Vitamin D status and the risk of cardiovascular disease death

Association of 25-hydroxyvitamin D, lipoprotein-associated phospholipase A2 and asymptomatic coronary artery disease in patients with type 2 diabetes mellitus

AIM

To evaluate the relationship of 25-hydroxyvitamin D (25(OH)D), lipoprotein-associated phospholipase A2 (Lp-PLA2), and coronary artery disease (CAD) in type 2 diabetes mellitus (T2DM) patients with no history or symptoms of cardiovascular disease.

METHODS

The study identified 66 pairs of T2DM patients with and without CAD using propensity score matching. All subjects performed coronary computed tomography angiography (CCTA). Data on 25(OH)D, Lp-PLA2, and metabolic indexes were collected and analyzed.

RESULTS

Compared to the patients without CAD, the patients with CAD had lower 25(OH)D levels and the rate of vitamin D sufficiency, but higher Lp-PLA2 levels. Meanwhile, subjects in the vitamin D sufficiency group had a lower prevalence of CAD and Lp-PLA2 levels. Furthermore, 25(OH)D was inversely correlated with Lp-PLA2, Gensini score, Leiden score, segment involvement score, and segment stenosis score (P < 0.05). After adjusting for age, gender, blood lipids and blood pressure, 25(OH)D was associated with a decreased risk of CAD (aOR 0.933, 95 %CI 0.887-0.983, P = 0.009), while Lp-PLA2 was associated with an increased risk of CAD (aOR 1.014, 95 %CI 1.005-1.022, P = 0.002).

CONCLUSIONS

Decreased 25(OH)D and increased Lp-PLA2 could identify patients with a high risk of CAD and are associated with the severity of coronary artery stenosis in T2DM.

Cardiovascular and Cerebrovascular Outcomes With Vitamin D Supplementation: A Systematic Review and Meta-Analysis

Vitamin D supplementation has seen a sharp increase in the primary healthcare setting but its efficacy in decreasing the risk of cardiovascular and cerebrovascular events is yet to be reliably established. We aim to determine whether vitamin D supplementation can significantly impact the risk of cardiovascular and cerebrovascular events. An extensive literature search of PubMed, Embase, and Cochrane CENTRAL was conducted from inception till August 2023 to include all the articles comparing vitamin D and placebo. Cardiovascular and cerebrovascular outcomes were presented as risk ratios (RR) with 95% confidence intervals (CIs) and pooled using a random effects model. Thirty-six trials consisting of 493,389 participants were included in our analysis. Our pooled analysis demonstrated no significant difference between vitamin D supplementation and placebo for the risk of cardiovascular mortality (RR 1.01, 95% CI 0.94-1.08; P = 0.80), stroke or cerebrovascular events (RR 1.03, 95% CI 0.95-1.11; P = 0.48), myocardial infarction (MI) (RR 0.98, 95% CI 0.91-1.06; P = 0.65), cerebrovascular mortality (RR 1.00, 95% CI 0.68-1.46; P = 0.99), arrhythmias (RR 0.98, 95% CI 0.66-1.44; P = 0.90) and hemorrhagic or ischemic stroke. There was no significant heterogeneity between the studies in any analysis. There was no significant difference in the risk of cardiovascular and cerebrovascular outcomes with vitamin D supplementation or placebo. Additional large high-powered studies focused on high-risk and vitamin D-deficient populations are required to resolve the current discrepancy in the literature and provide a definitive conclusion to this end.

Vitamin D Supplementation and Cardiovascular Disease Risks in More Than 134000 Individuals in 29 Randomized Clinical Trials and 157000 Individuals in 30 Prospective Cohort Studies: An Updated Systematic Review and Meta-analysis

BACKGROUND

According to the findings from observational studies and clinical trials assessing the effect of vitamin D supplements on cardiovascular diseases (CVDs), there are still contradictory results. This systematic review aimed to assess the effect of vitamin D supplements on CVDs considering cohort studies and clinical trials. Study Design: A systematic review.

METHODS

MEDLINE/PubMed, Science Direct, Embase, and Cochrane Library databases were reviewed by two reviewers independently until 2022. The study effect is risk ratio (RR) and 95% confidence interval (CI) according to Mantel Haenszel's random-effects model. Then, Stata version 14 was used for statistical analysis.

RESULTS

In clinical trial studies, the incidence of CVDs among the vitamin D-consuming group was not significantly different from that in the placebo group (RR: 0.99, 95% CI: 0.95-1.03; P=0.77; I 2=0%). CVD mortality was also not significantly different between the two groups (RR: 0.97, 95% CI: 0.90-1.05; P=0.72; I2=0%). In cohort studies, circulating 25 (OH) D increased the risk of CVD incidence by 31% (RR: 1.31, 95% CI: 1.19-1.45) and CVD mortality by 37% (RR: 1.37, 95% CI: 1.17-1.61).

CONCLUSION

According to current evidence from clinical trials, vitamin D supplementation should not be recommended for CVD prevention. However, there is a direct association between vitamin D deficiency and the incidence of CVDs as well as its mortality. According to the results of clinical trial studies carrying higher levels of scientific evidence, it can be concluded that vitamin D supplementation does not exert a significant effect on the incidence, mortality, and reduction of CVDs.

Association of Genotypes of ANGPTL3 with Vitamin D and Calcium Concentration in Cardiovascular Disease

One of the leading causes of mortality worldwide is cardiovascular disease, which is influenced by some variables, including calcium and vitamin D. This study aimed to assess the relationship between Angiopoietin-Like 3 (ANGPTL3) gene polymorphisms with vitamin D and calcium levels in cardiovascular disease (CVD) patients. In this research, 1002 people participated. Participants' anthropometric parameters, and FBG, calcium, and vitamin D were assessed. Blood samples were used to extract DNA. Taqman®-based polymerase chain reaction (PCR) was used to conduct genetic analysis for the rs10789117 and rs17458195. Statistical analysis was applied to determine differences across subgroups and the relationship between polymorphisms and disease. Age, body mass index (BMI), fasting Blood Sugar (FBG), phenylalanine ammonia-lyase (PAL), and smoking history were significantly correlated with CVD. Vitamin D was statistically associated with rs10789117 and rs17458195 in non-CVD individuals. In the moderate group, individuals with the C allele in rs10789117 showed a tenfold increase in vitamin D deficiency compared to those with the A allele. However, in rs11207997, individuals with the T allele had 5 to 6 times higher vitamin D deficiency than those with the C allele in all groups. This research demonstrates the relationship between some ANGPTL3 gene polymorphisms and complement levels in CVD patients. It may be concluded that individuals carrying these variants would likely benefit from using vitamin D and calcium supplements to avoid CVD.

Non-Conventional Risk Factors: "Fact" or "Fake" in Cardiovascular Disease Prevention?

Cardiovascular diseases (CVDs), such as arterial hypertension, myocardial infarction, stroke, heart failure, atrial fibrillation, etc., still represent the main cause of morbidity and mortality worldwide. They significantly modify the patients' quality of life with a tremendous economic impact. It is well established that cardiovascular risk factors increase the probability of fatal and non-fatal cardiac events. These risk factors are classified into modifiable (smoking, arterial hypertension, hypercholesterolemia, low HDL cholesterol, diabetes, excessive alcohol consumption, high-fat and high-calorie diet, reduced physical activity) and non-modifiable (sex, age, family history, of previous cardiovascular disease). Hence, CVD prevention is based on early identification and management of modifiable risk factors whose impact on the CV outcome is now performed by the use of CV risk assessment models, such as the Framingham Risk Score, Pooled Cohort Equations, or the SCORE2. However, in recent years, emerging, non-traditional factors (metabolic and non-metabolic) seem to significantly affect this assessment. In this article, we aim at defining these emerging factors and describe the potential mechanisms by which they might contribute to the development of CVD.

Sleep patterns modify the association of 25(OH)D with poor cardiovascular health in pregnant women

BACKGROUND

The relationship between vitamin D status and gestational cardiovascular health (CVH) is inconsistent in previous studies. Emerging evidence shows that sleep behaviors are related to vitamin D metabolism. However, no studies evaluate the interaction of vitamin D and sleep behaviors on gestational CVH.

OBJECTIVE

We aimed to estimate the relationship between 25-hydroxyvitamin D [25(OH)D] concentrations and gestational CVH, and whether the relationship was modified by sleep behaviors.

METHODS

The data of this study was from a multicenter birth cohort study. A total of 9,209 pregnant women at 16-23 weeks of gestation were included. 25(OH)D concentrations were measured from collected blood. Sleep patterns consisted of major sleep behaviors including duration, chronotype, insomnia, snoring, and excessive daytime sleepiness. Data on poor CVH was based on four "clinical" CVH metrics, including body mass index, blood pressure, total cholesterol, and glucose levels.

RESULTS

The proportion of women with poor CVH was 25.0%. The relative risk (RR) (95%CI) of poor CVH was 0.67 (0.58-0.76) in women with 25(OH)D ≥ 50 nmol/L after multivariate adjustments. Lower 25(OH)D concentrations were significantly associated with poor CVH. Such association was also evident in subgroups analysis. We found a significant interaction of 25(OH)D (P for interaction = 0.01) with sleep patterns on the risk of poor CVH. A negative dose-response relation was observed between 25(OH)D concentrations and poor CVH risk in healthy or intermediate sleep, not poor sleep. 25(OH)D concentrations were lower and the risk of poor CVH was higher in pregnant women with poor sleep patterns (P < 0.05).

CONCLUSION

Our study suggests that sleep patterns modify the association of 25(OH)D concentrations with the CVH among pregnant women.

The Role of Vitamin D in Stroke Prevention and the Effects of Its Supplementation for Post-Stroke Rehabilitation: A Narrative Review

Hypovitaminosis D is a serious public health problem, representing an independent factor in mortality among the general population. Vitamin D deficiency may affect up to one billion people worldwide. Recently, the potential association between vitamin D levels and stroke has gained increasing attention. Many studies suggest that maintaining normal serum vitamin D levels is associated with improvement of the cardiovascular system and a reduction in stroke risk. As a neurosteroid, vitamin D influences brain development and function and immunomodulation and affects brain neuroplasticity. It supports many processes that maintain homeostasis in the body. As stroke is the second most common cause of death worldwide, more studies are needed to confirm the positive effects of vitamin D supplementation, its dosage at different stages of the disease, method of determination, and effect on stroke onset and recovery. Many studies on stroke survivors indicate that serum vitamin D levels only offer insignificant benefits and are not beneficial to recovery. This review article aims to highlight recent publications that have examined the potential of vitamin D supplementation to improve rehabilitation outcomes in stroke survivors. Particular attention has been paid to stroke prevention.

Vitamin-D Deficiency and Supplementation Altered the Network of the Coronary Arteries in a Rodent Model—In Situ Video Microscopic Technique

The aim of our study was to identify whether vitamin-D deficiency (VDD) can alter the geometry of the coronary-resistance-artery system. Male Wistar rats were divided into vitamin-D-deficient (VD−, n = 10) and vitamin-D-supplemented (VD+, n = 8) groups. After eight weeks, branches and segments of the left-anterior-descending-coronary-artery (LAD) network were analyzed by a video-microscopy technique. Segments were divided into 50 μm-long cylindrical ring units. VDD did not increase the number of morphological abnormalities. The number of segments did not differ between the groups (VD−: 210 and VD+: 224; pooled data of 8 networks). A larger lumen area of branches was found in VD+ group, while 1–4-order branches were lengthier in the VD− group. VD− rats had less rich coronary-resistance-artery networks in terms of 50 µm-long units. (VD−: 6365 vs. VD+: 6602; pooled data of 8 networks). VD+ animals were richer in the 100–350 µm outer diameter range, and VD− animals were richer in the 400–550 µm-diameter units. In VD− rats, 150–200 and 300 µm units were almost missing at higher flow distances from the orifice. Serum vitamin-D alterations caused by dietary changes can affect the geometry of the coronary-artery network, which may contribute to vitamin-D-dependent changes in cardiovascular mortality.

Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances

Vitamin D is a steroid hormone that plays a key role in the regulation of body homeostasis, including cardiovascular function. Although the chronic deficiency of vitamin D is associated with cardiovascular risk factors, as well as with an adverse prognosis, randomized controlled trials have failed in demonstrating that dietary vitamin D supplementation could ameliorate the prognosis of patients with cardiovascular diseases, and suggested that vitamin D deficiency is the expression of the effects of other determinants of cardiovascular risk. Thus, the supplementation of vitamin D is not sufficient to improve the cardiovascular risk profile and prognosis. Insulin resistance is a complex phenomenon that plays a key role in the pathogenesis of conventional cardiovascular risk factors. Interestingly, defects of vitamin D and insulin resistance have a superimposable epidemiological distribution. According to the common view, Insulin resistance is considered the direct or indirect consequence of vitamin D deficiency. However, it is also reasonable to speculate that the deficit or the impaired action of vitamin D, in some circumstances, could be the result of the same pathogenic mechanisms responsible of insulin resistance development. In this case, vitamin D deficiency could be considered an epiphenomenon of insulin resistance. Insulin resistance is a reversible condition, being possibly ameliorated by physical activity and hypocaloric diets. Notably, both physical exercise and energy-restricted dietary regimens are associated with an increase of vitamin D levels. These findings indicate that improving insulin resistance condition is a necessary step to ameliorate vitamin D supplementation-based strategies in cardiovascular prevention.

Circulating 25-hydroxy-vitamin D and the risk of cardiovascular diseases. Systematic review and meta-analysis of prospective cohort studies

AIMS

Circulating vitamin D is linked with the risk of cardiovascular disease (CVD). A meta-analysis has yet to explicitly explore correlation between vitamin D and the risk of CVD incidence and recurrent CVD. This meta-analysis examines the association between 25-hydroxy-vitamin D (25(OH)D) and the risk of CVD incidence (fatal, non-fatal, fatal and non-fatal combined events) and the risk of recurrent CVD (fatal, recurrent, and fatal and recurrent combined events). PROSPERO registration-CRD42021251483.

DATA SYNTHESIS

A total of 79 studies (46 713 CVD cases in 1 397 831 participants) were included in the meta-analysis, of which 61 studies examined the risk of CVD incidence events, and 18 studies examined risk of recurrent CVD events. The risk of CVD incidence events (RR = 1.34, 95% CI: 1.26-1.43, p < 0.001) and recurrent CVD events (RR = 1.86, 95% CI: 1.46-2.36, p < 0.001) was higher in the lowest than the highest category of circulating 25(OH)D. Dose-response analysis reported a linear association for every 10 ng/ml increment of 25(OH)D and non-fatal CVD incidence events (RR = 0.94; 95% CI = 0.89-0.98, p = 0.005), lower fatal recurrent CVD events (RR = 0.45; 95% CI = 0.32-0.62, p < 0.001) and lower combined recurrent CVD events (RR = 0.80; 95% CI = 0.65-0.97, p = 0.023). A non-linear association was observed between higher 25(OH)D and lower fatal CVD incidence events (P-nonlinear<0.001), lower combined CVD incidence events (P-nonlinear = 0.001), and lower non-fatal recurrent CVD events (P-nonlinear = 0.044).

CONCLUSIONS

The lowest category of circulating 25(OH)D was associated with a higher risk of CVD incidence events and recurrent CVD events.

Serum Level of Vitamin D Is Associated with Severity of Coronary Atherosclerosis in Postmenopausal Women

Background: Postmenopausal women experience rapid progression of coronary artery disease. Vitamin D deficiency appears to be a modifiable risk factor for cardiovascular diseases. This study aimed to analyze the impact of 25-hydroxyvitamin D3 (25(OH)D) level on the severity of coronary atherosclerosis and its potential cardioprotective effect in postmenopausal women. Material and Methods: The study prospectively recruited 351 women in postmenopausal age undergoing coronary angiography. The severity of coronary atherosclerosis was assessed using the Coronary Artery Surgery Study Score (CASSS). A level of 25(OH)D was measured with electrochemiluminescence. Results: Women with more severe coronary atherosclerosis have significantly lower 25(OH)D serum level (p = 0.0001). Vitamin D (β = -0.02; p = 0.016), hypertension (β = 0.44; p = 0.025), age (β = 0.02; p = 0.003), and history of MI (β = 0.63; p < 0.0001), were shown as CASSS determinants. Age, hyperlipidemia, and history of MI were found to determine the level of vitamin D (all p < 0.05). Women with a three-vessel disease hospitalized due to ACS, with a history of MI, hyperlipidemia and hypertension presented the lowest vitamin D level. Conclusions: Our study showed that lower serum 25(OH)D in postmenopausal women is associated with more significant stenosis in the coronary arteries. Therefore, we suggest considering low vitamin D level as a potential risk factor for coronary artery disease.

The Idiosyncratic Physiological Traits of the Naked Mole-Rat; a Resilient Animal Model of Aging, Longevity, and Healthspan

The subterranean-dwelling naked mole-rat (Heterocephalus glaber) is an extremophilic rodent, able to thrive in the harsh underground conditions of sub-Saharan Northeast Africa. This pelage-free mammal exhibits numerous unusual ecophysiological features including pronounced tolerance of thermolability, hypoxia, hypercapnia and noxious substances. As a mammal, the naked mole-rat provides a proof-of-concept that age-related changes in physiology are avoidable. At ages far beyond their expected lifespans given both their body size and/or the timing of early developmental milestones, naked mole-rats fail to exhibit meaningful changes in physiological health or demographic mortality. Lack of physiological deterioration with age is also evident in lean and fat mass, bone quality, and reproductive capacity. Rather, regardless of age, under basal conditions naked mole-rats appear to "idle on low" with their "shields up" as is manifested by low body temperature, metabolic rate, cardiac output and kidney concentrating ability, enabling better protection of organs and cellular function. When needed, they can nevertheless ramp up these functions, increasing cardiac output and metabolism 2-5 fold. Here we review many unusual aspects of their physiology and examine how these attributes facilitate both tolerance of the diverse suite of hostile conditions encountered in their natural milieu as well as contribute to their extraordinary longevity and resistance to common, age-related chronic diseases.

Nutritional Supplementation of Naturally Occurring Vitamin D to Improve Hemorrhagic Stroke Outcomes

Vitamin D deficiency, if left untreated, is associated with bone disorders, cardiovascular damage, and an increased risk of ischemic stroke. While there are various nutritional options for the natural intake of vitamin D, we hope to elucidate the potential mechanisms dietary vitamin D may play in hemorrhagic stroke pathology. This scoping review outlines findings from studies relevant to the biochemical activity of vitamin D, the impact of vitamin D deficiency on hemorrhagic stroke outcomes, and the potential benefit of nutritional vitamin D on hemorrhagic stroke outcomes. Here, we analyze the relevant factors that can lead to vitamin D deficiency, and subsequently, a higher risk of hemorrhagic stroke incidence with worsened subsequent outcomes. The neuroprotective mechanisms through which vitamin D works to attenuate hemorrhagic stroke onset and post-stroke outcomes have not yet been thoroughly examined. However, researchers have proposed several potential protective mechanisms, including reduction of blood brain barrier disturbance by inhibiting the production of reactive oxygen species, mitigation of inflammation through a reduction of levels of proinflammatory cytokines, and prevention of cerebral vasospasm and delayed cerebral ischemia following subarachnoid hemorrhage and intracerebral hemorrhage. While more research is needed and there are limitations to vitamin D supplementation, vitamin D as a whole may play a significant role in the dynamics of hemorrhagic stroke. Further research should focus on expanding our understanding of the neuroprotective capacity and mechanisms of vitamin D, as well as how vitamin D supplementation could serve as an effective course of treatment of hemorrhagic strokes.

Vitamin D Effects on Bone Homeostasis and Cardiovascular System in Patients with Chronic Kidney Disease and Renal Transplant Recipients

Poor vitamin D status is common in patients with impaired renal function and represents one main component of the complex scenario of chronic kidney disease-mineral and bone disorder (CKD-MBD). Therapeutic and dietary efforts to limit the consequences of uremia-associated vitamin D deficiency are a current hot topic for researchers and clinicians in the nephrology area. Evidence indicates that the low levels of vitamin D in patients with CKD stage above 4 (GFR < 15 mL/min) have a multifactorial origin, mainly related to uremic malnutrition, namely impaired gastrointestinal absorption, dietary restrictions (low-protein and low-phosphate diets), and proteinuria. This condition is further worsened by the compromised response of CKD patients to high-dose cholecalciferol supplementation due to the defective activation of renal hydroxylation of vitamin D. Currently, the literature lacks large and interventional studies on the so-called non-calcemic activities of vitamin D and, above all, the modulation of renal and cardiovascular functions and immune response. Here, we review the current state of the art of the benefits of supplementation with native vitamin D in various clinical settings of nephrological interest: CKD, dialysis, and renal transplant, with a special focus on the effects on bone homeostasis and cardiovascular outcomes.

An Assessment of Risk Factors for Insufficient Levels of Vitamin D during Early Infancy

Recent evidence suggests that breastfeeding may increase the risk of vitamin D deficiency in offspring. However, it is unclear whether increased risk results from breastfeeding alone, or whether it is associated together with other risk factors. This study surveyed 208 infant–mother dyads recruited by stratified random sampling in different districts of Hong Kong. Mothers were asked to complete a questionnaire on their demographics, history of risk behavior, and feeding practices. Peripheral blood samples were collected from infants to determine their vitamin D status. Among all infant participants, 70 were vitamin D insufficient or deficient. Being breastfed, being a girl, having a multiparous mother, and the use of sun cream were found to be the strongest risk factors for vitamin D insufficiency during infancy (all p < 0.05), after mutual adjustment. The cumulative risk model displayed a dose–response pattern between the number of risk factors and the risk of vitamin D insufficiency during this period. Our findings indicate the risk profile of infants with insufficient vitamin D. Guidelines and recommendations on healthy diet and lifestyle should be provided to mothers during the early stage of pregnancy to increase the likelihood of adequate levels of vitamin D in their offspring.

Trace Minerals, Vitamins and Nutraceuticals in Prevention and Treatment of COVID-19

Coronavirus disease 2019 (COVID-19) was first officially diagnosed in the city of Wuhan, China in January 2020. In reality, the disease was identified in December 2019 in the same city where patients began showing symptoms of pneumonia of unidentified origin. Very soon the disease became a global pandemic due to the suppression of information in the country of origin and inadequate testing for the COVID-19 virus. Currently, > 101 million people have been found positive for this virus and > 2.17 million people have died. There are no signs that COVID-19 is slowing down. This deadly virus affects multiple vital organs (lungs, heart, nervous system, blood, and immune system), yet its exact mechanism of pathophysiology remains obscure. Depending on the viral load, sick people often show symptoms of fever, cough, shortness of breath, coagulopathy, cardiac abnormalities, fatigue, and death. Great strides have been made in COVID-19 testing, thereby allowing timely therapeutic intervention. Currently, vaccines are on the market from Pfizer, Moderna and Astra Zeneca with limited supply. Phase III clinical trials are also underway from other manufacturers. In the current scenario, nutraceuticals and other phyto-mineral supplements appear to be promising alternative solutions for the prevention and treatment of COVID-19.

Association between serum vitamin D levels and venous thromboembolism (VTE): A systematic review and meta-analysis of observational studies

OBJECTIVE

Although many studies have attempted to unravel the relationship between vitamin D deficiency and the incidence of VTE, the results remained inconsistent. To address this discrepancy, we performed a systematic review and meta-analysis to precisely disentangle the relationship between serum vitamin D levels and VTE risk.

METHODS

The Web of Science, Scopus, PubMed/Medline, Embase, and Google Scholar databases were searched for all available observational studies that reported the risk of venous thromboembolism (VTE) based on serum vitamin D levels categories. The search was performed up to March 2020.

RESULTS

Seven studies were included. The overall analysis showed a significantly increased risk of VTE in subjects with low levels of serum vitamin D compared with those with normal vitamin D levels (RR = 1.34; 95% CI: 1.07-1.69; P = 0.011). In a sensitivity analysis, we did not observe a significant effect of any individual study on the combined effect sizes. Nevertheless, significant heterogeneity was present among the studies (Cochrane Q test, p = 0.018, I² = 61%). In the stratified analysis, low vitamin D levels were positively associated with an increased risk of VTE in prospective population-based studies (RR = 1.31; 95% CI: 1.06-1.61; P = 0.010) and in subjects below 60 years old (RR = 1.28; 95% CI: 1.07-1.54; P = 0.060).

CONCLUSION

our systematic review and meta-analysis showed that a low serum vitamin D level was indeed associated with an increased risk of VTE.

Prevalence of vitamin D deficiency in Egyptian patients with pregnancy-induced hypertension

Background Hypertensive disorders of pregnancy can cause severe maternal and fetal acute morbidity and mortality. Women with pre-eclampsia have been found to have alterations in calcium and vitamin D metabolism. There are conflicting results regarding the role of vitamin D deficiency in the development of pre-eclampsia. The aim was to compare 25 (OH) D level in patients with pre-eclampsia, eclampsia and normotensive pregnant women as well as to study the prevalence of Vitamin D deficiency among the 3 groups. Patients and methods Two hundred patients with pre-eclampsia, 100 with eclampsia and 200 normotensive pregnant controls were compared as regards vitamin D level. Results Mean 25(OH)D level was lower in the pre-eclampsia (14.8 ± 5.4 ng/mL) and in the eclampsia group (10.5 ± 1.6 ng/mL) than in the pregnant controls (19.5 ± 6.5 ng/mL) (P = 0.002). This difference was only significant between the eclampsia group and the pregnant controls (P = 0.02). All eclampsia cases had vitamin D insufficiency as compared to 17.5% in the pre-eclampsia group and 39.5% in the control group. Deficiency of vitamin D (<12 ng/mL) was 47.5% in the pre-eclampsia group, 80% in the eclampsia group and only 10.5% in the control group (P = 0.035). Conclusion Vitamin D deficiency is highly prevalent among Egyptian pregnant females. Our study supports the hypothesis that low vitamin D level can play a role in the development of pre-eclampsia and eclampsia. Thus, supplementation might prevent or delay the development of pre-eclampsia and eclampsia especially in patients at a high risk.

Improved metabolomic data-based prediction of depressive symptoms using nonlinear machine learning with feature selection

To solve major limitations in algorithms for the metabolite-based prediction of psychiatric phenotypes, a novel prediction model for depressive symptoms based on nonlinear feature selection machine learning, the Hilbert-Schmidt independence criterion least absolute shrinkage and selection operator (HSIC Lasso) algorithm, was developed and applied to a metabolomic dataset with the largest sample size to date. In total, 897 population-based subjects were recruited from the communities affected by the Great East Japan Earthquake; 306 metabolite features (37 metabolites identified by nuclear magnetic resonance measurements and 269 characterized metabolites based on the intensities from mass spectrometry) were utilized to build prediction models for depressive symptoms as evaluated by the Center for Epidemiologic Studies-Depression Scale (CES-D). The nested fivefold cross-validation was used for developing and evaluating the prediction models. The HSIC Lasso-based prediction model showed better predictive power than the other prediction models, including Lasso, support vector machine, partial least squares, random forest, and neural network. L-leucine, 3-hydroxyisobutyrate, and gamma-linolenyl carnitine frequently contributed to the prediction. We have demonstrated that the HSIC Lasso-based prediction model integrating nonlinear feature selection showed improved predictive power for depressive symptoms based on metabolome data as well as on risk metabolites based on nonlinear statistics in the Japanese population. Further studies should use HSIC Lasso-based prediction models with different ethnicities to investigate the generality of each risk metabolite for predicting depressive symptoms.

Impact of Nutrition on Telomere Health: Systematic Review of Observational Cohort Studies and Randomized Clinical Trials

Diet, physical activity, and other lifestyle factors have been implicated in the pathophysiology of several chronic diseases, but also in a lower total mortality and longer life expectancy. One of the mechanisms in which diet can reduce the risk of disease is with regard to its impact on telomeres. Telomere length (TL) is highly correlated to chronological age and metabolic status. Individuals with shorter telomeres are at higher risk of chronic diseases and mortality. Diet may influence TL by several mechanisms such as regulating oxidative stress and inflammation or modulating epigenetic reactions. The present systematic review aims to examine the results from epidemiologic and clinical trials conducted in humans evaluating the role of nutrients, food groups, and dietary patterns on TL. We also discuss the possible mechanisms of action that influence this process, with the perspective that TL could be a novel biomarker indicating the risk of metabolic disturbances and age-related diseases. The available evidence suggests that some antioxidant nutrients, the consumption of fruits and vegetables, and Mediterranean diet are mainly associated with longer telomeres. However, most of the evidence is based on high heterogenic observational studies and very few randomized clinical trials (RCTs). Therefore, the associations summarized in the present review need to be confirmed with larger prospective cohort studies and better-designed RCTs.

The effect of physical activity on dose-relationship between serum 25-hydroxyvitamin D and cardiovascular health events in older adults

BACKGROUND AND AIMS

Reverse J- or U-shaped associations between serum 25-hydroxyvitamin D (25[OH]D) concentrations and cardiovascular outcomes have been reported, which need clarifications in older adults. Physical activity, correlating with both serum 25[OH]D concentration and cardiovascular health, may have an effect on the dose-relationships.

METHODS AND RESULTS

At baseline, 2790 participants aged 65 years and over, free of vitamin D supplementation use, had assays for serum 25[OH]D concentrations and health related characteristics and measurements, were followed up for cardiovascular events and death by up to 7 and 15 years, respectively. The dose-response associations of serum 25[OH]D concentrations with cardiovascular events and mortality risk were examined using Cox regression models. After adjusting for physical activity and other covariates, serum 25[OH]D concentration was non-linearly associated with cardiovascular mortality risk (U-shaped, P = 0.009). According to the Institute of Medicine categories, the HR(95% CI) of cardiovascular mortality risk separately in deficient (<25 nmol/L), inadequate (25 to < 50 nmol/L) and potentially harmful (≥125 nmol/L) level was 1.67 (0.23, 12.01), 1.66 (1.25, 2.20) and 2.21 (0.30, 16.37), respectively. The risk of 25[OH]D inadequacy for cardiovascular mortality was significantly attenuated by increased physical activity, especially leisure activity (P for trend = 0.008 and 0.021, respectively). No significant finding was observed for incident cardiovascular events.

CONCLUSION

Both lower and higher serum 25[OH]D concentrations were associated with risk of cardiovascular mortality in Chinese community-dwelling older adults. Physical activity may attenuate the cardiovascular mortality risk of vitamin D inadequacy, but its role in individuals with higher 25[OH]D concentrations remains unclear.

Does vitamin D status predict weight gain or increase in waist circumference? Results from the longitudinal Health 2000/2011 Survey

OBJECTIVE

To investigate whether vitamin D status predicts weight gain or increase in waist circumference during the 11-year follow-up in general adult population.

DESIGN

A population-based longitudinal study.

SETTING

The study was conducted using data from the nationally representative Health 2000/2011 Survey. The analyses were based on regression models adjusted for sociodemographic and lifestyle factors.

PARTICIPANTS

Weight, waist circumference and vitamin D status (serum 25-hydroxyvitamin D concentration analysed with radioimmunoassay) were measured from 2924 participants aged 30-64 years at baseline.

RESULTS

In men, low vitamin D status at baseline predicted ≥10 % increase in waist circumference during the follow-up when adjusted for age only (OR for sufficient v. deficient S-25(OH)D 0·41; 95 % CI 0·25, 0·67; P for trend <0·01), but the association with weight gain was only borderline significant. After adjustment for potential confounders, low vitamin D status remained a significant predictor of increase in waist circumference, but the association with weight gain was further attenuated. In women, vitamin D status at baseline did not predict weight gain or increase in waist circumference.

CONCLUSIONS

Our results suggest that vitamin D insufficiency may be a risk factor of abdominal obesity among men but not among women. In men, it may also increase the risk of weight gain. Further studies are required to confirm these findings and examine potential mechanisms behind them. There is also a possibility that vitamin D is a biomarker of healthy lifestyle rather than an independent risk factor for obesity.

Menopause-Associated Lipid Metabolic Disorders and Foods Beneficial for Postmenopausal Women

Menopause is clinically diagnosed as a condition when a woman has not menstruated for one year. During the menopausal transition period, there is an emergence of various lipid metabolic disorders due to hormonal changes, such as decreased levels of estrogens and increased levels of circulating androgens; these may lead to the development of metabolic syndromes including cardiovascular diseases and type 2 diabetes. Dysregulation of lipid metabolism affects the body fat mass, fat-free mass, fatty acid metabolism, and various aspects of energy metabolism, such as basal metabolic ratio, adiposity, and obesity. Moreover, menopause is also associated with alterations in the levels of various lipids circulating in the blood, such as lipoproteins, apolipoproteins, low-density lipoproteins (LDLs), high-density lipoproteins (HDL) and triacylglycerol (TG). Alterations in lipid metabolism and excessive adipose tissue play a key role in the synthesis of excess fatty acids, adipocytokines, proinflammatory cytokines, and reactive oxygen species, which cause lipid peroxidation and result in the development of insulin resistance, abdominal adiposity, and dyslipidemia. This review discusses dietary recommendations and beneficial compounds, such as vitamin D, omega-3 fatty acids, antioxidants, phytochemicals—and their food sources—to aid the management of abnormal lipid metabolism in postmenopausal women.

[Vitamin D deficiency study in railway drivers.]

Heart rhythm disturbances are significant pathology and one of the reason of sudden cardiac arrest. Locomotive crew drivers are at high risk for cardiovascular diseases, including heart rhythm disturbances. Multiple factors as a professional stress, frequent night shifts, lack of insolation, diet disbalance, low physical activity, exposure to vibration and noise, and an unfavorable industrial climate. In this study it was found that railway-men are predisposed to vitamin D deficiency. This condition reduces resistance to stress and increases risk of unfavorable heart rhythm disturbances.

The association between circulating 25-hydroxyvitamin D and cardiovascular diseases: a meta-analysis of prospective cohort studies

BACKGROUND

There is a controversy about the association between vitamin D and cardiovascular diseases (CVDs). The effect of serum 25-OH-vitD on the risk of CVDs was evaluated.

METHODS

Major electronic databases including Scopus, Science Direct, and PubMed were searched. All prospective cohort studies on the relationship between vitamin D status and CVDs conducted between April 2000 and September 2017 were included, regardless language. The study participants were evaluated regardless of their age, sex, and ethnicity. The Newcastle-Ottawa Scale was used to assess the quality of the studies. Two investigators independently selected the studies and extracted the data. The designated effects were risk ratio (RR) and hazard ratio (HR). The random effects model was used to combine the results.

RESULTS

A meta-analysis of 25 studies with 10,099 cases of CVDs was performed. In general, a decrease in the level of vitamin D was associated with a higher relative risk of CVDs (incidence-mortality combined) (RR = 1.44, 95% CI: 1.24-1.69). This accounts for 54% of CVDs mortality rate (RR = 1.54, 95% CI: 1.29-1.84(. However, no significant relationship was observed between the vitamin D status and incidence of CVDs (RR = 1.18, 95% CI: 1-1.39). In general, low serum vitamin D level increased the risk of CVD by 44% (RR = 1.44, 95% CI: 1.24-1.69). It also increased the risk of CVD mortality (RR = 1.54, 95% CI: 1.29-1.84) and incidence rates (RR = 1.18, 95% CI: 1-1.39).

CONCLUSIONS

The findings showed that vitamin D deficiency increases the CVDs mortality rate. Due to the limited number of studies on patients of the both genders, further research is suggested to separately evaluate the effect of vitamin D status on CVD in men and women.

Vitamin D status and cardiovascular outcome

INTRODUCTION

Vitamin D is classically involved in maintaining bone and mineral health, but it has been shown to exert many extraskeletal functions, including pleiotropic effects on cardiovascular system.

MATERIALS AND METHOD

This review aims to summarize evidences in literature about vitamin D and cardiovascular outcome.

RESULTS AND CONCLUSIONS

Calcitriol or 1,25(OH)₂D, the active hormone, binds to the specific nuclear receptor VDR, which is expressed in rat and human heart and vasculature and has effects on myocardiocytes, smooth cells, and endothelial cells. 25-Hydroxy-vitamin D (25OHD) represents the biomarker of vitamin D levels and reflects vitamin D status. There is consistent evidence that low serum 25OHD levels are associated with increased risk of cardiovascular diseases, including hypertension, coronary artery disease, ischemic heart disease, heart failure, stroke, and type 2 diabetes. Randomized-controlled trials and Mendelian randomization studies so far have not succeeded in proving a benefit of vitamin D supplementation. However, the latter investigations are affected by some methodological limitations, and therefore, it is still unclear if vitamin D deficiency has a causative role in cardiovascular diseases or is rather a marker of poor health in chronic disease.

The combined presence of hypertension and vitamin D deficiency increased the probability of the occurrence of small vessel disease in China

BACKGROUND

The exact relationship between 25-hydroxyvitamin D [25(OH) D] levels and small vessel disease (SVD) are not clear in China. The aim of this study was to determine such the association between 25(OH) D and SVD in China.

METHODS

We retrospectively enrolled 106 patients with SVD and 115 controls between Jan 2017 and Dec 2017. All the subjects were categorized into three subgroups according to the level of 25 (OH) D: vitamin D deficiency (< 12 ng/ml), insufficiency (12-20 ng/ml) and sufficiency (> 20 ng/ml).

RESULTS

Among 106 SVD patients, 80 (75.5%) were men and the mean age was 61.6 ± 13.2 years. The deficiency of 25(OH) D was observed in 76 (71.7%) of SVD patients and 47 (40.9%) of controls (P = 0.001). Compared with controls, patients with SVD were more likely to be male, a stroke history, smokers, with hyperlipidemia, higher systolic and diastolic blood pressure and low-density lipoprotein, and lower of 25(OH)D level (P < 0.05). Logistic regression analysis revealed the level of 25 (OH) D as an independent predictor of SVD (OR 0.772, 95% CI 0.691-0.862, P = 0.001). Compared with the sufficient 25 (OH) D group, the ORs of SVD in deficient and insufficient 25(OH)D group were 5.609 (95% CI 2.006-15.683) and 1.077 (95% CI: 0.338-3.428) after adjusting for potential confounders, respectively. In hypertensives with vitamin D deficient and insufficient group compared with sufficient group, the ORs of SVD increased to 9.738 (95% CI 2.398-39.540) and 1.108 (95% CI 0.232-5.280), respectively (Pinteraction = 0.001).

CONCLUSION

We found significant associations between SVD and 25(OH)D deficiency. The combined presence of hypertension and vitamin D deficiency increased the probability of developing SVD. Our findings will warrant further prospective studies in the future.

Vitamin D-regulated osteocytic sclerostin and BMP2 modulate uremic extraskeletal calcification

We induced chronic kidney disease (CKD) with adenine in WT mice, mice with osteocyte-specific deletion of Cyp27b1, encoding the 25-hydroxyvitamin D 1(OH)ase [Oct-1(OH)ase-/-], and mice with global deletion of Cyp27b1 [global-1α(OH)ase-/-]; we then compared extraskeletal calcification. After adenine treatment, mice displayed increased blood urea nitrogen, decreased serum 1,25(OH)2D, and severe hyperparathyroidism. Skeletal expression of Cyp27b1 and of sclerostin and serum sclerostin all increased in WT mice but not in Oct-1α(OH)ase-/- mice or global-1α(OH)ase-/- mice. In contrast, skeletal expression of BMP2 and serum BMP2 rose in the Oct-1α(OH)ase-/- mice and in the global-1α(OH)ase-/- mice. Extraskeletal calcification occurred in muscle and blood vessels of mice with CKD and was highest in Oct-1α(OH)ase-/-mice. In vitro, recombinant sclerostin (100 ng/mL) significantly suppressed BMP2-induced osteoblastic transdifferentiation of vascular smooth muscle A7r5 cells and diminished BMP2-induced mineralization. Our study provides evidence that local osteocytic production of 1,25(OH)2D stimulates sclerostin and inhibits BMP2 production in murine CKD, thus mitigating osteoblastic transdifferentiation and mineralization of soft tissues. Increased osteocytic 1,25(OH)2D production, triggered by renal malfunction, may represent a "primary defensive response" to protect the organism from ectopic calcification by increasing sclerostin and suppressing BMP2 production.

Severity of Vitamin D Deficiency Predicts Mortality in Ischemic Stroke Patients

Background

Vitamin D (VD) deficiency is considered an independent risk factor for death due to cardiovascular events including ischemic stroke (IS). We assessed the hypothesis that decreased levels of 25-hydroxyvitamin D (25-OH-D) are associated with increased risk of mortality in patients with IS.

Methods

Serum 25-OH-D, intact parathyroid hormone (iPTH), and intact fibroblast growth factor 23 (iFGF23) levels were assessed in serum of 240 consecutive patients admitted within the 24 hours after the onset of IS. Mortality data was obtained from the local registry office.

Results

Only three subjects (1.3%) had an optimal 25-OH-D level (30-80 ng/mL), 25 (10.4%) had a mildly reduced (insufficient) level, 61 (25.4%) had moderate deficiency, and 151 (62.9%) had a severe VD deficiency. 20% subjects had secondary hyperparathyroidism. The serum 25-OH-D level was significantly lower than that in 480 matched subjects (9.9 ± 7.1 vs. 21.0 ± 8.7 ng/mL). Of all the patients, 79 (32.9%) died during follow-up observation (44.9 months). The mortality rates (per year) were 4.81 and 1.89 in a group with and without severe VD deficiency, respectively (incidence rate ratio: 2.52; 95% CI: 1.44–4.68). There was no effect of secondary hyperparathyroidism and iFGF23 levels on mortality rates. Age, 25 − OH − D < 10 ng/mL, and functional status (modified Rankin scale) were significant factors increasing the risk of death in multivariable Cox proportional hazard regression test.

Conclusions

Severe VD deficiency is an emerging, strong negative predictor for survival after IS, independent of age and functional status. VD supplementation in IS survivals may be considered due to high prevalence of its deficiency. However, it is uncertain whether it will improve their survival.

Vitamin D level is associated with severity of coronary artery atherosclerosis and incidence of acute coronary syndromes in non-diabetic cardiac patients

INTRODUCTION

Ischaemic heart disease is the main cause of death in developed countries. There are many modifiable risk factors associated with coronary heart disease (CAD). A growing number of studies point to vitamin D deficiency as a risk factor for heart attacks and the conditions associated with cardiovascular disease. This study aimed to analyse the relationship between the level of 25-hydroxyvitamin D (25(OH)D) and the severity of coronary artery atherosclerosis and to study 25(OH)D levels in non-diabetic patients hospitalised due to acute coronary syndrome and those diagnosed with stable CAD.

MATERIAL AND METHODS

oronary angiography was performed prospectively in 410 successive cardiac patients. The severity of coronary artery atherosclerosis was assessed according to the Coronary Artery Surgery Study Score (CASSS). The plasma 25(OH)D level was assessed with the electrochemiluminescence method.

RESULTS

The 25(OH)D level proved to be one of the significant determinants of the CASSS (p < 0.05). In subjects without significant lesions in the coronary arteries the 25(OH)D level was significantly higher compared to patients with one- to three-vessel coronary atherosclerosis (p < 0.05). A significantly higher 25(OH)D level was noted in patients diagnosed with stable CAD compared to patients hospitalised due to acute coronary syndrome (p < 0.01).

CONCLUSIONS

Patients with one- to three-vessel atherosclerosis have a significantly lower 25(OH)D level compared to patients without significant lesions in the coronary arteries. A lower 25(OH)D level was observed in patients hospitalised due to acute coronary syndrome compared to patients diagnosed with stable CAD.

Predictive Factors of Vitamin D Inadequacy among Older Adults in the United States

Optimal serum vitamin D levels are reported to be associated with many health benefits; however, few studies have determined predictive factors using national level data. An assessment of predictive factors for vitamin D inadequacy was conducted using National Health and Nutrition Examination Survey (NHANES) 2001-2006 data. Using the study sample including adults aged 40 years or more, data analysis was performed using the weighted multivariate logistic regression statistical procedure. The prevalence of vitamin D inadequacy (serum vitamin D <20 ng/ml) was 37.3%. Non-Hispanic Blacks were 6.4 times more likely to demonstrate vitamin D inadequacy compared to non-Hispanic Whites (OR_adj=6.351; 95% CI 5.338, 7.555; p<0.0001). Also, female gender was a significant predictor of vitamin D inadequacy (OR_adj=1.499; 95% CI 1.315, 1.708; p<0.0001) in multivariate models. Subjects who reported not taking vitamin D supplements in the past 30 days were more than twice as likely to be vitamin D inadequate compared with those who had taken dietary supplements containing vitamin D (OR_adj=2.225; 95% CI 1.903, 2.601; p<0.0001). In conclusion, the strongest predictor of vitamin D inadequacy was non-Hispanic Black ethnicity. Other potential predictors included smoking, non-use of vitamin D supplements, abnormal BMI, collecting samples in winter, female gender, perception of own health condition as not excellent, lack of health care, and older age. More focused interventions targeting groups of United States residents with vitamin D inadequacy are needed.

Vitamin D and cardiometabolic disorders: a review of current evidence, genetic determinants and pathomechanisms

Vitamin D deficiency has been implicated in the pathophysiology of cardiometabolic disorders including obesity, type 2 diabetes mellitus, cardiovascular diseases and polycystic ovary syndrome. Despite a large number of experimental and observational studies supporting a role for vitamin D in these pathologies, randomized controlled trials have reported little to no effect of vitamin D supplementation in the prevention or treatment of these disorders, although some results remain ambiguous. Polymorphisms in genes related to vitamin D metabolism, particularly in the vitamin D receptor and binding protein and the metabolizing enzyme 1-α-hydroxylase, have emerged as potential contributors to these divergent results. It is now becoming increasingly recognized that the effects and potential benefits of vitamin D supplementation may vary by several factors including vitamin D deficiency status, ethnicity and/or the presence of genetic variants, which affect individual responses to supplementation. However, these factors have seldom been explored in the available literature. Future trials should consider inter-individual differences and, in particular, should aim to clarify whether certain subgroups of individuals may benefit from vitamin D supplementation in the context of cardiometabolic health.

Vitamin D Status and Mortality: A Systematic Review of Observational Studies

Epidemiological evidence suggests that vitamin D deficiency is associated with increased mortality, but it is unclear whether this is explained by reverse causation, and if there are specific causes of death for which vitamin D might be important. We conducted a systematic review of observational studies investigating associations between circulating 25-hydroxyvitamin D (25(OH)D) concentration and all-cause or cause-specific mortality in generally healthy populations. Relevant studies were identified using PubMed and EMBASE searches. After screening 722 unique records and removing those that were ineligible, 84 articles were included in this review. The vast majority of studies reported inverse associations between 25(OH)D concentration and all-cause mortality. This association appeared to be non-linear, with progressively lower mortality with increasing 25(OH)D up to a point, beyond which there was no further decrease. There is moderate evidence that vitamin D status is inversely associated with cancer mortality and death due to respiratory diseases, while for cardiovascular mortality, there is weak evidence of an association in observational studies, which is not supported by the data from intervention or Mendelian randomization studies. The relationship between vitamin D status and other causes of death remains uncertain due to limited data. Larger long-term studies are required to clarify these associations.

Airway obstruction, serum vitamin D and mortality in a 33-year follow-up study

BACKGROUND AND OBJECTIVE

Chronic obstructive pulmonary disease and low vitamin D status predict mortality, but their combined effect on mortality remains inconclusive. We aimed to investigate a joint effect of airway obstruction and vitamin D status on mortality in a nationally representative cohort.

METHODS

We analysed data of 6676 Finnish adults participating between 1978 and 1980 in a national health examination survey, undergoing spirometry and having all necessary data collected. We followed them up in national registers through record linkage until 31 December 2011. We categorised the subjects with obstruction using the lower limit of normal (LLN) and the measured serum 25-hydroxyvitamin-D (s-25(OH)D) into tertiles.

RESULTS

Both obstruction and low s-25(OH)D independently predicted mortality in a multivariate model adjusted also for age, sex, smoking, education, leisure physical activity, body mass index, asthma and serum C-reactive protein. However, a statistically significant (p = 0.007) interaction emerged: the adjusted mortality HRs (95% CI's) for s-25(OH)D in tertiles among the subjects without and with obstruction were 1.00 (lowest), 0.96 (0.87-1.05) and 0.89 (0.81-0.98); and 1.00, 0.96 (0.71-1.31) and 0.57 (0.40-0.80), respectively.

CONCLUSIONS

In conclusion, obstruction and low s-25(OH)D predict mortality independently of each other. Our findings suggest that low vitamin D status might be particularly detrimental among subjects with obstruction.

A study of difference in serum 25-hydroxyvitamin D concentrations in patients with angiographically-defined coronary disease and healthy subjects

BACKGROUND

Cardiovascular disease (CVD) is one of the most important causes of death in developing countries. The current study evaluates the serum 25-hydroxyvitamin D (25OHD), phosphate and calcium levels in patients with angiographically-defined coronary artery disease (CAD) and healthy subjects in a sample population in northeastern Iran.

METHODS

There were 566 subjects aged between 20-80 years out of whom283 subjects with CAD were divided into two study groups based on their angiogram results; those with > 50% stenosis of one or more coronary arteries and those with ≤ 50% stenosis. Serum 25OHD levels and anthropometric parameters were measured for all subjects.

RESULTS

There were approximately 53% (n = 303) males and 47% (n = 269) females in the population sample. We found that crude serum 25OHD concentrations were significantly higher in both the Angio^- (21.6 ± 11.8 ng/ml) and Angio⁺ (21.3 ± 10.2 ng/ml) groups compared to the control subjects (16.4 ± 9.5 ng/ml) (P < 0.001).

CONCLUSION

The findings show that 25OHD state could be a risk factor for CAD, although this would need to be explored further, taking the potential confounding effects of diet into account in future studies.

Vitamin D ameliorates impaired wound healing in streptozotocin-induced diabetic mice by suppressing NF-κB-mediated inflammatory genes

Diabetic wounds are characterized by delayed wound healing due to persistent inflammation and excessive production of reactive oxygen species. Vitamin D, which is well acknowledged to enhance intestinal calcium absorption and increase in plasma calcium level, has recently been shown to display beneficial effects in various vascular diseases by promoting angiogenesis and inhibiting inflammatory responses. However, the role of Vitamin D in diabetic wound healing is still unclear. In the present study, we investigated the role of Vitamin D in cutaneous wound healing in streptozotocin (STZ)-induced diabetic mice. Four weeks after injection of STZ, a full thickness excisional wound was created with a 6-mm diameter sterile biopsy punch on the dorsum of the mice. Vitamin D was given consecutively for 14 days by intraperitoneal injection. Vitamin D supplementation significantly accelerated wound healing in diabetic mice and improved the healing quality as assessed by measuring the wound closure rate and histomorphometric analyses. By monitoring the level of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL) 6 (IL-6), IL-1β) in the wounds, reduced inflammatory response was found in VD treatment group. Furthermore, nuclear factor κB (NF-κB) pathway was found to be involved in the process of diabetic wound healing by assessing the relative proteins in diabetic wounds. Vitamin D supplementation obviously suppressed NF-κB pathway activation. These results demonstrated that Vitamin D improves impaired wound healing in STZ-induced diabetic mice through suppressing NF-κB-mediated inflammatory gene expression.

Investigation of genetic variation and lifestyle determinants in vitamin D levels in Arab individuals

Background

Differences in the concentrations of circulating 25-hydroxyvitamin D [25(OH)D] are associated with a wide range of health outcomes; however, most studies on genetic variants that impact 25(OH)D levels have been conducted in European populations. Here we aimed to identify common genetic variants that affect vitamin D concentrations in individuals of self-reported Arab ethnicity.

Methods

The study included 1151 Arab subjects living in Kuwait. Common variants of single-nucleotide polymorphisms and genes previously associated with vitamin D levels, such as GC, PDE3B, CYP2R1, and NADSYN1, were genotyped. Raw vitamin D level data were corrected for age, body mass index, and sex and then normalized. Regression tree analyses were performed to identify the impact of genetic variants on vitamin D levels.

Results

Compared with other gene variants, the GC gene variants exhibited the greatest impact on vitamin D levels in our study population, of which rs2298850 had the lowest p value (0.003). Individuals homozygous for the derived allele C had lower vitamin D levels. Analyses of the interaction between the number of years for which the subjects had lived in Kuwait and genetic variation in the GC gene showed that those with the CC genotype of rs2298850 who had lived in Kuwait for < 51 years had a mean 25(OH)D level of 10 ng/ml, whereas those who were homozygous for the ancestral allele had a mean 25(OH)D level of 17 ng/ml. Furthermore, subjects who had lived in Kuwait for > 51 years had higher vitamin D levels (mean 28 ng/ml) regardless of the genotype of their GC gene.

Conclusions

The GC gene may play a major role in determining vitamin D levels in Arab populations.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1396-8) contains supplementary material, which is available to authorized users.

Vitamin D and Heart Failure

PURPOSE

Vitamin D is principally known for its role in calcium homeostasis, but preclinical studies implicate multiple pathways through which vitamin D may affect cardiovascular function and influence risk for heart failure. Many adults with cardiovascular disease have low vitamin D status, making it a potential therapeutic target. We review the rationale and potential role of vitamin D supplementation in the prevention and treatment of chronic heart failure.

RECENT FINDINGS

Substantial observational evidence has associated low vitamin D status with the risk of heart failure, ventricular remodeling, and clinical outcomes in heart failure, including mortality. However, trials assessing the influence of vitamin D supplementation on surrogate markers and clinical outcomes in heart failure have generally been small and inconclusive. There are insufficient data to recommend routine assessment or supplementation of vitamin D for the prevention or treatment of chronic heart failure. Prospective trials powered for clinical outcomes are warranted.

Relationship Between Dietary Vitamin D and Deaths From Stroke and Coronary Heart Disease: The Japan Collaborative Cohort Study

BACKGROUND AND PURPOSE

There is growing evidence about the importance of vitamin D for cardiovascular health. Therefore, we examined the relationship between dietary vitamin D intake and risk of mortality from stroke and coronary heart disease in Japanese population.

METHODS

A prospective study encompassing 58 646 healthy Japanese adults (23 099 men and 35  547 women) aged of 40 to 79 years in whom dietary vitamin D intake was determined via a self-administered food frequency questionnaire. The median follow-up period was 19.3 years (1989-2009). The hazard ratios and 95% confidence intervals of mortality were calculated using categories of vitamin D intake.

RESULTS

During 965 970 person-years of follow-up, 1514 stroke and 702 coronary heart disease deaths were documented. Vitamin D intake was inversely associated with risk of mortality from total stroke especially intraparenchymal hemorrhage but not from coronary heart disease; the multivariable hazard ratios (95% confidence intervals) for the highest (≥440 IU/d) versus lowest (<110 IU/D) categories of vitamin D intake were 0.70 (0.54-0.91; P for trend=0.04) for total stroke and 0.66 (0.46-0.96; P for trend=0.04) for intraparenchymal hemorrhage.

CONCLUSIONS

Dietary vitamin D intake seems to be inversely associated with mortality from stroke.

No Evidence for Lower Levels of Serum Vitamin D in the Presence of Hepatic Steatosis. A Study on the Portuguese General Population

Introduction and aims: Nonalcoholic fatty liver disease (NAFLD) has become highly prevalent, paralleling the pandemic of obesity and diabetes, and represents an important burden. Nutrition knowledge is fundamental, in prevention, evolution and treatment of NAFLD. Association of low serum levels of vitamin D (VD) with several diseases, including NAFLD, has been emphasized in the last decade. We evaluated how serum levels of VD correlate with the presence of hepatic steatosis, and VD intake, in a random sample of the Portuguese adult population. Methods: Participants underwent a dietary intake inquiry, using a semi-quantitative food frequency questionnaire representative of the usual intake over the previous year. Anthropometric measures, blood tests and ultrasound were done. Hepatic steatosis was quantified according to Hamaguchi's ultrasonographic score (steatosis defined by a score ≥ 2). Results: We recruited 789 adult individuals, 416 males (52.7%), mean age of 49.9 ± 17.0 years (18-79). Prevalence of hepatic steatosis was 35.5%, and after exclusion of excessive alcohol consumption, 28.0%. Mean VD serum levels were 26.0 ± 9.8 ng/ml and 68.4% participants had serum VD levels below 30 ng/ml. Mean serum levels of VD were not significantly different between participants with steatosis vs. no steatosis: 25.2±8.7 vs. 26.4±10.3 ng/ml, respectively (p=0.071). There was no correlation between VD serum levels and VD intake, measured by the FFQ, r=0.075 (p= 0.383). Conclusions: In spite of a high prevalence rate, there was no evidence that decreased VD serum levels were associated with hepatic steatosis. No significant correlation was found between VD dietary ingestion and VD serum levels.

Vitamin D and regulation of vascular cell function

Vitamin D deficiency is linked to pathogenesis of many diseases including cardiovascular, cancer, and various eye diseases. In recent years, important roles for vitamin D in regulation of immune function, inflammation, angiogenesis, and aging have been demonstrated. Thus, vitamin D and its analogs have been evaluated for the treatment of various types of cancer and chronic diseases. We have previously shown that the active form of vitamin D [1,25(OH)₂D₃] is a potent inhibitor of angiogenesis. This activity is consistent with the important role proposed for vitamin D and its analogs in the mitigation of tumor growth through inhibition of angiogenesis. Here, we review the important nutritional value of vitamin D and the abnormalities linked to its deficiency. We will explore its potential role as a regulator of angiogenesis and vascular cell function and the role vitamin D receptor (VDR) expression plays in these activities during vascular development and neovascularization. Our studies have established an important role for 1,25(OH)₂D₃ and VDR in the regulation of perivascular supporting cell function. In addition, the interaction of 1,25(OH)₂D₃ and VDR is essential for these activities and inhibition of neovascularization. Delineating the signaling pathways involved and identification of genes that are the target of 1,25(OH)₂D₃ regulation in vascular cells will allow us to identify novel pathways that are targets for regulation of vascular function and angiogenesis.

Low vitamin D status in relation to cardiovascular disease and mortality in Swedish women - Effect of extended follow-up

BACKGROUND AND AIMS

The impact of vitamin D concentrations on subsequent cardiovascular disease (CVD) and overall mortality has been generally examined for periods under two decades. The magnitude of the association may depend on follow-up length. We aimed to investigate the relationship between baseline vitamin D and risk of total CVD, stroke and all-cause mortality over three decades of follow-up. Secondly, we aimed to assess how follow-up affects the associations.

METHODS AND RESULTS

Concentrations of 25-hydroxyvitamin D (25D) were measured in a population-based sample of 1227 middle-aged women using serum collected at baseline and categorized into low (lowest 25D quartile) vs high 25D status (upper three 25D quartiles). Hazard ratio (HR) of the endpoints was estimated for low 25D. The impact of follow-up was examined in intermediary analyses where follow-up was interrupted up to four times, each time decreasing it by five years. There were 596 cardiovascular events and 635 participants died. During the first 17 years, the low 25D group experienced a 29% higher CVD risk and 3.3-fold higher stroke risk after accounting for confounders. Longer follow-up diminished significantly these risks and 25D status had no contribution at 32 years. For mortality, the decline over time was less dramatic, with HR = 1.96 (1.25; 3.08) at 17 years and HR = 1.42 (1.17; 1.72) at 37 years.

CONCLUSION

Low 25D status increased the risk for all endpoints, but a lengthy follow-up diminished these risks towards the null. The impact of follow-up depends on the outcome. Future studies of 25D and disease should use repeated 25D assessments.

Serum 25-hydroxyvitamin D and the risk of stroke in Hong Kong Chinese

Low vitamin D levels have been associated with various cardiovascular diseases; however, whether it is associated with stroke remains inconclusive. We aimed to evaluate the association between serum 25-hydroxyvitamin D and risk of stroke. We conducted a cohort study consisting of 3,458 participants from the Hong Kong Osteoporosis Study aged ≥45 at baseline, examined between 1995 and 2010 and followed up using electronic medical records. Ischaemic and haemorrhagic stroke were defined using the ICD-9 code. In multivariable Cox-proportional hazard regression, quintiles 1 and 4 were significantly associated with increased risk of stroke when compared to the highest quintile (Quintile 1: HR, 1.78; 95 % CI, 1.16–2.74 and quintile 4: HR, 1.61; 95 % CI, 1.07–2.43). A similar association was observed in both men and women. In subgroup analysis, the association was specifically observed for ischaemic stroke, but not haemorrhagic stroke. Using a penalized regression spline, the association between vitamin D and risk of stroke was in a reverse J-shape, with the lowest risk of stroke being observed at 25(OH)D levels between 70 and 80 nmol/l. In conclusion, a low vitamin D level is associated with increased risk of ischaemic stroke; however, whether high vitamin D level is also associated with increased risk of stroke requires further study.

Supplementary Material to this article is available at www.thrombosis-online.com.

Vitamin D and the lung

Vitamin D metabolism is complex and its deficiency has proven to be deleterious in bone health, and to have significant effects on the immune and cardiovascular systems. Vitamin D has also been associated with pulmonary diseases outcomes. This review will focus on vitamin D metabolism, and studies performed mostly in children with asthma or Cystic Fibrosis.

Age and Gender Differences in the Association between Serum 25-Hydroxyvitamin D and Stroke in the General US Population: The National Health and Nutrition Examination Survey, 2001-2006

BACKGROUND

Previous findings on the association between serum 25(OH)D level and stroke have been controversial. We aimed to examine whether these controversial findings could be possibly due to difference in study participant characteristics, especially age and gender differences in these studies, by analyzing the data from a representative sample of the general US population.

METHODS

Data of 13,642 adults 20 years or older who participated in the 2001-2006 National Health and Nutrition Examination Survey were analyzed in this study. Serum 25(OH)D was used to reflect vitamin D status. Stroke history was self-reported using questionnaires. Unadjusted and adjusted logistic regression models were fitted using SAS survey procedures to investigate the associations between 25(OH)D level and stroke for the pooled sample and age-gender subgroups (men versus women, <50 years old versus ≥50 years old), respectively.

RESULTS

After adjusting for demographic and lifestyle covariates, vitamin D deficiency (defined as serum 25(OH)D < 12 ng/mL) was significantly associated with increased risk of stroke (adjusted odds ratio [OR] = 1.62, 95% confidence interval [CI] = 1.11, 2.36), and higher vitamin D levels were significantly associated with reduced risk of stroke (adjusted OR = .70, 95% CI = .51, .96). The association between high levels of serum 25(OH)D and stroke was particularly evident among young females (age ≤20 years to <50 years) (adjusted OR = .26, 95% CI = .14, .49).

CONCLUSIONS

The findings add to the evidence suggesting maintaining ideal 25(OH)D levels may reduce the risk of stroke among US adults, particularly in adult women younger than 50 years.