Objective: To assess the distribution of high-sensitivity cardiac troponin T (hs-cTnT) concentrations in stable chronic obstructive pulmonary disease (COPD), and whether hs-cTnT is associated with pulmonary function.
Design: Prospectively designed, cross-sectional study.
Setting: Outpatient clinic of Norwegian teaching hospital and community-based setting.
Participants: Sample of 101 stable COPD patients from the hospital's outpatient clinic and 120 individuals derived from a random general population sample.
Main outcomes: Ratio of hs-cTnT in stable COPD patients compared with references from the general population. Change in ratio of hs-cTnT per unit increase of relevant covariables.
Results: The crude geometric means of circulating hs-cTnT in the cases and the references were 7.75 and 3.01 ng/l, respectively (p < 0.001); that is, a relative ratio of 2.57 (95% CI 2.05 to 3.23). After adjustment for relevant confounders, this ratio was moderately attenuated to 1.65 (1.31-2.08). In the total study cohort, as well as among stable COPD patients, we found a significant positive association between hs-cTnT and interleukin-6 concentrations (p < 0.001) and the presence of pathologic Q waves (p = 0.023). Among stable COPD patients, one quartile increase in forced expiratory volume 1 was associated with a 39% decrease in hs-cTnT and patient category (Global Initiative of Obstructive Lung Disease classification 2011) was positively associated with hs-cTnT (p trend < 0.001) after multivariate adjustment.
Conclusions: Stable COPD is independently associated with higher hs-cTnT compared with randomly drawn subjects from the general population. In patients with stable COPD, higher hs-cTnT seems to be associated with immune activation and the severity of the disease.