Effect of CPAP treatment on plasma high sensitivity troponin levels in patients with obstructive sleep apnea

Abstract

Obstructive sleep apnea (OSA) is associated with an increased prevalence of cardiovascular diseases. New generations of highly sensitive assays for cardiac troponin (hs-cTnT) have been introduced recently, and a number of clinical observations have challenged the notion that troponins are only increased in blood following irreversible necrosis. The aims of this study were to compare the levels of hs-cTnT between a group of healthy controls and a group of patients with OSA without co-existent coronary artery disease, and to assess the possible influence of the treatment with Continuous positive airway pressure (CPAP) on these levels. The study population included 200 male participants. The case (n=133) or control (n=67) status was defined by an apnea-hypopnea index of 10 or greater. The hs-cTnT assay was validated as reported previously, with a limit of detection of 3ng/L and an upper reference limit (99th percentile) of 14ng/L. The proportion of subjects with detectable plasma hs-cTnT was higher in patients with OSA than in controls (61 vs 75%, p=0.04). In patients, a significant increase in hs-cTnT levels was observed after an effective treatment with CPAP (7.3±3.4 vs 10.1±4.9ng/L; p<0.01). This study shows that the percentage of subjects with detectable hs-cTnT is associated with the presence of OSA. It also evidences that treatment with CPAP is followed by a rise in hs-cTnT concentrations. It is reasonable to suggest that CPAP therapy might induce a potential degree of cardiac stress, resulting in deleterious consequences for the heart.