Elevated B-type natriuretic peptide level: use with caution in patients with multiple co-morbidities and presenting with dyspnea

Abstract

Background and aim: While the effect of age, gender, body mass index and renal failure on B-type natriuretic peptide (BNP) has been studied individually in different trials, the influence of all these co-morbidities in patients with dyspnea needs to be evaluated. The objective of our study was to examine the effect of age, gender, obesity and co-morbid conditions on the evaluation of higher BNP levels in patients presenting with dyspnea.

Methods: A total of 382 patients admitted with shortness of breath and suspected to have congestive heart failure were included in the study. The co-morbid conditions studied were pulmonary hypertension, pleural effusion, obesity, renal failure and chronic obstructive pulmonary disease.

Results: The mean BNP levels significantly increased with age. Women tended to have slightly higher mean BNP levels than men, but the differences were not statistically significant. The body mass index had an inverse correlation with the BNP level. Regression analysis demonstrated that the most significant predictors of a higher BNP were the lower left ventricular ejection fraction (OR 6.2: 95% CI 2.74-14.02), renal failure (OR 3.88: 95% CI 1.9-7.91) and pulmonary hypertension (OR 2.28: 95% CI 1.14-4.54).

Conclusion: A lower left ventricular ejection fraction, renal failure and pulmonary hypertension were the most significant predictors of an increased BNP level. Age, gender, obesity and pleural effusion minimally influenced the BNP level and were not significantly predictive of congestive heart failure.