Does Vitamin D Improve All-cause Mortality in Critically Ill Adults? An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials

INTRODUCTION: Vitamin D deficiency is an amendable risk factor linked to increase in mortality in critically ill patients. The aim of this systematic review was to evaluate if vitamin D supplementation reduced the mortality, and length of stay (LOS) in intensive care units (ICU) and hospitals in critically ill adults including coronavirus disease-2019 (COVID-2019) patients. MATERIALS AND METHODS: We searched the literature using the PubMed, Web of Science, Cochrane and Embase databases until January 13, 2022, for RCTs comparing vitamin D administration to placebo or no treatment in ICUs. The fixed-effect model was used for the primary outcome (all-cause mortality) and the random effect model for secondary objectives (LOS in ICU, hospital, mechanical ventilation). Subgroup analysis included ICU types and high vs low risk of bias. Sensitivity analysis compared severe COVID-19 vs no COVID disease. RESULTS: Eleven RCTs (2,328 patients) were included in the analysis. Pooled analysis of these RCTs, showed no significant difference in all-cause mortality between the vitamin D and placebo groups [odds ratio (OR) 0.93, p = 0.47]. Inclusion of COVID-positive patients did not change the results (OR 0.91, p = 0.37). No significant difference was observed between the vitamin D and placebo groups in LOS in ICU (p = 0.34); hospital (p = 0.40) and mechanical ventilation duration (p = 0.7). In the subgroup analysis, there was no improvement in mortality in medical ICU (p = 0.36) or surgical ICU (p = 0.03). Neither low risk of bias (p = 0.41) nor high risk of bias (p = 0.39) reduced mortality. CONCLUSION: Vitamin D supplementation in the critically ill did not have statistically significant benefits on clinical outcomes in terms of overall mortality, duration of mechanical ventilation, and LOS in ICU and hospital. HOW TO CITE THIS ARTICLE: Kaur M, Soni KD, Trikha A. Does Vitamin D Improve All-cause Mortality in Critically Ill Adults? An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials. Indian J Crit Care Med 2022;26(7):853–862.