Analytical performance and clinical efficacy for cardiovascular risk estimation of an Olympus immunoturbidimetric high-sensitivity C-reactive protein assay

Increased C-reactive protein (CRP) concentration within the reference interval (<10.0mg/L) is a strong predictor of cardiovascular disease (CVD) in apparently healthy adults. Cutoff points for use of CRP in estimating CVD risk are <1, 1–3 and >3mg/L for low, average and high relative risk, respectively. For measuring CRP concentrations to assess cardiovascular risk, high-sensitivity CRP (hsCRP) assays have been developed. The aim of this study was to evaluate the analytical performance and clinical efficacy for cardiovascular risk estimation of the Olympus immunoturbidimetric latex CRP assay (sensitive application). The comparative method used was the CardioPhase* hsCRP assay, approved by the Food and Drug Administration for use in CVD risk assessment. The imprecision of the Olympus hsCRP assay in the concentration range 0.2–10.0mg/L was 0.38–8.16% within runs and 3.75–9.63% between runs. For method comparison studies, 194 fresh serum samples were selected to cover the interval 0.15–10.0mg/L CRP. Comparison of the Dade Behring and Olympus methods was performed using weighted Deming regression analysis (slope 0.99mg/L, intercept 0.002mg/L, S