Medical-economical aspects of high sensitivity C-reactive protein assay for the prediction of coronary heart disease. An analysis in Germany and Italy.

BACKGROUND

Elevated plasma concentrations of C-reactive protein (CRP) are associated with increased cardiovascular risk. We studied the cost-effectiveness of CRP determination in primary and secondary prevention settings in two European countries: Germany and Italy.

METHODS

Using a decision analytic model we evaluated the costs and consequences of testing or not testing using a high sensitivity (hs)-CRP assay. In a primary prevention model we analyzed a hypothetical cohort of 300000 apparently healthy men divided into three age groups (35-44, 45-54 and 55-64 years). Individuals with CRP levels > 3 mg/l were administered either aspirin or statins according to lipid levels. The cohort was followed for 5 years. In the secondary prevention model hs-CRP testing was evaluated in a cohort of 10000 patients with total cholesterol levels < 4.52 mmol/l and a history of myocardial infarction or unstable angina. The two strategies tested were: 1) administer pravastatin only to those with high CRP values, and 2) treat all patients. The analysis was performed from the societal perspective. Event rates were obtained from epidemiological studies and clinical trials.

RESULTS

In the primary prevention model, strategies including testing showed, for men aged 45 years and older, cost-effectiveness ratios between each life year saved (LYS) and cost savings in Germany equal to 10217euro and between each LYS and savings in Italy equal to 16950euro In the age group 35-44 years, therapy with aspirin showed cost-effectiveness ratios of 5318euro and 11203euro per LYS in Germany and in Italy respectively. The widespread use of statins showed an unfavorable cost-effectiveness profile: 44630euro per LYS in Germany and 36270euro per LYS in Italy. In the secondary prevention model, hs-testing for CRP can reduce the cost-effectiveness of pravastatin from 16400 to 6830euro per quality adjusted life year gained. Sensitivity analysis performed on the variables test price and costs of cardiovascular events resulted in minimal changes of the cost-effectiveness ratios.

CONCLUSIONS

Both in the primary and the secondary prevention settings, hs-testing for CRP can better target individuals at higher risk, thus improving outcomes and resulting in a more cost-effective strategy.