Application of a high-sensitivity cardiac troponin I assay to a health screen cohort of young Asian women and association with cardiovascular risk factors.

The Global Task Force for the Universal Definition of Myocardial Infarction and the National Academy of Clinical Biochemistry recommend the 99th percentile of cardiac troponin as a diagnostic threshold, provided that assay precision can be demonstrated to have a CV of 10% at this concentration (1). To determine the 99th percentile, we applied a high-sensitivity cardiac troponin I (hscTnI) assay (Abbott Diagnostics) to an analysis of a cohort of young, apparently healthy Asian women with low cardiovascular risk, and correlated this result with demographic and clinical characteristics to identify factors associated with higher cTnI concentrations. The cohort was obtained from our hospital staff health-screening program. Fasting serum samples were stored at 70 °C for up to 6 months until analysis. Nonpregnant women 20 – 65 years of age with no self-reported personal history of heart disease, diabetes, or hypertension were selected for analysis of cTnI concentrations with the Abbott ARCHITECT i4000 analyzer and a premarket prototype hscTnI assay. Institutional review board approval was obtained for this study (DSRB/2011/01931). SPSS version 19 (SPSS/IBM) was used for statistical analyses. We calculated precision from measurements obtained over 15 days with 10 dilutions of pooled serum (cTnI concentration, 1.0–110 ng/L). After removal of 2 outliers, we calculated the 99th percentile for the remaining data with a nonparametric method. The Student t-test and ANOVA were used to evaluate the statistical significance of the differences in cTnI concentrations with respect to smoking status, family history, metabolic syndrome, and ethnic groups. Multivariate logistic regression analysis was used to evaluate the relationships of the cTnI concentration to age, systolic blood pressure, waist circumference,