Drugs Xagena
The benefits of giving low dose Acetylsalicylic acid ( Aspirin ) to healthy individuals older than 70 to prevent cardiovascular disease are offset by increased risk of serious bleeding.
Current US guidelines recommend the use of low dose Aspirin ( 75-150 mg ) for people with a five year absolute coronary risk of ³ 3% or a 10 year absolute cardiovascular risk of ³ 10%.
If implemented, these recommendations would mean that most elderly people would be prescribed Aspirin prophylaxis because age is the greatest determinant of absolute risk.
Prophylactic use of a potentially toxic agent can be problematic, however, particularly
in people in whom comorbidity and polypharmacy are common.
In a prospective observational study in two large UK general hospitals, Aspirin was the causal agent in 18% of all admissions for adverse drug reactions and was implicated in 61% of all associated deaths.
Patients admitted with adverse drug reactions were significantly more likely to be older and female than those admitted without adverse drug reactions.
In contrast, the primary prevention clinical trials were conducted mostly in middle aged people.
The potential health gains of any preventive strategy need to be carefully balanced against their potential risks.
Australian researchers investigated the routine use of low dose Aspirin in 10 000 men and 10 000 women aged 70-74 without overt cardiovascular disease.
The main outcome measures were: first ever myocardial infarction or unstable angina, ischaemic or haemorrhagic stroke, and major gastrointestinal haemorrhage.
The proportional benefit gained from the use of low dose Aspirin by the prevention of myocardial infarctions and ischaemic stroke is offset by excess gastrointestinal and intracranial bleeding
Epidemiological modelling suggests that any benefits of low dose Aspirin on risk of cardiovascular disease in people aged ³ 70 are offset by adverse events.
Source: British Medical Journal, 2005
XagenaMedicine_2005
