Chapter 11 Hypertension
Defi nition of CKD
CKD is defi ned as kidney damage, as confi rmed by
kidney biopsy or markers of damage, or glomerular
fi ltration rate (GFR) <60 mL/min/1.73 m^2 for ≥ 3
months. Using this defi nition the Third National
Health and Nutrition Examination Survey (NHANES
III) database and the US Renal Data System (USRDS)
estimates that approximately 11% of adults in the
United States have CKD.
Hypertension as a risk factor for
CKD progression
There is a strong, consistent relationship of higher
levels of blood pressure to faster kidney disease pro-
gression. In part, this may be due to deleterious effects
of higher intra-glomerular pressure (PGC) which
results in an elevated single nephron GFR, which in
the short term may lead to stabilization or even
increased GFR, but in the long term is followed by
proteinuria, glomerular sclerosis, and kidney failure.
Hypertension as a consequence of CKD
Hypertension is a common complication of CKD,
which increases the risk for the two main outcomes
of CKD: loss of kidney function sometimes leading to
kidney failure, and cardiovascular disease (CVD),
both associated with increased mortality. Appropriate
evaluation and management of hypertension and use
of antihypertensive agents in CKD offers the oppor-
tunity to slow the progression of kidney disease and
reduce the risk of CV. A GFR of <60 mL/min/1.73 m^2
or microalbuminuria (both criteria for the defi nition
of CKD) are independent risk factors for CVD, and
the designation of CKD as a “compelling indication”
for antihypertensive therapy at a lower BP threshold
with a lower BP target (<130/80 mm Hg).
Lifestyle modifi cations
Dietary and other therapeutic lifestyle modifi cations
are recommended as part of a comprehensive strat-
egy to lower blood pressure and reduce CVD risk in
CKD. Dietary sodium intake of less than 2.4 g/d (less
than 100 mmol/d) should be recommended in most
adults with CKD and hypertension. Other dietary
recommendations for adults should be modifi ed
according to the stage of CKD, with the DASH diet
modifi ed with protein intake 0.6 to 08 g/kg/d, phos-
phorus 0.8–1.0 g/d and potassium 2–4 g/d for for
Stage 3–4 CKD. Other lifestyle modifi cations include
weight maintenance if BMI <25 kg/m^2 , weight loss
if overweight or obese, moderation of alcohol intake
and smoking cessation (Level of Evidence A).
Pharmacologic therapy
All antihypertensive agents can be used to lower
blood pressure in CKD. Multi-drug regimens will be
necessary in most patients with CKD to achieve
therapeutic goals. Patients with specifi c causes of
kidney disease and CVD will benefi t from specifi c
classes of agents. Target BP for CVD risk reduction
in CKD should be <130/80 mm Hg.
ACE inhibitors and ARBs are the “preferred agents
for diabetic kidney disease and nondiabetic kidney
disease with spot urine total protein to creatinine
ratio of ≥200 mg/g (Level of Evidence A). They should
be used at moderate to high doses, as used in clinical
trials. Patients treated with ACE inhibitors or ARBs
should be monitored for hypotension, decreased GFR
and hyperkalemia. The fi rst agent to be added there-
after should be a diuretic. Patients treated with ACE
inhibitors or ARBs should be monitored for hypoten-
sion, decreased GFR, and hyperkalemia. In most
patients the ACE inhibitor or ARB can be continued
if (a) the GFR decline over four months is <30% from
the baseline value; (b) serum potassium is <5.5 mEq/
L (Level of Evidence B). Other drugs which may be
used are CCBs or β-blockers.
Thiazide diuretics given once a day are recom-
mended in patients with a GFR ≥30 mL/min/1.73 m^2
and loop diuretics in patients with a GFR <30 mL/
min/1.73^2. Loop diuretics may be given in combina-
tion with thiazide diuretics for patients with ECF
volume expansion and edema. Potassium-sparing
diuretics should be used with caution in patients with
a GFR <30 mL/min/1.73 m^2 , in patients receiving
concomitant therapy with ACE inhibitors or ARBs
and in patients with additional risk factors for hyper-
kalemia. Patients treated with diuretics should be
monitored for volume depletion, manifested by
hypotension or decreased GFR, hypokalemia or other
electrolyte abnormalities (Level of Evidence A).
Endocrine disease and pregnancy
The National Kidncy Foundation guidelines also
include recommendations for the management of
hypertension in patients with endocrine disease and
pregnancy. These are summarized in Box 11.1.