A-021 Comparing the Time Between the 1st and 2nd Troponin in Male and Female Patients in Singapore and Calgary, Alberta: Evidence of Extended Pre-preanalytical Time in Females with Low ACS Risk

Abstract Background At the 2022 AACC national meeting, in our assessment of reference change values (RCV) in troponins ordered in Calgary and Singapore, we postulated that there were gender differences in troponin-ordering between the two cities. Methods Singapore Changi Hospital ED patients [July 2018–July 2020] and Calgary patients [December 2017–December 2021] had hsTnT measured with the Roche Elecsys assay on multiple, local Cobas e801’s. The first two troponins of each patient were selected if they were ordered within 12 h. The troponin pairs were grouped by city, patient sex and whether the troponin pairs fulfilled the criteria of low likelihood of Acute Coronary Syndrome (ACS) according to city specific guidelines. Results The figure compares the average time difference between the first and second troponin test of females and males stratified by the initial troponin value. The paired t-test conducted shows that in Singapore there was no significant difference in the time for females and males to receive a second troponin test while in Calgary the time for females to receive a second troponin test was significantly longer (P < 0.0001) than males. Conclusion The significant difference between Calgary females and males in average time between the first and second troponin tests supports the idea that there may be gender specific differences in troponin ordering timing and patterns. 62%–68% of all laboratory errors originate from pre-pre-analytical processes of which timing is a factor. The well documented atypical presentation of myocardial infarction in females may contribute to the delayed second test in women. This timing difference may be a contributor to the RCV variance observed in our previous study which identified gender differences in the assessment of RCV in troponins ordered in Calgary and Singapore.