Vitamin D Deficiency and Clinical Outcomes in Critically Ill Pediatric Patients: A Systematic Review and Meta-Analysis.

Context: Vitamin D deficiency (VDD) is common in paediatric populations, and its relationship with critical care outcomes warrants further investigation. Objective: The aim is to examine the association between VDD and clinical outcomes in children admitted to the Pediatric Intensive Care Unit (PICU). Methods: This systematic review and meta-analysis investigated the impact of VDD on clinical outcomes in PICU patients. A comprehensive search of Embase, Web of Science, PubMed, and Cochrane databases was conducted. Our primary outcomes were mortality and sepsis incidence, while secondary outcomes included length of stay (LOS), need for inotropic support, and need for and duration of mechanical ventilation. Eligible studies included infants and children aged 1 month to 18 years admitted to the PICU, with baseline 25-hydroxyvitamin D levels measured on admission. Two independent reviewers screened studies, extracted data, and assessed quality. Pooled estimates were obtained using a random-effects model. Results: Out of 2298 screened studies, 27 met the inclusion criteria, comprising 4682 patients. VDD was defined as 25-hydroxyvitamin D levels <20 ng/mL and <30 ng/mL in 22 and 5 studies, respectively. VDD was associated with increased mortality (odds ratio [OR] 2.05, 95% CI 1.21-3.48) and a greater need for inotropic support (OR 2.02, 95% CI 1.43-2.85) than children with vitamin D sufficiency (VDS). No differences were observed between VDD and VDS groups in terms of sepsis incidence postadmission, LOS, or the need for and duration of mechanical ventilation. Conclusion: VDD in critically ill pediatric patients was associated with increased mortality and higher need for inotropic support. Further research is warranted to evaluate the potential benefits of vitamin D supplementation in this high-risk population.