Vitamin D insufficiency in congestive heart failure: why and what to do about it?

Vitamin D and cardiovascular diseases

Vitamin D has an established role in calcium homeostasis but its deficiency is emerging also as a new risk factor for cardiovascular disease (CVD). In particular, several epidemiological and clinical studies have reported a close association between low vitamin D levels and several cardiovascular risk factors and major CVDs, such as coronary artery disease, heart failure, and cardiac arrhythmias. In all these clinical settings, vitamin D deficiency seems to predispose to increased morbidity, mortality, and recurrent cardiovascular events. Despite this growing evidence, interventional trials with supplementation of vitamin D in patients at risk of or with established CVD are still controversial. In this chapter, we summarize the currently available evidence on the links between vitamin D deficiency and major cardiovascular risk factors and CVD, in terms of both clinical relevance and potential therapeutic implications.

Association between vitamin D and cardiovascular health: Myth or Fact? A narrative review of the evidence

Vitamin D deficiency is prevalent worldwide. Since the discovery of the expression of vitamin D receptor in ventricular cardiomyocytes, fibroblasts, and blood vessels, there has been a growing body of literature assessing the link between vitamin D status and cardiovascular health from one side, and the effect of vitamin D supplementation on prevention of cardiovascular diseases from the other side. In this review, we summarized studies highlighting the role of vitamin D on cardiovascular health, namely atherosclerosis, hypertension, heart failure, and metabolic syndrome, a recognized significant risk factor for cardiovascular diseases. Studies showed discrepancies between findings from cross-sectional and longitudinal cohorts and those from interventional trials, but also between one outcome and another. Cross-sectional studies found a strong association between low 25 hydroxyvitamin D (25(OH)D3) and acute coronary syndrome, and heart failure. These findings encouraged the promotion for vitamin D supplementation as a preventive measure for cardiovascular diseases in the elderly, namely in women. This fact, however, turned out into a myth with the results of large interventional trials that did not show any benefit from vitamin D supplementation in reducing ischemic events, heart failure or its outcomes, or hypertension. Although some clinical studies showed beneficial effect of vitamin D supplementation on insulin sensitivity and metabolic syndrome, this effect was not consistent across all studies.

Vitamin D and Vascular Disease

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. Vitamin D deficiency has been identified as a potential risk factor for a number of diseases unrelated to the classical skeletal pathophysiology, such as cancer and CVD, but the effects of vitamin D supplementation are less clear. Purpose of this narrative review is to discuss the evidence suggesting an association between vitamin D status and CVD as well as the results of supplementation studies. Vitamin D deficiency has been associated with CVD risk factors such as hypertension, dyslipidemia and diabetes mellitus as well as with cardiovascular events such as myocardial infarction, stroke and heart failure. While vitamin D deficiency might contribute to the development of CVD through its association with risk factors, direct effects of vitamin D on the cardiovascular system may also be involved. Vitamin D receptors are expressed in a variety of tissues, including cardiomyocytes, vascular smooth muscle cells and endothelial cells. Moreover, vitamin D has been shown to affect inflammation, cell proliferation and differentiation. While observational studies support an association between low plasma vitamin D levels and increased risk of CVD, Mendelian randomization studies do not support a causal association between the two. At present, high quality randomized trials do not find evidence of significant effects on CVD endpoints and do not support supplementation of vitamin D to decrease CVD events.

Social and environmental risks as contributors to the clinical course of heart failure

Heart failure is a major contributor to healthcare expenditures. Many clinical risk factors for the development and exacerbation of heart failure had been reported, including diabetes, renal dysfunction, and respiratory disease. In addition to these clinical parameters, the effects of social factors, such as occupation or lifestyle, and environmental factors may have a great impact on disease development and progression of heart failure. However, the current understanding of social and environmental factors as contributors to the clinical course of heart failure is insufficient. To present the knowledge of these factors to date, this comprehensive review of the literature sought to identify the major contributors to heart failure within this context. Social factors for the risk of heart failure included occupation and lifestyle, specifically in terms of the effects of specific occupations, occupational exposure to toxicities, work style, and sleep deprivation. Socioeconomic factors focused on income and education level, social status, the neighborhood environment, and marital status. Environmental factors included traffic and noise, air pollution, and other climate factors. In addition, psychological stress and behavior traits were investigated. The development of heart failure may be closely related to these factors; therefore, these data should be summarized for the context to improve their effects on patients with heart failure. The present study reviews the literature to summarize these influences.

Vitamin D and Cardiovascular Disease, with Emphasis on Hypertension, Atherosclerosis, and Heart Failure

Vitamin D deficiency is the most common nutritional deficiency, affecting almost one billion people worldwide. Vitamin D is mostly known for its role in intestinal calcium absorption and bone mineralization. However, the observation of seasonal changes in blood pressure and the subsequent identification of vitamin D receptor (VDR) and 1α-hydroxylase in cardiomyocytes, as well as endothelial and vascular smooth muscle cells, implicated a role of vitamin D in the cardiovascular system. Animal studies provided compelling evidence that vitamin D signaling is essential for cardiovascular integrity, especially for the regulation of vascular tone and as an antifibrotic and antihypertrophic signaling pathway in the heart. In addition, observational studies reported an association between vitamin D deficiency and risk of hypertension, atherosclerosis, and heart failure. However, recent clinical intervention studies failed to prove the causal relationship between vitamin D supplementation and beneficial effects on cardiovascular health. In this review, we aim to highlight our current understanding of the role of vitamin D in the cardiovascular system and to find potential explanations for the large discrepancies between the outcome of experimental studies and clinical intervention trials.

Vitamin D toxicity in a pediatric toxicological referral center; a cross-sectional study from Iran

Background

Vitamin D is an essential element for body health with its supplements generally administered to prevent vitamin D deficiency. Since these supplements are available in domestic settings, vitamin D toxicity may happen in children.

Methods

All children younger than 12 years who presented to the pediatric emergency department of Loghman Hakim Hospital, Tehran, Iran with history of ingestion of more than 1500 IU/day of vitamin D supplements were enrolled. Patients’ demographic data, on-presentation signs and symptoms, laboratory findings, treatments given, and outcome were evaluated.

Result

Fifteen patients presented during the study period. Their mean age was 46.53 ± 10.14 months and 12 (80%) were girls. All of them had unintentionally ingested vitamin D. Mean ingested dose was 406700.7 ± 227400.1 IU. In eight patients (53.3%), 25 hydroxy vitamin D level was more than 100 ng/mL. One patient experienced hypercalcemia while all of them were asymptomatic and discharged without complications. There was no significant difference between patients with and without high levels of 25 OH vitamin D regarding lab tests, toxicity course, and outcome.

Conclusions

It seems that acute vitamin D toxicity is a benign condition in our pediatric population which may be due to high prevalence of vitamin D deficiency in Iran.

Benefits of multiple micronutrient supplementation in heart failure: A comprehensive review

BACKGROUND

Multiple micronutrient supplementation has been suggested to have a role on health outcomes in patients with heart failure (HF), but the evidence is inconclusive.

OBJECTIVE

To elucidate the role of multiple micronutrient supplementation in heart failure we performed a comprehensive review of the literature.

METHODS AND RESULTS

The search in databases included PUBMED (until June 2018) to detect randomized controlled trials (RCTs) and meta-analyzes that investigated the impact of micronutrient supplementation in HF.

RESULTS

With more than 2357 titles and abstracts reviewed, we included only the studies suitable for the final review. Whether alone or in combination, micronutrients have been found to improve the health outcomes of patients with HF by improving symptoms, work capacity and left ventricular ejection fraction (LVEF), thus increasing the quality of life in these patients.

CONCLUSION

Future studies are needed to document the effects of multiple micronutrient associations in order to include them in nutritional guidelines to increase survival and to improve quality of life in patients with heart failure.

Vitamin D deficiency and supplementation in critical illness-the known knowns and known unknowns

The burgeoning literature on vitamin D deficiency and supplementation over the past decade or so has generated a greater understanding of some areas but also an appreciation of the many areas of equipoise. This is particularly relevant in the field of critical care with the heterogeneous patient populations, the severity and duration of illness and the frequency of comorbid conditions.

This review aims to summarise the current knowledge base of vitamin D deficiency within the context of critical illness—“the known knowns”—and also highlight the areas of recognised uncertainty—“the known unknowns”. It acknowledges the fact that there may well be other knowledge gaps of clinical relevance of which we are currently unaware—“the unknown unknowns”.

Vitamin D deficiency and risk of cardiovascular diseases: a narrative review

Vitamin D, a fat-soluble prohormone, has wide-ranging roles in the regulation of many physiological processes through their interactions with the vitamin D receptors (VDR). It plays a major role in bones and calcium metabolism. Vitamin D deficiency is not uncommon and it has been associated with many health-related issues, including skeletal and non-skeletal complications. The association of low vitamin D and cardiovascular diseases and risk factors has been explored in both animal and human studies. However, studies and trials on the effect of vitamin D supplementation on cardiovascular risk factors and hypertension are conflicting with inconsistent results. Therefore, large, well-powered randomized controlled trials are warranted. If successful, supplementation with easy and low-cost vitamin D can impact our health positively. Here, we summarized the evidence for the association of vitamin D, cardiovascular diseases and risk factors, including coronary artery diseases, stroke, and hypertension, and mortality, with special consideration to resistant hypertension.

Genetic polymorphisms of vitamin D3 metabolizing CYP24A1 and CYP2R1 enzymes in Turkish patients with ischemic stroke

Objective Vitamin D deficiency is known as an important risk factor in pathogenesis of atherosclerosis, which contributes to stroke development. Genetic variations including single nucleotide polymorphisms (SNPs) in enzymes involved in vitamin D metabolism can affect susceptibility to the development of stroke. Therefore, the objective of this study was to investigate the association between polymorphisms of vitamin D metabolizing enzymes (rs927650 SNP in CYP24A1, and rs10741657 SNP in CYP2R1 genes,) and ischemic stroke risk in Turkish population. Materials and methods To test this hypothesis, we designed a case-control study which consisted of 256 ischemic stroke patients and 132 controls. Genotypes were determined by PCR-RFLP technique. Results No significant differences were found between patients and controls in terms of CYP24A1 rs927650 and CYP2R1 rs10741657 genotype frequencies. Polymorphic allele frequencies of CYP24A1 rs927650 and CYP2R1 rs10741657 were 0.414 and 0.660 in stroke patients, respectively. Conclusion This is the first study conducted regarding the association of CYP24A1 rs927650 and CYP2R1 rs10741657 genetic polymorphisms and ischemic stroke risk. The polymorphic genotypes of these polymorphisms, together with hypertension, diabetes, smoking, and obesity, were found as significant risk factors for ischemic stroke.

Vitamin D supplementation and bone turnover in advanced heart failure: the EVITA trial

Low vitamin D status is common in patients with heart failure and may influence bone health. A daily vitamin D dose of 4000 IU (moderately high dose) for 3 years had however no effect on parameters of bone metabolism, even in patients with very low vitamin D status.

INTRODUCTION

Low vitamin D status is common in patients with heart failure (HF) and has been related to disturbed bone turnover. The present study investigated the effect of a daily vitamin D₃ dose of 4000 IU on bone turnover markers (BTMs) in patients with advanced HF and 25-hydroxyvitamin D (25OHD) concentrations < 75 nmol/L.

METHODS

In this pre-specified secondary analysis of a randomized controlled trial, we assessed in 158 male HF patients (vitamin D group: n = 80; placebo group: n = 78) between-group differences in calciotropic hormones (25OHD, 1,25-dihydroxyvitamin D [1,25(OH)₂D], intact parathyroid hormone [iPTH]), and BTMs (cross-linked C-telopeptide of type I collagen, bone-specific alkaline phosphatase, undercarboxylated osteocalcin). Comparisons were performed at the end of a 3-year vitamin D supplementation period with adjustments for baseline values.

RESULTS

Compared with placebo, vitamin D increased 25OHD on average by 54.3 nmol/L. At study termination, 25OHD and 1,25(OH)₂D were significantly higher (P < 0.001 and P = 0.007, respectively), whereas iPTH tended to be lower in the vitamin D group than in the placebo group (P = 0.083). BTMs were initially within their reference ranges and did not differ significantly between groups at study termination, neither in the entire study cohort nor when data analysis was restricted to the subgroup of patients with initial 25OHD concentrations < 30 nmol/L (n = 54) or to patients with initial hyperparathyroidism (n = 65) (all P values > 0.05).

CONCLUSIONS

A daily vitamin D₃ dose of 4000 IU did not influence BTMs. Data indicate that vitamin D supplementation will not lower bone turnover in male patients with heart failure.

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.

Synergistic effect of low K and D vitamin status on arterial stiffness in a general population

Both vitamins K and D are nutrients with pleiotropic functions in human tissues. The metabolic role of these vitamins overlaps considerably in calcium homeostasis. We analyzed their potential synergetic effect on arterial stiffness. In a cross-sectional study, we analyzed aortic pulse wave velocity (aPWV) in 1023 subjects from the Czech post-MONICA study. Desphospho-uncarboxylated matrix γ-carboxyglutamate protein (dp-ucMGP), a biomarker of vitamin K status, was measured by sandwich ELISA and 25-hydroxyvitamin D3 (25-OH-D3) by a commercial immunochemical assay. In a subsample of 431 subjects without chronic disease or pharmacotherapy, we detected rs2228570 polymorphism for the vitamin D receptor. After adjustment for confounders, aPWV was independently associated with both factors: dp-ucMGP [β-coefficient(S.E.M.)=13.91(4.87); P=.004] and 25-OH-D3 [0.624(0.28); P=.027]. In a further analysis, we divided subjects according to dp-ucMGP and 25-OH-D3 quartiles, resulting in 16 subgroups. The highest aPWV had subjects in the top quartile of dp-ucMGP plus bottom quartile of 25-OH-D3 (i.e., in those with insufficient status of both vitamin K and vitamin D), while the lowest aPVW had subjects in the bottom quartile of dp-ucMGP plus top quartile of 25-OH-D3 [9.8 (SD2.6) versus 6.6 (SD1.6) m/s; P<.0001]. When we compared these extreme groups of vitamin K and D status, the adjusted odds ratio for aPWV≥9.3 m/s was 6.83 (95% CI:1.95-20.9). The aPWV was also significantly higher among subjects bearing the GG genotype of rs2228570, but only in those with a concomitantly poor vitamin K status. In conclusion, we confirmed substantial interaction of insufficient K and D vitamin status in terms of increased aortic stiffness.

Is Vitamin D Deficiency Associated With Heart Failure? A Review of Current Evidence

An estimated 1 billion people worldwide have deficient or insufficient levels of vitamin D. Even more alarming is the association of vitamin D deficiency with many types of diseases, particularly heart failure (HF). Hypovitaminosis D has been observed to be highly prevalent in the HF community with rates varying from approximately 80% to 95%. Higher rates of deficiency have been linked to winter months, in patients with protracted decompensated HF, darker skin pigmentation, and higher New York Heart Association (NYHA) classes. In fact, some data suggest vitamin D deficiency may even be an independent predictor of mortality in patients with HF. Traditionally obtained through UV exposure and activated in the liver and then the kidneys, vitamin D is classified as a vitamin but functions as a steroid hormone. The hormone acts through the vitamin D receptor (VDR), which is expressed in vascular smooth muscle cells, renal juxtaglomerular cells, and most interestingly, cardiac myocytes. Studies have shown that the association between vitamin D deficiency and HF often manifests in the structural components of cardiac myocytes and/or through alterations of the neurohormonal cascade. In addition, vitamin D may also act rapidly through intracellular nongenomic receptors that alter cardiac contractility. Unfortunately, prospective vitamin D supplementation trials show mixed results. In rat models, successful correction of deficiency was associated with reductions in ventricular hypertrophy. In humans, however, echocardiographic dimensions did not change significantly. These results bring into questions whether vitamin D is a risk factor for HF, a marker of HF disease severity, or has a true pathologic role. This article provides a thorough review of vitamin D deficiency etiology, prevalence, and possible pathophysiologic role in HF. Furthermore, we carefully review prospective trials on vitamin D therapy in HF. We believe more trials on vitamin D therapy in HF need to be conducted before any conclusions can be drawn.

Interplay of vitamin D and metabolic syndrome: A review

Vitamin D deficiency is a worldwide public health problem. Vitamin D deficiency plays key role in the pathophysiology of risk factors of metabolic syndrome which affect cardiovascular system, increase insulin resistance and obesity, stimulate rennin-angiotensin-aldosterone system that cause hypertension. The discovery of vitamin D receptor expressed ubiquitously in almost all body cells such as immune, vascular and myocardial cells, pancreatic beta cells, neurons and osteoblasts suggests an involvement of vitamin D mediated effects on metabolic syndrome. Moreover vitamin D deficiency as well as cardiovascular diseases and related risk factors frequently co-occur. This underlines the importance of understanding the role of vitamin D in the context of metabolic syndrome. The paper provides an insight into the physiology of vitamin D and relationship of vitamin D deficiency with risk factors of metabolic syndrome through observational and supplementation studies.

Racial Difference in Response to Vitamin D Supplementation

This manuscript is the result of work supported by the use of resources and facilities at the Louis Stokes Cleveland Department of Veterans Affairs Medical Center, specifically, the Geriatric Research Education and Clinical Center (GRECC).

BACKGROUND

Deficiency in 25-hydroxyvitamin D (25[OH]D) is common, especially in the elderly and African Americans (AA). While 25(OH) D deficiency is associated with multiple negative health outcomes, current recommendations for supplementation of this deficiency may be insufficient.

OBJECTIVE

To determine the prevalence of 25(OH)D deficiency, the extent of vitamin D supplementation, and the effect of supplementation on 25(OH) D levels in an elderly Veteran population. The study also focused specifically on the role of race in the risk for 25(OH)D deficiency and in the response to vitamin D supplementation.

METHODS

A retrospective chart review was conducted of information including 25(OH)D serum levels pre and post-supplementation, race, and vitamin D supplementation. Subjects were community-dwelling Veterans (≥60years) followed by a VA geriatric clinic. A total of 234 charts were reviewed (124 Caucasian, 78 AA, 32 other/unknown race). Information collected through the chart review was analyzed by comparing the means of 25(OH)D levels pre and post-supplementation across races and across times.

RESULTS

At Baseline 206 subjects (88%) were 25(OH)D deficient (<32ng/ml). While 80.6% of them were supplemented, only 10.24% (17 of 166) achieved normal 25(OH)D serum levels. AAs (n=78) had significantly lower Baseline levels compared to Caucasians (n=124) and differences were consistent across time. Fewer AAs than Caucasians increased to normal (AA:6.3%; Caucasian:12.8%).

CONCLUSIONS

Conservative oral vitamin D supplementation is largely ineffective at achieving therapeutic serum levels, especially for AAs. Future research is needed to focus on individualized supplementation strategies and targeted risk factors such as race.

Vitamin D levels predict hospitalization and mortality in patients with heart failure

OBJECTIVES

Low levels of vitamin D are closely associated with cardiovascular diseases. Heart failure (HF) is a major health problem globally, occurring with increasing frequency and characterised by poor prognosis despite therapy. We aimed to investigate the effect of vitamin D levels on hospitalisation and mortality in patients with HF.

DESIGN

Patients with ejection fraction <50% (n = 219) were included in this prospective study. Demographic, clinical and laboratory parameters were obtained at presentation. Patients were classified into Group 1 (vitamin D level ≤50 nmol/L) and Group 2 (vitamin D level >50 nmol/L). Median follow-up time was 12 months. Hospitalisation rates and overall survival were compared between groups. Independent predictors of hospitalisation and mortality were defined.

RESULTS

With a median follow-up period of 12 months, hospitalisation and overall death occurred more frequently in Group 1 than in Group 2 (23.4% vs 7.3% and 16.1% vs 1.2%, respectively; p < 0.005 for both).Vitamin D was defined as an independent predictor of hospitalisation and mortality.Higher levels were found to be associated with decreased hospitalisation (HR 0.89, 95% CI 0.84-0.95, p < 0.001) and mortality (HR 0.83, 95% CI 0.75-0.92, p < 0.001).

CONCLUSIONS

Vitamin D deficiency is highly prevalent in patients with HF, and low vitamin D levels are closely associated with increased hospitalisation and mortality.

Clinical and laboratory determinants of low serum level of 25-hydroxyvitamin D during escalation of pharmacotherapy in heart failure patients

INTRODUCTION

The activation of the renin-angiotensin-aldosterone (RAA) system is a main element of the pathophysiology of chronic heart failure (CHF), determining its symptoms and prognosis. Vitamin D is an RAA inhibitor, and its deficiency frequently accompanies CHF. The factors determining the concentration of 25-hydroxyvitamin D [25(OH)D] in CHF are not well understood, although an association has been suggested between the deficiency and the advancement of CHF. Also unknown is the influence of therapeutic escalation using recommended agents on the serum level of 25(OH)D. The aim of this study was to examine the incidence of abnormal 25(OH)D concentrations in CHF patients and to establish the clinical and laboratory determinants of low activity of this metabolite.

MATERIAL AND METHODS

The retrospective analysis included the data of 412 CHF patients not receiving optimal pharmacological treatment who were initially in NYHA (New York Heart Association) class III or IV. Over the period of 3 months the therapy was escalated until reaching maximum tolerated doses or those recommended by the current guidelines. After optimizing the therapy, the incidence of 25(OH)D deficiency (< 30 ng/ml) and insufficiency (< 20 ng/ml) was established, and clinical and laboratory determinants for these abnormal concentrations were analyzed.

RESULTS

Normal serum level, insufficiency, and deficiency of 25(OH)D were observed in, respectively, 41.5%, 26.0% and 32.5% of patients. The NYHA class improved by at least 1 class in 63.6% of patients, remained unchanged in 32.8% of patients, and deteriorated in 3.6% of patients. In multivariables analysis, low availability of natural ultraviolet B (UVB) radiation, loss of body mass during the CHF, higher concentrations of phosphates and albumins, and the presence of diabetes increased the risk of 25(OH)D deficiency, while higher concentrations of uric acid reduced this risk. In patients with a positive response to therapy, the concentration of 25(OH)D was borderline significantly higher (p = 0.055), while insufficiency and deficiency were less frequent (p = 0.02) than in patients without a treatment response, but this pertained only to patients with higher exposure to UVB. These differences were not observed in patients with low UVB exposure.

CONCLUSIONS

The concentration of 25(OH)D in CHF patients is not associated with the advancement of the disease, but is strongly determined by the potential availability of UVB radiation. A positive response to therapy increases the concentration of 25(OH)D only in the case of high UVB exposure; other determinants of 25(OH)D level include the patient's metabolic profile and the presence of diabetes.

Vitamin D deficiency plays an important role in cardiac disease and affects patient outcome: Still a myth or a fact that needs exploration?

There is increasing evidence that a low vitamin D status may be an important and hitherto neglected factor of cardiovascular disease. This review is an overview of the current body of literature, and presents evidence of the mechanisms through which vitamin D deficiency affects the cardiovascular system in general and the heart in particular. Available data indicate that the majority of congestive heart failure patients have 25-hydroxyvitamin D deficiency. Furthermore, the low serum 25-hydroxyvitamin D level has a higher impact on hypertension, coronary artery disease an on the occurrence of relevant cardiac events. A serum 25-hydroxyvitamin D level below 75 nmol/l (30 ng/l) is generally regarded as vitamin D insufficiency in both adults and children, while a level below 50 nmol/l (20 ng/l) is considered deficiency. Levels below 50 nmol/l (20 ng/l) are linked independently to cardiovascular morbidity and mortality.

Vitamin D status and Parkinson's disease: a systematic review and meta-analysis

To estimate the associations between vitamin D status and Parkinson's disease (PD). We searched electronic databases of the human literature in PubMed, EMBASE and the Cochrane Library up to February, 2014 using the following keywords: 'vitamin D' or '25(OH)D' and 'status' or 'deficiency' or 'insufficiency' and 'Parkinson's disease'. A systematic review and meta-analysis were conducted on observational studies that reported the association between blood vitamin D levels and PD. Seven studies met the inclusion criteria. 1,008 patients and 4,536 controls were included. Results of our meta-analysis show that PD patients had lower mean levels of 25-hydroxyvitamin D [25(OH)D] than healthy controls [weighted mean difference (MD), -16.9, 95 % confidence interval (CI)], -33.5 to -0.2). Patients with vitamin D insufficiency [25(OH)D level <75 nmol/l] had an increased risk of PD (OR 1.5, 95 % CI 1.1-2.0). Patients with vitamin D deficiency [25(OH)D level <50 nmol/l] experienced a twofold increased risk of PD (OR 2.2, 95 % CI 1.5-3.4). Low vitamin D levels are associated with an increased risk of PD.

Vitamin D status and the risk of multiple sclerosis: a systematic review and meta-analysis

To estimate the associations between vitamin D status and multiple sclerosis (MS). We searched electronic databases of the human literature in PubMed, EMBASE and the Cochrane Library up to February, 2014 using the following keywords: 'vitamin D' or '25(OH)D' and 'status' or 'deficiency' or 'insufficiency' and 'multiple sclerosis'. A systematic review and meta-analysis were conducted on observational studies that reported the association between blood vitamin D levels and MS. Eleven studies met the inclusion criteria. 1007 patients and 829 controls were included. Results of our meta-analysis show that MS patients had lower mean levels of 25-hydroxyvitamin D [25(OH)D] than healthy controls (weighted mean difference[MD], -14.52, 95% confidence interval [CI], -23.83 to -5.22). There were statistically significant heterogeneity (P<0.00001; I(2)=92%). The significant heterogeneity may be due to the differences in ethnicity, country, season of blood sampling and age of the participants studied. To sum up, low vitamin D levels are associated with an increased risk of MS.

Plasma vitamin D-binding protein and risk of heart failure in male physicians

Previous studies have suggested that vitamin D deficiency might contribute to the pathogenesis of heart failure (HF); however, limited data are available on the association of vitamin D-binding protein (VDBP)--a major transport protein for vitamin D--and the development of HF. Thus, we investigated whether plasma VDBP is inversely associated with HF risk. Using a prospective nested case-control design, we selected 464 cases and 464 matched controls from the Physicians' Health Study for the present analyses. VDBP was determined using an enzyme-linked immunoassay. Self-reported HF was obtained through annual follow-up questionnaires and validated in a subsample by a review of the medical records. We used conditional logistic regression analyses to compute the adjusted odds ratios. The mean age was 58.6 years, and the median VDBP was 307.8 μg/ml (interquartile range 265.2 to 354.6). Plasma VDBP was not associated with HF in our study. Across the consecutive quintiles of VDBP, the odds ratio was 1.0 (95% confidence interval [CI] reference), 1.05 (95% CI 0.66 to 1.65), 1.28 (95% CI 0.80 to 2.06), 1.07 (95% CI 0.65 to 1.75), and 1.28 (95% CI 0.76 to 2.15); p for linear trend = 0.41, after adjustment for matching factors, body mass index, diabetes, atrial fibrillation, hypertension, and high-sensitivity C-reactive protein. In conclusion, our data have shown no significant association between the plasma levels of VDBP and HF risk in apparently healthy male physicians.

Can vitamin D supplementation improve the severity of congestive heart failure?

The aim of the present study was to investigate whether vitamin D supplementation could improve biochemical findings and functional capacity of patients with heart failure (HF). One hundred patients with New York Heart Association (NYHA) class I through III HF were included in this prospective study and their 25-hydroxyvitamin D levels were evaluated. Only 6% of the participants had a sufficient serum concentration of 25(OH) D >30 nmol/L. Patients with insufficient or deficient serum levels of 25(OH) D (<30 ng/mL and <20 ng/mL, respectively) received oral vitamin D3 (cholecalciferol) for a total period of 4 months. Vitamin D supplementation increased mean serum concentration of 25(OH) D from 12.63±7.60 nmol/L to 54.49±18.01 nmol/L (P<.001). After vitamin D supplementation, the serum level of pro-brain natriuretic peptide markedly decreased (P<.001). Cholecalciferol significantly decreased high-sensitivity C-reactive protein level (P<.001). Restoration of serum 25(OH) D level was also associated with substantial improvement in NYHA class (P<.001) and 6-minute walk distance (P<.001).

25-hydroxyvitamin d and severity of Parkinson's disease

Introduction. A role for vitamin D deficiency in Parkinson's disease (PD) has recently been proposed. Given the growing body of evidence for the association of vitamin D with several neurodegenerative disorders and unavailability of any published study in the Middle East, the present study is aimed to determine the associations of circulating 25-hydroxyvitamin D (25OHD) levels with the severity of PD in an Iranian sample. Methods. In 109 patients, the severity of PD was evaluated by using Hoehn & Yahr (HR) stages and Unified Parkinson's Disease Rating Stage (UPDRS) Part III compared with 25OHD level in a double-blind and cross-sectional study. Results. Mean ± SD levels of 25OHD were 28.5 ± 1.4 and 27.1 ± 1.5, for males and females, respectively. Also, 38.4% of the patients showed deficiency levels of 25OHD (<20 ng/mL), and 72.8% had insufficient levels (<30 ng/mL). High prevalence of 25OHD insufficiency in subjects with early disease was not associated with HR stage and UPDRS scores even after multivariate adjustment for possible confounders including disease duration. Conclusions. These findings are consistent with the possibility that vitamin D status does not seem to deteriorate during the early disease stages of PD. Further studies are needed to reveal the natural role and significance of vitamin D insufficiency in PD.

Prevalence of 25(OH) vitamin D insufficiency and deficiency in pediatric patients on chronic dialysis

BACKGROUND

25(OH) Vitamin D [25(OH)D] is the major circulating form of vitamin D and the parameter used to reflect vitamin D status. Patients with chronic kidney disease (CKD) are likely to have low levels of 25(OH)D, and recent observations have linked suboptimal vitamin D status with adverse cardiovascular outcomes, inflammation, insulin resistance, and the rate of progression of renal insufficiency. Little is known about the magnitude of vitamin D deficiency in pediatric patients with stage 5 CKD on chronic dialysis.

OBJECTIVES

The aim of the present cross-sectional study was to assess the prevalence of abnormal vitamin D status in children on chronic dialysis.

METHODS

Serum 25(OH)D, 1,25(OH)2 vitamin D [1,25(OH)2D], calcium, phosphorus, and parathyroid hormone (PTH) were evaluated in 59 pediatric patients on chronic dialysis. Weekly renal Kt/V and creatinine clearance (CCr) were evaluated as parameters reflecting residual renal function. In these patients, serum 25(OH)D concentrations less than 10 ng/mL were considered deficiency and concentrations of 10 - 30 ng/mL were considered insufficiency.

RESULTS

Of the 59 pediatric patients (mean age: 14.4 ± 5.1 years), 51 (86.4%) were on peritoneal dialysis (PD), and 8 (13.6%) were on hemodialysis. Vitamin D deficiency was found in 32.2% of the patients (n = 19), and vitamin D insufficiency, in 50.8% (n = 30). Patients with serum 25(OH)D concentrations less than 30 ng/mL were older than those with normal 25(OH)D concentrations (15.4 ± 4.5 years vs 9.2 ± 5.1 years, p = 0.000). Patients with 25(OH) D concentrations less than 30 ng/mL had higher PTH levels than did those with normal 25(OH)D concentrations (349.5 ± 318.3 pg/mL vs 142.5 ± 116.9 pg/mL, p = 0.001). In the univariate analysis, there was no correlation between serum 25(OH)D and serum 1,25(OH)2D (r = 0.242, p = 0.064), calcium (r = 0.108, p = 0.415), phosphorus (r = -0.050, p = 0.706), or body mass index (r = -0.046, p = 0.729). In PD patients, serum 25(OH)D was positively correlated with weekly renal Kt/V (r = 0.385, p = 0.005) and CCr (r = 0.443, p = 0.001). In addition, serum 25(OH)D and serum albumin were positively correlated (r = 0.297, p = 0.035) in the PD patients.

CONCLUSIONS

The present study found a high prevalence of 25(OH)D deficiency and insufficiency in children on chronic dialysis. Serum 25(OH)D was associated with residual renal function in children on PD. Further studies to evaluate the consequences of vitamin D deficiency and the impact of therapeutic interventions are needed in pediatric CKD patients.

Vitamin D in exercise: physiologic and analytical concerns

Despite a wide number of studies performed on the general population, little is known about the Vitamin D status of athletes. A particular influence of many factors, including skin pigmentation, early- or late-day training, indoor training, geographic location and extensive sunscreen use, has been observed in this specific population. The need of supplementation with Vitamin D in athletes is not defined or, when supplementation is needed, even the optimal amount of Vitamin D to be used is not specified. The periodic measurement of Vitamin D is the only procedure capable to define athletes' status. Although various methods for the measurement of Vitamin D are routinely used, they often give discordant and poorly reproducible results; thus, it is necessary to standardize the various methods, in order to have comparable results. In conclusion, current available data indicate both that little is known about the Vitamin D status of athletes and that is still unclear if supplementation could be desirable. Finally, it must be pointed out that all the papers about Vitamin D status should indicate in detail the method used for really allowing a correct interpretation of data.

The role of vitamin D in pregnancy and lactation: emerging concepts

Pregnancy is a critical time in the lifecycle of a woman where she is responsible not only for her own well-being, but also that of her developing fetus, a process that continues during lactation. Until recently, the impact of vitamin D status during this period had not been fully appreciated. Data regarding the importance of vitamin D in health have emerged to challenge traditional dogma, and suggest that vitamin D - through its effect on immune function and surveillance - plays a role beyond calcium and bone metabolism on the health status of both the mother and her fetus. Following birth, this process persists; the lactating mother continues to be the main source of vitamin D for her infant. Thus, during both pregnancy and lactation, maternal deficiency predicts fetal and infant deficiency; the significance of this is just beginning to be understood and will be highlighted in this review.

Vitamin D deficiency exacerbates experimental stroke injury and dysregulates ischemia-induced inflammation in adult rats

Vitamin D deficiency (VDD) is widespread and considered a risk factor for cardiovascular disease and stroke. Low vitamin D levels are predictive for stroke and more fatal strokes in humans, whereas vitamin D supplements are associated with decreased risk of all-cause mortality. Because VDD occurs with other comorbid conditions that are also independent risk factors for stroke, this study examined the specific effect of VDD on stroke severity in rats. Adult female rats were fed control or VDD diet for 8 wk and were subject to middle cerebral artery occlusion thereafter. The VDD diet reduced circulating vitamin D levels to one fifth (22%) of that observed in rats fed control chow. Cortical and striatal infarct volumes in animals fed VDD diet were significantly larger, and sensorimotor behavioral testing indicated that VDD animals had more severe poststroke behavioral impairment than controls. VDD animals were also found to have significantly lower levels of the neuroprotective hormone IGF-I in plasma and the ischemic hemisphere. Cytokine analysis indicated that VDD significantly reduced IL-1α, IL-1β, IL-2, IL-4, IFN-γ, and IL-10 expression in ischemic brain tissue. However, ischemia-induced IL-6 up-regulation was significantly higher in VDD animals. In a separate experiment, the therapeutic potential of acute vitamin D treatments was evaluated, where animals received vitamin D injections 4 h after stroke and every 24 h thereafter. Acute vitamin D treatment did not improve infarct volume or behavioral performance. Our data indicate that VDD exacerbates stroke severity, involving both a dysregulation of the inflammatory response as well as suppression of known neuroprotectants such as IGF-I.

Vitamin D and its role during pregnancy in attaining optimal health of mother and fetus

Despite its discovery a hundred years ago, vitamin D has emerged as one of the most controversial nutrients and prohormones of the 21st century. Its role in calcium metabolism and bone health is undisputed but its role in immune function and long-term health is debated. There are clear indicators from in vitro and animal in vivo studies that point to vitamin D's indisputable role in both innate and adaptive immunity; however, the translation of these findings to clinical practice, including the care of the pregnant woman, has not occurred. Until recently, there has been a paucity of data from randomized controlled trials to establish clear cut beneficial effects of vitamin D supplementation during pregnancy. An overview of vitamin metabolism, states of deficiency, and the results of recent clinical trials conducted in the U.S. are presented with an emphasis on what is known and what questions remain to be answered.

Association of 25-hydroxyvitamin D deficiency with NT-pro BNP levels in patients with acute myocardial infarction: a cross-sectional analysis

Background

Nutritional vitamin D deficiency is an emerging risk factor for acute myocardial infarction (AMI) and heart failure. The association of 25-hydroxyvitamin D levels with N-terminal pro B-type natriuretic peptide (NT-proBNP), a robust prognostic marker for post-AMI mortality and heart failure, is unknown and could illuminate a potential pathway for adverse outcomes among post-AMI patients with 25-hydroxyvitamin D deficiency.

Methods

In a cross-sectional analysis, we studied 238 AMI patients from 21 U.S. centers to test the association of nutritional vitamin D (25-hydroxyvitamin D [25(OH)D]) deficiency with NT-proBNP levels. Levels of 25(OH)D levels were categorized as normal (≥30 ng/mL), insufficient (>20 - <30 ng/mL), deficient (>10 - ≤20 ng/mL), or severely deficient (≤10 ng/mL).

Results

Low 25(OH)D levels were found in 95.7% of AMI patients. No significant trends for higher mean baseline log NT-proBNP levels in severely deficient (6.9 ± 1.3 pg/mL), deficient (6.9 ± 1.2 pg/mL), and insufficient (6.9 ± 0.9 pg/ml) groups were observed as compared with patients having normal (6.1 ± 1.7 pg/mL) levels, P = 0.17. Findings were similar in the subset of patients who had follow-up NT-proBNP levels drawn at one month. In multivariate regression modeling, after adjusting for multiple covariates, 25(OH)D was not associated with NT-proBNP.

Conclusions

Potential associations between nutritional vitamin D deficiency and prognosis in the setting of AMI are unlikely to be mediated through NT-proBNP pathways. Future studies should examine other mechanisms, such as inflammation and vascular calcification, by which 25(OH)D deficiency could mediate adverse outcomes post-AMI.

Vitamin d and stage 5 chronic kidney disease: a new paradigm?

Vitamin D receptor agonists (VDRA) are currently recommended for the treatment of secondary hyperparathyroidism in stage 5 CKD. They are considered to be contraindicated in the presence of low or normal (for a dialysis patient) levels of PTH due to the risk of developing adynamic bone disease, with consequent vascular calcification. However, these recommendations are increasingly at odds with the epidemiological evidence, which consistently shows a large survival advantage for patients treated with low-dose VDRAs, regardless of plasma calcium, phosphate, or PTH. A large number of pleiotropic effects of vitamin D have been described, including inhibition of renin activity, anti-inflammation, and suppression of vascular calcification stimulators and stimulation of vascular calcification inhibitors present in the uremic milieu. Laboratory studies suggest that a normal cellular vitamin D level is necessary for normal cardiomyocyte and vascular smooth muscle function. While pharmacological doses of VDRA can be harmful, the present evidence suggests that the level of 1,25-dihydroxycholecalciferol should also be more physiological in stage 5 CKD, and that widespread use of low-dose VDRA would be beneficial. A randomized controlled trial to test this hypothesis is warranted.

Vitamin D supplementation during pregnancy: double-blind, randomized clinical trial of safety and effectiveness

The need, safety, and effectiveness of vitamin D supplementation during pregnancy remain controversial. In this randomized, controlled trial, women with a singleton pregnancy at 12 to 16 weeks' gestation received 400, 2000, or 4000 IU of vitamin D(3) per day until delivery. The primary outcome was maternal/neonatal circulating 25-hydroxyvitamin D [25(OH)D] concentration at delivery, with secondary outcomes of a 25(OH)D concentration of 80 nmol/L or greater achieved and the 25(OH)D concentration required to achieve maximal 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] production. Of the 494 women enrolled, 350 women continued until delivery: Mean 25(OH)D concentrations by group at delivery and 1 month before delivery were significantly different (p < 0.0001), and the percent who achieved sufficiency was significantly different by group, greatest in 4000-IU group (p < 0.0001). The relative risk (RR) for achieving a concentration of 80 nmol/L or greater within 1 month of delivery was significantly different between the 2000- and the 400-IU groups (RR = 1.52, 95% CI 1.24-1.86), the 4000- and the 400-IU groups (RR = 1.60, 95% CI 1.32-1.95) but not between the 4000- and. 2000-IU groups (RR = 1.06, 95% CI 0.93-1.19). Circulating 25(OH)D had a direct influence on circulating 1,25(OH)(2)D(3) concentrations throughout pregnancy (p < 0.0001), with maximal production of 1,25(OH)(2)D(3) in all strata in the 4000-IU group. There were no differences between groups on any safety measure. Not a single adverse event was attributed to vitamin D supplementation or circulating 25(OH)D levels. It is concluded that vitamin D supplementation of 4000 IU/d for pregnant women is safe and most effective in achieving sufficiency in all women and their neonates regardless of race, whereas the current estimated average requirement is comparatively ineffective at achieving adequate circulating 25(OH)D concentrations, especially in African Americans.

Parameters of mineral metabolism predict midterm clinical outcome in end-stage heart failure patients

OBJECTIVES

We investigated to which extent disturbances in mineral metabolism predict 90-day clinical outcome in end-stage heart failure patients.

DESIGN

Among numerous biochemical parameters, we measured serum levels of sodium and magnesium, the calciotropic hormones parathyroid hormone and 1,25-dihydroxyvitamin D as well as fibroblast growth factor-23 (a phosphaturic hormone) in 305 cardiac transplant candidates. Primary endpoint was a composite of the need of mechanical circulatory support (MCS), transplantation, or death.

RESULTS

Of the study cohort, 33.4% reached the primary endpoint. In detail, 19% were transplanted (the vast majority was listed "high urgent"), 8.8% died and 5.6% received MCS implants. As determined by logistic regression analysis, all aforementioned biochemical parameters were independently related to the primary endpoint. Results did not change substantially when transplanted patients were censored. A risk score (0-5 points) was developed. Of the patients who scored 5 points 89.5% reached the primary endpoint whereas of the patients with a zero score only 3.8% reached the primary endpoint.

CONCLUSIONS

Our data demonstrate that in addition to the well-known predictive value of disturbed sodium metabolism, derangements in calcium, phosphate, and magnesium metabolism also predict midterm clinical outcome in end-stage heart failure patients.

Management of heart failure with renal artery ischemia

With improved treatment, patients are surviving longer with impaired ventricular function. Hypertension results in ventricular remodeling in many patients. More than 5 million people have heart failure and are likely to have one or more co-existent diseases associated with aging, one of which is chronic kidney disease (CKD). Renal artery stenosis is fraught with varying opinions. Nephrologists, cardiologists, and interventional radiologists all manage these diseases with different strategies. This article outlines renovascular disease as it relates to CKD, the pathophysiology of development of renovascular disease and effects leading to congestive heart failure, treatment modalities, and outcomes of treatment regimens.

Vitamin D deficiency in patients with congestive heart failure: mechanisms, manifestations, and management

Recent research suggests that vitamin D may play a role in cardiovascular (CV) health. Although its exact role is still debated and is a matter of controversy, vitamin D deficiency has been linked to increased prevalence of CV risk factors and events. Factors that predispose persons with congestive heart failure (CHF) to hypovitaminosis D include nutritional deficiency, decreased skin production, reduced intestinal absorption, and hepatorenal disease. It is possible that low vitamin D can in turn aggravate CHF. The extent of deficiency can be severe enough to cause hypocalcemia, secondary hyperparathyroidism, osteomalacia, and decreased bone density. No clear data exist showing improvement in CV clinical outcomes with vitamin D replacement. Screening is advocated in most patients, although benefits of replacement are most likely to accrue in those with severe lack or with abnormalities of calcium-parathyroid-bone metabolism. According to current guidelines and research, vitamin D goals of >20 ng/ml in most patients with CHF and >30 ng/ml in those with secondary hyperparathyroidism seem to be appropriate to aim for. Further research is needed to fully unravel the association among CV risk, CHF and hypovitaminosis D, and translate this knowledge into clinically meaningful management recommendations.

Vitamin D deficiency is an independent predictor of anemia in end-stage heart failure

Both, anemia and vitamin D deficiency are prevalent in patients with heart failure. According to recent evidence, vitamin D may stimulate erythropoiesis. We measured circulating 25-hydroxyvitamin D (25[OH]D), 1,25-dihydroxyvitamin D (1,25[OH](2)D) and hemoglobin (Hb) in a cross-sectional study in 364 end-stage heart failure patients awaiting cardiac transplantation, of whom 52.6% met the criteria for anemia (Hb < 13 g/dl in males and <12 g/dl in females). None of the patients were on erythrocyte-stimulating agents. Of the study cohort, 87.8% had 25(OH)D concentrations below 50 nmol/l. The mean Hb concentrations were significantly reduced in the lower tertiles of 25(OH)D and 1,25(OH)(2)D (P < 0.001). In multivariate-adjusted logistic regression analyses, the odds ratios for anemia of the lowest tertile of 25(OH)D (<18 nmol/l) and 1,25(OH)(2)D (<40 pmol/l) were 2.69 (1.46-5.00) and 4.08 (2.18-7.62) compared with their respective highest tertile (>32 nmol/l and >70 pmol/l). Patients with severe dual deficiency of 25(OH)D and 1,25(OH)(2)D had an odds ratio for anemia of 9.87 (95% CI 3.59-27.1) compared with patients in the highest tertile for both vitamin D metabolites. Circulating 1,25(OH)(2)D was directly related to circulating 25(OH)D levels and kidney function (P < 0.001), and inversely associated with C-reactive protein (P = 0.020). Our data demonstrate that vitamin D deficiency is independently associated with low Hb values and anemia in end-stage heart failure. Circulating 1,25(OH)(2)D is a better predictor of anemia than circulating 25(OH)D. Prospective randomized studies with administration of vitamin D (metabolites) will have to clarify if the association of vitamin D deficiency with anemia is causal.

Congestive heart failure: where homeostasis begets dyshomeostasis

Despite today's standard of care, aimed at preventing homeostatic neurohormonal activation, one in every five patients recently hospitalized with congestive heart failure (CHF) will be readmitted within 30 days of discharge because of a recurrence of their symptoms and signs. In light of recent pathophysiological insights, it is now propitious to revisit CHF with a view toward complementary and evolving management strategies. CHF is a progressive systemic illness. Its features include: oxidative stress in diverse tissues; an immunostimulatory state with circulating proinflammatory cytokines; a wasting of soft tissues; and a resorption of bone. Its origins are rooted in homeostatic mechanisms gone awry to beget dyshomeostasis. For example, marked excretory losses of Ca2+ and Mg2+ accompany renin-angiotensin-aldosterone system activation, causing ionized hypocalcemia and hypomagnesemia that lead to secondary hyperparathyroidism with consequent bone resorption and a propensity to atraumatic fractures. Parathyroid hormone accounts for paradoxical intracellular Ca2+ overloading in diverse tissues and consequent systemic induction of oxidative stress. In cardiac myocytes and mitochondria, these events orchestrate opening of the mitochondrial permeability transition pore with an ensuing osmotic-based destruction of these organelles and resultant cardiomyocyte necrosis with myocardial scarring. Contemporaneous with Ca2+ and Mg2+ dyshomeostasis is hypozincemia and hyposelenemia, which compromise metalloenzyme-based antioxidant defenses, whereas hypovitaminosis D threatens Ca2+ stores needed to prevent secondary hyperparathyroidism. An intrinsically coupled dyshomeostasis of intracellular Ca2+ and Zn2+, representing pro-oxidant and antioxidant, respectively, is integral to regulating the mitochondrial redox state; it can be uncoupled by a Zn2+ supplement in favor of antioxidant defenses. Hence, the complementary use of nutriceuticals to nullify dyshomeostatic responses involving macro- and micronutrients should be considered. Evolving strategies with mitochondria-targeted interventions interfering with their uptake of Ca2+ or serving as selective antioxidant or mitochondrial permeability transition pore inhibitor may also prove efficacious in the overall management of CHF.

The characteristics of stress cardiomyopathy in an ethnically heterogeneous population

OBJECTIVES

Stress cardiomyopathy is a cardiac syndrome that is characterized by transient left ventricular systolic dysfunction in the absence of obstructive coronary artery disease. Its epidemiology has been described in homogeneous Asian, Caucasian and Black populations, but its characteristics in heterogeneous populations are poorly understood. Our aim was to assess the characteristics of stress cardiomyopathy in a heterogeneous population that included a large percentage of Hispanics.

METHODS

We reviewed 59 consecutive cases of stress cardiomyopathy that were confirmed by coronary angiography and were in agreement with the Mayo Clinic diagnostic criteria.

RESULTS

The mean age of the patients was 74 years (range, 39-91 years), and 37 patients were female (62.7%). Twenty-nine patients (49.2%) were Latino/Hispanic, 26 (44%) were Caucasian, 3 (5%) were Asian, and 1 patient (1.7%) was Black. The most common chief symptom was dyspnea, followed by chest pain and an absence of symptoms in 54.2, 28.8, and 18.6% of the patients, respectively. The primary EKG abnormalities consisted of a T wave inversion, an ST segment elevation, and ST segment depression in 69.5%, 25.4%, and 15.3% of the patients, respectively. The stressor event was identified in 90% of the cases. In 32 cases (54%), the stressor event was physical stress or a medical illness, and in 21 cases (35.6%), the stressor event was emotional stress. The in-hospital mortality rate was 8.5%.

CONCLUSIONS

In our heterogeneous study population, stress cardiomyopathy presented with a 3:2 female-to-male ratio, and dyspnea was the most common chief complaint. Stress cardiomyopathy exhibited a T wave inversion as the primary EKG abnormality. These findings differ from previous cases that have been reported, and further studies are needed.

Vitamin D deficiency and myocardial diseases

Vitamin D deficiency is common among patients with myocardial diseases because sun-induced vitamin D production in the skin and dietary intake of vitamin D is often insufficient. Knockout mice for the vitamin D receptor develop myocardial hypertrophy and dysfunction. It has also been shown that children with rickets who suffered from severe heart failure could be successfully treated with supplementation of vitamin D plus calcium. In adults, almost all patients with heart failure exhibit reduced 25-hydroxyvitamin D levels, which are used to classify the vitamin D status. In prospective studies, vitamin D deficiency was an independent risk factor for mortality, deaths due to heart failure and sudden cardiac death. Several vitamin D effects on the electrophysiology, contractility, and structure of the heart suggest that vitamin D deficiency might be a causal factor for myocardial diseases. Data from interventional trials, however, are rare and urgently needed to elucidate whether vitamin D supplementation is useful for the treatment of myocardial diseases. In our opinion, the current knowledge of the beneficial effects of vitamin D on myocardial and overall health strongly argue for vitamin D supplementation in all vitamin D-deficient patients with or at high risk for myocardial diseases.