Vitamin D supplementation in the ICU patient.

PURPOSE OF REVIEW: Recent findings suggest that vitamin D is a marker for outcomes in critical illness. The purpose of this review is to summarize current biological, observational and interventional evidence in the critically ill. RECENT
FINDINGS: Both biological and observational studies support the role of vitamin D deficiency in adverse critical illness outcomes. Interventional trials of critically ill patients show that to improve vitamin D status, high-dose vitamin D3 is required. Critically ill patients have a relatively blunted response to vitamin D supplementation compared to the general outpatient population. Toxicity from high-dose vitamin D in trials in the critically ill has been limited to mild hypercalcemia. Recent evidence suggests that treatment of severely vitamin D-deficient critically ill patients with high-dose vitamin D early in the ICU course may improve mortality.
SUMMARY: Vitamin D deficiency is a potentially modifiable marker for adverse outcomes in critical illness and critical illness survivors. Vitamin D supplementation is inexpensive and appears safe in critical illness trials. A well powered interventional trial is required to determine the definitive answer regarding the role of vitamin D supplementation in the improvement of critical care outcomes. Until such data are available, a cautious approach to correction of vitamin D status in the ICU is warranted.