Background: We examined whether secretoneurin (SN), a biomarker associated with cardiomyocyte Ca(2+) handling, provides prognostic information in patients with acute respiratory failure (ARF).
Methods: We included 490 patients with ARF, defined as ventilatory support >6 h, with blood samples available on admission to the intensive care unit (ICU). SN concentrations were measured by RIA.
Results: A total of 209 patients (43%) were hospitalized with cardiovascular (CV)-related ARF, and 90-day mortality rates were comparable between CV- and non-CV-related ARF (n = 281): 31% vs 24%, P = 0.11. Admission SN concentrations were higher in nonsurvivors than in survivors in both CV-related (median 148 [quartile 1-3, 117-203] vs 108 [87-143] pmol/L, P < 0.001) and non-CV-related ARF (139 [115-184] vs 113 [91-139] pmol/L, P < 0.001). In patients with CV-related ARF, SN concentrations on ICU admission were associated with 90-day mortality [odds ratio (OR) 1.97 (95% CI, 1.04-3.73, P = 0.04)] after adjusting for established risk indices, including N-terminal-pro-B-type natriuretic peptide (NT-proBNP) concentrations. SN also improved patient classification in CV-related ARF as assessed by the net reclassification index: 0.32 (95% CI, 0.04-0.59), P = 0.03. The area under the curve (AUC) of SN to predict mortality in patients with CV-related ARF was 0.72 (95% CI, 0.65-0.79), and the AUC of NT-proBNP was 0.64 (0.56-0.73). In contrast, SN concentrations on ICU admission did not provide incremental prognostic value to established risk indices in patients with non-CV-related ARF, and the AUC was 0.67 (0.60-0.75).
Conclusions: SN concentrations measured on ICU admission provided incremental prognostic information to established risk indices in patients with CV-related ARF, but not in patients with non-CV-related ARF.
© 2016 American Association for Clinical Chemistry.