Pregnancy and COVID-19: The Possible Contribution of Vitamin D.

BACKGROUND: Vitamin D deficiency has been associated with the severity of COVID-19. The role of vitamin D in pregnant women with COVID-19 has been poorly investigated to date. The aim of this study was to evaluate the influence of vitamin D in affecting some clinical features in pregnancy between SARS-CoV-2 positive and negative patients. METHODS: Vitamin D pathway related polymorphisms and 25-hydroxyvitamin D levels were quantified in pregnant women followed from the first to the third trimester of pregnancy. Vitamin D deficiency was considered with values ≤ 30 ng/mL. RESULTS: In total, 160 women were enrolled: 23 resulted positive for at least one SARS-CoV-2 related test (molecular swab or antibody tests). Vitamin D-associated polymorphisms were able to affect vitamin D levels in SARS-CoV-2 negative and positive subjects: remarkably, all the VDR TaqICC genotype patients were negative for SARS-CoV-2. In a sub-population (118 patients), vitamin D levels correlated with pregnancy-related factors, such as alpha-fetoprotein levels. Third-trimester vitamin D levels were lower in preterm births compared to full-term pregnancy: this trend was highlighted for SARS-CoV-2 positive patients. CONCLUSIONS: This is the first study demonstrating a role of vitamin D in affecting the clinical characteristics of pregnant women during the COVID-19 era. Further studies in larger and different cohorts of patients are required to confirm these findings.

Pre-infection 25-hydroxyvitamin D3 levels and association with severity of COVID-19 illness.

OBJECTIVE: Studies have demonstrated a potential correlation between low vitamin D status and both an increased risk of infection with SARS-CoV-2 and poorer clinical outcomes. This retrospective study examines if, and to what degree, a relationship exists between pre-infection serum 25-hydroxyvitamin D (25(OH)D) level and disease severity and mortality due to SARS-CoV-2. PARTICIPANTS: The records of individuals admitted between April 7th, 2020 and February 4th, 2021 to the Galilee Medical Center (GMC) in Nahariya, Israel, with positive polymerase chain reaction (PCR) tests for SARS-CoV-2 (COVID-19) were searched for historical 25(OH)D levels measured 14 to 730 days prior to the positive PCR test. DESIGN: Patients admitted to GMC with COVID-19 were categorized according to disease severity and level of 25(OH)D. An association between pre-infection 25(OH)D levels, divided between four categories (deficient, insufficient, adequate, and high-normal), and COVID-19 severity was ascertained utilizing a multivariable regression analysis. To isolate the possible influence of the sinusoidal pattern of seasonal 25(OH)D changes throughout the year, a cosinor model was used. RESULTS: Of 1176 patients admitted, 253 had records of a 25(OH)D level prior to COVID-19 infection. A lower vitamin D status was more common in patients with the severe or critical disease (<20 ng/mL [87.4%]) than in individuals with mild or moderate disease (<20 ng/mL [34.3%] p < 0.001). Patients with vitamin D deficiency (<20 ng/mL) were 14 times more likely to have severe or critical disease than patients with 25(OH)D ≥40 ng/mL (odds ratio [OR], 14; 95% confidence interval [CI], 4 to 51; p < 0.001). CONCLUSIONS: Among hospitalized COVID-19 patients, pre-infection deficiency of vitamin D was associated with increased disease severity and mortality.

Is There a Crucial Link Between Vitamin D Status and Inflammatory Response in Patients With COVID-19?

Background: Hypovitaminosis D has been suggested to play a possible role in coronavirus disease 2019 (COVID-19) infection. Methods: The aim of this study is to analyze the relationship between vitamin D status and a biochemical panel of inflammatory markers in a cohort of patients with COVID-19. A secondary endpoint was to evaluate the correlation between 25OHD levels and the severity of the disease. Ninety-three consecutive patients with COVID-19-related pneumonia were evaluated from March to May 2020 in two hospital units in Pisa, in whom biochemical inflammatory markers, 25OHD levels, P/F ratio at nadir during hospitalization, and complete clinical data were available. Results: Sixty-five percent of patients presented hypovitaminosis D (25OHD ≤ 20 ng/ml) and showed significantly higher IL-6 [20.8 (10.9-45.6) vs. 12.9 (8.7-21.1) pg/ml, p = 0.02], CRP [10.7 (4.2-19.2) vs. 5.9 (1.6-8.1) mg/dl, p = 0.003], TNF-α [8.9 (6.0-14.8) vs. 4.4 (1.5-10.6) pg/ml, p = 0.01], D-dimer [0.53 (0.25-0.72) vs. 0.22 (0.17-0.35) mg/l, p = 0.002], and IL-10 [3.7 (1.8-6.9) vs. 2.3 (0.5-5.8) pg/ml, p = 0.03]. A significant inverse correlation was found between 25OHD and all these markers, even adjusted for age and sex. Hypovitaminosis D was prevalent in patients with severe ARDS, compared with the other groups (75% vs. 68% vs. 55%, p < 0.001), and 25OHD levels were lower in non-survivor patients. Conclusions: The relationship between 25OHD levels and inflammatory markers suggests that vitamin D status needs to be taken into account in the management of these patients. If vitamin D is a marker of poor prognosis or a possible risk factor with beneficial effects from supplementation, this still needs to be elucidated.

Monthly Increase in Vitamin D Levels upon Supplementation with 2000 IU/Day in Healthy Volunteers: Result from "Integriamoci", a Pilot Pharmacokinetic Study.

Vitamin D (VD) is a calcium- and phosphate-controlling hormone used to treat bone disorders; yet, several other effects are progressively emerging. VD deficiency is highly prevalent worldwide, with suboptimal exposure to sunlight listed among the leading causes: oral supplementation with either cholecalciferol or calcitriol is used. However, there is a scarcity of clinical studies investigating how quickly VD concentrations can increase after supplementation. In this pilot study, the commercial supplement ImmuD3 (by Erboristeria Magentina®) was chosen as the source of VD and 2000 IU/day was administered for one month to 21 healthy volunteers that had not taken any other VD supplements in the previous 30 days. Plasma VD levels were measured through liquid chromatography coupled to tandem mass spectrometry after 7, 14, and 28 days of supplementation. We found that 95% of the participants had insufficient VD levels at baseline (<30 ng/mL; median 23.72 ng/mL; IQR 18.10-26.15), but after 28 days of supplementation, this percentage dropped to 62% (median 28.35 ng/mL; IQR 25.78-35.20). The median increase in VD level was 3.09 ng/mL (IQR 1.60-5.68) after 7 days and 8.85 ng/mL (IQR 2.85-13.97F) after 28 days. This study suggests the need for continuing VD supplementation and for measuring target level attainment.

Vitamin D Levels Are Associated With Blood Glucose and BMI in COVID-19 Patients, Predicting Disease Severity.

CONTEXT: A high prevalence of vitamin D (VD) deficiency in COVID-19 patients has been reported and hypothesized to increase COVID-19 severity likely because of its negative impact on immune and inflammatory responses. Furthermore, clear associations between hypovitaminosis D and fat body mass excess and diabetes, factors associated with COVID-19 severity, have been widely recognized. OBJECTIVE: The aim of this study was to evaluate in COVID-19 patients the relationship between VD levels and inflammatory response, body mass index (BMI), blood glucose (GLU), and disease severity. METHODS: Patients admitted to San Raffaele-Hospital for COVID-19 were enrolled in this study, excluding those with comorbidities and therapies influencing VD metabolism. 25-Hydroxyvitamin D levels, plasma GLU levels, BMI, and inflammatory parameters were evaluated at admission. RESULTS: A total of 88 patients were included. Median VD level was 16.3 ng/mL and VD deficiency was found in 68.2% of patients. VD deficiency was found more frequently in male patients and in those affected by severe COVID-19. Regression analyses showed a positive correlation between VD and PaO2/FiO2 ratio, and negative correlations between VD and plasma GLU, BMI, neutrophil/lymphocyte ratio, C-reactive protein, and interleukin 6. Patients with both hypovitaminosis D and diabetes mellitus, as well those with hypovitaminosis D and overweight, were more frequently affected by a severe disease with worse inflammatory response and respiratory parameters, compared to those without or just one of these conditions. CONCLUSION: We showed, for the first-time, a strict association of VD levels with blood GLU and BMI in COVID-19 patients. VD deficiency might be a novel common pathophysiological mechanism involved in the detrimental effect of hyperglycemia and adiposity on disease severity.

Seroprevalence of Toxoplasma gondii, Rubella, Group A Streptococcus, CMV and HSV-1 in COVID-19 Patients with Vitamin D Deficiency.

<b>Background and Objective:</b> In recent years, respiratory tract viral infections have caused many pandemics that impact the whole world. To investigate the seropositivity of <i>Toxoplasma gondii</i>, rubella, CMV, HSV-1 and group A <i>Streptococcus</i> in recovered COVID-19 patients and correlate these findings with vitamin D levels. <b>Materials and Methods:</b> A total of 417 COVID-19 patients with diarrhoea were enrolled in this study. Vitamin D and seroprevalence for <i>Toxoplasma gondii</i>, rubella, CMV, HSV-1 and group A <i>Streptococcus</i> were evaluated and correlated. <b>Results:</b> It was found that recent infection in COVID-19 patients with HSV-1, rubella, <i>Toxoplasma</i> and CMV, respectively. IgG was detected indicating the development of adaptive immunity with all microbes. <b>Conclusion:</b> Current study detected a correlation between vitamin D levels and HSV-1 and no correlation between this infection and vitamin D deficiency with the other microbes.

Vitamin D Serum Levels in Subjects Tested for SARS-CoV-2: What Are the Differences among Acute, Healed, and Negative COVID-19 Patients? A Multicenter Real-Practice Study.

Vitamin D might play a role in counteracting COVID-19, albeit strong evidence is still lacking in the literature. The present multicenter real-practice study aimed to evaluate the differences of 25(OH)D3 serum levels in adults tested for SARS-CoV-2 (acute COVID-19 patients, subjects healed from COVID-19, and non-infected ones) recruited over a 6-month period (March-September 2021). In a sample of 117 subjects, a statistically significant difference was found, with acute COVID-19 patients demonstrating the lowest levels of serum 25(OH)D3 (9.63 ± 8.70 ng/mL), significantly lower than values reported by no-COVID-19 patients (15.96 ± 5.99 ng/mL, p = 0.0091) and healed COVID-19 patients (11.52 ± 4.90 ng/mL, p > 0.05). Male gender across the three groups displayed unfluctuating 25(OH)D3 levels, hinting at an inability to ensure adequate levels of the active vitamin D3 form (1α,25(OH)2D3). As a secondary endpoint, we assessed the correlation between serum 25(OH)D3 levels and pro-inflammatory cytokine interleukin-6 (IL-6) in patients with extremely low serum 25(OH)D3 levels (<1 ng/mL) and in a subset supplemented with 1α,25(OH)2D3. Although patients with severe hypovitaminosis-D showed no significant increase in IL-6 levels, acute COVID-19 patients manifested high circulating IL-6 at admission (females = 127.64 ± 22.24 pg/mL, males = 139.28 ± 48.95 ng/mL) which dropped drastically after the administration of 1α,25(OH)2D3 (1.84 ± 0.77 pg/mL and 2.65 ± 0.92 ng/mL, respectively). Taken together, these findings suggest that an administration of 1α,25(OH)2D3 might be helpful for treating male patients with an acute COVID-19 infection. Further studies on rapid correction of vitamin D deficiency with fast acting metabolites are warranted in COVID-19 patients.

Vitamin D-related polymorphisms and vitamin D levels as risk biomarkers of COVID-19 disease severity.

Vitamin D is a fundamental regulator of host defences by activating genes related to innate and adaptive immunity. Previous research shows a correlation between the levels of vitamin D in patients infected with SARS-CoV-2 and the degree of disease severity. This work investigates the impact of the genetic background related to vitamin D pathways on COVID-19 severity. For the first time, the Portuguese population was characterized regarding the prevalence of high impact variants in genes associated with the vitamin D pathways. This study enrolled 517 patients admitted to two tertiary Portuguese hospitals. The serum concentration of 25 (OH)D, was measured in the hospital at the time of patient admission. Genetic variants, 18 variants, in the genes AMDHD1, CYP2R1, CYP24A1, DHCR7, GC, SEC23A, and VDR were analysed. The results show that polymorphisms in the vitamin D binding protein encoded by the GC gene are related to the infection severity (p = 0.005). There is an association between vitamin D polygenic risk score and the serum concentration of 25 (OH)D (p = 0.04). There is an association between 25 (OH)D levels and the survival and fatal outcomes (p = 1.5e-4). The Portuguese population has a higher prevalence of the DHCR7 RS12785878 variant when compared with its prevalence in the European population (19% versus 10%). This study shows a genetic susceptibility for vitamin D deficiency that might explain higher severity degrees in COVID-19 patients. These results reinforce the relevance of personalized strategies in the context of viral diseases.Trial registration: NCT04370808.

Vitamin D association with the renin angiotensin system in polycystic ovary syndrome.

Vitamin D deficiency is a negative endocrine renin-angiotensin system (RAS) modulator and PCOS women are often vitamin D deficient, leading to RAS overactivation in PCOS. A cross-sectional study was performed in 99 PCOS and 68 control women who presented sequentially. Circulating plasma levels of RAS proteins (Angiotensin-converting enzyme 2 (ACE2), renin and angiotensinogen) were measured by Slow Off-rate Modified Aptamer (SOMA)-scan and 25-hydroxyvitamin D [25(OH)D] was measured by tandem mass spectroscopy. The RAS system was found to be overactivated in the PCOS women compared to non-PCOS control women with increased renin and decreased angiotensinogen (p < 0.05); 25-hydroxyvitamin D was also significantly lower in the PCOS group (p < 0.0001). In PCOS women, plasma renin was increased in vitamin D deficient and insufficient groups compared with the vitamin D sufficient group (p < 0.005), but did not differ across non-PCOS control subgroups. In non-PCOS controls, plasma ACE2 decreased from vitamin D insufficiency to deficiency (p < 0.05). Angiotensinogen was not different across the vitamin D sufficiency, insufficiency and deficiency strata for either PCOS or non-PCOS controls. These data show that RAS activation through increased plasma renin levels was seen in vitamin D insufficient and deficient PCOS subjects compared to non-PCOS control women. In addition, decreased plasma ACE2 levels were seen in vitamin D deficiency in non-PCOS controls, which may predispose these vitamin D deficient subjects to increased cardiovascular risk and susceptibility to infectious agents such as COVID-19 where this is a risk factor.

The Association between Vitamin D and Zinc Status and the Progression of Clinical Symptoms among Outpatients Infected with SARS-CoV-2 and Potentially Non-Infected Participants: A Cross-Sectional Study.

Vitamin D and zinc are important components of nutritional immunity. This study compared the serum concentrations of 25-hydroxyvitamin D (25(OH)D) and zinc in COVID-19 outpatients with those of potentially non-infected participants. The association of clinical symptoms with vitamin D and zinc status was also examined. A checklist and laboratory examination were applied to collect data in a cross-sectional study conducted on 53 infected outpatients with COVID-19 and 53 potentially non-infected participants. Serum concentration of 25(OH)D were not significantly lower in patients with moderate illness (19 ± 12 ng/mL) than patients with asymptomatic or mild illness (29 ± 18 ng/mL), with a trend noted for a lower serum concentration of 25(OH)D in moderate than asymptomatic or mild illness patients (p = 0.054). Infected patients (101 ± 18 µg/dL) showed a lower serum concentration of zinc than potentially non-infected participants (114 ± 13 µg/dL) (p = 0.01). Patients with normal (odds ratio (OR), 0.19; p ≤ 0.001) and insufficient (OR, 0.3; p = 0.007) vitamin D status at the second to seventh days of disease had decreased OR of general symptoms compared to patients with vitamin D deficiency. This study revealed the importance of 25(OH)D measurement to predict the progression of general and pulmonary symptoms and showed that infected patients had significantly lower zinc concentrations than potentially non-infected participants.

Impact of vitamin D on the course of COVID-19 during pregnancy: A case control study.

OBJECTIVE: We aimed to evaluate the vitamin D status of pregnant women with COVID-19, and the association between vitamin D level and severity of COVID-19. METHODS: In this case control study, 159 women with a single pregnancy and tested positive for SARS-CoV-2, and randomly selected 332 healthy pregnant women with similar gestational ages were included. COVID-19 patients were classified as mild, moderate, and severe. Vitamin D deficiency was defined as 25-hydroxycholecalciferol <20 ng/mL (50 nmol/L), and 25-OH D vitamin <10 ng/mL was defined as severe vitamin D deficiency, also 25-OH D vitamin level between 20-29 ng/mL (525-725 nmol/L) was defined as vitamin D insufficiency. RESULTS: Vitamin D levels of the pregnant women in the COVID-19 group (12.46) were lower than the control group (18.76). 25-OH D vitamin levels of those in the mild COVID-19 category (13.69) were significantly higher than those in the moderate/severe category (9.06). In terms of taking vitamin D supplementation, there was no statistically significant difference between the groups. However, it was observed that all of those who had severe COVID-19 were the patients who did not take vitamin D supplementation. CONCLUSION: The vitamin D levels are low in pregnant women with COVID-19. Also, there is a significant difference regarding to vitamin D level and COVID-19 severity in pregnant women. Maintenance of adequate vitamin D level can be useful as an approach for the prevention of an aggressive course of the inflammation induced by this novel coronavirus in pregnant women.

Vitamin D and Platelets: A Menacing Duo in COVID-19 and Potential Relation to Bone Remodeling.

Global data correlate severe vitamin D deficiency with COVID-19-associated coagulopathy, further suggesting the presence of a hypercoagulable state in severe COVID-19 patients, which could promote thrombosis in the lungs and in other organs. The feedback loop between COVID-19-associated coagulopathy and vitamin D also involves platelets (PLTs), since vitamin D deficiency stimulates PLT activation and aggregation and increases fibrinolysis and thrombosis. Vitamin D and PLTs share and play specific roles not only in coagulation and thrombosis but also during inflammation, endothelial dysfunction, and immune response. Additionally, another 'fil rouge' between vitamin D and PLTs is represented by their role in mineral metabolism and bone health, since vitamin D deficiency, low PLT count, and altered PLT-related parameters are linked to abnormal bone remodeling in certain pathological conditions, such as osteoporosis (OP). Hence, it is possible to speculate that severe COVID-19 patients are characterized by the presence of several predisposing factors to bone fragility and OP that may be monitored to avoid potential complications. Here, we hypothesize different pervasive actions of vitamin D and PLT association in COVID-19, also allowing for potential preliminary information on bone health status during COVID-19 infection.

Low 25(OH)D Level Is Associated with Severe Course and Poor Prognosis in COVID-19.

We evaluated associations between serum 25-hydroxyvitamin D [25(OH)D] level and severity of new coronavirus infection (COVID-19) in hospitalized patients. We assessed serum 25(OH)D level in 133 patients aged 21-93 years. Twenty-five (19%) patients had severe disease, 108 patients (81%) had moderate disease, and 18 (14%) patients died. 25(OH)D level ranged from 3.0 to 97.0 ng/mL (median, 13.5 [25%; 75%, 9.6; 23.3] ng/mL). Vitamin D deficiency was diagnosed in 90 patients, including 37 with severe deficiency. In patients with severe course of disease, 25(OH)D level was lower (median, 9.7 [25%; 75%, 6.0; 14.9] ng/mL), and vitamin D deficiency was more common than in patients with moderate course (median, 14.6 [25%; 75%, 10.6; 24.4] ng/mL, p = 0.003). In patients who died, 25(OH)D was 9.6 [25%; 75%, 6.0; 11.5] ng/mL, compared with 14.8 [25%; 75%, 10.1; 24.3] ng/mL in discharged patients (p = 0.001). Severe vitamin D deficiency was associated with increased risk of COVID-19 severity and fatal outcome. The threshold for 25(OH)D level associated with increased risk of severe course was 11.7 ng/mL. Approximately the same 25(OH)D level, 10.9 ng/mL, was associated with increased risk of mortality. Thus, most COVID-19 patients have vitamin D deficiency; severe vitamin D deficiency is associated with increased risk of COVID-19 severity and fatal outcome.

Vitamin D supplementation prior to or during COVID-19 associated with better 3-month survival in geriatric patients: Extension phase of the GERIA-COVID study.

BACKGROUND: The objective of this extension phase of the quasi-experimental GERIA-COVID study was to determine whether vitamin D3 supplementation taken prior to or during COVID-19 was associated with better 3-month survival in geriatric patients hospitalized for COVID-19. METHODS: Intervention group was defined as all participants supplemented with vitamin D3 prior to or during COVID-19 (n = 67). Supplements were either bolus vitamin D3 (ie, 50,000 IU per month, or 80,000 IU or 100,000 IU or 200,000 IU every 2-3 months), or daily supplementation with 800 IU. Comparator group involved those without vitamin D supplements (n = 28). Outcome was 3-month mortality. Covariables were age, sex, functional abilities, history of malignancies, cardiomyopathy, undernutrition, number of acute health issues, antibiotics use, systemic corticosteroids use, and 25(OH)D concentration. RESULTS: 76.1 % (n = 51) of participants survived at 3 months in Intervention group, compared to only 53.6 % (n = 15) in Comparator group (P = 0.03). The fully-adjusted hazard ratio for 3-month mortality was HR = 0.23 [95 %CI: 0.09;0.58](P = 0.002) in Intervention group compared to Comparator group. Intervention group had also longer survival time (log-rank P = 0.008). CONCLUSIONS: Vitamin D3 supplementation was associated with better 3-month survival in older COVID-19 patients.

Screening for Vitamin D Deficiency in Adults: US Preventive Services Task Force Recommendation Statement.

Importance: Vitamin D is a fat-soluble vitamin that performs an important role in calcium homeostasis and bone metabolism and also affects many other cellular regulatory functions outside the skeletal system. Vitamin D requirements may vary by individual; thus, no one serum vitamin D level cutpoint defines deficiency, and no consensus exists regarding the precise serum levels of vitamin D that represent optimal health or sufficiency. Objective: To update its 2014 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on screening for vitamin D deficiency, including the benefits and harms of screening and early treatment. Population: Community-dwelling, nonpregnant adults who have no signs or symptoms of vitamin D deficiency or conditions for which vitamin D treatment is recommended. Evidence Assessment: The USPSTF concludes that the overall evidence on the benefits of screening for vitamin D deficiency is lacking. Therefore, the balance of benefits and harms of screening for vitamin D deficiency in asymptomatic adults cannot be determined. Recommendation: The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for vitamin D deficiency in asymptomatic adults. (I statement).

Mortality in Hemodialysis Patients with COVID-19, the Effect of Paricalcitol or Calcimimetics.

BACKGROUND: In COVID-19 patients, low serum vitamin D (VD) levels have been associated with severe acute respiratory failure and poor prognosis. In regular hemodialysis (HD) patients, there is VD deficiency and markedly reduced calcitriol levels, which may predispose them to worse outcomes of COVID-19 infection. Some hemodialysis patients receive treatment with drugs for secondary hyperparathyroidism, which have well known pleiotropic effects beyond mineral metabolism. The aim of this study was to evaluate the impact of VD status and the administration of active vitamin D medications, used to treat secondary hyperparathyroidism, on survival in a cohort of COVID-19 positive HD patients. METHODS: A cross-sectional retrospective observational study was conducted from 12 March to 21 May 2020 in 288 HD patients with positive PCR for SARS-CoV2. Patients were from 52 different centers in Spain. RESULTS: The percent of HD patients with COVID-19 was 6.1% (288 out of 4743). Mortality rate was 28.4% (81/285). Three patients were lost to follow-up. Serum 25(OH)D (calcidiol) level was 17.1 [10.6-27.5] ng/mL and was not significantly associated to mortality (OR 0.99 (0.97-1.01), p = 0.4). Patients receiving active vitamin D medications (16/94 (17%) vs. 65/191(34%), p = 0.003), including calcimimetics (4/49 (8.2%) vs. 77/236 (32.6%), p = 0.001), paricalcitol or calcimimetics (19/117 (16.2%) vs. 62/168 (36.9%); p < 0.001), and also those on both paricalcitol and calcimimetics, to treat secondary hyperparathyroidism (SHPTH) (1/26 (3.8%) vs. 80/259 (30.9%), p < 0.001) showed a lower mortality rate than patients receiving no treatment with either drug. Multivariate Cox regression analysis confirmed this increased survival. CONCLUSIONS: Our findings suggest that the use of paricalcitol, calcimimetics or the combination of both, seem to be associated with the improvement of survival in HD patients with COVID-19. No correlation was found between serum VD levels and prognosis or outcomes in HD patients with COVID-19. Prospective studies and clinical trials are needed to support these findings.

Vitamin D Metabolites and Clinical Outcome in Hospitalized COVID-19 Patients.

(1) Background: Vitamin D, a well-established regulator of calcium and phosphate metabolism, also has immune-modulatory functions. An uncontrolled immune response and cytokine storm are tightly linked to fatal courses of COVID-19. The present retrospective study aimed to inves-tigate vitamin D status markers and vitamin D degradation products in a mixed cohort of 148 hospitalized COVID-19 patients with various clinical courses of COVID-19. (2) Methods: The serum concentrations of 25(OH)D3, 25(OH)D2, 24,25(OH)2D3, and 25,26(OH)2D3 were determined by a validated liquid-chromatography tandem mass-spectrometry method in leftover serum samples from 148 COVID-19 patients that were admitted to the University Hospital of the Medical Uni-versity of Graz between April and November 2020. Anthropometric and clinical data, as well as outcomes were obtained from the laboratory and hospital information systems. (3) Results: From the 148 patients, 34 (23%) died within 30 days after admission. The frequency of fatal outcomes did not differ between males and females. Non-survivors were significantly older than survivors, had higher peak concentrations of IL-6 and CRP, and required mechanical ventilation more frequently. The serum concentrations of all vitamin D metabolites and the vitamin D metabolite ratio (VMR) did not differ significantly between survivors and non-survivors. Additionally, the need for res-piratory support was unrelated to the serum concentrations of 25(OH)D vitamin D and the two vitamin D catabolites, as well as the VMR. (4) Conclusion: The present results do not support a relevant role of vitamin D for the course and outcome of COVID-19.

The Impact of COVID-19 Pandemic during 2020-2021 on the Vitamin D Serum Levels in the Paediatric Population in Warsaw, Poland.

BACKGROUND: The main source of vitamin D is skin synthesis, which depends on sunlight exposure. During the pandemic, COVID-19 children were obliged to home confinement, which potentially limiting sunlight exposure. The aim of this study was to evaluate whether home confinement led to decreased vitamin D serum levels in children in Warsaw, Poland. METHODS: The study included 1472 children who were divided into two groups, based on the date of 25(OH)D level blood sampling: before and during the pandemic. Children under 1 year of age (infants) were analysed separately. RESULTS: A statistically significant decrease in the average level of vitamin D was observed between groups of children over 1 year of age (35 ng/mL ± 18 vs. 31 ng/mL ± 14). In infants from both groups, the mean vitamin D levels were within the normal range (Group 1 inf 54 ng/mL ± 21 vs. Group 2 inf 47 ng/mL ± 15). The characteristic seasonal variability was observed before the pandemic, with maximal vitamin D levels in summer (40 ng/mL ± 17) and minimal levels in winter (30 ng/mL ± 14). During the pandemic, no seasonal variability was observed (summer 30 ng/mL ± 11 vs. winter 30 ng/mL ± 19). CONCLUSIONS: The COVID-19 pandemic restrictions led to a significant decrease in vitamin D serum levels in children.

Bad Prognosis in Critical Ill Patients with COVID-19 during Short-Term ICU Stay regarding Vitamin D Levels.

BACKGROUND AND AIMS: Vitamin D inadequacy may be involved in the mechanisms of SARS-CoV-2 infection and in potential risk factors for disease propagation or control of coronavirus disease 2019 (COVID-19). This study assessed a short-term evolution of vitamin D status and its influence upon different clinical parameters in critically ill patients with COVID-19. METHODS: A prospective analytical study in which 37 critically ill volunteers between 41 and 71 years of age with COVID-19 were evaluated at baseline and three days of intensive care unit (ICU) stay. 25-OH-D3 and 25-OH-D2 were analyzed by liquid chromatography-tandem mass spectrometry and total 25-OH-D levels were calculated as the sum of both. RESULTS: All patients presented low 25-OH-D levels at baseline, decreasing total 25-OH-D (p = 0.011) mainly through 25-OH-D2 (p = 0.006) levels during ICU stay. 25-OH-D2 levels decreased a mean of 41.6% ± 89.6% versus 7.0% ± 23.4% for the 25-OH-D3 form during the ICU stay. Patients who did not need invasive mechanical ventilation presented higher levels of 25-OH-D2 at baseline and follow-up. Lower 25-OH-D and 25-OH-D3 levels were associated with higher D-dimer at baseline (p = 0.003; p = 0.001) and at follow up (p = 0.029), higher procalcitonin levels (p = 0.002; p = 0.018) at follow up, and lower percentage lymphocyte counts (p = 0.044; p = 0.040) during ICU stay. CONCLUSIONS: Deficient vitamin D status in critical patients was established at the admission and further worsened after three days of stay. Lower vitamin D levels were related to key altered clinical and biochemical parameters on patients with SARS-CoV-2 infection. Given the different response of the 25-OH-D3 and 25-OH-D2 forms, it would be useful to monitor them on the evolution of the critically ill patient.