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agreement between ABPM and HBPM results. In another study of 73 subjects with
RH, HBPM was found to be a reliable alternative to ABPM in the diagnosis of true
RH [ 16 ]. Although HBPM cannot provide blood pressure data during sleep, never-
theless it allows the detection of white-coat hypertension, masked hypertension, and
blood pressure pattern during the day and the awake night [ 17 ].
In summary, general practitioners should monitor antihypertensive therapy pref-
erentially with multiple blood pressure measurements. Office blood pressure mea-
surements must be fully in compliance with best practice guidelines. GPs should be
knowledgeable about advantage and disadvantages of ABPM and HBPM tech-
niques. They should be aware of the high prevalence of pseudoresistant hyperten-
sion (mainly owing to white-coat RH) and the ability of ABPM and HBPM to
exclude pseudoresistance before undertaking further costly investigations for the
true causes of RH.
Important Factors Related to Resistance and the Role
of the GP
Nonadherence
Once the true nature of RH is confirmed, GP should investigate whether the nonad-
herence is at play in the RH patient. Nonadherence to prescribed medications is
more common in primary care compared to tertiary centers [ 18 ]. Several factors are
related to nonadherence such as adverse effects of the drugs, pill number and com-
plexity of the antihypertensive regimen, education level, and cultural issues. Number
of the pills is particularly relevant in RH because as the definition implies, these
patients simultaneously use at least three medications from different classes. A
study by Jung et al. [ 19 ] showed that out of 108 patients with RH, 40 patients were
nonadherent based on toxicological urine analysis.
Nonadherence may be a more challenging problem in CKD population because
of increased number of the elderly patients, polypharmacy, and decreased cognitive
function. Thus, GPs should look for possible adherence problems when they
encounter with a CKD patient who has RH. Education, prescribing combined phar-
maceutical forms (two drugs in one pill), frequent review of possible adverse effects
of medications, and close follow-up may help reducing nonadherence.
Salt Intake
Salt restriction can reduce blood pressure both in the hypertensive and normotensive
subjects. This blood pressure reducing capacity is particularly prominent in patients
with RH [ 20 ]. CKD, particularly in advanced stages, is a salt-retaining disease.
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