Vitamin D in infectious complications in critically ill patients with or without COVID-19

Abstract

25-hydroxyvitamin D [25(OH)D] is an important immunomodulator, whose deficiency may aggravate the incidence and outcome of infectious complications in patients admitted to the intensive care unit. The most recognized extra-skeletal action of vitamin D is the regulation of immune function. Host defense against intracellular pathogens depends upon both innate and adaptive immunity. It has been suggested that vitamin D regulates the pro-inflammatory endothelial response to lipopolysaccharide, rendering it a role in the sepsis cascade. Recent studies have indicated that vitamin D deficiency may be associated with worse outcomes in patients with coronavirus disease 2019 (COVID-19), such as more severe disease and higher mortality rates. To this end, clinical trials with vitamin D supplementation are being carried out in an effort to improve COVID-19 outcomes. In this review, we will discuss the role of vitamin D in the immune response, and more specifically its effect on immune cells. Subsequently, we will provide an overview of the studies that have investigated the predictive value of vitamin D in critical illness outcomes, and its therapeutic value as a supplement in critically ill patients. Finally, the emerging role of vitamin D deficiency in COVID-19 infection risk, and worse outcomes will be discussed.

Nutrition in the Intensive Care Unit—A Narrative Review

“…Vitamin D deficiency is highly prevalent across all age groups and countries [ 80 ]. Although vitamin D deficiency was further determined to be associated with greater illness severity (also in patients with COVID 19), a causal relationship between vitamin D deficiency and multiple organ dysfunction has not been established [ 81 , 82 , 83 , 84 ]. Thus, the efficacy of vitamin D as a therapeutic in critically ill patients remains controversial [ 85 ].…”

The association between vitamin D intake with inflammatory and biochemical indices and mortality in critically ill patients with COVID‐19: A case‐control study

“… 13 It was primarily recognized for supporting bone health through calcium homeostasis, but recently, it has drawn attention to its critical role in modulating immune cells and inhibiting the inflammatory response. 14 Previous studies have indicated a relationship between vit D deficiency and some cancers, 15 certain autoimmune, 16 and infectious viral diseases such as SARS, MERS, and Influenza A. 17 In addition, there is evidence that vit D supplementation effectively decreases the level of proinflammatory cytokines such as TNF‐α and IL‐6, stimulates anti‐inflammatory cytokines such as IL‐10 and IL‐12, 3 and reduces the rate of ICU admission of COVID‐19‐infected patients.…”

Bibliometric analysis of the global research status and trends of the association between Vitamin D and infections from 2001 to 2021

“…Recent studies also highlight that vitamin D plays an important role in infectious diseases ( 19 , 20 ). The overall effect of vitamin D deficiency in infections is associated with alteration of the critical immune response such as genetic expression related to antioxidants, cytokine storm, metabolism, and cellular function ( 21 ). However, there are arguments that vitamin D does not do much for infections.…”