Abstract
Background: Patients with chronic kidney disease (CKD) suffer with both autonomic and cardiac dysfunction. Reports analyzing the correlation between autonomic and vascular dysfunction are fairly accurate.

Aims and Objective: We correlated vascular sympathetic reactivity to isometric handgrip exercise and vascular stiffness in nondiabetic pre dialysis CKD patients noninvasively.

Materials and Methods: A total of 52 participants. 28 nondiabetic CKD and 24 normal, were recruited for this study. Blood pressure was measured by oscillometry and vascular sympathetic reactivity. Absolute rise in diastolic blood pressure (ARDBP) was assessed using isometric handgrip test. Pulse wave velocities (PWV) were recorded using automatic waveform analyzer and pressure-standardized elastic vascular resistance (EVR) was derived from it. Carotid–femoral PWV (cf-PWV) >12 m/s was considered as vascular dysfunction. Serum nitric oxide (NO) and malondialdehyde (MDA) were also measured.

Results: The patients had lower values of NO and higher values of MDA than the controls. Isometric handgrip exercise, the test performed to detect sympathovagal imbalance suggesting presence of autonomic dysfunction, was observed in 80% of patients vs. 20% of controls, whereas arterial dysfunction was observed only in 34% of patients vs. 14% controls. No correlation was observed between autonomic and vascular dysfunction (r = 0.13, P > 0.05).

Conclusion: Our study results demonstrate that nondiabetic CKD patients had increased central artery stiffness (cf-PWV) as compared to controls. It was also observed that reduced vascular compliance was associated with autonomic imbalance, increased oxidative stress, and decreased NO bioavailability. However, no correlation was observed between autonomic and vascular dysfunction. Our study confirms that the multiple complex pathogenesis mechanisms that cause vascular dysfunction coexist in our patient group.

Key words: Chronic Kidney Disease; Isometric Hand Grip; Carotid–Femoral Pulse Wave Velocity; Malondialdehyde; Oxidative Stress; Pressure Standardized Elastic Vascular Resistance