CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 3, April 2013
98
AFRICA
Treating hypertension in the elderly, even white-coat
hypertension, is essential
Hypertension treatment in the very elderly
over the age of 80 years is beneficial
and is associated with reduced risk of
death from stroke, death from any cause
and heart failure.
1
The results from the
extensive Hypertension in the Very
Elderly Trial (HYVET) using indapamide
sustained release 1.5 mg and either 2 or
4 mg perindopril daily provides tangible
evidence for this approach.
Recently, the Ambulatory Blood
Pressure (ABP) results were published
of a subgroup of 284 of the almost 4 000
patients who participated in the initial
HYVET study by the investigators, headed
by Prof Christopher Bulpitt, emeritus
professor of Geriatric and Cardiovascular
Medicine, Imperial College, London.
2
HYVET was a pivotal study in the
super-elderly and is still the only large,
double-blind, randomised trial to address
the dilemma of treating hypertension in
the over-80-year-old patient. It was a very
difficult trial to perform and took some
10 years to recruit and randomise 3 845
patients. However, the results were clear
cut and resolved the clinical uncertainty
of treating these very elderly patients.
Further analysis of the extensive dataset
now provides further clinical insights of
importance.
In HYVET, the goal blood pressure
was less than 150/80 mmHg and this
approach was associated with a 21%
reduction in total mortality, a 30%
reduction in stroke and a 34% reduction
in any cardiovascular event. These results
apply to the trial participants who were
over 80 years of age with an untreated
systolic clinic-measured blood pressure
(CBP) of 160–199 mHg and a CBP
difference of 15/6 mmHg between the
placebo and the actively treated group
after two years (Figs 1-3).
The population of HYVET was quite
healthy elderly people; only 12% had had
previous coronary vascular disease and
7% had diabetes. However, more than
90% were known to be hypertensive, of
which approximately one-third had not
previously been treated.
The evidence from the ambulatory
study highlights the fact that the
beneficial blood pressure-lowering action
of the indapamide-based therapy with
added perindopril was effective and safe
over the 24-hour period. This ambulatory
blood pressure (ABP) study has also
provided valuable insights on the value of
treating ‘white-coat hypertension’ in the
very elderly, as it has shown that between
40 and 60% of eligible participants in
the main study may have had white-coat
hypertension. This is based on the ABP
finding that at study entry, CBP exceeded
the morning ABP by 32/10 mmHg in the
subgroup examined, indicating that 50%
of participants fulfilled the established
criteria for WCH.
White-coat hypertension is said to be
present when the CBP is above normal
but the ABP is judged to be normal. It
has also long been recognised that the
CBP–ABP differences increase with age
such that the ABP falls with age relative
to CBP.
In HYVET, with such a high number of
patients with WCH, it is unlikely that the
study would have produced such positive
results if the WCH had been ignored, as is
currently recommended by hypertension
treatment guidelines. The observation that
the presence of white-coat hypertension
in the very elderly represents an ‘at-risk’
population warrants further investigation.
1.
Beckett NS,
et al
. Treatment of hyperten-
sion in patients 80 years of age or older.
N
Engl J Med
2008; 358. Advance publication
10.1056/NejMoa0801369.
2.
Bulpitt CJ, Beckett N, Peters R, Staessen
JA,
et al.
Does white coat hypertension
require treatment over age 80?: Results
of the Hypertension in the Very Elderly
Trial Ambulatory Blood Pressure side
project. Hypertension 2012 published online
November 19, 2012.
Fig. 1. All stroke (30% reduction).
8
7
6
5
4
3
2
1
0
0
1
2
3
4
No. of events per 100 patients
Placebo Indapamide SR
±
perinodpril
Follow up (year)
p
=
0.055
No. at Risk
Placebo
1912 1484 807 374 194
Indapamide SR
±
perinodpril
1933 1557 873 417 229
Fig. 2. Total mortality (21% reduction).
30
20
10
0
0
1
2
3
4
No. of events per 100 patients
Placebo Indapamide SR
±
perinodpril
Follow up (year)
p
=
0.019
No. at Risk
Placebo
1912 1492 814 379 202
Indapamide SR
±
perinodpril
1933 1565 877 420 231
Fig. 3. Fatal stroke (39% reduction).
5
4
3
2
1
0
0
1
2
3
4
No. of events per 100 patients
Placebo Indapamide SR
±
perinodpril
Follow up (year)
p
=
0.046
No. at Risk
Placebo
1912 1492 814 379 202
Indapamide SR
±
perinodpril
1933 1565 877 420 231