Sex-Specific Absolute Delta Thresholds for High-Sensitivity Cardiac Troponin T

Area of Science:

• Cardiology
• Biomarkers
• Emergency Medicine

Background:

• Sex differences in high-sensitivity cardiac troponin (hs-cTn) concentrations necessitate sex-specific reference limits.
• Existing hs-cTn assays have established sex-specific upper limits based on healthy populations.

Purpose of the Study:

• To assess the performance of sex-specific delta (change in concentration) thresholds for the hs-cTnT assay.
• To determine the utility of these thresholds for ruling in acute myocardial infarction (AMI) in emergency department (ED) patients.

Main Methods:

• Retrospective analysis of two cohorts (US and Canadian EDs) with serial hs-cTnT measurements (0-h/3-h algorithm).
• Derivation of sex-specific delta thresholds using the Youden index and ≥90% specificity in Cohort 1 (n=18,056).
• Validation of derived thresholds in Cohort 2 (n=1137).

Main Results:

• Males exhibited higher baseline and delta hs-cTnT concentrations than females in non-AMI patients.
• Sex-specific delta thresholds (14 ng/L for males, 11 ng/L for females) achieved ≥90% specificity for AMI.
• These thresholds yielded 91% diagnostic accuracy in both sexes and were validated in the second cohort.

Conclusions:

• Sex-specific absolute delta thresholds are effective for ruling in AMI.
• These thresholds demonstrate robustness and consistent performance across different ED populations.