The relationship between vitamin D status and idiopathic lower-extremity deep vein thrombosis

Emerging role of vitamin D deficiency as a risk factor for retinal venous occlusions and need for public health measures for its prevention

Purpose

To estimate levels of serum vitamin D in patients of retinal vein occlusion (RVO) and compare with age- and sex-matched controls.

Methods

A prospective case-control study of 54 patients of RVO and 54 age- and sex-matched attendants of patients presenting to a tertiary care hospital in Delhi was performed. Patients on vitamin D supplementations and RVO due to infective or immunological causes or patients of glaucoma were excluded. Serum vitamin D levels of all the study participants along with relevant blood investigations with history and examination were documented. Vitamin D deficiency was defined as <20 ng/ml.

Results

The mean serum vitamin D levels seen in RVO patients and the control group were 14.19 ± 5.23 ng/ml and 19.42 ± 10.27 ng/ml, respectively (P value = 0.001) with an odds ratio of 10.558 (CI = 2.34-47.50), indicating vitamin D deficiency to be strongly correlated with RVO. Maximum patients of RVO (46.3%) were seen during the winter season. The study noted hypertension [odds ratio 20.22 (CI = 5.812-70.347)], dyslipidemia, and anemia [odds ratio 4.107 (CI = 0.62-26.90)] to be the risk factors for RVO as previously proved in the literature. Smoking, diabetes, alcohol intake, and body mass index did not emerge as risk factors for RVO.

Conclusion

Vitamin D deficiency is associated with RVO; hence, estimation of serum vitamin D levels should be advised as a part of routine investigations while looking for the cause of RVOs. Public health measures like food fortification with vitamin D micronutrients and public awareness towards increased sunlight exposure in the community are simple, inexpensive measures that can decrease the burden of sight-threatening disease of RVO in the community.

The Effects of Malnutrition on Inpatient Outcomes in Patients With Gastroparesis: A Nationwide Analysis

Introduction Gastroparesis (GP) is a chronic debilitating gastric motility disorder defined as delayed emptying of the stomach content without mechanical obstruction. It can result in nutritional deficiencies, leading to poor overall outcomes. We assessed the impact of malnutrition on in-hospital outcomes in patients with gastroparesis. Methods Patients with a primary discharge diagnosis of GP between January 2016 and December 2019 were included in the National Inpatient Sample (NIS) database. Data on patient demographics, hospital characteristics, the Charlson Comorbidity Index (CCI), and the etiology of gastroparesis were collected. The association between malnutrition and outcomes, including mortality, deep vein thrombosis (DVT), pulmonary embolism (PE), sepsis, acute kidney injury (AKI), length of stay (LOS), and total hospitalization charges (THC), were analyzed using the multivariate regression model. Results A total of 182,580 patients with gastroparesis were included in the analysis. Patients with gastroparesis and malnutrition had a higher risk of mortality (adjusted odds ratio {aOR}, 3.29; p<0.001), sepsis (aOR, 0.43; p<0.001), DVT (aOR, 2.34; p<0.001), and PE (aOR, 2.68; p<0.001) compared to patients with gastroparesis without malnutrition. No significant difference was noted in the rates of AKI. Patients with malnutrition also had a prolonged LOS (2.96 days; p<0.001) and higher THC ($22,890; p<0.001) compared to patients without malnutrition. Conclusion Gastroparesis patients with malnutrition are at a greater risk of worse outcomes than those without malnutrition. The early identification of malnutrition in gastroparesis patients can predict morbidity and mortality and assist in risk stratification to enhance outcomes. Further studies are encouraged to identify factors associated with malnutrition in gastroparesis and the impact of interventions to prevent and treat malnutrition.

Prevalence and Impact of Malnutrition in Hospitalizations Among Celiac Diseases: A Nationwide Analysis

BACKGROUND/AIMS

Celiac disease (CD) is a T-cell-mediated gluten sensitivity that results in villous atrophy in the small intestine, leading to chronic malabsorption. Patients with celiac disease are prone to malnutrition. We assessed the impact of malnutrition on in-hospital outcomes in patients with CD.

MATERIALS AND METHODS

Patients with a primary discharge diagnosis of CD between January 2016 and December 2019 were included in the National Inpatient Sample Database. Data were collected on patient demographics, hospital characteristics, the Charlson Comorbidity Index (CCI), and concomitant comorbidities. The association between malnutrition and outcomes, including mortality, deep vein thrombosis (DVT), pulmonary embolism (PE), sepsis, acute kidney injury (AKI), length of stay (LOS), and total hospitalization charges (THC), was analyzed using the multivariate regression model.

RESULTS

A total of 187310 patients with CD were included in the analysis. Patients with CD and malnutrition had a higher risk of mortality (adjusted odds ratio [aOR], 2.08; p<0.001), AKI (aOR=1.18, p=0.003), and DVT (aOR=1.53; p<0.001) compared to patients with CD without malnutrition. No significant difference was noted in the rates of sepsis and PE. Patients with malnutrition also had a prolonged LOS (2.89 days; p<0.001) and higher THC ($22252.18; p<0.001) compared to patients without malnutrition.

DISCUSSION

Patients with CD and malnutrition are at high risk of worse outcomes. Early identification of malnutrition in CD can help prevent morbidity and mortality. Even strict adherence to a gluten-free diet has been associated with malnutrition. Further studies identifying factors associated with malnutrition in CD and the impact of interventions to prevent and treat malnutrition are encouraged.

Is Circulating Vitamin D Status Associated with the Risk of Venous Thromboembolism? A Meta-Analysis of Observational Studies

BACKGROUND

Although vitamin D is antithrombotic, associations between serum vitamin D status and the risk of venous thromboembolism (VTE) remain inconsistent.

METHODS

We searched the EMBASE, MEDLINE, Cochrane Library, and Google Scholar databases from inception to June 2022 to identify observational studies examining associations between vitamin D status and VTE risk in adults. The primary outcome presented as odds ratio (OR) or hazard ratio (HR) was the association of vitamin D levels with the risk of VTE. Secondary outcomes included the impacts of vitamin D status (i.e., deficiency or insufficiency), study design, and the presence of neurological diseases on the associations.

RESULTS

Pooled evidence from a meta-analysis of sixteen observational studies, including 47648 individuals published from 2013 to 2021, revealed a negative relationship between vitamin D levels and the risk of VTE either based on OR (1.74, 95% confidence interval (CI): 1.37 to 2.20, p < 0.00001; I² = 31%, 14 studies, 16074 individuals) or HR (1.25, 95% CI: 1.07 to 1.46, p = 0.006; I² = 0%, 3 studies, 37,564 individuals). This association remained significant in subgroup analyses of the study design and in the presence of neurological diseases. Compared to individuals with normal vitamin D status, an increased risk of VTE was noted in those with vitamin D deficiency (OR = 2.03, 95% CI: 1.33 to 3.11) but not with vitamin D insufficiency.

CONCLUSIONS

This meta-analysis demonstrated a negative association between serum vitamin D status and the risk of VTE. Further studies are required to investigate the potential beneficial effect of vitamin D supplementation on the long-term risk of VTE.

Vitamin D Endocrine System and COVID-19: Treatment with Calcifediol

The COVID-19 pandemic is the greatest challenge facing modern medicine and public health systems. The viral evolution of SARS-CoV-2, with the emergence of new variants with in-creased infectious potential, is a cause for concern. In addition, vaccination coverage remains in-sufficient worldwide. Therefore, there is a need to develop new therapeutic options, and/or to optimize the repositioning of drugs approved for other indications for COVID-19. This may include the use of calcifediol, the prohormone of the vitamin D endocrine system (VDES) as it may have potential useful effects for the treatment of COVID-19. We review the aspects associating COVID-19 with VDES and the potential use of calcifediol in COVID-19. VDES/VDR stimulation may enhance innate antiviral effector mechanisms, facilitating the induction of antimicrobial peptides/autophagy, with a critical modulatory role in the subsequent host reactive hyperinflammatory phase during COVID-19: By decreasing the cytokine/chemokine storm, regulating the renin–angiotensin–bradykinin system (RAAS), modulating neutrophil activity and maintaining the integrity of the pulmonary epithelial barrier, stimulating epithelial repair, and directly and indirectly decreasing the increased coagulability and prothrombotic tendency associated with severe COVID-19 and its complications. Available evidence suggests that VDES/VDR stimulation, while maintaining optimal serum 25OHD status, in patients with SARS-CoV-2 infection may significantly reduce the risk of acute respiratory distress syndrome (ARDS) and severe COVID-19, with possible beneficial effects on the need for mechanical ventilation and/or intensive care unit (ICU) admission, as well as deaths in the course of the disease. The pharmacokinetic and functional characteristics of calcifediol give it superiority in rapidly optimizing 25OHD levels in COVID-19. A pilot study and several observational intervention studies using high doses of calcifediol (0.532 mg on day 1 and 0.266 mg on days 3, 7, 14, 21, and 28) dramatically decreased the need for ICU admission and the mortality rate. We, therefore, propose to use calcifediol at the doses described for the rapid correction of 25OHD deficiency in all patients in the early stages of COVID-19, in association, if necessary, with the new oral antiviral agents.

Vitamin D, infections and immunity

Vitamin D, best known for its role in skeletal health, has emerged as a key regulator of innate immune responses to microbial threat. In immune cells such as macrophages, expression of CYP27B1, the 25-hydroxyvitamin D 1α-hydroxylase, is induced by immune-specific inputs, leading to local production of hormonal 1,25-dihydroxyvitamin D (1,25D) at sites of infection, which in turn directly induces the expression of genes encoding antimicrobial peptides. Vitamin D signaling is active upstream and downstream of pattern recognition receptors, which promote front-line innate immune responses. Moreover, 1,25D stimulates autophagy, which has emerged as a mechanism critical for control of intracellular pathogens such as M. tuberculosis. Strong laboratory and epidemiological evidence links vitamin D deficiency to increased rates of conditions such as dental caries, as well as inflammatory bowel diseases arising from dysregulation of innate immune handling intestinal flora. 1,25D is also active in signaling cascades that promote antiviral innate immunity; 1,25D-induced expression of the antimicrobial peptide CAMP/LL37, originally characterized for its antibacterial properties, is a key component of antiviral responses. Poor vitamin D status is associated with greater susceptibility to viral infections, including those of the respiratory tract. Although the severity of the COVID-19 pandemic has been alleviated in some areas by the arrival of vaccines, it remains important to identify therapeutic interventions that reduce disease severity and mortality, and accelerate recovery. This review outlines of our current knowledge of the mechanisms of action of vitamin D signaling in the innate immune system. It also provides an assessment of the therapeutic potential of vitamin D supplementation in infectious diseases, including an up-to-date analysis of the putative benefits of vitamin D supplementation in the ongoing COVID-19 crisis.

The role of vitamin D in cardiovascular disease and COVID-19

Patients with pre-existing cardiovascular disease (CVD) are at high risk for adverse outcomes with coronavirus disease 2019 (COVID-19). Further, COVID-19 infection is associated with numerous cardiovascular (CV) complications including arrhythmia, myocardial injury, cardiomyopathy, and thrombotic events. Increased susceptibility to COVID-19 and CV complications related to COVID-19 may be in part related to immune dysregulation and inflammation associated with CV disease which is exacerbated with viral infection. Vitamin D plays a major role in immune function and exerts anti-inflammatory effects, which may prove important in the context of CVD and COVID-19. To date, studies have shown minimal benefit for vitamin D supplementation in patients with COVID-19, though there are no studies specific to patients with CVD and related complications. Further, given that vitamin D has important protective effects on the CV system, including augmentation of myocardial contractility and anti-thrombotic effects, it is unknown if supplementation with vitamin D can mitigate CVD complications associated with COVID-19.

Retrospective analysis of vitamin D status on ınflammatory markers and course of the disease in patients with COVID-19 infection

PURPOSE

The aim of the study was to investigate the association between serum 25-hydroxyvitamin D status within the last 6 months prior to COVID-19 infection and parameters of immune function and clinical outcomes.

METHODS

Fifty-six patients, who were admitted to the emergency clinic and diagnosed with COVID-19 infection, were included in the study. Data on clinical characteristics, inflammatory parameters and vitamin D status were recorded for each patient. All the participants had data on 25-hydroxyvitamin D status within the last 6 months prior to COVID-19 infection.

RESULTS

The patients were stratified as those with vitamin D status less than 20 ng/mL and higher than 20 ng/mL. A group with vitamin D status less than 20 ng/mL had lower lymphocyte counts and lower haemoglobin levels that was statistically significant (respectively; p = 0.021, p = 0.035). Higher C-reactive protein (CRP) levels were seen in the vitamin D-deficient group (p = 0.013). It was observed that vitamin D status of the patients who required oxygen therapy were lower than those who did not require oxygen therapy, not statistically significant (p = 0.05). Patients who did not use vitamin D supplementation within 6 months prior to COVID-19 infection had more likely to be diagnosed with pneumonia (p = 0.004).

CONCLUSION

Cases with lower vitamin D status had increased inflammatory markers and worse clinical outcomes than patients with higher vitamin D status. This study suggests that vitamin D status can be used as a prognostic factor in COVID-19 patients, and vitamin D supplementation can be recommended to improve the clinical outcomes in COVID-19 infection.

Vitamin D Endocrine System and COVID-19

Preclinical data strongly suggest that the vitamin D endocrine system (VDES) may have extraskeletal effects. Cells of the immune and cardiovascular systems and lungs can express the vitamin D receptor, and overall these cells respond in a coherent fashion when exposed to 1,25-dihydroxyvitamin D, the main metabolite of the VDES. Supplementation of vitamin D-deficient subjects may decrease the risk of upper respiratory infections. The VDES also has broad anti-inflammatory and anti-thrombotic effects, and other mechanisms argue for a potential beneficial effect of a good vitamin D status on acute respiratory distress syndrome, a major complication of this SARS-2/COVID-19 infection. Activation of the VDES may thus have beneficial effects on the severity of COVID-19. Meta-analysis of observational data show that a better vitamin D status decreased the requirement of intensive care treatment or decreased mortality. A pilot study in Cordoba indicated that admission to intensive care was drastically reduced by administration of a high dose of calcifediol early after hospital admission for COVID-19. A large observational study in Barcelona confirmed that such therapy significantly decreased the odds ratio (OR) of mortality (OR = 0.52). This was also the conclusion of a retrospective study in five hospitals of Southern Spain. A retrospective study on all Andalusian patients hospitalized because of COVID-19, based on real-world data from the health care system, concluded that prescription of calcifediol (hazard ratio [HR] = 0.67) or vitamin D (HR = 0.75), 15 days before hospital admission decreased mortality within the first month. In conclusion, a good vitamin D status may have beneficial effects on the course of COVID-19. This needs to be confirmed by large, randomized trials, but in the meantime, we recommend (rapid) correction of 25 hydroxyvitamin D (25OHD) deficiency in subjects exposed to this coronavirus. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Rays of immunity: Role of sunshine vitamin in management of COVID-19 infection and associated comorbidities

The catastrophic pandemic engendered due to the Novel coronavirus (COVID-19) outbreak which causes severe clinical afflictions on the respiratory system has severely high morbidity and mortality rates. The requirement of novel compounds is at utmost importance due to lack of targeted drug molecule to treat the afflictions and restrict the viral infection and for the usage of prophylactic treatment to avoid the spread of the infection is of utmost importance. Vitamin D is one such naturally available multifunctional molecule, which plays an eminent role in the immune system and instigation of numerous cellular pathways further promoting health benefits and enhancing the human quality of life. This article reviews the current standpoint scenario and future prevalence of vitamin D supplementation in the management of covid-19 patients. Novel findings of Vitamin D suggest that along with regulation of cell growth, neuroprotective and mood-stabilizing effects, it regulates the immune response also modulate cytokine Interleukin-6 (IL-6) by inducing progesterone-induced blocking factor (PIBF), given the IL-6 levels are considerably high in COVID-19 patients which increases the further complications. Vitamin D also have its effect on angiotensin converting enzyme (ACEII) inhibitor through which the COVID-19 virus makes cell entry. Numerous research data elucidate the play of Vitamin D, in complications of COVID-19 including the most common comorbid conditions, neurological manifestations and immunological aspects makes it an ideal molecule for adjuvant therapy. Including Vitamin D as add-on therapy in the management of COVID-19 might aid the arrest of infection and helps fight this arduous epidemic.

Low levels of vitamin D were associated with coagulopathy among hospitalized coronavirus disease-19 (COVID-19) patients: A single-centered study in Indonesia

Background

This study was aimed to explore the association of vitamin D in the risk of coagulopathy in coronavirus disease-19 (COVID-19).

Methods

Clinical and laboratory findings were obtained from 50 confirmed COVID-19 patients hospitalized in Saiful Anwar General Hospital, Malang, Indonesia, from September to November 2020. Thrombotic events during hospitalization were recorded, and the ISTH disseminated intravascular coagulation (DIC) score was used to classify overt DIC. Hypovitaminosis D was defined by serum vitamin D level <49.92 nmol/L.

Results

Among 50 patients, 42 (84%) had hypovitaminosis D, and 6 (12%) developed thrombotic events. Vitamin D levels were lower in patients with thrombotic events (p=0.015), D-dimer >2 mg/L (p=0.006), ISTH DIC score 5 (p=0.020), admitted on ICU (p=0.002), and non-survivor groups (p=0.007). Multivariate analysis for the risk in increased D-dimer levels showed low vitamin D as the only significant risk factor with OR 1.8 (1.2-4.4), p=0.034. Low vitamin D also increased the risk for developing overt DIC with OR. 5.4 (1.0-30.2), p=0.039. Vitamin D level had negative correlations with ferritin (R=-0.316, p=0.044) and CRP (R=-0.530, p=0.000).

Conclusions

In conclusion, a low level of vitamin D was found in most hospitalized COVID-19 patients and might be associated with the development of coagulopathy.

Relevance of vitamin D3 in COVID-19 infection

SARS-CoV-2 virus, the main culprit for COVID-19 disaster, has triggered a gust of curiosity both in the mechanism of action of this infection as well as potential risk factors for disease generation and regimentation. The prime focus of the present review, which is basically a narrative one, is in utilizing the current concepts of vitamin D3 as an agent with myriad functions, one of them being immunocompetence and a promising weapon for both innate and adaptive immunity against COVID-19 infection. Some of the manifestations of SARS-CoV-2 virus such as Acute Respiratory Distress Syndrome (ARDS) overlap with the pathophysiological effects that are overcome due to already established role of vitamin D3 e.g., amelioration of cytokine outburst. Additionally, the cardiovascular complications due to COVID-19 infection may also be connected to vitamin D3 levels and the activity of its active forms. Eventually, we summarise the clinical, observational and epidemiological data of the respiratory diseases including COVID-19 disease and try to bring its association with the potential role of vitamin D3, in particular, the activity of its active forms, circulating levels and its supplementation, against dissemination of this disease.

Low Vitamin D Level Is Associated with Acute Deep Venous Thrombosis in Patients with Traumatic Brain Injury

Vitamin D and its association with venous thromboembolism (VTE) have been studied in common rehabilitation populations, such as spinal cord injury and ischemic stroke groups. This study explores the relationship between vitamin D levels and acute deep venous thrombosis (DVT) in the traumatic brain injury (TBI) population. This is a retrospective cohort study that analyzes the relationship between vitamin D levels and the prevalence of DVT during acute inpatient rehabilitation. In this population, 62% (117/190) of patients had low vitamin D levels upon admission to acute rehabilitation. Furthermore, 21% (24/117) of patients in the low vitamin D group had acute DVT during admission to acute rehabilitation. In contrast, only 8% (6/73) of patients in the normal vitamin D group had acute DVT during admission to acute rehabilitation. Fisher’s exact tests revealed significant differences between individuals with low and normal vitamin D levels (p = 0.025). In conclusion, a vitamin D level below 30 ng/mL was associated with increased probability of the occurrence of acute DVT in individuals with moderate–severe TBI.

Vitamin D status and complications, readmissions, and mortality after hip fracture

Low vitamin D in patients with hip fracture is common. In the present study, 407 of 872 (47%) patients had serum calcidiol less than 50 nmol/L. Patients with low vitamin D had more delirium, more new hip fractures, and more medical readmissions, but not more orthopedic complications after 1 year.

INTRODUCTION

We wanted to study the relation between vitamin D level and postoperative orthopedic and medical complications in patients with hip fracture. In addition, we investigated the effect of giving a single-dose cholecalciferol 100.000 IU.

METHODS

Data were taken from the local hip fracture register. Logistic regression analyses including vitamin D level and potentially confounding variables were performed for complications and readmissions.

RESULTS

A total of 407 (47%) of 872 included hip fractures had low vitamin D at baseline. A total of 155 (18%) developed delirium, and the risk was higher in vitamin D-deficient patients (odds ratio (OR) 1.48, 95% confidence interval (CI) 1.04 to 2.12; p = 0.03). A total of 261 (30%) were readmitted for non-hip-related conditions. Low vitamin D was associated with a higher risk of medical readmissions within 30 days (OR 1.64 (1.03 to 2.61); p = 0.036) and 12 weeks (OR 1.47 (95% CI 1.02 to 2.12); p = 0.039). There was a higher risk of a new hip fracture (OR 2.84 (95% CI 1.15 to 7.03) p = 0.024) in vitamin D-deficient patients. A total of 105 (12%) developed at least one orthopedic complication, with no correlation to baseline vitamin D. Among vitamin D-deficient patients, those receiving a single-dose of 100.000 IU cholecalciferol had fewer orthopedic complications (OR 0.32 (95% CI 0.11 to 0.97) p = 0.044) the first 30 days after surgery.

CONCLUSION

Low vitamin D at admission for hip fracture increased the risk of delirium, a new hip fracture, and medical readmissions, but not orthopedic complications. The role of vitamin D supplementation to prevent orthopedic complications requires further study.

Role of vitamin D in treating COVID-19-associated coagulopathy: problems and perspectives

Aggressive inflammatory response leading to hypercoagulability has been found to be associated with disease severity in COVID-19 patients and portends bad treatment outcome. A state of acute disseminated intravascular coagulation (DIC), along with pulmonary embolism and/or deep vein thrombosis, has been observed in critically ill ICU patients. Autopsy reports of COVID-19 patients demonstrated microthrombi in lungs and in other organs, as well as marked inflammatory changes, characteristic clinicopathological features that exacerbate disease severity. Vitamin D supplementation was recommended by many clinicians across the globe to improve clinical symptoms of COVID-19 patients, mainly because of its immunomodulatory roles on immune cells. Furthermore, vitamin D and its associated molecules are also known to directly or indirectly regulate various thrombotic pathways. We propose that vitamin D supplementation not only attenuates the risk of Acute Respiratory Disease Syndrome (ARDS) but it also may have a role in reducing coagulation abnormalities in critically ill COVID-19 patients. The overarching goal of this review is to discuss the effects of vitamin D on coagulation pathways and other intertwined processes leading to thrombosis. Many clinical trials are currently investigating the efficacy of vitamin D supplementation in reducing the risk of COVID-19 infection. However, randomized placebo control clinical trials are also necessary to ascertain the effect of vitamin D supplementation on reducing the risk of coagulopathy in COVID-19 patients.

MECHANISMS IN ENDOCRINOLOGY: Vitamin D and COVID-19

The SARS-CoV-2 virus responsible for the COVID-19 pandemic has generated an explosion of interest both in the mechanisms of infection leading to dissemination and expression of this disease, and in potential risk factors that may have a mechanistic basis for disease propagation or control. Vitamin D has emerged as a factor that may be involved in these two areas. The focus of this article is to apply our current understanding of vitamin D as a facilitator of immunocompetence both with regard to innate and adaptive immunity and to consider how this may relate to COVID-19 disease. There are also intriguing potential links to vitamin D as a factor in the cytokine storm that portends some of the most serious consequences of SARS-CoV-2 infection, such as the acute respiratory distress syndrome. Moreover, cardiac and coagulopathic features of COVID-19 disease deserve attention as they may also be related to vitamin D. Finally, we review the current clinical data associating vitamin D with SARS-CoV-2 infection, a putative clinical link that at this time must still be considered hypothetical.

Emerging Role of Vitamin D and its Associated Molecules in Pathways Related to Pathogenesis of Thrombosis

Vitamin D, besides having an essential role in calcium and bone metabolism, also acts as a mediator of many non-calcemic effects through modulations of several biological responses. Vitamin D exists in its two major forms, vitamin D₂, or commonly known as ergocalciferol, and vitamin D₃, or commonly known as cholecalciferol. Both of these forms bind to vitamin D-binding protein to get transported to all vital target organs, where it serves as a natural ligand to vitamin D receptors for enabling their biological actions. Clinical reports corroborating vitamin D deficiency with an increase in thrombotic episodes implicate the role of vitamin D and its associated molecule in the regulation of thrombosis-related pathways. Thrombosis is the formation and propagation of a blood clot, known as thrombus. It can occur either in the arterial or the venous system resulting in many severe complications, including myocardial infarction, stroke, ischemia, and venous thromboembolism. Vitamin D, directly or indirectly, controls the expression of several genes responsible for the regulation of cellular proliferation, differentiation, apoptosis, and angiogenesis. All of these are the processes of potential relevance to thrombotic disorders. This review, thus, discussed the effects of vitamin D on pathways involved in thrombosis, such as hemostatic process, inflammatory pathway, and endothelial cell activation, with a focus on the molecular mechanisms associated with them.

Low Vitamin D Levels Are Associated With the Development of Deep Venous Thromboembolic Events in Patients With Ischemic Stroke

The objective is to determine whether a low serum 25-hydroxyvitamin D (25(OH)D) level is associated with an increased incidence of deep venous thromboembolic events in patients with ischemic stroke. One hundred eighty persons admitted consecutively for inpatient rehabilitation at the Department of Rehabilitation of the First Affiliated Hospital of Wenzhou Medical University with a diagnosis of ischemic stroke from January 2015 to December 2015 were enrolled. The following demographic data were collected: age, sex, body mass index, and history of risk factors. The levels of 25(OH)D and the presence of deep vein thrombosis (DVT) by routine duplex imaging were also recorded. The value of 25(OH)D needed to predict DVT was analyzed using logistic regression analysis, after adjusting for the possible confounders. We found that 80% of patients admitted to the acute inpatient rehabilitation unit had low levels of vitamin D. Forty-seven patients had DVT, and the incidence of DVT was 26.1% within 3 weeks after the stroke event. With all patients taken together, DVT occurrence as a dependent variable with the sufficient group as the reference used for vitamin D levels in the logistic analysis, deficiency of vitamin D was independently associated with the development of DVT (odds ratio = 4.683, 95% confidence interval: 1.396-15.703, P = .012). In conclusion, low serum 25(OH)D levels were independent predictors of DVT in patients with ischemic stroke during inpatient rehabilitation stay in China. This finding reveals the critical role played by 25(OH)D in the pathogenesis of DVT.

Coagulation factor V gene 1691G>A polymorphism as an indicator for risk and prognosis of lower extremity deep venous thrombosis in Chinese Han population

The purpose of this study was to explore the negative influence coagulation factor V (FV) 1691G>A polymorphism had on the risk and prognosis of lower extremity deep venous thrombosis (LDVT) in Chinese Han population.A total of 348 patients with LDVT (LDVT group) and 398 healthy individuals (control group) were selected to further this study. A polymerase chain reaction-restriction fragment length polymorphism method was used to analyze the FV gene 1691G>A polymorphism; coagulation and anticoagulation indexes of patients with LDVT were detected as a result. A 3-year follow-up and logistic regression analysis were conducted to determine the corresponding correlations between FV gene and LDVT.In comparison with the control group, the frequencies of GA and AA genotypes and A allele of 1691G>A polymorphism significantly increased in the LDVT group. Also, in comparison with patients with LDVT carrying GG genotype of FV gene 1691G>A polymorphism, the following activities reduced significantly: prothrombin time, activated partial thromboplastin time, fibrinogen, protein C, and protein S, while activated protein C resistance and lupus anticoagulant positive rate increased in patients carrying A allele (GA + AA). Logistic regression analysis indicated that FV gene 1691G>A polymorphism, total cholesterol, low-density lipoprotein cholesterol, and LDVT family histories were all closely related with LDVT and were subsequent independent risk factors for LDVT. Moreover, patients with LDVT carrying A allele (GA + AA) had both higher patency and recurrence rates than those carrying GG genotype.FV gene 1691G>A polymorphism may be associated with both the risk and prognosis of LDVT, potentially being a useful index for monitoring LDVT prognosis and risk.

The Role of Toll-Like Receptors and Vitamin D in Cardiovascular Diseases-A Review

Cardiovascular diseases are the leading cause of mortality worldwide. Therefore, a better understanding of their pathomechanisms and the subsequent implementation of optimal prophylactic and therapeutic strategies are of utmost importance. A growing body of evidence states that low-grade inflammation is a common feature for most of the cardiovascular diseases in which the contributing factors are the activation of toll-like receptors (TLRs) and vitamin D deficiency. In this article, available data concerning the association of cardiovascular diseases with TLRs and vitamin D status are reviewed, followed by a discussion of new possible approaches to cardiovascular disease management.

Decreased Serum 25-hydroxyvitamin D Level Causes Interventricular Septal Hypertrophy in Patients on Peritoneal Dialysis: Cardiovascular Aspects of Endogenous Vitamin D Deficiency

Introduction. In the present study, we aimed to analyze the relation of vitamin D with echocardiographic indexes in patients with end stage renal disease (ESRD) receiving renal replacement therapy (RRT). Methods. A total of 98 patients, 64 patients on hemodialysis (HD) (29F/35M, mean age 56.75 ± 18.63 years) and 34 age matched patients on peritoneal dialysis (PD) (21F/13M, mean age 58.11 ± 10.63 years), with similar duration of ESRD and RRT were enrolled into this cross-sectional study. Echocardiographic examination was performed after dialysis session at normovolemic status. Fasting blood samples were obtained before dialysis session. Results. Patients on PD and female patients in both groups had significantly lower level of 25-OH-D3 level when compared to patients on HD or male patients (p: 0.0001 and p: 0.0001). When all participants were considered, there was no significant association between 25-OH-D3 and echocardiographic parameters; however, in patients on PD, a significant negative correlation was determined between 25-OH-D3 and diastolic blood pressure, interventricular septal hypertrophy (ISH), and left ventricular mass index (LVMI) (r: −0.424, p: 0.012; r: −0.508, p: 0.004; r: 0.489, p: 0.04, resp.). Conclusion. Low serum 25-hydroxyvitamin D levels is associated with ISH and LVMI in PD patients.