Heart-type fatty acid binding protein as a prognostic factor in patients with exacerbated chronic obstructive pulmonary disease

Background

The designation of some cardiac-specific proteins as prognostic biomarkers in chronic obstructive pulmonary disease (COPD) exacerbations suggest that the process of exacerbation involves cardiomyocyte injury. Among these cardiac biomarkers, heart-type fatty acid binding protein (h-FABP) is considered a very sensitive diagnostic marker for cardiomyocyte injury and a prognostic marker in chronic heart failure. However, the prognostic usefulness of h-FABP in patients with COPD remains unclear.

Methods

Sixty-six patients were enrolled in this study. Subjects who recovered from COPD exacerbation and were discharged without needing home oxygen therapy were defined as the improved group. Those who died of the COPD exacerbations, were discharged but needed home oxygen therapy, or were transferred to a rehabilitation hospital for respiratory failure and the remaining aftereffects of exacerbation were defined as the unimproved group.

Results

The improved and unimproved groups included 54 and 12 subjects, respectively. Compared with the improved group, the unimproved group had significantly higher white blood cell counts and alanine aminotransferase, lactate dehydrogenase, blood urea nitrogen (BUN), uric acid, potassium, and h-FABP levels, and significantly lower total protein and total cholesterol levels and estimated glomerular filtration rates, either at admission or during the early morning within 24 h after admission. A multivariate analysis revealed that higher serum h-FABP and potassium levels were independently predictive of a poor prognosis following a COPD exacerbation, and a receiver operating characteristic curve analysis yielded a cutoff of 4.5 ng/ml for predicting lack of improvement.

Conclusion

H-FABP may predict the outcomes of COPD exacerbation.