The Association of Vitamin D Status With Pediatric Critical Illness

OBJECTIVES: Vitamin D is a pleiotropic hormone important for the proper functioning of multiple organ systems. It has been hypothesized that vitamin D deficiency could contribute to or worsen outcomes in critical illness. The study objective was to determine the prevalence of vitamin D deficiency, risk factors for its presence, and potential association with clinically relevant outcomes in critically ill children. METHODS: A prospective cohort study, conducted from 2005 to 2008 in 6 tertiary-care PICUs in Canada. Data and biological samples from 326 critically ill children up to 17 years of age were available for analysis. Total serum 25 hydroxyvitamin D or 25(OH)D was measured by using liquid chromatography-mass spectrometry. RESULTS: The prevalence of 25(OH)D <50 nmol/L was 69% (95% confidence interval, 64–74), and 23% (95% confidence interval, 19–28) for 25(OH)D between 50 to 75 nmol/L. Lower levels were associated with hypocalcemia, catecholamine utilization, and significant fluid bolus administration. Vitamin D deficiency was independently associated with a longer PICU length of stay (+1.92 days, P = .03) and increasing severity of illness as determined by the Pediatric Risk of Mortality score with every additional point increasing the likelihood of being vitamin D deficient by 8% ( P = .005). CONCLUSIONS: This study provides evidence that vitamin D deficiency is both common among critically ill children and associated with greater severity of critical illness. Further research will determine whether targeted vitamin D supplementation or rapid restoration will improve outcome. * Abbreviations: 25(OH)D — : 25-hydroxyvitamin D AIP — : Adrenal Insufficiency in Pediatric Critical Illness Study ALRI — : acute lower respiratory infection CI — : confidence interval IQR — : interquartile range OR — : odds ratio PRISM — : Pediatric Risk of Mortality III