title: Cardiorespiratory Fitness and Highly Sensitive Cardiac Troponin Levels in a Preventive Medicine Cohort.
abstract: Cardiorespiratory fitness (CRF) and highly sensitive cardiac troponin T (hs-cTnT) are associated with risk of all-cause and cardiovascular mortality as well as incident heart failure. A link of low CRF to subclinical cardiac injury may explain this association. We hypothesized that CRF would be inversely associated with hs-cTnT measured in healthy adults over age 50.
  
  
  
  We evaluated 2498 participants (24.7% female, mean age 58.7 years) from the Cooper Center Longitudinal Study between August 2008 and January 2012. Plasma specimens obtained shortly before CRF estimates by Balke treadmill testing were used for hs-cTnT assays. CRF was grouped into low CRF (category 1), moderate CRF (categories 2-3), and high CRF (categories 4-5). Multivariable logistic regression was used to estimate the association of CRF with hs-cTnT. The prevalence of measurable hs-cTnT (≥3 ng/L) was 78.5%. In multivariable analyses, low-fit individuals were significantly more likely than high-fit individuals to have elevated hs-cTnT (≥14 ng/L) (odds ratio 2.47, 95% CI 1.10-5.36).
  
  
  
  In healthy older adults, CRF is inversely associated with hs-cTnT level adjusted for other risk factors. Prospective studies are needed to evaluate whether improving CRF is effective in preventing subclinical cardiac injury.
authors.affiliation: Cooper Institute, Dallas, TX ldefina@cooperinst.org.
authors.forename: Laura F
authors.initials: LF
authors.lastname: DeFina
authors.affiliation: Cooper Institute, Dallas, TX.
authors.forename: Benjamin L
authors.initials: BL
authors.lastname: Willis
authors.affiliation: Cooper Clinic, Dallas, TX.
authors.forename: Nina B
authors.initials: NB
authors.lastname: Radford
authors.affiliation: Department of Pathology, University of Maryland School of Medicine, Baltimore, MD.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Christenson
authors.affiliation: Division of Cardiovascular Medicine, University of Maryland School of Medicine, Baltimore, MD.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: deFilippi
authors.affiliation: Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, TX.
authors.forename: James A
authors.initials: JA
authors.lastname: de Lemos
mesh_terms: D000368:Aged; D000072599:Cardiorespiratory Fitness; D015331:Cohort Studies; D005080:Exercise Test; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D020107:Troponin T / Q000097:blood*
chemical_list: D020107:Troponin T
keywords: cardiorespiratory fitness; exercise capacity; hs‐cTnT; troponin