Objective: To compare the efficacy and safety of statin (HMG-CoA reductase inhibitor) monotherapy versus ezetimibe 10mg plus statin in older and younger adults with primary hypercholesterolaemia. Patients and methods: Four multicentre, randomised, double-blind, placebo-controlled, balanced parallel-group trials were pooled for analysis. After washout and placebo run-in period, men and women greater than or equal to 18 years of age (n = 186 1) with primary hypercholesterolaemia (plasma low-density lipoprotein-cholesterol [LDL-C] level from 3.76 to greater than or equal to 6.48 mmol/L and triglycerides less than or equal to 3.95 mmol/L) were randomised to either placebo, statin.monotherapy (lovastatin or pravastatin 10, 20 or 40mg, simvastatin or atorvastatin,10, 20, 40 or 80mg) or ezetimibe plus statin for 12 weeks. For each study, the primary efficacy endpoint was the percentage reduction in LDL-C from -baseline to, study endpoint. In the present study, age subset analyses on data pooled,across these four trials were carried out to determine whether coadministration of ezetimibe and statin was equally efficacious across specific age groupings: age <65 versus greater than or equal to65 years; age <75 versus greater than or equal to75 years. Results: Across age groupings, coadministration of ezetimibe and statin produced significant incremental reductions in LDL-C compared with statin monotherapy. The beneficial effects of ezetimibe plus statin on LDL-C, triglycerides and high-density lipoprotein-cholesterol (HDL-C) were overall independent of age groupings. Ezetimibe plus statin therapy was generally well tolerated, with similar incidence of adverse events, serious adverse events and changes in liver function and muscle enzymes in the given age groups compared with statin therapy alone. Conclusion: The beneficial effects of ezetimibe coadministered with statins on LDL-C, triglycerides and HDL-C were similar between older and younger hypercholesterolaemic patients, with a favourable safety profile across all patient age groups.