Hypertension in Chronic Kidney Disease and End-Stage Kidney Disease

1

What is the prevalence of hypertension in chronic kidney disease?

Hypertension is common in patients with chronic kidney disease (CKD). In the 2015–16 National Health and Nutrition Examination survey, 61.4% of patients with CKD had hypertension; 37.4% of patients had controlled blood pressure (BP).

2

How should BP be measured in the office in patients with CKD?

BP measurement in the office should follow standard guidelines for accuracy including avoidance of caffeine, exercise, and smoking for at least 30 minutes prior to measurement, appropriate positioning, and using the proper sized cuff. Two or more readings should be averaged for each visit. Automated oscillometric BP monitors are preferred.

3

What is the role of ambulatory blood pressure monitoring and home BP monitoring in CKD?

Indications for ambulatory blood pressure monitoring (ABPM) include:

• To evaluate white coat or masked hypertension

• To monitor antihypertensive medication efficacy in treated patients

• To evaluate postural, postprandial, and medication-induced hypotension

• To assess hypotension from autonomic dysfunction

Home BP monitoring is less cumbersome than ABPM and is a valuable adjunct in the management of hypertension. Patient education regarding proper technique of BP measurement and periodic assessment of home BP devices for accuracy is essential. An average of two morning and two nightly readings over 7 days should be used to assess BP control.

4

What is the pathophysiology of hypertension in CKD?

The pathophysiology of hypertension in CKD is complex and multifactorial. Reduction in the glomerular filtration rate (GFR) leads to sodium and water retention. This, along with endothelial dysfunction, nitric oxide inactivation, and activation of intrarenal renin-angiotensin-aldosterone system (RAAS) leads to central sympathetic activation, vasoconstriction, and increased peripheral resistance, eventually resulting in elevated BP ( Fig. 17.1 ).

5

What are the consequences of untreated hypertension in patients with CKD?

Hypertension contributes to ongoing decline in kidney function regardless of the underlying cause of CKD. Normally, afferent arteriolar contraction in response to elevated BP protects the glomerular capillaries from elevated systemic pressures. Chronically elevated systemic arterial pressures impair the ability of afferent arterioles to respond to systemic BP, leading to higher intraglomerular pressure, nephrosclerosis, and progressive loss of kidney function.

Hypertension also adds to the high risk of cardiovascular disease in patients with CKD.

6

What is the target BP in CKD?

The 2017 American College of Cardiology/American Heart Association guidelines recommend a target BP less than 130/80 mm Hg for all CKD patients with hypertension. This has been shown to reduce risk of cardiovascular events and mortality, although, interestingly, it does not reduce the rate of progression of CKD. Of note, the 2018 European Society of Cardiology/European Society of Hypertension guidelines recommend lowering BP to less than 140/90 mm Hg, with systolic BP in the 130- to 139-mm Hg range.