Sex and Population-Specific 99th Percentiles of Troponin for Myocardial Infarction in the Danish Population (DANSPOT)

BACKGROUND: Sex- and population-specific 99th percentiles of high-sensitivity cardiac troponin (hs-cTn) are recommended in guidelines although the evidence for a clinical utility is sparse. The DANSPOT trial will investigate the clinical effect of sex- and population-specific 99th percentiles of cTn. We report the 99th percentiles derived from this trial and their dependency on kidney function.

METHODS: We used samples from healthy Danish blood donors and measured hemoglobin A1c, N-terminal pro-brain natriuretic peptide and creatinine, and calculated an estimated glomerular filtration rate (eGFR). We compared 2 cutoffs for the eGFR of healthy participants (60 vs 90 mL/min/1.73 m2). The cTn assays investigated were Siemens Atellica and Dimension Vista hs-cTnI, Abbott hs-cTnI, and Roche hs-cTnT.

RESULTS: A total of 2287 participants were sampled, of which 71 (3.1%) were excluded due to a history of heart disease (n = 4), insufficient material (n = 7), or a screening biomarker (n = 60). Of the remaining 2216 participants, 1325 (59.8%) had an eGFR ≥90 mL/min/1.73 m2. Compared to a cutoff of 60 mL/min/1.73 m2 for eGFR, using 90 mL/min/1.73 m2 resulted in lower 99th percentiles for females; Siemens Vista (46 vs 70 ng/L), Abbott (14 vs 18 ng/L), and Roche cTnT (10 vs 13 ng/L), and decreased the number of measurements above the manufacturers' 99th percentiles for all assays.

CONCLUSIONS: We present reference values for 4 cTn assays for eGFR cutoffs of 60 and 90 mL/min/1.73 m2. These cutoffs differ based on the eGFR threshold for inclusion indicating that any chosen cutoff is also valuable with moderately reduced kidney function.