Defining baseline high-sensitivity cardiac troponin levels in healthy collegiate athletes

Cardiac troponin (cTn) is a critical biomarker for diagnosing myocardial injury; however, intense physical activity can transiently elevate cTn concentrations, creating diagnostic challenges in athletic populations. High-sensitivity cardiac troponin assays (hs-cTn) further complicate discrimination between physiologic and pathologic elevations.

This study characterized baseline high-sensitivity cardiac troponin I (hs-cTnI) distributions in collegiate athletes and evaluated associations with sex, time since exercise, sport type, and creatine kinase-MB (CK-MB). We analyzed baseline hs-cTnI values from 173 elite collegiate athletes (98 women, 75 men) representing 21 sports.

The median hs-cTnI concentration (<4 ng/L) was identical between sexes, but divergence emerged in the upper distribution tail, with hs-cTnI values exceeding population-derived 99th percentile upper reference limits occurring at lower percentiles in men than women (73rd vs 85th percentile), resulting in a higher prevalence of abnormal classifications in men (28% vs 17%, P < .01). Ninety-fifth percentile values were similar between sexes, whereas divergence was confined to the extreme upper tail (99th percentile). Abnormal hs-cTnI values were more frequent when samples were collected <48 hours after exercise compared with ≥48 hours (29% vs 16%, P = .04). No association was observed between hs-cTnI and CK-MB (P = .37). Significant differences emerged between sports (P = .02), with the highest proportions of abnormal hs-cTnI observed among cross-country (80%), sailing (44%), and rowing (35%) athletes.

These findings support athlete-focused interpretation of hs-cTnI incorporating sex-specific thresholds, standardized postexercise sampling, and sport context. Such tailored approaches may reduce false-positive results and unnecessary evaluations while preserving diagnostic accuracy for true myocardial pathology.