Cardiac troponin increases among runners in the Boston Marathon.
OBJECTIVE
Studies indicate that running a marathon can be associated with increases in serum cardiac troponin levels. The clinical significance of such increases remains unclear. We seek to determine the prevalence of troponin increases and epidemiologic factors associated with these increases in a large and heterogeneous cohort of marathon finishers.


METHODS
Entrants in the 2002 Boston Marathon were recruited 1 to 2 days before the race. Data collected included demographic and training history, symptoms experienced during the run, and postrace troponin T and I levels. Simple descriptive statistics were performed to describe the prevalence of troponin increases and runner characteristics.


RESULTS
Of 766 runners enrolled, 482 had blood analyzed at the finish line. In all, 34% were women, 20% were younger than 30 years, and 92% had run at least 1 previous marathon. Most runners (68%) had some degree of postrace troponin increase (troponin T > or = 0.01 ng/mL or troponin I > or = 0.1 ng/mL), and 55 (11%) had significant increases (troponin T > or = 0.075 ng/mL or troponin I > or = 0.5 ng/mL). Running inexperience (< 5 previous marathons) and young age (< 30 years) were associated with elevated troponins. These correlates were robust throughout a wide range of troponin thresholds considered. Health factors, family history, training, race performance, and symptoms were not associated with increases.


CONCLUSIONS
Troponin increases were relatively common among marathon finishers and can reach levels typically diagnostic for acute myocardial infarction. Less marathon experience and younger age appeared to be associated with troponin increases, whereas race duration and the presence of traditional cardiovascular risk factors were not. Further work is needed to determine the clinical significance of these findings.
Fortescue
Elizabeth B
EB
Department of Cardiology, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA. elizabeth.fortescue@cardio.chboston.org
Shin
Andrew Y
AY
Greenes
David S
DS
Mannix
Rebekah C
RC
Agarwal
Suneet
S
Feldman
Brian J
BJ
Shah
Manish I
MI
Rifai
Nader
N
Landzberg
Michael J
MJ
Newburger
Jane W
JW
Almond
Christopher S D
CS
D000328:Adult; D000886:Anthropometry; D001900:Boston; D005260:Female; D006801:Humans; D008297:Male; D012420:Running; D014336:Troponin / Q000097:blood*
D014336:Troponin