WOSCOPS: Identification of High-Risk Groups and Comparison with Other Cardiovascular Intervention Trials

This subgroup analysis of the WOSCOPS (West of Scotland Coronary Prevention Study) trial identified high-risk subgroups within the 6,595-man primary prevention cohort that received the greatest absolute benefit from pravastatin, and compared treatment efficiency with other contemporaneous cardiovascular prevention trials.

Men aged ≥55 with at least one additional cardiovascular risk factor, or men with pre-existing vascular disease, had 10-year coronary event rates exceeding 10% — meeting thresholds where statin treatment was clinically and economically comparable to blood pressure treatment for stroke prevention. The number-needed-to-treat in these high-risk WOSCOPS subgroups was substantially lower than for the full unselected cohort.

WOSCOPS was a landmark primary prevention statin trial — the first large-scale RCT to demonstrate that pravastatin significantly reduces cardiovascular events in men with no prior MI. This subgroup analysis made the case that within a primary prevention trial population, risk-stratified targeting could improve treatment efficiency.

The underlying principle — that statin benefit is proportional to absolute cardiovascular risk, and that high-risk primary prevention patients achieve NNTs comparable to secondary prevention — is now central to ACC/AHA guidelines’ benefit-group framework, which emphasizes absolute risk calculation over LDL-C thresholds alone.

We rate the evidence moderate. A subgroup analysis of the WOSCOPS trial demonstrating that high-risk primary prevention men derive clinically meaningful statin benefit — early evidence for risk-stratified statin prescribing in primary prevention.