Plasma N-terminal atrial natriuretic peptide predicts hospitalization in patients with heart failure.

The plasma concentration of N-terminal atrial natriuretic peptide (N-ANP) has been shown to be predictive of both clinical status and survival in patients with heart failure. In this analysis the relationship between N-ANP, morbidity and hospitalization time was evaluated in 417 patients with stable, congestive heart failure recruited from an active, outpatient heart failure registry. Hospital admissions along with the duration of stay occurring after the initial N-ANP sampling during the period of data collection were recorded. A total of 755 admissions occurred, accounting for 7917 days' hospitalization. Relative hospitalization times (in-hospital days/observation period) per N-ANP quartiles I-IV were: 1.2 (+/- 2.7)%, 5.5 (+/- 12.2)%, 10.0 (+/- 21.5)% and 20.8 (+/- 34.3)%, respectively. Although N-ANP levels were correlated with age (r = 0.234, p < 0.0001), division by age quartiles did not significantly predict relative hospitalization times. These data indicate that the degree of cardiac endocrine activation and subsequent N-ANP release is related to morbidity in patients with heart failure and that moderate elevation in N-ANP levels is associated with a substantially increased hospitalization time. N-ANP sampling should be of value as a supplement to clinical evaluation in the assessment of the individual patient with this common syndrome.