Changes to the statin prescribing policy in Belgium: Potential impact in clinical and economic terms

Background and Objective: New policies in Belgium encourage prescribing of generic HMG-CoA reductase inhibitors (statins), but may lead to non-equivalent switching of patients from more potent second generation statins, as has occurred elsewhere. We sought to assess the potential health economic impact of the new policies. Design: This was a cost-effectiveness analysis. Methods:AMarkov model was constructed to simulate the onset of cardiovascular disease (CVD) and death among a representative cohort of 80 Belgian patients initially free of CVD and taking atorvastatin. Cardiovascular risks were estimated from calibrated Framingham equations, and utilities and costs from published data. Decision analysis assessed the potential impact of switching all 80 patients to simvastatin. Changes in lipid levels expected to arise from switching were based on a published meta-analysis. Results: If the 80 patients remained on atorvastatin, the model predicted that 23 (29%) would develop CVD over 20 years. If they were switched to simvastatin, the predicted number was 25 (31%), equating to a "number needed to harm" of 52. Switching would lead to a net cost saving of €131 (2012) per subject, but also a loss of 0.03 quality-adjusted life-years (QALYs) per subject. These equated to a decremental costeffectiveness ratio of €4777 per QALY lost. Sensitivity analyses indicated this result to be robust. Conclusion: Recently introduced statin prescribing policies in Belgium are likely, as intended, to reduce statin costs, but also increase the burden of CVD due to non-equivalent switching. It would be cost effective to maintain patients on atorvastatin for primary prevention rather than switch them to simvastatin.