Plasma brain natriuretic peptide concentrations and the risk of cardiovascular events and death in general practice

Abstract

The plasma brain natriuretic peptide concentrations (brain natriuretic peptide (BNP) levels) have a prognostic value of mortality and morbidity in patients with chronic heart failure and in a community-based population. However, the prognostic value of BNP levels in outpatients of general practice is not well known. This study investigated the relations of BNP levels to cardiovascular events and death in general practice. This study covered 3123 consecutive outpatients (mean age 59.3±15.3 years; 42% men). BNP levels were measured by immunoradiometric assay (Shionogi) in an occasional sample of each person. During a median follow-up of 5.5 years, 271 patients underwent a cardiovascular event (heart failure 65, coronary heart disease events 63, arrhythmia 26, stroke 96, others 21), 92 died from cardiovascular disease and 227 died from all causes. The patients were stratified into two groups based on a cut-off level of BNP (100 pg/ml). A BNP level ≥100 pg/ml was associated with a hazard ratio (95% confidence interval) of 4.6 (3.5-6.1) for cardiovascular events compared with a BNP <100 pg/ml (p<0.0001), 7.0 (4.5-10.9) for cardiovascular mortality (p<0.0001), 3.2 (2.4-4.2) for all-cause mortality (p<0.0001), 18.8 (11.3-31.1) for heart failure (p<0.0001), 2.5 (1.5-3.9) for stroke (p=0.0002), 5.0 (2.4-11.2) for atrial fibrillation (p<0.0001); however, it was 0.6 (0.2-1.7) for coronary heart disease events (p=0.337). Furthermore, the result of investigation with stratification into six groups based on BNP cut-off levels (20, 40, 100, 200, 500 pg/ml) showed that cardiovascular events, cardiovascular mortality, all-cause mortality, heart failure, stroke, and atrial fibrillation increased stepwise as BNP levels increased (p<0.0001), except for coronary heart disease events (p=0.986). In general practice, BNP levels predicted the risk of cardiovascular events other than coronary heart disease events and of death.