Changes in Cardiac Biomarkers Post-Marathon in Male and Female Runners Across the Age Spectrum

Abstract

PURPOSE: To determine the effects of age and gender on cardiac troponin I (cTnI) and B-Type Natriuretic Peptide (BNP) levels post-marathon. METHODS: 13 female (42.54 ± 12.00 yrs old) and 9 male runners (46.55 ± 13.90 yrs old) were recruited to run the 2015 Hartford Marathon. The age distribution of the participants ranged from 22 to 63 years of age, with the following number of subjects recruited from each age range: 20-29 (n=3), 30-39 (n=5) 40-49 (n=6), 50-59 (n=5) 60-65 (n=3). A venous blood draw was taken from each subject at 3 time points (12 hours pre-race, immediately post-race and 20 hours post-race). cTnI and BNP levels were measured at each time point using a portable analyzer (Abbott iSTAT). To test for change in biomarkers across time points and the effects of age and gender, a multilevel mixed model was used with time point nested within runner. RESULTS: BNP levels increased significantly (p=0.013) from pre-race (33.27 pg/ml ± 6.29) to post-race (54.32 pg/ml ± 7.34) and remained above baseline (p=0.017) at 16 hours post-race (42.82 pg/ml ± 7.45). cTnI levels increased significantly (p=0.009) from pre-race (0.003 ng/ml ± 0.001) to post-race (0.044 ng/ml ± 0.008) and remained above baseline (p=0.004) at 16 hours post-race (0.024 ng/ml ± 0.004). No association was found for age and BNP (p=0.427) or cTnI (p=0.394) levels for any post-race time points. The change in cTnI levels between genders was also similar across all three-time points (p=0.63). However gender differences were found for BNP across time points. The increase in BNP levels, from pre-race to 20 hours post-race was more pronounced in females than males, with females experiencing an 87% greater change (27.3 pg/ml) than their male counterparts (p=0.047). CONCLUSION: BNP and cTnI levels were evaluated at both post-race time points indicating potential cardiac stress associated with marathon running. While no differences were found in BNP or cTnI across the age spectrum, female runners experienced a greater increase in BNP levels post-race. These results suggest that female runners may experience greater cardiac stress than their male counterparts as a result of marathon. Supported by Quinnipiac University School of Health Sciences, School of Medicine and School of Nursing.