Resistant Hypertension in Chronic Kidney Disease

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Although the value of lifestyle interventions in patients already taking antihyper-
tensive drugs has not been widely examined, the current evidence, obtained firstly
in patients treated with one or two drugs, seems promising. Regular exercise alone
lowered DBP and led to regression of left ventricular hypertrophy (LVH) in a small
study of medicated African-American men with uncontrolled hypertension [ 35 ],
and the TONE study showed that in elderly patients receiving antihypertensive
monotherapy, sodium restriction and weight loss paved the way for improved BP
control [ 36 ]. Notably, there are limited data showing the effects of the DASH diet in
medicated hypertensive patients. In a study of 55 hypertensive patients treated with
an angiotensin receptor blocker (ARB), the DASH diet was related with a 5-mmHg
greater reduction in ambulatory SBP compared to patients taking the ARB with
their regular diet [ 37 ]. The ADAPT trial [ 38 ] was an Australian study of hyperten-
sive patients treated with one or two drugs in which an intervention designed to
promote consumption of a modified DASH diet gives way to a modest (4/2 mmHg),
but statistically important, decline in ambulatory BP and declined dependence on
antihypertensive medications. In the DEW-IT study [ 39 ], a 9-week “feeding” study
of 44 overweight adults on a single BP-lowering agent and the DASH diet coupled
with weight loss also resulted in significant BP reductions. Notably, lifestyle change
has not been correctly evaluated in patients with RHT.
Several small studies, however, put forward that modifications in diet and physi-
cal activity have the potential to lower BP substantially in these persons. For
instance, in a study of 12 subjects with RHT, 24-hour ambulatory BP was 23/9
mmHg lower on a 50 mmol/day (1150 mg/day) sodium diet compared to a 250
mmol/day (5750 mg/day) sodium diet [ 32 ]. In this study, however, the periods of
treatment were short (7 days), and all food was prepared in a clinical research center.
In the longer term and the absence of specially prepared meals, the similar results
may not be accomplished. In another small study, Dimeo et al. [ 34 ] checked the
value of physical activity in 50 patients with RHT who were randomized to thrice
every week treadmill exercise or a control condition; exercise decreased ambulatory
daytime BP by 6/3 mmHg. For that reason, preliminary evidence puts forward that
lifestyle changes may be effective in diminishing BP in RHT patients, but these
efforts required to be examined in more rigorous randomized clinical trials (RCTs.)


Public Policies for Prevention and Treatment of RHT

in Europe and the USA

A thorough consideration of public policy is vital to efforts to both prevent and treat
hypertension (Table 15.3). This is true not only in Europe, where the public sector
is largely responsible for financing health care; it is also the case in the USA, home
to an ever-increasing public tranche of costs since the 1960s’ implementation of
Medicare and Medicaid, growing to 45.6% by 2003, 48.1% in 2006, and predictions
of close to 50% [ 40 ]. Unfortunately, public funds for prevention do not account for
a large share of expenditure. Health data compiled by the Organisation for Economic


N. Keles et al.
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