Abstract 3613: Anemia as an Independent Predictor of Elevated Pro-BNP Levels in Patients without Evidence of Heart Failure and Normal Renal Function
Introduction: Pro-BNP has emerged as a primary tool for diagnosing congestive heart failure (CHF). Studies have shown that the level of pro-BNP is affected by renal insufficiency (RI) and age, independent of the diagnosis of CHF. There is some suggestion that anemia may also independently effect pro-BNP levels.
Objective: To assess the effect of anemia on pro-BNP independent of CHF.
Methods: We evaluated 746 consecutive patients presenting to the ER on which pro-BNP was ordered on clinical grounds. All patients underwent a TTE and clinical evaluation for CHF. Patients were included if they had a normal TTE (normal systolic function, mitral inflow pattern and LV wall thickness) and no evidence of CHF based on clinical evaluation. Patients were excluded if they had RI (creatinine ≥ 2 mg/dl) or a diagnosis of sepsis. Anemia was defined using the W.H.O. definition of hgb <13 g/dl for males and < 12 g/dl for females.
Results: Of the 746 consecutive patients, 218 patients (138 anemia, 80 no anemia) met the inclusion criteria. There was a markedly significant difference between pro-BNP levels based on the W.H.O. diagnosis of anemia. Patients with anemia had a mean pro-BNP of 4,735 pg/ml compared to 1,230 pg/ml in patients without anemia (p = 0.0001). Stepwise regression model determined that this significant difference is independent of age. Linear regression analysis comparing hgb with log pro-BNP was also statistically significant (r = 0.395; p = 0.0001).
Conclusion: This study suggests that pro-BNP is associated with anemia independent of CHF, RI, sepsis and age.