Age-sex Distribution Of Patients With High-sensitivity Troponin T Levels Below The 99th Percentile

Background: Recently,very low concentrations of high-sensitivity cardiac troponin T(hs-c Tn T),below the 99 th percentile,have been used to immediately exclude acute myocardial infarction in certain patients without taking their age and sex into consideration.Materials and Methods: From January 1st,2015 to October 31 st,2015,5585 consecutive subjects(2980 males and 2605 females)aged 4-104 years who presented with non-traumatic chest pain/discomfort to the inpatient,outpatient,or emergency department and who underwent hs-c Tn T,myoglobin(Myo)and creatine kinase-MB(CK-MB)testing a tpresentation,with hs-c Tn T below the 99 th percentile(?14 ng/L),were eligible for enrollment.Skewed data,including age,hs-c Tn T,Myo,and CK-MB were expressed as medians and quartile ranges,and comparisons were performed using the Mann-Whitney U test and the Kruskal-Wallis H test.The Spearman two-way test was used to assess the relationship between two quantitative variables.Results: The hs-cTnT values below the 99 th percentile(?14 ng/L)were higher in men(p = 0.000)and significantly increased with age(p = 0.000)among both men and women.In addition,the Spearman correlation analyses indicated that hs-c Tn T was positively associated with age(r = 0.459,p = 0.000),Myo(r = 0.392,p = 0.000),and CK-MB(r = 0.133,p = 0.000).Moreover,the proportion of males(p = 0.006)was greater than that of females in each quartile of age.Furthermore,males were younger(p = 0.001)and had higher Myo(p = 0.000)and CK-MB(p = 0.000)concentrations than females.Conclusions:Age and sex differences were significant in patients with hs-cTnT values below the 99 th percentile(?14 ng/L).Moreover,interactions among sex,age,hs-c Tn T,Myo and CK-MB were found.The clinical implications of our findings are that the use of very low hs-c Tn T concentrations for ruling out AMI and/or adverse prognostic implications should take into account patients' age and sex and should be combined with the analysis of other myocardial injury biomarkers,.This approach could improve the specificity and accuracy of AMI diagnosis,reducing the misclassification of patients and unnecessary hospital admissions.