How to diagnose hypertension in hemodialysis patients?

An accurate measurement of BP is essential for the diagnosis and treatment of hypertension in any hypertensive patient. Although hypertension is a big public health burden in hemodialysis patients and is characterized by elevated systolic and pulse pressure, assessment of blood pressure in these patients is often difficult. Some problems unique in this hypertensive population include interdialytic weight gain, occurrence of sleep-apnea and consequent nocturnal hypertension, and the inability to take BP in both arms in patients who have hemodialysis angioaccess in the arm. The problems of accurate assessment of BP are compounded by the lack of standardized BP measurements and the occurrence of white coat effect in about 1 in 5 patients. Precise measurement of BP in hemodialysis patients requires interdialytic ambulatory BP monitoring. However, when ambulatory BP monitoring is not possible, BP obtained in the dialysis unit can be used in a qualitative sense for prediction of hypertension in these patients. A 2-week averaged predialysis BP of >150/85 mmHg or a postdialysis BP of >130/75 mmHg has at least 80% sensitivity in diagnosing hypertension. Specificity of at least 80% can be achieved if predialysis BP of >160/90 mmHg or postdialysis BP of >140/80 mmHg are used. However, poor agreement between HD unit BPs and ABPs precludes their use for the precise prediction of BP. Improving the measurement technique in the dialysis unit, averaging multiple BP, using a 20 min postdialysis reading, or home BP monitoring can improve BP determination when interdialytic BP monitoring is not possible.