Vitamin D in heart failure

Vitamin D and heart failure risk among individuals with type 2 diabetes: observational and Mendelian randomization studies

BACKGROUND

Evidence is limited and inconsistent regarding vitamin D and heart failure (HF) risk in people with type 2 diabetes (T2D), among whom vitamin D insufficiency or deficiency is common.

OBJECTIVES

This study aimed to investigate the associations of serum 25-hydroxyvitamin D [25(OH)D] with HF risk among individuals with T2D, in observational and Mendelian randomization (MR) frameworks.

METHODS

Observational analyses were performed among 15,226 T2D participants aged 40-72 y from the UK Biobank. HF incidence was ascertained through electronic health records. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between serum 25(OH)D and HF risk among people with T2D. MR analyses were conducted among 11,260 unrelated participants with T2D. A weighted genetic risk score for genetically predicted 25(OH)D concentration was instrumented using 62 confirmed genome-wide variants.

RESULTS

The mean ± standard deviation of serum 25(OH)D was 43.4 ± 20.4 nmol/L. During a median follow-up of 11.3 y, 836 incident HF events occurred. Serum 25(OH)D was nonlinearly and inversely associated with HF and the decreasing risk tended to plateau at around 50 nmol/L. Comparing those with 25(OH)D <25 nmol/L, the multivariable-adjusted HR (95% CI) was 0.67 (0.54, 0.83) for participants with 25(OH)D of 50.0-74.9 nmol/L and was 0.71 (0.52, 0.98) for 25(OH)D >75 nmol/L. In MR analysis, each 7% increment in genetically predicted 25(OH)D was associated with 36% lower risk of HF among people with T2D (HR: 0.64, 95% CI: 0.41, 0.99).

CONCLUSIONS

Higher serum 25(OH)D was associated with lower HF risk among individuals with T2D and the MR analysis suggested a potential causal relationship. These findings indicate a role of maintaining adequate vitamin D status in the prevention of HF among individuals with T2D.

Evaluation of the Relationship Between Vitamin D Deficiency and Subclinical Cardiac Dysfunction Using 2D/3D Strain Echocardiography in Healthy People

AIM

Vitamin D deficiency has a high prevalence in the population and is highly associated with cardiovascular diseases. The aim of this study was to evaluate subclinical left ventricular (LV) function using strain analysis in healthy individuals with vitamin D deficiency.

MATERIAL AND METHODS

113 healthy volunteers were enrolled in the study (age, 44.1±7 yrs, 34 male). All volunteers underwent two-dimensional (2D) and three-dimensional (3D) speckle tracking echocardiography after conventional echocardiographic evaluation. The subjects were divided into two groups according to their vitamin D concentrations. 61 subjects with vitamin D less than 20 ng / ml were included in the vitamin D deficiency group. The baseline clinical characteristics, laboratory measurements, echocardiographic data, including 2D and 3D global longitudinal strain (GLS) values, were compared between the groups.

RESULTS

The 2D GLS values of the subjects with vitamin D deficiency were lower (mathematically less negative) than subjects with normal vitamin D (-16.1±3.4 vs -19.3±4.2, p<0.001). Similarly, the 3D GLS results were lower in subjects with vitamin D deficiency (-18.3±5.2 vs -24.1±6.9, p<0.001). A significant correlation was detected between the vitamin D concentrations and the 2D and 3D GLS measurements. (r=0.765 and r=0.628, respectively, p<0.001). Vitamin D was found to be an independent predictor of impaired 2D and 3D LV GLS (p=0.031, p=0.023, respectively).

CONCLUSION

Subclinical LV dysfunction in healthy individuals with vitamin D deficiency was demonstrated by 3D and 2D strain analysis. Due to potential negative effects of vitamin D deficiency on cardiac function, more attention should be paid to healthy individuals with vitamin D deficiency.

Total 25-Hydroxyvitamin D Is an Independent Marker of Left Ventricular Ejection Fraction in Heart Failure with Reduced and Mildly Reduced Ejection Fraction

Vitamin D emerged as an important prognostic biomarker in heart failure (HF), with currently highly debated therapeutic implications. Several trials on vitamin D supplementation in HF showed improvements in left ventricular (LV) remodeling and function and health-related quality of life (HRQoL), which did not translate into mid- to long-term beneficial effects regarding physical performance and mortality. We addressed total 25-hydroxyvitamin D (25(OH)D), serum albumin, and uric acid (UA) levels, focusing mainly on vitamin D deficiency, as potential markers of LV systolic dysfunction in HF with reduced and mildly reduced ejection fraction (HFrEF, HFmrEF). Seventy patients with LVEF < 50% were comprehensively evaluated using ECG, echocardiography, lung ultrasound (LUS), blood sampling, and the six-minute walk test (6MWT). HRQoL was also assessed using the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Statistically significant positive correlations were found between LVEF, 25(OH)D, serum UA, and albumin, respectively (p = 0.008, p = 0.009, and p = 0.001). Serum UA (7.4 ± 2.4 vs. 5.7 ± 2.1, p = 0.005), NT-proBNP levels (1090.4 (675.2-2664.9) vs. 759.0 (260.3-1474.8), p = 0.034), and MLHFQ scores (21.0 (14.0-47.0) vs. 14.5 (4.5-25.5), p = 0.012) were significantly higher, whereas 25(OH)D concentrations (17.6 (15.1-28.2) vs. 22.7 (19.5-33.8), p = 0.010) were lower in subjects with severely reduced LVEF. Also, 25(OH)D was independently associated with LVEF in univariate and multiple regression analysis, maintaining its significance even after adjusting for confounders such as age, NT-proBNP, the presence of chronic coronary syndrome, hypertension, and anemia. According to our current findings, 25(OH)D is closely associated with LVEF, further supporting the need to establish correct vitamin D supplementation schemes and dietary interventions in HF. The changes in LVEF, 25(OH)D, serum UA, and albumin levels in HFrEF and HFmrEF indicate a similar pathophysiological background.

Is Hypovitaminosis D a Risk Factor for Heart Failure?

BACKGROUND

Several studies in recent years have shown the association between vitamin D levels and heart failure. Vitamin D deficiency is related to increased cardiovascular morbidity and mortality, with a higher risk of developing heart failure. In this systematic review, we aimed to assess recent studies that analyzed vitamin D deficiency and heart failure in adult and pediatric populations. (2) Methods: We conducted a systematic search for studies published in the following databases: PubMed and Scopus from January 2012 to October 2022. (3) Results: Most observational studies that were included found a significant association between hypovitaminosis D and heart failure. However, the beneficial role of vitamin D supplementation is still controversial due to the lack of randomized controlled trials. (4) Conclusions: Vitamin D may play an important role as a cardiovascular marker in heart failure patients. More well-designed studies are needed to investigate the relationship between vitamin D and heart failure and to determine if vitamin D supplementation could improve long-term outcomes.

A pathway phenotype linking metabolic, immune, oxidative, and opioid pathways with comorbid depression, atherosclerosis, and unstable angina

BACKGROUND

There is strong comorbidity between atherosclerosis (ATS) and depression which is attributed to increased atherogenicity, insulin resistance (IR), and immune and oxidative stress.

AIM OF THE STUDY

To examine the role of the above pathways and mu-opioid receptor (MOR), β-endorphin levels, zinc, copper, vitamin D3, calcium, and magnesium in depression due to ATS/unstable angina (UA).

METHODS

Biomarkers were assayed in 58 controls and 120 ATS patients divided into those with moderate and severe depression according to the Beck Depression Inventory-II (BDI-II) scores >19 and >29, respectively.

RESULTS

Neural network and logistic regression models showed that severe depression due to ATS/UA was best predicted by interleukin-6 (IL-6), UA, MOR, zinc, β-endorphin, calcium and magnesium, and that moderate depression was associated with IL-6, zinc, MOR, β-endorphin, UA, atherogenicity, IR, and calcium. Neural networks yielded a significant discrimination of severe and moderate depression with an area under the receiver operating curves of 0.831 and 0.931, respectively. Using Partial Least Squares path analysis, we found that 66.2% of the variance in a latent vector extracted from ATS/UA clinical features, and the BDI-II scores, atherogenicity, and IR could be explained by the regression on IL-6, IL-10, zinc, copper, calcium, MOR, and age. The BDI-II scores increased from controls to ATS to UA class III to UA class IV.

CONCLUSIONS

Immune activation, the endogenous opioid system, antioxidants, trace elements, and macrominerals modulate a common core shared by increased depressive symptoms, ATS, UA, atherogenicity, and IR.

Fibroblast Growth Factor 23 and Risk of New Onset Heart Failure With Preserved or Reduced Ejection Fraction: The PREVEND Study

Background

The role of fibroblast growth factor 23 (FGF23) in the development of new‐onset heart failure (HF) with reduced (HFrEF) or preserved ejection fraction (HFpEF) in the general population is unknown. Therefore, we set out to investigate associations of C‐terminal FGF23 with development of new‐onset HF and, more specifically, with HFrEF or HFpEF in a large, prospective, population‐based cohort.

Methods and Results

We studied 6830 participants (aged 53.8±12.1 years; 49.7% men; estimated glomerular filtration rate, 93.1±15.7 mL/min per 1.73 m²) in the community‐based PREVEND (Prevention of Renal and Vascular End‐Stage Disease) study who were free of HF at baseline. Cross‐sectional multivariable linear regression analysis showed that ferritin (standardized β, −0.24; P<0.001) and estimated glomerular filtration rate (standardized β, −0.13; P<0.001) were the strongest independent correlates of FGF23. Multivariable Cox proportional hazard regression was used to study the association between baseline FGF23 and incident HF, HFrEF (ejection fraction ≤40%) or HFpEF (ejection fraction ≥50%). After median follow‐up of 7.4 [IQR 6.9–7.9] years, 227 individuals (3.3%) developed new‐onset HF, of whom 132 had HFrEF and 88 had HFpEF. A higher FGF23 level was associated with an increased risk of incident HF (fully adjusted hazard ratio, 1.29 [95% CI, 1.06–1.57]) and with an increased risk of incident HFrEF (fully adjusted hazard ratio, 1.31 [95% CI, 1.01–1.69]). The association between FGF23 and incident HFpEF lost statistical significance after multivariable adjustment (hazard ratio, 1.22 [95% CI, 0.87–1.71]).

Conclusions

Higher FGF23 is independently associated with new‐onset HFrEF in analyses fully adjusted for cardiovascular risk factors and other potential confounders. The association between FGF23 and incident HFpEF lost statistical significance upon multivariable adjustment.

Vitamin D Deficiency in Testicular Cancer Survivors: A Systematic Review

Testicular cancer (TC) is the most frequent tumor in young males. In the vast majority of cases, it is a curable disease; therefore, very often patients experience a long survival, also due to their young age at diagnosis. In the last decades, the role of the vitamin D deficiency related to orchiectomy has become an increasingly debated topic. Indeed, vitamin D is essential in bone metabolism and many other metabolic pathways, so its deficiency could lead to various metabolic disorders especially in long-term TC survivors. In our article, we report data from studies that evaluated the incidence of hypovitaminosis D in TC survivors compared with cohorts of healthy peers and we discuss molecular mechanisms and clinical implications.

Beneficial effects of paricalcitol on cardiac dysfunction and remodelling in a model of established heart failure

BACKGROUND AND PURPOSE

The synthetic vitamin D3 analogue paricalcitol acts as a selective activator of the vitamin D receptor (VDR). While there is evidence for cardioprotective effects of paricalcitol associated with the VDR pathway, less information is available about the structural and functional cardiac effects of paricalcitol on established heart failure (HF) and particularly its effects on associated electrophysiological or Ca²⁺ handling remodelling.

EXPERIMENTAL APPROACH

We used a murine model of transverse aortic constriction (TAC) to study the effect of paricalcitol on established HF. Treatment was initiated 4 weeks after surgery over five consecutive weeks, and mice were sacrificed 9 weeks after surgery. Cardiac MRI (CMRI) was performed 4 and 9 weeks after surgery. Hearts were used for biochemical and histological studies and to isolate ventricular myocytes for electrophysiological and calcium imaging studies.

KEY RESULTS

CMRI analysis revealed that, compared with vehicle, paricalcitol treatment prevented the progression of ventricular dilation and hypertrophy after TAC and halted the corresponding decline in ejection fraction. These beneficial effects were related to the attenuation of intracellular Ca²⁺ mishandling remodelling, antifibrotic and antihypertrophic effects and potentially antiarrhythmic effects by preventing the reduction of K⁺ current density and the long QT, JT and TpTe intervals observed in HF animals.

CONCLUSION AND IMPLICATIONS

The results suggest that paricalcitol treatment in established HF hampers disease progression and improves adverse electrophysiological and Ca²⁺ handling remodelling, attenuating the vulnerability to HF-associated ventricular arrhythmias. Paricalcitol may emerge as a potential therapeutic option in the treatment of HF.

Nontraditional Cardiovascular Biomarkers and Risk Factors: Rationale and Future Perspectives

The primary prevention of cardiovascular (CV) disease depends on the capacity to identify subjects at higher risk long before the occurrence of CV clinical manifestations. Traditional risk factors do not cover fully prediction of individual risk. Moreover, there is an area of gray for patients at intermediate CV risk, which offers wide margins of improvement. These observations highlight the need for new additive tools for a more accurate risk stratification. An increasing number of candidate biomarkers have been identified to predict CV risk and events, although they generally give only a moderate increase when added to currently available predictive scores. The approach utilizing a relative small number of biomarkers in multiple combinations, but only weakly related to each other or unrelated, thus belonging to independent-pathways, and so able to catch the multidimensional characteristic of atherosclerosis, appears promising. We discuss vitamin D and bone turnover biomarkers, hepatitis C virus, and psycho-emotional factors that may reflect alternative pathways over those generally considered for atherosclerosis (e.g., aspects directly related to inflammation and thrombosis). These new biomarkers could facilitate a more accurate assessment of CV risk stratification if incorporated in the current risk assessment algorithms.

The association between the serum level of vitamin D and ischemic heart disease: a study from Jordan

Background

Decreased levels of vitamin D were associated with increased risk of multiple diseases, including cardiovascular diseases. However, there seem to be some discrepancies among the results obtained from different studies. The aim of the present study was to explore the importance of having sufficient serum levels of vitamin D in reducing the incidence and the progression of coronary artery stenosis and ischemic heart disease (IHD).

Methods

Serum levels of vitamin D were measured using radioimmunoassay in 186 Jordanian patients who underwent investigative coronary catheterization. Of these patients, 133 were suffering from coronary artery stenosis. The association between vitamin D levels, coronary stenosis and many risk factors was determined using SPSS software.

Results and conclusions

Interestingly, the current results did not show an association between vitamin D abnormalities and the incidence or the reoccurrence of coronary artery stenosis. Moreover, significant differences were detected in the prevalence of vitamin D abnormalities based on the patient’s gender, and there was a significant association between vitamin D abnormalities and both body mass index and dyslipidemia. However, current results did not show any significant association with other risk factors for IHD. For instance, no association was found with smoking, hypertension, diabetes mellitus, stable and unstable angina or with acute recent myocardial infarction.

Long term deficiency of vitamin D in germ cell testicular cancer survivors

Background

Cisplatin-based chemotherapy significantly improved the survival of patients with germ cell testicular cancer. However, long term side effects of chemotherapy have non-negligible impact on the quality of life of these young patients, who have a long life expectancy after being successfully treated.

Materials and Methods

25-OH vitamin D, testosterone, FSH and LH of patients with testicular cancer were retrospectively evaluated and for each patient clinical information were collected. The tissue of 52 patients with germ cell tumors was analyzed for VDR expression by immunohistochemistry. The serum 25-OH vitamin D and VDR expression were correlated to the patients 'clinical characteristics.

Results

25-OH vitamin D was analyzed in 82 patients. Insufficient (< 30 ng/ml) levels were detected in 65%-85%, mild deficient (< 20 ng/ml) in 25%-36% and severe deficient (< 10 ng/ml) in 6%-18% of the patients over a median follow-up of 48 months. No difference in serum 25-OH vitamin D was detected over the follow-up time points. No correlation with histology, stage and type of treatment was found. The 25-OH vitamin D levels were not correlated to testosterone, FSH and LH levels. Interestingly, the expression of VDR was much higher in non seminoma than in seminoma tissue.

Conclusions

Patients with testicular cancer have reduced vitamin D levels after the treatment of the primary cancer. Since long term hypovitaminosis D leads to high risk of fractures, infertility and cardiovascular diseases, we envision that vitamin D should be regularly checked in patients with testicular cancer and replaced if needed.

Vitamin D and its effects on cardiovascular diseases: a comprehensive review

Vitamin D is a molecule that is actively involved in multiple metabolic pathways. It is mostly known for its implications related to calcium metabolism. It has also been determined that it actively participates in the cardiovascular system, influencing blood pressure, coronary artery disease and other vascular diseases, such as heart failure and atrial fibrillation. Furthermore, it has been established that this vitamin is extensively involved in the regulation of both the renin angiotensin aldosterone system and the immune system. In this review, we present the different vitamin D metabolic pathways associated with the cardiovascular pathophysiology, and we include studies in animal and human models, as well as some of the controversies found in the literature. This review also incorporates an overview of the implications in the molecular biology and public health fields.

Short-term Variability of Vitamin D-Related Biomarkers

BACKGROUND

Quantifying the variability of biomarkers is important, as high within-person variability can lead to misclassification of individuals. Short-term variability of important markers of vitamin D metabolism is relatively unknown.

METHODS

A repeatability study was conducted in 160 Atherosclerosis Risk in Communities study participants (60% female, 28% black, mean age 76 years). Fasting serum was drawn at 2 time points, a median of 6 (range 3-13) weeks apart. Vitamin D binding protein (VDBP) and 25-hydroxyvitamin D [25(OH)D] were measured by LC-MS, fibroblast growth factor (FGF23) and parathyroid hormone (PTH) by enzyme-linked immunoassay, and calcium and phosphorus by Roche Cobas 6000. Free and bioavailable 25(OH)D were calculated. We calculated the within-person CV (CV_W), intraclass correlation coefficient (ICC), Spearman rank correlation coefficient (r), and percent reclassified.

RESULTS

The CV_W was lowest for calcium (2.0%), albumin (3.6%), 25(OH)D (6.9%), VDBP (7.0%) and phosphorus (7.6%); intermediate for free 25(OH)D (9.0%) and bioavailable 25(OH)D (9.9%); and highest for PTH (16.7%) and FGF23 (17.8%). Reclassification was highest for PTH, VDBP, and phosphorus (all 7.5%). The ICC and r were highest (≥0.80) for 25(OH)D, free 25(OH)D, bioavailable 25(OH)D and PTH, but somewhat lower (approximately 0.60-0.75) for the other biomarkers.

CONCLUSIONS

Six-week short-term variability, as assessed by CV_W, was quite low for VDBP, calcium and phosphorus, but fairly high for FGF23 and PTH. As such, multiple measurements of FGF23 and PTH may be needed to minimize misclassification. These results provide insight into the extent of potential misclassification of vitamin D markers in research and clinical settings.

Serum NT-proBNP Levels Are Not Related to Vitamin D Status in Young Patients with Congenital Heart Defects

CONTEXT

Hypovitaminosis D frequently occurs in early life and increases with age. Vitamin D has been suggested to influence cardiac performance and N-terminal-pro-type B natriuretic peptide (NT-proBNP) release in adults with heart failure.

OBJECTIVES

To assess the vitamin D status and the impact of hypovitaminosis D on circulating NT-proBNP levels in young patients with congenital heart defects (CHD).

DESIGN AND PATIENTS

This cross-sectional study included the assessment of serum 25-hydroxyvitamin D (25OHD), parathyroid function markers, and NT-proBNP levels in a series of 230 young in-patients (117 females, 113 males; 6.4 (4.0-9.1) years (median, interquartile range)) with CHD.

RESULTS

Serum 25OHD levels <20 ng/mL were detected in 55.3% of patients. Optimal 25OHD levels (>30 ng/mL) occurred in 25% of patients. Serum 25OHD levels inversely correlated with age (r = -0.169, P = 0.013) and height standard deviation score (r = -0.269, P = 0.001). After correction for age, 25OHD negatively correlated with serum PTH levels (β = -0.200, P = 0.002). PTH levels above the upper quartile (44 pg/mL) occurred in 32% of hypovitaminosis D patients. Serum NT-proBNP levels were not correlated with 25OHD and PTH levels.

CONCLUSIONS

Half of the young CHD patients were diagnosed with 25OHD deficiency and a third of hypovitaminosis D patients experienced hyperparathyroidism. Nonetheless, serum NT-proBNP levels were not associated with hypovitaminosis D as well as hyperparathyroidism.

Fibroblast Growth Factor 23 Is an Independent and Specific Predictor of Mortality in Patients With Heart Failure and Reduced Ejection Fraction

BACKGROUND

Strategies to improve risk prediction are of major importance in patients with heart failure (HF). Fibroblast growth factor 23 (FGF-23) is an endocrine regulator of phosphate and vitamin D homeostasis associated with an increased cardiovascular risk. We aimed to assess the prognostic effect of FGF-23 on mortality in HF patients with a particular focus on differences between patients with HF with preserved ejection fraction and patients with HF with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

FGF-23 levels were measured in 980 patients with HF enrolled in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study including 511 patients with HFrEF and 469 patients with HF with preserved ejection fraction and a median follow-up time of 8.6 years. FGF-23 was additionally measured in a second cohort comprising 320 patients with advanced HFrEF. FGF-23 was independently associated with mortality with an adjusted hazard ratio per 1-SD increase of 1.30 (95% confidence interval, 1.14-1.48; P<0.001) in patients with HFrEF, whereas no such association was found in patients with HF with preserved ejection fraction (for interaction, P=0.043). External validation confirmed the significant association with mortality with an adjusted hazard ratio per 1 SD of 1.23 (95% confidence interval, 1.02-1.60; P=0.027). FGF-23 demonstrated an increased discriminatory power for mortality in addition to N-terminal pro-B-type natriuretic peptide (C-statistic: 0.59 versus 0.63) and an improvement in net reclassification index (39.6%; P<0.001).

CONCLUSIONS

FGF-23 is independently associated with an increased risk of mortality in patients with HFrEF but not in those with HF with preserved ejection fraction, suggesting a different pathophysiologic role for both entities.

Race and Vitamin D Binding Protein Gene Polymorphisms Modify the Association of 25-Hydroxyvitamin D and Incident Heart Failure: The ARIC (Atherosclerosis Risk in Communities) Study

OBJECTIVES

This study sought to determine if low serum 25-hydroxyvitamin D (25[OH]D) is associated with incident heart failure (HF) and if the association is: 1) partly mediated by traditional cardiovascular risk factors; 2) stronger among whites than blacks; and 3) stronger among those genetically predisposed to having high levels of vitamin D binding protein (DBP).

BACKGROUND

Suboptimal 25(OH)D is a potential cardiovascular risk factor.

METHODS

A total of 12,215 ARIC (Atherosclerosis Risk in Communities) study participants free of HF at baseline (1990 to 1992; median age, 56; 24% black) were followed through 2010. Total serum 25(OH)D was measured at baseline using liquid chromatography-mass spectrometry. Incident HF events were identified by a hospital discharge code of ICD9-428 and parallel International Classification of Diseases codes for HF deaths.

RESULTS

During 21 years of follow-up, 1,799 incident HF events accrued. The association between 25(OH)D and HF varied by race (p-interaction = 0.02). Among whites, risk was 2-fold higher for those in the lowest (≤17 ng/ml) versus highest (≥31 ng/ml) quintile of 25(OH)D. The association was attenuated but remained significant with covariate adjustment. In blacks there was no overall association. In both races, those with low 25(OH)D and the rs7041 G allele, which predisposes to high DBP, were at greater risk (p-interaction = 0.01).

CONCLUSIONS

Low serum 25(OH)D was independently associated with incident HF among whites, but not among blacks. However, in both races, low 25(OH)D was associated with HF risk among those genetically predisposed to high DBP. These findings provide novel insight into metabolic differences that may underlie racial variation in the association between 25(OH)D and cardiovascular risk.

Prevention of Heart Failure in Patients with Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have heightened risk of developing heart failure (HF), yet few clinical studies have directly investigated the pathophysiologic underpinnings or therapeutic strategies to prevent HF. A wide range of clinically available cardiac and renal biomarkers can identify at-risk individuals who would benefit from dietary and lifestyle modifications (exercise prescription, smoking cessation), as well as risk factor modification (blood pressure, glucose, and lipid control). Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have the most consistent data for risk reduction, while other standard HF drugs such as beta-blockers and mineralocorticoid receptor antagonists have promising findings but no large-scale clinical trial evidence for their routine use to prevent the development and progression of HF in this vulnerable population.

Vitamin D supplementation and lipid profile: what does the best available evidence show?

Vitamin D supplements have increasingly been used for the treatment and prevention of osteoporosis. Historically, effects of the vitamin on the cardiovascular (CV) system have been proposed and demonstrated in the literature, including benefits on serum lipids. Although observational studies support an association between increased serum vitamin D levels and a favorable lipid profile, interventional studies have shown no effects. This review presents and analyzes all the related randomized controlled trials (RCTs) identified in the literature from 1987 to present. A systematic literature search was conducted via MEDLINE, Cochrane Library and EMBASE and, out of 19 relevant RCTs identified, only one reported benefits of vitamin D supplementation on lipid profile parameters, while the rest showed no effects or even adverse outcomes, which are highlighted by the only meta-analysis in the field. Attempts to explain the paradox of beneficial findings of observational studies versus discouraging results of interventional studies have been made and the most popular suggests that high serum vitamin D concentrations may not be the cause of good health but its outcome instead, as healthy people are more likely to stay outdoors longer and have better eating habits. For definitive answers to be given, large, well-designed RCTs need to be conducted that will take into account and adjust for dietary consumption as well as serum calcium and parathyroid hormone levels, both of which have been shown to be associated with the CV system. Until then, recommendations for vitamin D supplementation should not change.