Hypercalcemia Without Hypervitaminosis D During Cholecalciferol Supplementation in Critically Ill Patients

Background Vitamin D deficiency during critical illness has been associated with worsened outcomes. Because most critically ill patients with severe traumatic injuries are vitamin D deficient, we investigated the efficacy and safety of cholecalciferol therapy for these patients. Methods Fifty‐three patients (>17 years of age) admitted to the trauma intensive care unit who had a serum 25‐hydroxy vitamin D (25‐OH vit D) concentration <20 ng/mL were given 10,000 IU of cholecalciferol daily. Efficacy was defined as achievement of a 25‐OH vit D of 30–79.9 ng/mL. Safety was evaluated by the presence of hypercalcemia (serum ionized calcium [iCa] >1.32 mmol/L) or hypervitaminosis D (25‐OH vit D >79.9 nmol/L). Patients were monitored for 2 weeks during cholecalciferol therapy. Results : Twenty‐four patients (45%) achieved target 25‐OH vit D. No patients experienced hypervitaminosis D. Hypercalcemia occurred in 40% (n = 21) of patients; 2 patients experienced an iCa >1.49 nmol/L. 25‐OH vit D was significantly greater for those who developed hypercalcemia (37.2 + 11.2 vs 28.4 + 5.6 ng/mL, respectively, P < 0.001) by the second week of cholecalciferol. Of 24 patients who achieved target 25‐OH vit D, 14 (58%) experienced hypercalcemia in contrast to 24% of patients (7 out of 29) who did not achieve target 25‐OH vit D ( P = 0.024). Conclusions Cholecalciferol normalized serum 25‐OH vit D concentrations in less than half of patients yet was associated with a substantial proportion of patients with hypercalcemia without hypervitaminosis D.