Being Underweight Is an Independent Risk Factor for Poor Outcomes Among Acutely Critically Ill Children

Background: Malnutrition is associated with impaired immune function; thus, nutrition status assessment is crucial in critical care medicine. We aimed to investigate the impact of being underweight or overweight on major sequelae and mortality among healthy children with an intensive care unit admission. Methods: In this retrospective study, 282 patients aged 1 month to 18 years were enrolled on intensive care unit admission between 2011 and 2012. Children were excluded if they had underlying chronic diseases and were transferred to other hospitals or discharged against medical advice. The patients were further categorized into 3 nutrition status groups according to the weight-for-age (W/A) z score. Results: The prevalence rates of being underweight and overweight, based on W/A z scores of ≤–2 and ≥2, were 8.2% and 5.7%, respectively. Patients who were underweight were younger and had a higher rate of mortality, poor outcomes, and longer duration of mechanical ventilation than those with a normal weight. The patients with mortality or major sequelae had significantly higher rates of being underweight, noninfectious diseases and hypotension, and higher Pediatric Index of Mortality 2 (PIM2) score and creatinine level (all P <.01). In multivariate logistic regression interpretation, the W/A z score ≤–2 (95% CI, 2.992–47.508; P <.001) and PIM2 score (95% CI, 1.094–1.413; P =.001) were independent risk factors for a poor outcome. Conclusion: Being underweight and having a PIM2 score on admission were independent risk factors for poor clinical outcomes among critically ill children without underlying diseases.