Resistant Hypertension in Chronic Kidney Disease

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collaboration with the International Society of Hypertension suggests the goal of
treatment of hypertension to be <140/90 mmHg for patients with CKD without
albuminuria, and they have also acknowledged that it is recommended by some
experts that the goal of hypertension treatment be <130/80 mmHg for patients with
CKD with albuminuria [ 1 ].
Resistant hypertension (RHT) is a clinical situation in which, despite concomi-
tant intake of at least three antihypertensive drugs, one of these preferably being a
diuretic at full doses, blood pressure remains uncontrolled [ 2 ]. The American Heart
Association (AHA) [ 3 ] defines patients who need four or more drugs to control their
blood pressure as resistant.
Originally defined to identify a group of high-risk patients who may benefit
from specialized care, resistant hypertension included the evaluation and treat-
ment of the secondary causes of hypertension. JNC 7 defined resistant hyperten-
sion as the inability to achieve blood pressure that is lower than 140/90 mmHg
even with optimal doses of three of more hypertensive drugs including one diuretic
[ 4 ]. Resistant hypertension is defined by the 2008 AHA as uncontrolled hyperten-
sion despite treatment with at least three hypertensive drugs or controlled hyper-
tension with at least four drugs [ 3 ]. This definition of resistant hypertension does
not even attempt to make a distinction between resistant and pseudo-resistant
hypertension. Patients suffering from pseudo-resistant hypertension are those
individuals with elevated office BPs due to white-coat hypertension, improper BP
measurement, or medication nonadherence, which is not true resistant hyperten-
sion [ 5 , 6 ] (Table 15.1). To emphasize that pseudo-resistance hadn’t been excluded,
the term apparent resistant hypertension was adopted in epidemiological studies
for those patients with an office BP of >140/90 mmHg while taking ≥3 antihyper-
tensive medications [ 7 ]. After 24 h of ambulatory BP monitoring, pseudo-resis-
tance is excluded; the true resistance can be made from the apparent resistance
through the proper office BP measurement technique and confirmation of medica-
tion adherence. Due to this, true resistant hypertension is defined as a properly
measured office BP >140/90 mmHg with a mean 24-h ambulatory BP >130/80
mmHg in a patient confirmed to be taking ≥3 antihypertensive medications.
Excluding participants from the test population with pseudo-resistant hyperten-
sion is one of the challenges in establishing the prevalence of true resistant
hypertension.


Table 15.1 Causes of
“pseudo-resistant”
hypertension


Inaccurate measurement of BP
Inappropriate drug choices or doses
Nonadherence to prescribed therapy
White-coat effect

N. Keles et al.
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