OBJECTIVES: The use of statin has been shown to be cost effective in the secondary prevention of coronary heart disease and cerebrovascular disease. However, a ‘treatment gap’ exists, whereby many eligible patients do not receive statin therapy. We sought to determine the cost-effectiveness of closing this treatment gap in the Australian healthcare setting. METHODS: Analysis was based on 4-year follow-up data from Australian participants of the Reduction of Atherothrombosis for Continued Health (REACH) Registry. Subjects were aged ³45 years and had established atherothrombotic disease, comprising coronary artery disease (CAD), and cerebrovascular (CerVD) disease. Decision analysis was applied to compare current coverage with statin against a hypothetical situation whereby all subjects were assumed to be treated. Outcomes of interest were non-fatal stroke, non-fatal myocardial infraction (MI), and cardiovascular deaths. The relative changes to the risks of these outcomes conferred by statin were derived from published meta-analysis. Costs were based on government-reimbursed data for 2009. RESULTS: Among the sample of 2768 participants, coverage with statin therapy was between 63% and 82%, depending on age group. Over the 4-year period, 89, 101, and 146 non-fatal strokes, non-fatal MIs, and cardiovascular deaths were observed, respectively. Assuming that all subjects had taken statin, the predicted equivalent numbers were 85, 96 and 137 respectively. The estimated incremental cost-effectiveness ratio (ICER) for CAD subjects was AUD $45,274 per life-year gained (LYG). For CerVD subjects, the ICERs were AUD $40,738. Equating to numbers needed to treat of 136 and 99.5. Sensitivity analysis showed that the results were robust. CONCLUSIONS: The results of this model suggest that for subjects with athethrombotic disease, maximizing coverage with statin, in line with evidence-based recommendations, represents a cost-effective means of secondary prevention.