Vitamin D deficiency and length of pediatric intensive care unit stay: a prospective observational study

Background: Due to the limited data available in the pediatric population and lack of interventional studies to show that administration of vitamin D indeed improves clinical outcomes, opinion is still divided as to whether it is just an innocent bystander or a marker of severe disease. Our objective was therefore to estimate the prevalence of vitamin D deficiency in children admitted to intensive care unit (ICU) and to examine its association with duration of ICU stay and other key clinical outcomes. Methods: We prospectively enrolled children aged 1 month-17 years admitted to the ICU over a period of 8 months (n = 101). The primary objectives were to estimate the prevalence of vitamin D deficiency (serum 25 (OH) < 20 ng/mL) at 'admission' and to examine its association with length of ICU stay. Results: The prevalence of vitamin D deficiency was 74 % (95 % CI: 65-88). The median (IQR) duration of ICU stay was significantly longer in 'vitamin D deficient' children (7 days; 2-12) than in those with 'no vitamin D deficiency' (3 days; 2-5; p = 0.006). On multivariable analysis, the association between length of ICU stay and vitamin D deficiency remained significant, even after adjusting for key baseline variables, diagnosis, illness severity (PIM-2), PELOD, and need for fluid boluses, ventilation, inotropes and mortality [adjusted mean difference (95 % CI): 3.5 days (0.50-6.53); p = 0.024]. Conclusions: We observed a high prevalence of vitamin D deficiency in critically ill children in our study population. Vitamin D deficient children had a longer duration of ICU stay as compared to others.