Prevalence and Related Factors of Vitamin D Deficiency in Critically Ill Patients

Background: To identify the prevalence and related factors for vitamin D deficiency in the patients who admitted to the medical intensive care unit (ICU) of a Korean tertiary care hospital. Methods: We retrospectively analyzed the data from ICU patients requiring mechanical ventilation (MV) for a period of > 48 h to identify the prevalence and associated factors for vitamin D deficiency. Vitamin D deficiency was defined as serum 25-hydroxyvitamin D [25(OH)D] level < 20 ng/mL. Results: Among 570 patients admitted to the ICU, 221 were enrolled in the study, 194 in the vitamin D deficient group and 27 in the non-deficient group. Prevalence of vitamin D deficiency in critically ill patients was 87.8%. The patient age was lower in the vitamin D deficient group compared with the non-deficient group (64.4 ± 15.4 vs. 71.0 ± 9.6 years, p = 0.049). A higher acute physiology and chronic health evaluation II (APACHE II) score (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.10-1.37) and chronic illness (OR 3.12, 95% CI 1.08-9.01) were associated with vitamin D deficiency after adjusting for age and body mass index. Clinical outcomes of duration of MV, ICU stay, and 28- and 90-day mortality rates were not significantly different between the vitamin D deficient and nondeficient groups. Conclusions: Vitamin D deficiency was common in critically ill patients, particularly among younger patients. Higher APACHE II score and chronic illness were associated with vitamin D deficiency.