Biomarker panel in sleep apnea patients after an acute coronary event

Abstract

Background: Acute coronary syndrome (ACS) is a major cause of death and closely related with obstructive sleep apnea (OSA). Our hypothesis is that several cardiovascular-related biomarkers could have a differential prognostic value for ACS severity in patients with OSA, and could also help (individually or combined) in the detection of OSA in patients after a coronary event. Methods: Up to 361 consecutive individuals admitted due to ACS were included in the study. All of them were evaluated for ACS severity (Killip score, number of diseased vessels, ejection fraction) and further classified as OSA or non-OSA. Medical records were registered and eleven blood biomarkers were measured, including heart-type fatty acid-binding globulin, N-terminal pro-brain natriuretic peptide, matrix metalloproteinase-9 (MMP9), placental growth factor (PlGF) and high-sensitivity C-reactive protein. Odds ratios of every biomarker for ACS severity-related parameters were calculated and adjusted for age, gender, body-mass index (BMI), hypertension, diabetes, smoking and drinking. The use of clinical measures and biomarkers for the diagnosis of OSA in ACS patients was evaluated both alone and combined using ROC curves. Results: Several biomarkers showed a significant association with ACS severity, which remained after adjusting for OSA and other potentially confounding variables. The mathematical combination of age, BMI, PlGF and MMP9 showed an area under the ROC curve (AUC) for OSA identification of 0.741, which was greater than any individual parameter or combination assessed: AUC(BMI):0.687, AUC(age):0.576, AUC(PlGF):0.584, AUC(MMP9):0.555. Conclusions: The usefulness of biomarkers in the assessment of ACS severity was independent of OSA and the other variables evaluated. In patients admitted after a coronary event, the combination of clinical measures and biomarkers showed a significant discriminating power for the detection of OSA. Clinical trial registration: NCT01335087 (clinicaltrials.gov).