Association between BNP and all-cause mortality in critically ill children: a cohort study.

Background: There is evidence that a high level of BNP is associated with poorer outcomes in patients with cardiac diseases, but few data are available concerning BNP and all-cause mortality in pediatric population.

Methods: Using the 2010-2018 pediatric intensive care database, we conducted a retrospective study on patients aged 28 days to 18 years, analyzing post-admission BNP measurements. Through two-piecewise regression to identify inflection points, and multivariable logistic regression, we investigated BNP's association with all-cause mortality. We also developed a multivariable-adjusted restricted cubic spline model to explore BNP's non-linear correlation with mortality.

Results: In a study of 3220 patients, the overall all-cause mortality rate was 6.7%, with rates across BNP quartiles (Q1-Q4) significantly differing, highlighting a notable increase in mortality at higher BNP levels (P < 0.001). Specifically, patients with BNP ≥ 10,170 pg/ml had an adjusted mortality odds ratio (OR) of 2.017 (95% CI 1.265-3.217; P = 0.0032). Analysis confirmed a non-linear relationship between BNP levels and mortality, with log2 BNP associated with increased risk (OR1.28, 95% CI 1.19-1.38; P < 0.001). Subgroup analyses further revealed that very high BNP levels, especially in infants, with lactate ≥2.0 mmol/L, or CKMB ≥ 45 μ/L.

Conclusions: BNP level was associated with all-cause mortality, especially for the patients with BNP ≥ 10,170 pg/ml.

Impact: This study explored the non-linear association between BNP levels and all-cause mortality in the PICU, finding a significant association among patients with BNP levels above 10,170 pg/ml. The study revealed that higher BNP levels are associated with increased mortality in critically ill children, including those with non-cardiac diseases. This research provides new data on a Southern Chinese population, previously unstudied, enriching the existing body of knowledge. While most studies have focused on adult cardiac patients, this research highlights the importance of BNP as a prognostic tool in the PICU, including non-cardiac cases, adding to the literature. This study furnishes novel clinical evidence supporting the monitoring of BNP concentrations within the PICU, aiding in prognostic predictions and the development of tailored treatment plans for patients.