Recent studies in critically ill populations have suggested both adrenal insufficiency (AI) and vitamin D deficiency to be associated with worse clinical outcome. There are multiple mechanisms through which these pleiotropic hormones might synergistically influence critical illness.
The aim of the study was to investigate potential relationships between vitamin D status, adrenal status, and cardiovascular dysfunction in critically ill children.
We conducted a secondary analysis of data from a prospective cohort study.
The study was conducted on 319 children admitted to 6 Canadian tertiary-care pediatric intensive care units.
Vitamin D status was determined through total 25-hydroxyvitamin D (25OHD) levels. AI was defined as a cortisol increment under 9 µg/dL after low-dose cosyntropin. Clinically significant cardiovascular dysfunction was defined as catecholamine requirement during pediatric intensive care unit admission.
Using 3 different thresholds to define vitamin D deficiency, no association was found between vitamin D status and AI. Furthermore, linear regression failed to identify a relationship between 25OHD and baseline or post-cosyntropin cortisol. However, the association between AI and cardiovascular dysfunction was influenced by vitamin D status; compared to children with 25OHD above 30 nmol/L, AI in the vitamin D-deficient group was associated with significantly higher odds of catecholamine use (odds ratio, 5.29 vs 1.63; P = .046).
We did not find evidence of a direct association between vitamin D status and critical illness-related AI. However, our results do suggest that vitamin D deficiency exacerbates the effect of AI on cardiovascular stability in critically ill children.