Impact of rosuvastatin use on costs and outcomes in patients at high risk for cardiovascular disease in US managed care and medicare populations: A data analysis.

BACKGROUND: High blood cholesterol is a major modifiable risk factor for coronary heart disease (CHD) and stroke.

OBJECTIVE: The aim of this study was to estimate the economic impact of rosuvastatin calcium use in patients at high risk for CHD and stroke, according to the National Cholesterol Education Program Adult Treatment Panel (ATP) III guidelines.

METHODS: An economic simulation model was developed that used a Markov process to project the number of cardiovascular events and associated costs in a high-risk population in various treatment scenarios. According to the ATP III, high-risk patients are those with CHD, atherosclerosis of peripheral and/or cerebral arteries, diabetes, and/or multiple other risk factors conferring a risk of at least 20% within 10 years. Data on population characteristics and costs of cardiovascular disease (CVD) were obtained from claims data sets from employer-funded commercial and Medicare health plans in the United States. Treatment of lipid disorders was translated into CVD risk reduction based on results from the Heart Protection Study. The estimated efficacies of individual lipid-lowering drugs were based on data published in package inserts. The model generated costs at the health plan level of lipid-lowering therapy in high-risk patients and the number and total costs of cardiovascular events. Estimates were compared for scenarios representing the mix of treatments used before and after the introduction of rosuvastatin. Estimates were generated separately for commercial and Medicare health plans.

RESULTS: For every 1 million members of a commercial health plan, an estimated 44,457 met ATP III criteria for high-risk status. Use of rosuvastatin in place of other 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors ("statins") by 11 % of these patients over a period of 5 years was estimated to result in 36 fewer cardiovascular events and a net savings of US 4.03 million dollars. A Medicare plan of 1 million members with an estimated 433,268 high-risk patients and 7% rosuvastatin use was estimated to avoid 727 events and save US 34.32 million dollars.

CONCLUSIONS: The results of this data analysis suggest that increasing the use of rosuvastatin can result in cardiovascular event reduction and cost savings. Because the impact of lipid-modifying therapy on cardiovascular risk has not been thoroughly documented in controlled clinical studies, our model assumed that incremental lipid changes had effects in proportion to the magnitude of change.