PEOPLE AT LOW RISK OF VASCULAR DISEASE
The benefits of statins apply both to those at high risk and those at low risk of vascular disease
Previous CTT meta-analyses had shown that statins reduce LDL cholesterol and prevent major vascular events, but their net effects in people at low risk of vascular events (ie, in the context of primary prevention of such events) remained unclear. The CTT Collaboration undertook meta-analyses to help resolve these uncertainties.
This meta-analyses included individual participant data from 22 randomized trials of statin versus control (involving approximately 130,000 individuals) and 5 randomized trials involving more versus less intensive statin regimens (involving approximately 40,000 individuals). Median follow-up was approximately 5 years.
Participants were separated into five categories of baseline 5-year risk of a major vascular event: <5%, ≥5% to <10%, ≥10% to <20%, ≥20% to <30%, ≥30%).
Reduction of LDL cholesterol with a statin reduced the risk of major vascular events by approximately a fifth per 1.0 mmol/L LDL cholesterol reduction, largely irrespective of age, sex, baseline LDL cholesterol or previous vascular disease.
The proportional reduction in major vascular events was at least as big in the two lowest risk categories as in the higher risk categories, which reflected significant reductions in these two lowest risk categories in major coronary events and in coronary revascularizations.
For stroke, the reduction in risk in participants with 5-year risk of major vascular events lower than 10% was also similar to that seen in higher risk categories.
In participants without a history of vascular disease, statins reduced the risks of vascular and all-cause mortality and the proportional reductions were similar at different levels of baseline risk.
In individuals with 5-year risk of major vascular events lower than 10%, each 1 mmol/L reduction in LDL cholesterol produced an absolute reduction of about 11 fewer major vascular events per 1000 treated over 5 years.