N-terminal pro-B-type natriuretic peptide and long-term mortality in stable coronary heart disease

Abstract

Background: The level of the inactive N-terminal fragment of pro-brain (B-type) natriuretic peptide (BNP) is a strong predictor of mortality among patients with acute coronary syndromes and may be a strong prognostic marker in patients with chronic coronary heart disease as well. We assessed the relationship between N-terminal pro-BNP (NT-pro-BNP) levels and long-term mortality from all causes in a large cohort of patients with stable coronary heart disease.

Methods: NT-pro-BNP was measured in baseline serum samples from 1034 patients referred for angiography because of symptoms or signs of coronary heart disease. The rate of death from all causes was determined after a median follow-up of nine years.

Results: At follow-up, 288 patients had died. The median NT-pro-BNP level was significantly lower among patients who survived than among those who died (120 pg per milliliter [interquartile range, 50 to 318] vs. 386 pg per milliliter [interquartile range, 146 to 897], P<0.001). Patients with NT-pro-BNP levels in the highest quartile were older, had a lower left ventricular ejection fraction (LVEF) and a lower creatinine clearance rate, and were more likely to have a history of myocardial infarction, clinically significant coronary artery disease, and diabetes than patients with NT-pro-BNP levels in the lowest quartile. In a multivariable Cox regression model, the hazard ratio for death from any cause for the patients with NT-pro-BNP levels in the fourth quartile as compared with those in the first quartile was 2.4 (95 percent confidence interval, 1.5 to 4.0; P<0.001); the NT-pro-BNP level added prognostic information beyond that provided by conventional risk factors, including the patient's age; sex; family history with respect to ischemic heart disease; the presence or absence of a history of myocardial infarction, angina, hypertension, diabetes, or chronic heart failure; creatinine clearance rate; body-mass index; smoking status; plasma lipid levels; LVEF; and the presence or absence of clinically significant coronary artery disease on angiography.

Conclusions: NT-pro-BNP is a marker of long-term mortality in patients with stable coronary disease and provides prognostic information above and beyond that provided by conventional cardiovascular risk factors and the degree of left ventricular systolic dysfunction.