Preoperative Vitamin D Deficiency Is Associated With Postoperative Delirium in Critically Ill Patients

Qiu Y., Sessler D., Chen L., Halvorson S., Cohen B., Bravo M., ...More

JOURNAL OF INTENSIVE CARE MEDICINE, 2021 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume:
  • Publication Date: 2021
  • Doi Number: 10.1177/08850666211021330


Introduction: Postoperative delirium is common, with a reported incidence of 11% to 80% in critically ill patients. Delirium is an independent prognostic factor for poor hospital outcomes. Low vitamin D concentrations are associated with a decline in cognitive function. We therefore tested the hypothesis that low preoperative serum 25-hydroxyvitamin D [25(OH)D] concentrations are associated with postoperative delirium in critically ill patients. Method: We conducted a retrospective analysis of adults in a surgical intensive care unit for at least 48 hours immediately after non-cardiac and non-neurosurgical operations at Cleveland Clinic between 2013 and 2018. Delirium was assessed by trained nurses using CAM-ICU twice daily for the initial 5 postoperative days. Any positive value was considered evidence of delirium. We assessed the association between 25(OH)D concentrations within a year before surgery and the incidence of postoperative delirium using logistic regression, adjusted for potential confounders. A linear spline term with a knot at 30 ng/ml, the threshold for normal 25(OH)D concentration, was added to accommodate a nonlinear relationship between 25(OH)D concentrations and delirium. Results: We included 632 patients, who had a mean (SD) 25(OH)D concentration of 25 (15) ng/ml; 55% (346/632) experienced delirium. We observed an adjusted odds ratio of 1.4 (95% CI: [1.1, 1.8], P = 0.01) for delirium per 10 ng/ml decrease in 25(OH)D concentrations when patients' 25(OH)D concentrations were less than 30 ng/ml. In patients whose 25(OH)D concentrations were at least 30 ng/ml, the adjusted odds ratio was 0.9 (95% CI: [0.7, 1.1], P = 0.36). Conclusion: Preoperative 25(OH)D concentrations are associated with postoperative delirium in patients whose concentrations are below the normal threshold, but not at concentrations >= 30 ng/ml. A trial will be needed to determine whether the relationship is causal, and whether vitamin D supplementation before surgery might reduce the incidence of delirium.