Cost-effectiveness analysis in coronary artery disease diagnosis: Choosing between laboratory markers

Abstract

OBJECTIVES: The use of lipids, lipoproteins, apolipoproteins and high sensitive CRP (hs-CRP) in coronary artery disease (CAD) diagnosis has been widely established, although cost- effectiveness of these laboratory tests is not completely estab- lished. METHODS: We constructed 4 models (models with low, middle, high and very high risk for CAD, according to ATP III recommendation). The diagnostic capabilities of laboratory test combinations differs in terms of included markers: total choles- terol (TC), triglycerides (TG), HDL-c, LDL-c, apolipoproteins B and A-I (apo B and apo A-I), lipoprotein (a) (Lp(a)), apo(a) iso- forms and hs-CRP for establishing risk of CAD. The effective- ness of the laboratory test combinations, in number needed to diagnose (NND), was established on the random sample of 221 CAD patients who were undergoing coronary angiography and 297 healthy subjects with no history of CAD. The direct medical costs include price of test reagents and consumables specific to each test, disposables need for specimen collection and sample analysis, equipment amortization, and personal cost for labora- tory technologist. ICER and two-way sensitivity analyses were also calculated and applied. RESULTS: The cost per additional successfully diagnosed patient for TC, HDL-c and LDL-c labo- ratory test combination, were 2.4 and 35.4 euro (respectively), lower than the cost of the TC, HDL-c, apoB in low and TC, HDL-c, hs-CRP in very high risk groups. In high risk group, TC, HDL-h, LDL-h had effectiveness 15% (100/NND) lower than TC, HDL-c, hs-CRP, but overall saving was 11.9 euro. In middle risk group TC, LDL-c, apo A-I was chosen as the best alterna- tive. Such laboratory tests combination had effectiveness 17% lower then TC, LDL-h and hs-CRP, but savings was 6.2 euro. CONCLUSION: The cost-effectiveness analysis of different diagnostic test combinations allows better selection of risky patients at low cost for the society.