Background:
Although statins reduce coronary and cerebrovascular morbidity
and mortality in middle-aged individuals, their efficacy and safety in
elderly people is not fully established. Our aim was to test the
benefits of pravastatin treatment in an elderly cohort of men and women
with, or at high risk of developing, cardiovascular disease and stroke.Method:
We did a randomized controlled trial in which we assigned 5804 men
(n=2804) and women (n=3000) aged 70-82 years with a history of, or risk
factors for, vascular disease to pravastatin (40 mg/day; n=2891) or
placebo (n=2913). Baseline cholesterol concentrations ranged from
4.0 mmol/L to 9.0 mmol/L. Follow-up was 3.2 years on average and our
primary endpoint was a composite of coronary death, non-fatal myocardial
infarction, and fatal or non-fatal stroke. Analysis was by
intention-to-treat.
Findings:
Pravastatin lowered LDL cholesterol concentrations by 34% and
reduced the incidence of the primary endpoint to 408 events compared with
473 on placebo (hazard ratio 0.85, 95% CI 0.74-0.97, p=0.014).
Coronary heart disease death and non-fatal myocardial infarction risk was
also reduced (0.81, 0.69-0.94, p=0.006). Stroke risk was unaffected
(1.03, 0.81-1.31, p=0.8), but the hazard ratio for transient ischemic
attach was 0.75 (0.55-1.00, p=0.051). New cancer diagnoses were more
frequent on pravastatin than on placebo (1.25, 1.04-1.51, p=0.020).
However, incorporation of this finding in a meta-analysis of all
pravastatin and all statin trials showed no overall increase in
risk. Mortality from coronary disease fell by 24% (p=0.043) in the
pravastatin group. Pravastatin had no significant effect on
cognitive function or disability.
Interpretation:
Pravastatin given for 3 years reduced the risk of coronary disease
in elderly individuals. PROSPER therefore extends to elderly
individuals the treatment strategy currently used in middle-aged people. |
