Objectives: Co-morbid conditions including risk factors for cardiovascular diseases and left ventricular dysfunction are common in patients with chronic obstructive pulmonary disease (COPD). This study assessed the incidence of cardiac troponin I (cTnI) elevation, a specific marker for cardiac injury, and its prognostic significance during severe exacerbation of COPD.
Design: Prospective cohort study.
Setting: Two intensive care units.
Participants: Seventy-one consecutive patients admitted for severe exacerbation of COPD.
Measurements and results: Cardiac troponin I was assayed in blood samples obtained on admission and 24 h later (Stratus II immunoassay analyser, Dade International). Levels above 0.5 ng/ml were considered positive. The following data were recorded prospectively: clinical symptoms, co-morbidities, cause of the exacerbation, diagnostic procedures and treatment, general severity score (SAPS II) and in-hospital outcome. CTnI was positive in 18% of patients (95% confidence interval (CI(95)), 11-29%), with a median value at 1.00 ng/ml; CI(95 )(0.60-1.70). Eighteen patients died in the hospital (25%; CI(95), 17-37%). Only cTnI (adjusted odds ratio (ORa), 6.52; CI(95),1.23-34.47) and SAPS II 24 h after admission (ORa, 1.07; CI(95), 1.01-1.13) were independent predictors of in-hospital mortality.
Conclusion: Elevated cTnI is a strong and independent predictor of in-hospital death in patients admitted for acutely exacerbated COPD.