Because HTN is very common in children with CKD and associated with target organ damage , monitoring of BP should be a routine part of clinical care. In turn, when elevated BP is identified, treatment should be aggressively pursued. In children with mild CKD (e.g., stage I–II) and a past history of BP measurements that are < 90th percentile, a BP assessment every 3–6 months is reasonable. In children with more advanced CKD (e.g., stage III–V), or a prior history of BP measurements that have exceeded the 90th percentile, more frequent monitoring is recommended. In view of the high prevalence of masked HTN in children with CKD, an ABPM study should be considered in any child with moderate-severe CKD or in any child with CKD regardless of casual BP readings with findings of LVH, increased cIMT, or proteinuria. While the optimal model for the use of ABPM remains to be determined, one possible plan in children with CKD is to obtain an ABPM every 1–2 years. Additional ABPM studies can be completed 1–2 months after a change in antihypertensive therapy, especially in children where the medication changes were made to address masked HTN .

The treatment of elevated BP is important in children with CKD to protect against the development or advancement of cardiovascular disease and the progressive loss of kidney function. Although prior guidelines [8, 34] have recommended that the target BP for children with CKD should be < 90th percentile, or < 130/80 mmHg, whichever is lower, more recent guidelines have suggested lower BP goals. The KDIGO Clinical Practice Guidelines for the Management of Blood Pressure in Chronic Kidney Disease published in 2012 [16] recommends that BP-lowering therapy in children with CKD be initiated when the BP exceeds the 90th percentile and suggests that the target BP is a SBP and DBP ≤50th percentile. Because some children with CKD, particularly those prone to salt and water loss (e.g., dysplasia), may be prone to hypotension, BP targets should be individualized and more conventional BP targets may be appropriate. The rationale for lower BP goals stem primarily from the results of the ESCAPE trial [26]. This landmark study randomized 385 children with CKD to either intensified BP control or conventional BP control. All children received the angiotensin-converting enzyme (ACE) inhibitor, ramapril, at a dose of 6 mg/m² and additional antihypertensive agents (excluding drugs that were antagonist of the RAAS) were prescribed to achieve the target BP. A 24-h mean arterial pressure below the 50th percentile was the BP target for the intensified group, whereas the BP target for the conventional group was a 24-h mean arterial pressure between the 50th and 90th percentile. After 5 years, the number of children who had a > 50 % decline in the GFR or reached end-stage renal disease was significantly less in children who were randomized to the intensified BP group. There was no difference in the type or incidence of adverse events and the benefit of improved outcome persisted despite a loss of the effect on a reduction in the urinary protein excretion during the longitudinal follow-up.

Achieving BP goals often requires lifestyle modifications, specifically sodium restriction, and antihypertensive medications. While it is unlikely that a child with CKD will achieve their target BP solely with lifestyle modifications, these efforts should not be ignored, as the modifications may enhance the effect of many antihypertensive drugs and may help decrease the prevalence of other risk factors for cardiovascular disease . Nonpharmacologic treatment of HTN encompasses increased exercise and decreased sedentary time, weight loss in overweight children, stress reduction, incorporation of a Dietary Approaches to Stop Hypertension (DASH)-type diet, and sodium restriction. In children with CKD, dietary modifications may be challenging, or not possible, due to the requirement to limit potassium and phosphorus intake and should be implemented after consultation with a knowledgeable dietitian [35]. Likewise, sodium restriction may be contraindicated in children with diagnoses associated with urinary salt and water loss.

Almost all children with HTN complicating CKD require antihypertensive medications and often require multiple medications to achieve BP goals [17]. While the choice of the antihypertensive agent depends in part on whether the patient displays proteinuria, ACE inhibitors or angiotensin receptor blockers (ARBs) are the preferred agents in children with CKD as shown in Fig. 17.1. These drugs are preferred because of their ability to safely and effectively lower BP in adults and children with CKD and their benefit in preserving kidney function through anti-proteinuric, anti-fibrotic, and anti-inflammatory properties. The recommendation for the use of ACE inhibitors and ARBs is supported by the findings of the CKiD study where children who received ACE inhibitors or ARBs were less likely to have LVH [21] and more likely to have controlled BP [11] compared to children with CKD receiving other classes of antihypertensive agents. The BP-lowering effectiveness of ACE inhibitors was also observed in the ESCAPE study [17] where more than 50 % of children in the standard BP control group (target mean BP 50–95th percentile) were able to achieve BP control solely with aggressive dosing of the ACE inhibitor, ramapril (6 mg/m²). When proteinuria is absent or an ACE inhibitor/ARB is contraindicated, a long-acting dihydropyridine calcium channel blocker (e.g., amlodipine) can be considered for initial therapy. In children with CKD, especially those with edema, diuretics may be helpful in BP control . Thiazide-like diuretics can be used when the GFR is more than 30–40 ml/min/1.73 m² but are not effective in children with a lower GFR. Due to a prolonged duration of action, chlorthalidone may provide improved BP control and cardiovascular risk reduction when compared to other thiazide-like diuretics [36, 37]. In children with more advanced CKD, loop diuretics may be required. There are no clear guidelines on the preference or order of additional antihypertensive drugs that can be added to the regimen after maximizing combination therapy with ACE/ARB, calcium channel blockers, and diuretics. In view of the impressive BP-lowering results in adults with resistant HTN receiving mineralocorticoid receptor antagonist [38], a trial of an aldosterone antagonist (e.g., spironolactone, eplerenone) can be considered in those patients with good control of potassium homeostasis. Other antihypertensive drugs such as combined alpha/beta blockers, vasodilators, centrally acting agents, and alpha blockers can be added as necessary in children with CKD who have resistant HTN. Suggested oral doses for common antihypertensive medications are displayed in Table 17.2. Treatment of resistant HTN with renal denervation and baroreflex activation remain experimental at this time.