MEDIA RELEASE
25th July 2008
ASPIRIN
PREVENTATIVE THERAPY REDUCES
HEART ATTACK AND STROKE RISKS
If every person at risk of cardiovascular events took low-dose
aspirin and the other preventative therapies recommended for them,
there would be 63 per cent fewer heart attacks and 31 per cent
fewer strokes over a 30-year period, according to a US study.(1)
Even assuming 'more feasible' levels of uptake (estimated from
the clinical experience of health care organisations) these interventions
would reduce heart attacks by 36 per cent and strokes by 20 per
cent.
The study applied a computer model of disease and treatment outcomes,
known as Archimedes, to a virtual population representative of
the US population. The model then simulated a series of 30-year
clinical trials of 11 interventions known to reduce cardiovascular
events. (2)
Overall, 78 per cent of the population were eligible for at least
one intervention. If all the interventions were implemented for
everyone who was eligible to receive them, the model estimated
that heart attacks would fall by 63 per cent and strokes by 31
per cent over 30 years.
If low-dose aspirin was fully implemented, there would be 8 per
cent fewer heart attacks and one per cent fewer strokes in the
population as a whole. Assuming feasible implementation of low-dose
aspirin, namely that half of eligible people take it, there would
be 4 per cent fewer heart attacks overall but little reduction
in (0.005 per cent) in strokes.
In the subgroup of people taking it, low-dose aspirin would reduce
heart attacks by 18.6 per cent and strokes by 1.8 per cent.
Smoking cessation was the only intervention that would reduce
health costs over the 30 year period; of the remainder, low-dose
aspirin was the most cost effective at $2799 per quality-adjusted
life-year gained (3) (based on US health care costs).
The authors conclude that death and illness from cardiovascular
disease could be greatly reduced if people at risk received the
preventative therapies they need. They note that the most important
components of the cost of preventing cardiovascular events are
drug costs and the costs of programmes for weight reduction and
smoking cessation. Low-dose aspirin is the least expensive of
the interventions to reduce cardiovascular disease.
Professor Peter Elwood, Department of Primary Care and Public
Health, School of Medicine, Cardiff University, comments: The
overall conclusion of this most interesting paper is that of all
the possible preventive activities ‘the greatest benefits
to the US population come from providing aspirin to high-risk
individuals’. In studies of representative population samples
in Wales we found that, by the age of 50 years, 80 per cent of
men and 50 per cent of women had reached or exceeded a level of
risk of a heart attack or stroke at which low-dose aspirin should
be recommended.(4) In the Archimedes model, Kahn et al assumed
that 70% of the ‘at risk’ population in the United
States is already taking aspirin.1 Unfortunately, we simply do
not know this proportion in the UK but it is likely to be very
much less than 70% - giving us the opportunity for even greater
benefits from encouraging appropriate use of low-dose aspirin
within the UK.
ENDS
Notes to editors
1. The reference for this publication is Kahn R, Robertson RM,
Smith R, Eddy D. The impact of prevention of reducing the burden
of cardiovascular disease. Circulation 2008; published online
July 7th. DOI 10.1161/CIRCULATIONAHA.108.190186
2. The interventions studied were:
• low-dose aspirin for people with a 10-year risk of myocardial
infarction =10% (feasible performance 50 per cent)
• reducing LDL-cholesterol to <4.1 mmol/l in low-risk
individuals (75 per cent)
• reducing LDL-cholesterol to <3.3 mmol/l in high-risk
individuals (70 per cent)
• reducing LDL-cholesterol to <2.6 mmol/l in people with
coronary artery disease (70 percent)
• lower blood pressure to <140/90 mmHg in nondiabetic
people (75 per cent)
• lower HbA1C to <7% in people with diabetes (60 percent)
• lower blood pressure to <130/80 mmHg in people with
diabetes (60 per cent)
• lower LDL-cholesterol to <2.6 mmol/l in people with
diabetes (65 per cent)
• reduce fasting plasma glucose to 6.1 mmol/l (60 per cent)
• smoking cessation (30 per cent)
• reduce body mass index to <30 kg.m2 (20 per cent)
3. A quality-adjusted life-year (QALY) is a measure widely used
in health economics that describes the increase in life expectancy
from an intervention adjusted for quality of life.
4. Elwood P, Morgan G, Brown G, Pickering J. Aspirin for everyone
older than 50? Br Med J 2005;330:1440-1
