Vitamin D status in critically ill patients: the evidence is now bioavailable!

The Association between Preoperative Vitamin D Levels and Postoperative Complications in Patients Undergoing Colorectal Liver Metastasis Surgery

(1) Background: Over the past several years, there has been a renewed interest with regard to the effect of pre-operative vitamin D levels on post-surgical outcomes. Pre-operative vitamin D deficiency has been associated with many negative post-operative outcomes. However, the role of vitamin D in postoperative outcomes in colorectal liver metastasis (CRLM) resection is relatively uninvestigated. Our study investigated the correlation between preoperative vitamin D levels and postoperative complications in patients undergoing resection for CRLM. (2) Methods: We retrospectively examined the post-operative course of 109 patients, who were evaluated based upon preoperative vitamin D levels: the first group had vitamin D levels less than 25 nmol/L (VIT D < 25 nmol/L) (n = 12) vs. the second group who had vitamin D levels equal to or greater than 25 nmol/L (VIT D ≥ 25 nmol/L) (n = 97). (3) Results: Patients with lower pre-operative vitamin D levels (VIT D < 25 nmol/L) had significantly higher rates of blood transfusions (33.3% vs. 10.3%, p = 0.01), post-operative surgical complications (50% vs. 17.5%, p = 0.009), and infectious complications (25% vs. 7.2%, p = 0.04). However, there was no difference in overall survival seen between the two groups. (4) Conclusions: The results of our study indicate that patients with preoperative vitamin D deficiency (defined as preoperative vitamin D levels less than 25 nmol/L) may have an increased risk of postoperative complications in patients undergoing liver surgery for metastatic colorectal cancer.

Vitamin D Status and Potential Therapeutic Options in Critically Ill Patients: A Narrative Review of the Clinical Evidence

Vitamin D covers roles of paramount importance in the regulation of multiple physiological pathways of the organism. The metabolism of vitamin D involves kidney-liver crosstalk and requires an adequate function of these organs, where vitamin D is progressively turned into active forms. Vitamin D deficiency has been widely reported in patients living in the community, being prevalent among the most vulnerable subjects. It has been also documented in many critically ill patients upon admission to the intensive care unit. In this context, vitamin D deficiency may represent a risk factor for the development of life-threatening clinical conditions (e.g., infection and sepsis) and worse clinical outcomes. Several researchers have investigated the impact of vitamin D supplementation showing its feasibility, safety, and effectiveness, although conflicting results have put into question its real benefit in critically ill patients. The existing studies included heterogeneous critically ill populations and used slightly different protocols of vitamin D supplementation. For these reasons, pooling up the results is difficult and not conclusive. In this narrative review, we described vitamin D physiology and the pathophysiology of vitamin D depletion with a specific focus on critically ill patients with liver dysfunction, acute kidney injury, acute respiratory failure, and sepsis.

Factors Associated with Low Vitamin D Status among Older Adults in Kuwait

Low vitamin D levels among older people represent a significant health problem worldwide. This study aimed to examine the factors associated with vitamin D deficiency in older people (aged ≥ 65) in the Kuwaiti population. A cross-sectional study was conducted in seven primary healthcare centers across Kuwait (November 2020 to June 2021). The participants (n = 237) had their serum vitamin D (25(OH)D) concentrations (analyzed using LC-MS) classified as sufficiency 75 nmol/L (30 ng/mL) or deficiency < 75 nmol/L (below 30 ng/mL). The data were collected using self-administered questionnaires and face-to-face interviews with participants in geriatric clinics. Binomial logistic regression analysis was applied to assess factors associated with vitamin D deficiency. Vitamin D deficiency was found to be present in two thirds of the participants (n = 150, 63%), with a higher prevalence of deficiency in participants who did not receive vitamin D supplements, compared to those who did (84% vs. 16%, p = 0.001). The results from the binary logistic regression showed that a low duration of sun exposure (OR = 0.24, 95% C.I. [0.08−0.7], p = 0.011), dark skin pigmentation (OR = 4.46, 95% [1.35−20.49], p = 0.026), and lower caloric intake (OR = 0.9, 95% C.I. [0.85−0.96], p = 0.001) were risk factors for vitamin D deficiency. Furthermore, a significant inverse relationship was found between vitamin D levels and parathyroid hormone (PTH) levels (OR = 1.16, 95% C.I. [1.04−1.31], p = 0.016). These findings support the recommendation that vitamin D supplementation and adequate sunlight exposure are necessary for raising low vitamin D levels in older people in Kuwait.

High Dose Vitamin D3 Supplementation Is Not Associated With Lower Mortality in Critically Ill Patients: A Meta-Analysis of Randomized Control Trials

Background

Vitamin D deficiency is a common condition in critically ill patients. A high dose of vitamin D3 can rapidly restore vitamin D levels. The aim of this meta-analysis was to synthesize the results from up-to-date randomized control trials (RCT) and validate the effect of vitamin D3 in critically ill patients.

Study Methods

Several databases, including PubMed, Web of Science, EMBASE, and the Cochrane Central database, were searched up to December 4th, 2020. All RCTs that investigated the use of a high dose of vitamin D3 in critically ill patients and reported mortality data were included in the meta-analysis. The primary outcome was the mortality truncated to day 28 and day 90.

Results

A total of 10 RCTs enrolling 2058 patients were finally included. The use of a high dose of vitamin D3 in critically ill patients could not decrease the mortality truncated to day 28 (RR 0.93, 95% CI 0.78–1.11, P = 0.43) or day 90 (RR 0.91, 95% CI 0.79–1.05, P = 0.21). A high dose of vitamin D3 could significantly reduce the ventilator days (MD −9.38, 95%CI −13.44 to −5.31, P < 0.001), but there were no statistic difference in length of ICU stay (MD −2.76, 95% CI −6.27 to 0.74, P = 0.12) and hospital stay (MD −2.42, 95% CI −6.21 to 1.36, P = 0.21). No significant difference was observed in adverse events between the vitamin D3 group and the placebo group.

Conclusion

The use of high dose vitamin D3 was not associated with decreased mortality in critically ill patients, but could significantly reduce the ventilator days.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42020179195.

Carbapenem-resistant Acinetobacter baumannii: Colonization, Infection and Current Treatment Options

Carbapenem-resistant Acinetobacter baumannii (CRAB) causes colonization and infection predominantly in hospitalized patients. Distinction between the two is a challenge. When CRAB is isolated from a non-sterile site (soft tissue, respiratory samples, etc.), it probably represents colonization unless clear signs of infection (fever, elevated white blood count, elevated inflammatory markers and abnormal imaging) are present. Treatment is warranted only for true infections. In normally sterile sites (blood, cerebrospinal fluid) the presence of indwelling medical devices (catheters, stents) should be considered when evaluating positive cultures. In the absence of such devices, the isolate represents an infection and should be treated. If an indwelling device is present and there are no signs of active infection, the device should be replaced if possible, and no treatment is required. If there are signs of an active infection the device should be removed or replaced, and treatment should be administered. Current treatments options and clinical data are limited. No agent or combination regimen has been shown to be superior to any other in randomized clinical trials. Ampicillin-sulbactam appears to have the best evidence for initial use. This is probably due to its ability to saturate penicillin-binding proteins 1 and 3 when given in high dose. Tigecycline when used should be given in high dose as well. Polymyxins are a treatment option but are difficult to dose correctly and have significant side effects. Newer treatment options such as eravacycline and cefiderocol have potential; however, currently there are not enough data to support their use as single agents. Combination therapy appears to be the best treatment option and should always include high-dose ampicillin-sulbactam combined with another active agent such as high-dose tigecycline, polymyxins, etc. These infections require a high complexity of skill, and an infectious disease specialist should be involved in the management of these patients.

Association of 25-Hydroxyvitamin D Level with COVID-19-Related in-Hospital Mortality: A Retrospective Cohort Study

BACKGROUND

The primary aim of this study was to compare the 25(OH)D level between patients with COVID-19 and the reference population. The secondary aim was to determine the association of 25(OH)D level with COVID-19-related in-hospital mortality.

METHODS

The COVID-19-positive group comprised 520 hospitalized patients and the reference population comprised 15,789 COVID-19-negative patients. The 25(OH)D level was categorized as vitamin D deficiency (25[OH]D < 20 ng/mL) and severe vitamin D deficiency (25[OH]D < 12 ng/mL).

RESULTS

While the incidence of vitamin D deficiency was similar in both groups, the incidence of severe vitamin D deficiency was higher in patients with COVID-19 than in the reference population (68.3% [n = 355] vs. 55.1% [n = 8,692], p < 0.001). Severe vitamin D deficiency in patients with COVID-19 was higher in the intensive care unit (ICU) group than in the non-ICU group (75.3% [n = 183] vs. 62% [n = 172], p = 0.001). The incidence of severe vitamin D deficiency was 65.4% (n = 280) in survivors and 81.5% (n = 75) in nonsurvivors (p = 0.003). However, multivariable Cox proportional hazard regression analysis showed no relationship between 25(OH)D level and in-hospital mortality. The median survival times of patients with and without severe vitamin D deficiency were not different, as shown by Kaplan-Meier survival analysis.

CONCLUSION

Severe vitamin D deficiency is more common in patients with COVID-19 and may play a significant role in worsening the prognosis of these patients. However, the 25(OH)D level was not observed to effect COVID-19-related in-hospital mortality.

Notable Developments for Vitamin D Amid the COVID-19 Pandemic, but Caution Warranted Overall: A Narrative Review

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel contagion that has infected over 113 million people worldwide. It is responsible for the coronavirus disease (COVID-19), which has cost the lives of 2.5 million people. Ergo, the global scientific community has been scrambling to repurpose or develop therapeutics to treat COVID-19. Dietary supplements and nutraceuticals are among those under consideration due to the link between nutritional status and patient outcomes. Overall, poor vitamin D status seems to be associated with an increased risk of COVID-19. Severely ill COVID-19 patients appear to be deficient or have suboptimal levels of serum 25-hydroxyvitamin D, a measure of vitamin D status. Consequently, vitamin D is now the subject of several prophylactic and therapeutic clinical trials. In this review, the general status of nutraceuticals and dietary supplements amid the pandemic is appraised, with a particular focus on vitamin D. Consumers should be aware of misinformation and unsubstantiated promises for products marketed for COVID-19 protection. However, maintaining a healthy diet and lifestyle will likely maintain health including optimum immune function that may affect patient outcomes. Those who are deficient in key nutrients such as vitamin D should consider lifestyle changes and potentially supplementation in consultation with their physician and/or registered dieticians.

Vitamin D deficiency 2.0: an update on the current status worldwide

Vitamin D testing and the use of vitamin D supplements have increased substantially in recent years. Currently, the role of vitamin D supplementation, and the optimal vitamin D dose and status, is a subject of debate, because large interventional studies have been unable to show a clear benefit (in mostly vitamin D replete populations). This may be attributed to limitations in trial design, as most studies did not meet the basic requirements of a nutrient intervention study, including vitamin D-replete populations, too small sample sizes, and inconsistent intervention methods regarding dose and metabolites. Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] < 50 nmol/L or 20 ng/ml) is associated with unfavorable skeletal outcomes, including fractures and bone loss. A 25(OH)D level of >50 nmol/L or 20 ng/ml is, therefore, the primary treatment goal, although some data suggest a benefit for a higher threshold. Severe vitamin D deficiency with a 25(OH)D concentration below <30 nmol/L (or 12 ng/ml) dramatically increases the risk of excess mortality, infections, and many other diseases, and should be avoided whenever possible. The data on a benefit for mortality and prevention of infections, at least in severely deficient individuals, appear convincing. Vitamin D is clearly not a panacea, and is most likely efficient only in deficiency. Given its rare side effects and its relatively wide safety margin, it may be an important, inexpensive, and safe adjuvant therapy for many diseases, but future large and well-designed studies should evaluate this further. A worldwide public health intervention that includes vitamin D supplementation in certain risk groups, and systematic vitamin D food fortification to avoid severe vitamin D deficiency, would appear to be important. In this narrative review, the current international literature on vitamin D deficiency, its relevance, and therapeutic options is discussed.

Vitamin D in burn-injured patients

Recently, many studies have demonstrated pleotropic effects of vitamin D, including immune modulation and cardiovascular system activity. Sufficient vitamin D concentrations and supplementation of vitamin D may be of benefit in burn-injured patients. Low 25(OH)D has been observed in nearly all pediatric and most adult burn patients. Vitamin D has primarily been studied in pediatric burn patients, focusing on bone marker measurements and the incidence of fractures. The preferred vitamin D dose, formulation, and route of administration remain unknown, and there is limited data on the impact of vitamin D status on clinical outcomes. Further research should focus on determining optimal monitoring strategies, supplementation regimens and clinical outcomes like mortality, length of stay and incidence of sepsis.

Vitamin D and critical illness: what endocrinology can learn from intensive care and vice versa

The prevalence of vitamin D deficiency in intensive care units ranges typically between 40 and 70%. There are many reasons for being or becoming deficient in the ICU. Hepatic, parathyroid and renal dysfunction additionally increases the risk for developing vitamin D deficiency. Moreover, therapeutic interventions like fluid resuscitation, dialysis, surgery, extracorporeal membrane oxygenation, cardiopulmonary bypass and plasma exchange may significantly reduce vitamin D levels. Many observational studies have consistently shown an association between low vitamin D levels and poor clinical outcomes in critically ill adults and children, including excess mortality and morbidity such as acute kidney injury, acute respiratory failure, duration of mechanical ventilation and sepsis. It is biologically plausible that vitamin D deficiency is an important and modifiable contributor to poor prognosis during and after critical illness. Although vitamin D supplementation is inexpensive, simple and has an excellent safety profile, testing for and treating vitamin D deficiency is currently not routinely performed. Overall, less than 800 patients have been included in RCTs worldwide, but the available data suggest that high-dose vitamin D supplementation could be beneficial. Two large RCTs in Europe and the United States, together aiming to recruit >5000 patients, have started in 2017, and will greatly improve our knowledge in this field. This review aims to summarize current knowledge in this interdisciplinary topic and give an outlook on its highly dynamic future.

Severe vitamin D deficiency upon admission in critically ill patients is related to acute kidney injury and a poor prognosis

OBJECTIVES

To evaluate the prevalence of vitamin D deficiency in critically ill patients upon admission to an Intensive Care Unit (ICU) and its prognostic implications.

DESIGN

A single-center, prospective observational study was carried out from January to November 2015. Patients were followed-up on until death or hospital discharge.

SETTING

The department of Critical Care Medicine of a university hospital.

PATIENTS

All adults admitted to the ICU during the study period, without known factors capable of altering serum 25(OH)D concentration.

INTERVENTIONS

Determination of serum 25(OH)D levels within the first 24h following admission to the ICU.

MAIN VARIABLES OF INTEREST

Prevalence and mortality at 28 days.

RESULTS

The study included 135 patients, of which 74% presented deficient serum 25(OH)D levels upon admission to the ICU. Non-survivors showed significantly lower levels than survivors (8.14ng/ml [6.17-11.53] vs. 12ng/ml [7.1-20.30]; P=.04], and the serum 25(OH)D levels were independently associated to mortality (OR 2.86; 95% CI 1.05-7.86; P=.04]. The area under the ROC curve was 0.61 (95% CI 0.51-0.75), and the best cut-off point for predicting mortality was 10.9ng/ml. Patients with serum 25(OH)D<10.9ng/ml also showed higher acute kidney injury rates (13 vs. 29%; P=.02).

CONCLUSION

Vitamin D deficiency is highly prevalent upon admission to the ICU. Severe Vitamin D deficiency (25[OH]D<10.9ng/ml) upon admission to the ICU is associated to acute kidney injury and mortality.

Effect of Cholecalciferol Supplementation on Vitamin D Status and Cathelicidin Levels in Sepsis: A Randomized, Placebo-Controlled Trial

OBJECTIVES

To compare changes in vitamin D status and cathelicidin (LL-37) levels in septic ICU patients treated with placebo versus cholecalciferol.

DESIGN

Randomized, placebo-controlled, trial.

SETTING

Medical and surgical ICUs of a single teaching hospital in Boston, MA.

PATIENTS

Thirty adult ICU patients.

INTERVENTIONS

Placebo (n = 10) versus 200,000 IU cholecalciferol (n = 10) versus 400,000 IU cholecalciferol (n = 10), within 24 hours of new-onset severe sepsis or septic shock.

MEASUREMENTS AND MAIN RESULTS

Blood samples were obtained at baseline (day 1) and on days 3, 5, and 7, to assess total 25-hydroxyvitamin D, as well as vitamin D-binding protein and albumin to calculate bioavailable 25-hydroxyvitamin D. Plasma LL-37 and high-sensitivity C-reactive protein levels were also measured. At baseline, median (interquartile range) plasma 25-hydroxyvitamin D was 17 ng/mL (13-22 ng/mL) and peaked by day 5 in both intervention groups. Groups were compared using Kruskal-Wallis tests. Relative to baseline, on day 5, median change in biomarkers for placebo, 200,000 IU cholecalciferol, and 400,000 IU cholecalciferol groups, respectively, were as follows: 1) total 25-hydroxyvitamin D, 3% (-3% to 8%), 49% (30-82%), and 69% (55-106%) (p < 0.001); 2) bioavailable 25-hydroxyvitamin D, 4% (-8% to 7%), 45% (40-70%), and 96% (58-136%) (p < 0.01); and 3) LL-37: -17% (-9% to -23%), 4% (-10% to 14%), and 30% (23-48%) (p = 0.04). Change in high-sensitivity C-reactive protein levels did not differ between groups. A positive correlation was observed between bioavailable 25-hydroxyvitamin D and LL-37 (Spearman ρ = 0.44; p = 0.03) but not for total 25-hydroxyvitamin D and LL-37.

CONCLUSIONS

High-dose cholecalciferol supplementation rapidly and safely improves 25-hydroxyvitamin D and bioavailable 25-hydroxyvitamin D levels in patients with severe sepsis or septic shock. Changes in bioavailable 25-hydroxyvitamin D are associated with concomitant increases in circulating LL-37 levels. Larger trials are needed to verify these findings and to assess whether optimizing vitamin D status improves sepsis-related clinical outcomes.