Impact of High-Sensitivity Troponin I Testing with Sex-Specific Cutoffs on the Diagnosis of Acute Myocardial Infarction.
High-sensitivity cardiac troponin I (hs-cTnI) assays show sex-dependent differences in the 99th percentile of healthy populations, with concentrations in women approximately 50% lower. The adoption of sex-specific cutoffs seems appropriate, although it is not yet clear what effect these will have on acute myocardial infarction (AMI) diagnosis and management.



We conducted a retrospective pre- and postchangeover analysis of troponin I testing in the 6 months before and after moving from the contemporary Abbott Architect TnI assay (cTnI) to hs-cTnI at 2 tertiary centers in Australia and New Zealand. The cTnI cutoff was 30 ng/L for both sexes, whereas a female-specific cutoff of 16 ng/L was adopted upon changeover to hsTnI.



Changeover from the cTnI assay to the hs-cTnI assay increased the number of female patients with increased troponin I concentrations at both sites (from 29.7% to 34.9% and from 22.4% to 30.8%; P < 0.001). There was no statistically significant change in the number of men with increased concentrations in the same time period (P = 0.09). The increased percentage of women with increased troponin I was not associated with an increase in the number of women with AMI diagnoses at either center. Angiographic data available from 1 center showed no change in the percentage of angiograms performed in women.



Although increasing the proportion of women with increased troponin I, adopting sex-specific cutoffs with the hs-cTnI assay did not lead to an increase in AMI diagnoses in females, or in the number of women undergoing angiography.
Clinical Biochemistry Unit, Alfred Pathology Service, Alfred Health, Melbourne, Australia;
Christina
C
Trambas
Emergency Department, Christchurch Hospital, and University of Otago, Christchurch, New Zealand;
John W
JW
Pickering
Emergency Department, Christchurch Hospital, and University of Otago, Christchurch, New Zealand;
Martin
M
Than
Health Informatics, Alfred Health, Melbourne, Australia;
Chris
C
Bain
Health Informatics, Alfred Health, Melbourne, Australia;
Lucy
L
Nie
School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia; Clinical Haematology Department, Alfred Hospital, Melbourne, Australia;
Eldho
E
Paul
Cardiology, Alfred Health, Melbourne, Australia; Central Clinical School, Monash University, Melbourne, Australia.
Anthony
A
Dart
Cardiology, Alfred Health, Melbourne, Australia;
Arch
A
Broughton
Clinical Biochemistry Unit, Alfred Pathology Service, Alfred Health, Melbourne, Australia; Central Clinical School, Monash University, Melbourne, Australia. h.schneider@alfred.org.au.
Hans Gerhard
HG
Schneider
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis*; D009520:New Zealand; D012189:Retrospective Studies; D012737:Sex Factors; D019210:Troponin I / Q000032:analysis*
D019210:Troponin I