Background Sex differences in high-sensitivity cardiac troponin (hs-cTn) concentrations from healthy populations have led to the establishment of sex-specific upper reference limits for hs-cTn assays. This study assessed the performance of sex-specific delta (i.e., changes in concentrations) thresholds for the hs-cTnT assay for ruling in acute myocardial infarction (AMI) in different emergency department (ED) populations. Methods This retrospective study consisted of 2 cohorts (Cohort 1 derivation and Cohort 2 validation). Cohort 1 consisted of 18 056 ED patients who had serial hs-cTnT measured using a 0-h/3-h algorithm at a US medical center, with Cohort 2 consisting of 1137 ED patients with 0-h/3-h sampling at a Canadian medical center. The primary outcome was AMI diagnosis with sex-specific deltas derived based on the Youden index and specificity estimates (i.e., ≥90%) in Cohort 1 and validated in Cohort 2. Results In Cohort 1, 42% of all patients had 0-h hs-cTnT above the sex-specific 99th percentile. Males had higher 0-h hs-cTnT (median 17 ng/L) and absolute deltas (median 2 ng/L) than females (0-h median 11 ng/L, P < 0.0001; deltas median 1 ng/L, P < 0.0001) in non-AMI patients but not in patients with AMI. For ruling in AMI, the sex-specific delta thresholds based on 90% specificity (14 ng/L for males, 11 ng/L for females) performed best and resulted in 91% diagnostic accuracy in both males and females. The sex-specific delta thresholds yielding high specificity estimates were confirmed in the validation data set. Conclusions Sex-specific absolute delta thresholds can be used to rule in AMI and are robust across different study populations.

中文翻译：

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高灵敏度心肌肌钙蛋白 T 的性别特异性绝对 Delta 阈值

背景 健康人群中高敏心肌肌钙蛋白 (hs-cTn) 浓度的性别差异导致为 hs-cTn 测定建立性别特异性参考上限。本研究评估了在不同急诊科 (ED) 人群中用于判定急性心肌梗死 (AMI) 的 hs-cTnT 测定的性别特异性 delta（即浓度变化）阈值的性能。方法 这项回顾性研究包括 2 个队列（队列 1 推导和队列 2 验证）。队列 1 由 18 056 名 ED 患者组成，他们在美国医疗中心使用 0-h/3-h 算法进行了连续 hs-cTnT 测量，队列 2 由 1137 名 ED 患者组成，在加拿大医疗中心。主要结果是根据队列 1 中的约登指数和特异性估计（即≥90%）得出的 AMI 诊断，并在队列 2 中得到验证。结果在队列 1 中，42% 的所有患者有 0-h hs-cTnT 高于特定性别的第 99 个百分位数。男性的 0 小时 hs-cTnT（中位数 17 ng/L）和绝对增量（中位数 2 ng/L）高于女性（0 小时中位数 11 ng/L，P < 0.0001；增量中位数 1 ng/L， P < 0.0001) 在非 AMI 患者中，但在 AMI 患者中没有。对于 AMI 的判定，基于 90% 特异性（男性为 14 ng/L，女性为 11 ng/L）的性别特异性 delta 阈值表现最佳，男性和女性的诊断准确率均为 91%。在验证数据集中确认了产生高特异性估计的性别特异性增量阈值。