Resistant Hypertension in Dialysis: Epidemiology, Diagnosis, and Management.

Apparent-treatment resistant hypertension (aTRH) is defined as an elevated blood pressure (BP), despite the use of ≥3 antihypertensive medications from different classes or the use of ≥4 antihypertensives regardless of BP levels. Among patients receiving maintenance hemodialysis or peritoneal dialysis, using this definition, the prevalence of aTRH is estimated to be between 18% and 42%. Due to the lack of a rigorous assessment of some common causes of pseudoresistance, the burden of true-resistant hypertension in the dialysis population remains unknown. What distinguishes apparent-treatment resistance from true resistance is white-coat hypertension and adherence to medications. Accordingly, the diagnostic work-up of a dialysis patient with aTRH includes the accurate determination of BP control status with the use of home or ambulatory BP monitoring and exclusion of non-adherence to the prescribed antihypertensive regimen. In a dialysis patient with inadequately controlled BP despite adherence to therapy with maximally tolerated doses of a β-blocker, a long-acting dihydropyridine calcium-channel-blocker and a renin-angiotensin-system inhibitor, volume-mediated hypertension is the most important treatable cause of resistance. In daily clinical practice, such patients are often managed with intensification of antihypertensive therapy. However, this therapeutic strategy is likely to fail, if volume overload is not adequately recognized or treated. Instead of increasing the number of prescribed BP-lowering medications, we recommend diet and dialysate restricted in sodium to facilitate achievement of dry weight. The achievement of dry weight is facilitated by an adequate time on dialysis of at least 4 hours for delivering an adequate dialysis dose. In this article, we review the epidemiology, diagnosis and management of resistant hypertension among patients on dialysis.