267and 42% in second group (P < 0.01); interdialytic weight gain was significantly
lower in Centre A (2.29 ± 0.83 kg versus 3.31 ± 1.12 kg, P < 0.001). Mean systolic
and diastolic BPs were similar in the two groups. However, first group had lower left
ventricular (LV) mass index and cardiac hypertrophy [ 53 ].
In another prospective study, the effects of strict salt control on blood pressure
and cardiac condition in end-stage renal disease were investigated. A total of 12
peritoneal dialysis (PD) and 15 prevalent hemodialysis (HD) patients were enrolled.
All patients with either PD or HD were allocated to intervention of strict salt restric-
tion according to basal hydration state of empty abdomen in PD and midweek pre-
dialysis HD which were estimated by body composition monitor (BCM) and
echocardiography. Systolic BP decreased in PD and HD from 133.1 ± 28 and
147.3 ± 28.5 to 114.8 ± 16.5 and 119.3 ± 12.1 mmHg, respectively (P < 0.00) [ 54 ].
Despite these studies showing the beneficial effect of sodium restriction, there
are no large-scale, long-term prospective studies investigating the effect of strict
sodium restriction on cardiovascular outcomes.
As seen, there are very few studies regarding sodium, CKD, and HT, especially
resistant HT. It is obvious that more prospective, randomized studies are needed to
define the role of salt restriction on BP and cardiovascular outcomes in CKD
patients. The following chapter will focus on the management of RHT in CKD
especially focusing on salt restriction.
Management of Salt Restriction
As suggested most patients with HT and CKD are salt sensitive. Sodium intake in
CKD populations is generally high, and often above population average. Recent
evidence suggests that independent of BP, high salt induces structural and func-
tional deterioration in vessels. Additionally, moderately lower sodium intake in
CKD patients is associated with substantially better long-term outcome of RAAS
blockage, in diabetic and nondiabetic CKD, related to better effects of RAAS block-
age on proteinuria independent of BP [ 55 , 56 ].
Therefore, educating patients with CKD on a low salt diet is critical to achieving
BP control while maintaining a simple BP medication regimen. However, it should
be remembered that reducing salt intake is a hard task to achieve. Effectively reduc-
ing salt intake is not achieved even under supervision [ 57 ]. Due to low palatability
of low sodium diets, convenience and lack of knowledge regarding the benefits of
low sodium diet [ 58 ].
In 2005, the US Department of Health and Human Services recommended that
adults consume no more than 2300 mg of sodium per day and those patients in speci-
fied subgroups (including persons with CKD) consume no more than 1500 mg/d.
However, it was criticized that the evidence is not strong enough to indicate that
these subgroups should be treated differently than the general US population [ 59 ].
In a double-blind placebo-controlled crossover trial, 20 hypertensive adults
with stage 3–4 CKD were randomized to a low sodium diet by dietary education
16 Treatment of Hypertension in Light of the New Guidelines: Salt Intake