Prevalence of cardiac troponin elevations in athletes following running, cycling, or walking events
Authors: Janssen S L J , Lamers S K , Vroemen W H M , Berge K , Denessen E J S , Aengevaeren V L A , Bekers O , Hopman M T E , Mingels A M A , Eijsvogels T M H 
Published: June 2024

Abstract

Background
Cardiac troponins (cTn) are the standard biomarkers to assess myocardial injury. Exercise can result in cTn elevations above the upper reference limit (URL) which were previously associated with adverse health outcomes. However, it remains unclear if sport type influences the prevalence of elevated cTn concentrations.

Purpose
To compare the prevalence of cTnT and cTnI elevations in recreational athletes following the completion of a mass-participation running, cycling, or walking event.

Methods
We recruited recreational athletes ≥40 and &lt;70 years old who participated in mass-participation sports events with a minimum distance of running ≥15 km, cycling ≥100 km, or walking ≥20 km. We measured high-sensitivity (hs-)cTnT and hs-cTnI concentrations at baseline (i.e. pre-exercise) and ≤6 hours after exercise cessation. Hs-cTnT &gt;14 ng/L and hs-cTnI &gt;26 ng/L were considered elevated (i.e. &gt;URL) according to package inserts. Differences in the prevalence of cTn elevations across sport types were assessed with logistic regression models while adjusting for age, sex, and baseline cTn.

Results
A total of 1,015 participants were included, consisting of n=398 runners (median 53 Q1–Q3 [47–59] years old, 72.1% male), n=120 cyclists (55 [48–60] years old, 90.0% male) and n=497 walkers (58 [52–63] years old, 48.9% male). Baseline hs-cTnT and hs-cTnI were 6.3 [ 4.9–8.3] ng/L and 0.0 [0.0–2.4] ng/L for the runners, 7.3 [5.6–9.0] ng/L and 1.5 [0.6–3.0] for the cyclists, and 5.9 [4.7–8.2] ng/L and 1.8 [1.1–3.0] ng/L for the walkers, respectively (both p&lt;.001). At baseline, 3.7% and 3.5% of the study cohort had elevated hs-cTnT and hs-cTnI, respectively.
Exercise resulted in significantly greater hs-cTnT in runners (21.8 [15.9–30.3) ng/L) and cyclists (21.6 [14.6–30.4] ng/L) versus walkers (8.8 [6.6–12.6] ng/L, p&lt;0.001). Likewise, hs-cTnI concentrations in runners (10.4 [5.1–22.3] ng/L) and cyclists (17.9 [9.7–31.2] ng/L) were higher compared to walkers (5.3 [3.2–9.6] ng/L, p&lt;.001). The overall prevalence of elevated post-exercise hs-cTnT concentrations was 51.8%, with greater odds for runners (84.6%, adjusted OR: 67.8, 95%CI: 40.1–114.5) and cyclists (79.0%, adjusted OR: 32.2, 95%CI: 17.2–60.4) compared to walkers (18.5%, reference group). The overall prevalence of elevated post-exercise hs-cTnI concentrations was 15.9%, with again greater odds for runners (21.3%, adjusted OR: 3.9, 95%CI: 2.4–6.1) and cyclists (33.6%, adjusted OR: 7.3, 95%CI: 4.2–12.7) compared to walkers (7.3%, reference group).

Conclusions
Participants of running and cycling events had greater exercise-induced cTn elevations and more often exceeded the assay-specific upper reference limit, particularly when using a hs-cTnT assay, in comparison to walking events. These findings highlight the need for sport-specific URLs to prevent clinical confusion on the interpretation of post-exercise cTn elevations among recreational athletes following mass-participation sports events.