COMPARISON BETWEEN CENTRAL AND AUTOMATED PERIPHERAL BLOOD PRESSURE MEASUREMENT FOR EARLY DETECTION OF KIDNEY DYSFUNCTION IN HYPERTENSIVE PATIENTS

Abstract

Objective: To assess the difference of blood pressure measurements using central and automated peripheral blood pressure measurement (oscillometric) devices among patients with primary hypertension for early detection of kidney dysfunction and the validity of automated BP measurement device compared with non-invasive central BP measurement device for diagnosis of hypertension. Also, to link between parameters such as augmentation index and pulse wave velocity index and early kidney dysfunction markers. Design and method: The study is a case-comparative study that included 201 patients with primary hypertension (108 patients with chronic kidney disease and 93 patients without kidney disease). Exclusion criteria were patients presenting with secondary hypertension, diabetes mellitus (DM), end stage renal disease (ESRD) on regular dialysis, young patients below 40 and above 70 years old and patients with collagen diseases. All patients underwent blood pressure measurement by OMRON M2 and Mobil-O-Graph devices, kidney function assessment and abdominal ultrasonography. Results: Patients with chronic kidney disease were significantly older (60.02±9.1 vs. 55.33±8.5; P < 0.001), with longer duration of hypertension (7.56±5.9 vs. 6.05±5.8; P = 0.020) in comparison to those without chronic kidney disease. Automated peripheral measurement of systolic blood pressure, diastolic blood pressure and pulse pressure were significantly higher in comparison to central blood pressure. Patients with chronic kidney disease had significantly higher augmentation index (24.06±12.6 vs. 19.02±10.8; P < 0.001) and pulsed wave velocity (8.66±1.5 vs. 8.69±6.8; P = 0.004) in comparison to those without chronic kidney disease. Augmentation index had positive correlation with pulse wave velocity (r = 0.183, P = 0.005). There was negative correlation between both pulse wave velocity and augmentation index and estimated glomerular filtration rate (r = -0.318, P < 0.001), and (r = -0.236, P < 0.001), respectively. Hence, arterial stiffness parameters are good positive test for prediction of chronic kidney disease. Conclusions: There is a strong agreement between non-invasive centrally and automated peripherally measured blood pressure in diagnosis of hypertension. But non-invasive central measurements are preferred over automated measurements for early prediction and detection of renal impairment.