Daya Ram Haldwani, Asha Yadav, P. K. Rathore, O.P. Tandon
ABSTRACT
Background & Objectives: The central nervous system (CNS) is frequently affected by primary hypertension leading to features of motor, sensory and cognitive deficits. Brainstem auditory evoked potentials (BAEPs) may provide an early evidence of sensory dysfunction. Correlation of BAEPs with severity of blood pressure has not been studied much. In the present study, BAEPs were recorded in primary hypertensive patients and its correlation with mean arterial blood pressure (MAP) was carried out.
Materials and Methods: BAEPs were recorded from Cz-A1 & Cz-A2 scalp regions in 30 hypertensive subjects and in 30 normotensive controls. Absolute peak latencies and interpeak latencies of different waves were compared in both the groups by using unpaired student’s T test. Systolic, diastolic and mean arterial blood pressures were also compared between the groups. Bivariate correlation analysis was done to find out any correlation between mean blood pressure and different waves of BAEPs.
Results: Significant increase in peak latencies of wave I, IV & V was seen in hypertensive subjects as compared to controls. Significant correlation between mean arterial pressure and absolute peak latencies of BAEP waves I, IV, V and interpeak latencies I-V, III-V was found in hypertensive patients. The amplitude of wave I was found to be negatively correlated with MAP.
Conclusion: This study indicates that auditory brainstem conduction pathways get delayed in hypertensive subjects and latencies are positively correlated with mean arterial blood pressure (MABP). Blood pressure regulatory mechanisms in the brainstem may influence the generators of different waves of BAEPs.
Keywords: Brainstem auditory evoked potential (BAEP), mean arterial pressure (MAP), primary hypertension, correlation