Comparison of Serum Vitamin D Status in Critically ill and Non-critically ill Children and its Relationship with Illness Severity and Clinical Outcomes: A Case–Control Study

Abstract

Background: The role of vitamin D in immune function is well-established in adults, but remains unclear in children. Objectives: We aimed to determine the prevalence of vitamin D deficiency in critically ill versus non-critically ill children and the correlation between vitamin D level with illness severity and clinical outcomes. Materials and Methods: This was a hospital-based, case–control study involving 35 critically ill and 35 non-critically ill children aged 1 month to 18 years. Serum Vitamin D levels were determined and categorized. Severity of illness of the critically ill group was classified based on calculated modified Sequential Organ Failure Assessment scores, and participants were followed-up until discharge or demise. Results: Median values of vitamin D levels in the critically ill (78.2 ng/mL) and the non-critically ill (60.3 ng/mL) were significantly different (P = 0.003). None of the children in both groups were found to be vitamin D–deficient. There was no significant correlation between vitamin D levels and severity of illness (P = 0.69). Children with overdose, non-toxic levels were less likely to die when compared with those in the optimal range of vitamin D, with odds ratio (95%CI) 0.05 (0.004–0.65). Conclusion: Serum vitamin D deficiency was uncommon in our cohort of critically ill children and was not related to severity of illness, mortality, or length of hospital stay. Although routine vitamin D assessment and supplementation has been proposed to boost the immune system of critically ill adults to help them recover faster, it may not be of added benefit in children.

Keywords

• clinical outcome
• critically ill children
• illness severity
• vitamin d deficiency