CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 1, January/February 2011
AFRICA
45
Opinions in Hypertension Management
Improving hypertension control in patients at cardiovascular risk:
the case for telmisartan-based therapy
Strategies to improve hypertension control
are clearly warranted in light of the
frequently expressed view that only 50%
of treated hypertensive patients are able
to meet their target blood pressure levels.
While data from the USA has shown
improved control over recent years (Table
1), a study in 2008 of SouthAfrican gener-
al medical practice (private sector) showed
that 61% of patients reached their target
blood pressure levels. If the even-stricter
target blood pressure levels of 130/80
mmHg were applied to those patients
with co-morbidities who needed to reach
and maintain these lower levels, only 40%
of patients were successfully treated.
1
In primary-care, public-sector facili-
ties in South Africa, special efforts to
improve hypertension management have
shown that 68% of patients treated for
their hypertension can achieve their
targeted blood pressure levels.
2
Without
these intensive programmes, however,
hypertension control in the South African
public sector is likely to be much less
effective and lower than in the well-
serviced private sector.
Reducing the cardiovascular and renal
consequences of hypertension is depend-
ent on sustained, long-term blood pressure
control, implying that patient compliance
is also a key factor for success. The physi-
cian’s choice of effective therapy will take
this aspect fully into account and he/she
will adopt approaches that will sustain
patient compliance.
Modern therapeutic agents that block
the renin–angiotensin–aldosterone system
(RAAS) and protect target organs with-
out causing compliance-reducing symp-
toms should be the first choice in at-risk
patients with hypertension.
Achieving sustained blood
pressure control
Once-a-day dosage
Patients typically prefer to take their
medication in the morning as part of
their everyday routine. Compliance is
improved by once-daily medication and
physicians are keen to ensure that the
prescribed antihypertensive medication
meets the criteria of full 24-hour control
and provides cover for the early morning
rise in blood pressure. This rise in blood
pressure is due to both orthostatic chang-
es and the circadian rhythm of the RAAS
system. It is also linked to an increased
risk of cardiovascular events during the
early morning hours.
3
Accurate assessment of blood pressure
control is determined by self-measure-
ment of blood pressure or by automated
ambulatory 24-hour measuring devices.
The MICARDIS Community Access
Trial of Telmisartan in the primary-care
setting (MICCAT-2)
4
study showed that
telmisartan alone or in combination with
HCTZ produced significant reductions in
blood pressure, which extended into both
day and night time. Telmisartan reduced
systolic and diastolic blood pressure
(SBP/DBP) by 17.2/10.1 mmHg in the
first four hours post-awakening in patients
whose early morning blood pressure rose
more than 30 mmHg prior to therapy.
ARB efficacy versus ACE
inhibitors
ARBs are a good choice for hypertensive
patients with the metabolic syndrome
(associated obesity) and there are compel-
ling indications for their use in post-
myocardial infarction, left ventricular
hypertrophy, chronic kidney disease, type
2 diabetes with microalbuminuria or albu-
minuria, for ACE-intolerant patients and
for the secondary prevention of stroke.
5
The evidence for therapeutic equiva-
lence of telmisartan versus ACE inhibi-
tors resides in direct major compari-
son trials with ramipril and perindopril.
In the PRISMA-1 study (Prospective
Randomised Investigation of the Safety
and efficacy of MICARDIS versus rami-
pril) also conducted in South Africa,
1 613 hypertensive patients were treated
either with temisartan 40–80 mg or rami-
pril (uptitrated from 2.5–10 mg) in the
morning, and resulting blood pressure
was evaluated using ambulatory blood
pressure monitoring.
Telmisartan provided more effective
blood pressure lowering in this study
and was particularly more efficient in
the last six hours of the 24-hour dosing
interval. Similar results were obtained
by PRISM-2, which was conducted in
the USA and Canada. A pooled analy-
sis of both trials also showed a greater
blood pressure lowering with telmisartan
(–14.1/–9.6 vs –11.1/–7.2 mmHg).
6
In a
double-blind study of telmisartan 80 mg
versus perindopril 4 mg, similar results
in blood pressure lowering were obtained
but telmisartan resulted in lower diastolic
blood pressures over the last eight hours
of therapy. Other studies versus lisinopril
produced similar results.
Telmisartan is the only ARB that has
demonstrated therapeutic equivalence to
the ACE inhibitor ramipril in hyperten-
sive patients at increased vascular risk.
The patient population in this study
TABLE 1. TRENDS IN HYPERTENSION PREVALENCE, AWARENESS,
TREATMENTAND CONTROL IN THE USA*
1988–1991 1991–1994 1999–2000 2007–2008
Hypertension prevalence (%)
25.0
25.0
28.7
29.0
Awareness (%)
69.2
67.8
68.9
80.7
Treatment (%)
52.4
52.0
58.4
72.5
Control
Among those treated (%)
46.9
43.6
53.1
69.1
Among all with hypertension (%)
24.6
22.7
31.0
50.1
*Data derived from Jajjar and Kotchen, copyright 2003, American Medical Association and
Egan
et al
., copyright 2010, American Medical Association.
