Sex-specific, high-sensitivity cardiac troponin T cut-off concentrations for ruling out acute myocardial infarction with a single measurement

Abstract

ObjectiveSex-specific diagnostic cut-offs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction (MI). The objective of this study was to quantify test characteristics of sex-specific cut-offs of a single, high-sensitivity cardiac troponin T (hs-cTnT) assay for 7-day MI in patients with chest pain.MethodsThis observational cohort study included consecutive emergency department (ED) patients with suspected cardiac chest pain from four Canadian EDs who had an hs-cTnT assay performed within 60 minutes of ED arrival. The primary outcome was MI at 7 days. We quantified test characteristics (sensitivity, negative predictive value [NPV], likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific, rule-out cut-offs. We calculated the net reclassification index compared to universal rule-out cut-offs.ResultsIn 7,130 patients (3,931 men and 3,199 women), the 7-day MI incidence was 7.38% among men and 3.78% among women. Optimal sex-specific cut-offs (<8 ng/L for men and <7 ng/L for women) had a 98.5% sensitivity for MI and ruled out MI in 55.8% of patients. This would enable an absolute increase in the proportion of patients who were able to be ruled out with a single hs-cTnT of 13.2% to 22.2%, depending on the universal rule-out concentration used as a comparator.ConclusionsSex-specific hs-cTnT cut-offs for ruling out MI at ED arrival may improve classification performance, enabling more patients to be safely ruled out at ED arrival. However, differences between sex-specific and universal cut-off concentrations are within the variation of the assay, limiting the clinical utility of this approach. These findings should be confirmed in other data sets.

Gender Differences in Patients Admitted to a Certified German Chest Pain Unit: Results from the German Chest Pain Unit Registry

“…Presumably due to gender-specific differences in diagnoses and treatment and due to a higher rate of acute interventional need for therapy, more men were transferred to the catheterization laboratory or to the intensive care unit. The trend in male patients to be discharged directly from the CPU remains unclear but may be due to stricter rule-out parameters in men [35, 36]. The low in-CPU mortality without gender differences may be caused by good guideline adherence in certified German CPUs.…”

Sex-Specific Cut-Offs for High-Sensitivity Cardiac Troponin: Is Less More?

“…Although this study confirmed no advantage in risk prediction when using sex-specific reference values, the risk in women was increased at levels of 10-12 ng/L, which is below the set standard point of 14 ng/L [93]. A recent observational study, focused on the diagnostic performance of several sex-specific hs-cTnT cut-offs for the rule-out of MI, showed an improved specificity with the adoption of different threshold levels [94]. These findings were also consistent with a recent Chinese study in which sex-specific cut-offs were calculated in an original reference population and then further stratified according to age.…”

Using single sex-specific high-sensitivity cardiac troponin cut-off values for ruling out myocardial infarction – Are we there yet?

“…3,6,7 While studies have previously focused on improving ruling-in MI with sexspecific cut-offs, in this issue, McRae and colleagues explore the concept of ruling-out MI with a single Roche Elecsys® high-sensitivity cardiac troponin T (hs-cTnT), using several cut-off levels relative to the limit of detection (< 5 ng/L) and the Food and Drug Administration-approved limit of quantification (< 6 ng/L). 8 The 99th percentile reference limit for this assay is 14 ng/L. The study found that sex-specific cut-offs may improve the classification performance and could lead to rule out MI among more patients on ED arrival.…”