LONDON, March 31 /CNW/ - Lowering the blood pressure of elderly patients
could cut their total mortality by a fifth and their rate of cardiovascular
events by a third, according to a new study presented today at the American
College of Cardiology in Chicago and published simultaneously in the New
England Journal of Medicine.
The 3,845 patient Hypertension in the Very Elderly Trial (HYVET), which
is co-ordinated by scientists from Imperial College London, is the largest
ever clinical trial to look at the effects of lowering blood pressure solely
in those aged 80 and over. Patients were given either a placebo or the
diuretic indapamide slow release (SR) 1.5mg, with the addition of the ACE
inhibitor perindopril in tablet form once a day.
The research shows that the benefits of treatment include a 21% (p equals
0.02) reduction in total mortality rate, a 39% (p equals 0.05) reduction in
stroke mortality rate, a 64% (p less than 0.001) reduction in fatal and
non-fatal heart failures and a 34% (p less than 0.001) reduction in
cardiovascular events. The benefits were apparent within the first year of
The reduction in overall mortality was a novel and unexpected result.
Earlier trials had demonstrated that reducing blood pressure in the under-80s
reduces stroke and cardiovascular events. However, previous smaller and
inconclusive studies also suggested that whilst lowering blood pressure in
those aged 80 or over reduced the number of strokes, it did not reduce, and
even possibly increased, total mortality.
In July 2007 the trial was stopped early on the recommendation of an
independent data monitoring committee after they observed significant
reductions in overall mortality and stroke in those receiving treatment. The
final results of the trial showed a significant reduction in stroke mortality
rate, but the reduction in all strokes of 30% did not quite reach statistical
significance (p=0.06). In those aged 80 and over, up to half of strokes are
fatal and the reduction in fatal strokes is an important finding.
Emeritus Professor Christopher Bulpitt, the lead investigator on the
study from the Care of the Elderly Group at Imperial College London, said:
"Before our study, doctors were unsure about whether very elderly people with
high blood pressure could see the same benefits from treatment to lower their
blood pressure as those we see in younger people. Our results clearly show
that many patients aged 80 and over could benefit greatly from treatment.
Populations are living longer and we have growing numbers of people
living well into their 80s and beyond, so this is good news. We are very
pleased that cardiovascular events were reduced safely with a reduction in
The researchers hope that their findings will clear up uncertainty
amongst clinicians about the benefits of treating those aged 80 and over for
high blood pressure.
Dr Nigel Beckett, the trial co-ordinator from the Care of the Elderly
Group at Imperial College London, added: "Many very elderly people with high
blood pressure are not being treated for it at the moment, because doctors are
unsure about whether or not treatment will help them. We hope that following
our study, doctors will be encouraged to treat such patients in accordance
with our protocol."
As the trial was stopped early, an extension involving patients receiving
active-treatment is now underway to assess the longer term benefits of
Patients with high blood pressure (defined here as a systolic blood
pressure between 160-199 mmHg), from thirteen countries across the world, were
randomised for the double-blind, placebo-controlled trial, which began in
2001. The mean age of participants was 83 years and 7 months.
Patients were given either placebo or indapamide slow release (SR) with
the addition of perindopril, in tablet form once a day as required, to achieve
a target blood pressure of 150/80 mmHg. The average follow-up of patients was
just over 2 years by which time 20% of the placebo subjects and 48% of those
taking medication had achieved the target blood pressure of 150/80 mmHg. In
those patients who were followed up for longer, a larger number of patients
receiving active treatment achieved the target blood pressure.
HYVET was co-ordinated by scientists from Imperial College London,
working with colleagues around the world. The main trial was funded by both
the British Heart Foundation and by Servier.
Notes to editors
1. About high blood pressure and stroke
- Stroke is the third most common cause of death in England and Wales.
In 2004, 11% of deaths amongst those aged 75-84, and 14% of deaths
amongst those aged over 85 were due to stroke, according to the
Office of National Statistics.
- In the UK about 150,000 people suffer a stroke each year, the
equivalent of 1 every 4 minutes.
- About one third of stroke patients die within 6 months of the event,
the majority occurring in the first month.
- Disability after stroke is the most important single cause of severe
disability of people living in their own homes.
- There are 2 types of strokes:
a. Haemorrhagic - caused by blood leaking into brain tissue from a blood
vessel within the brain.
b. Ischaemic - caused by a clot occluding a blood vessel, resulting in
loss of blood supply to a part of the brain and subsequent damage to
High blood pressure increases the chance of both a blood vessel leaking or
rupturing, and of a clot forming within a blood vessel. High blood pressure
increases the likelihood of damage to the lining of the blood vessel, which in
turn leads to an increased chance of spontaneous clot formation within the
- The over 80s are the fastest growing group in the population
worldwide - in the UK currently they account for 4% of the total
population and this is expected to rise to over 11% by 2050.
- The risk of stroke increases with age, with some estimates suggesting
that the risk doubles every decade after a person reaches 55 years of
- In the UK approximately 4% of the total National Health Service
budget is spent on stroke services each year.
2. About Imperial College London
Imperial College London - rated the world's fifth best university in the
2007 Times Higher Education Supplement University Rankings - is a
science-based institution with a reputation for excellence in teaching and
research that attracts 12,000 students and 6,000 staff of the highest
international quality. Innovative research at the College explores the
interface between science, medicine, engineering and business, delivering
practical solutions that improve quality of life and the environment -
underpinned by a dynamic enterprise culture.
There will be a press briefing to discuss these findings in Chicago on
Monday 31 March at 10:00 CDT/16:00 BST. Details of how to dial in and/or watch
live streaming of the briefing can be obtained from the ACC Press Office
For further information:
For further information: Laura Gallagher, Senior Press Officer, Imperial
College London, e-mail: L.Gallagher@imperial.ac.uk, Telephone:
+44(0)20-7594-6702 or ext. 46702, Out of hours Duty Press Officer:
+44(0)7803-886-248, Web: http://www.imperial.ac.uk/press, Website: