of impaired autonomic activity in Primary Open angle Glaucoma.
Stress Test, Autonomic Dysfunction, Primary Open Angle Glaucoma, Auto Regulation, Heart Rate Variability
