Rationale and Plan for Vitamin D Food Fortification: A Review and Guidance Paper.

Vitamin D deficiency can lead to musculoskeletal diseases such as rickets and osteomalacia, but vitamin D supplementation may also prevent extraskeletal diseases such as respiratory tract infections, asthma exacerbations, pregnancy complications and premature deaths. Vitamin D has a unique metabolism as it is mainly obtained through synthesis in the skin under the influence of sunlight (i.e.

Effects of vitamin D supplementation on markers for cardiovascular disease and type 2 diabetes: an individual participant data meta-analysis of randomized controlled trials.

Background: Evidence from randomized controlled trials (RCTs) for the causal role of vitamin D on noncommunicable disease outcomes is inconclusive.

Objective: The aim of this study was to investigate whether there are beneficial or harmful effects of cholecalciferol (vitamin D3) supplementation according to subgroups of remeasured serum 25-hydroxyvitamin D [25(OH)D] on cardiovascular and glucometabolic surrogate markers with the use of individual participant data (IPD) meta-analysis of RCTs.

Design: Twelve RCTs (16 wk to 1 y of follow-up) were included.

Vitamin D supplementation and lipoprotein metabolism: A randomized controlled trial.

Background: Vitamin D deficiency is associated with an unfavorable lipid profile, but whether and how vitamin D supplementation affects lipid metabolism is unclear.

Objective: To examine the effects of vitamin D supplementation on lipid and lipoprotein parameters.

Methods: This is a post hoc analysis of the single-center, double-blind, randomized, placebo-controlled Styrian Vitamin D Hypertension Trial (2011-2014).

Effects of vitamin D supplementation on FGF23: a randomized-controlled trial.

Purpose: Fibroblast growth factor-23 (FGF23) is critical for phosphate homeostasis. Considering the high prevalence of vitamin D deficiency and the association of FGF23 with adverse outcomes, we investigated effects of vitamin D3 supplementation on FGF23 concentrations.

Methods: This is a post-hoc analysis of the Styrian Vitamin D Hypertension trial, a single-center, double-blind, randomized, placebo-controlled trial, conducted from 2011 to 2014 at the Medical University of Graz, Austria.

Are laboratory tests always needed? Frequency and causes of laboratory overuse in a hospital setting.

Background: Inappropriate utilization of laboratory resources is an increasing concern especially in high-throughput facilities. Until now, no reliable information has been published addressing to which extent laboratory results are actually used for clinical decision-making. Therefore, we aimed to close this gap using a novel retrospective approach including a survey of clinicians and nurses.

Non-skeletal health effects of vitamin D supplementation: A systematic review on findings from meta-analyses summarizing trial data.

Background: A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D (25OHD) levels on non-skeletal outcomes. We performed a systematic quantitative review on characteristics of randomized clinical trials (RCTs) included in meta-analyses (MAs) on non-skeletal effects of vitamin D supplementation.

Methods And Findings: We identified systematic reviews (SR) reporting summary data in terms of MAs of RCTs on selected non-skeletal outcomes.

Effects of Vitamin D Supplementation on IGF-1 and Calcitriol: A Randomized-Controlled Trial.

Increasing evidence suggests a possible interaction between vitamin D and insulin-like growth factor-1 (IGF-1). We aimed to investigate effects of vitamin D supplementation on IGF-1 (primary outcome) and calcitriol (1,25(OH)₂D) concentrations (secondary outcome). This is a post-hoc analysis of the Styrian Vitamin D Hypertension Trial-a single-center, double-blind, randomized, placebo-controlled trial (RCT) conducted from 2011 to 2014 at the Medical University of Graz, Austria.

Effects of Vitamin D Supplementation on Bone Turnover Markers: A Randomized Controlled Trial.

Bone turnover markers (BTMs) are used to evaluate bone health together with bone mineral density and fracture assessment. Vitamin D supplementation is widely used to prevent and treat musculoskeletal diseases but existing data on vitamin D effects on markers of bone resorption and formation are inconsistent. We therefore examined the effects of vitamin D supplementation on bone-specific alkaline phosphatase (bALP), osteocalcin (OC), C-terminal telopeptide (CTX), and procollagen type 1 N-terminal propeptide (P1NP).

Vitamin D and mortality: Individual participant data meta-analysis of standardized 25-hydroxyvitamin D in 26916 individuals from a European consortium.

Background: Vitamin D deficiency may be a risk factor for mortality but previous meta-analyses lacked standardization of laboratory methods for 25-hydroxyvitamin D (25[OH]D) concentrations and used aggregate data instead of individual participant data (IPD). We therefore performed an IPD meta-analysis on the association between standardized serum 25(OH)D and mortality.

Methods: In a European consortium of eight prospective studies, including seven general population cohorts, we used the Vitamin D Standardization Program (VDSP) protocols to standardize 25(OH)D data.

Beneficial Effects of UV-Radiation: Vitamin D and beyond.

Aside from its well-known effects on bone and mineral metabolism, vitamin D may also play an important role in extra-skeletal processes like immunologic diseases, cancer, or cardiovascular diseases. Even though meta-analyses showed that vitamin D supplementation reduces fractures, falls, and overall mortality, its potential benefits did not find universal acclaim. Several health care authorities published Recommended Dietary Allowances (RDAs) for vitamin D, most of them ranging from 600 to 800 international units (IU) per day, corresponding to a serum level of 25-hydroxyvitamin D of at least 20 ng/mL (50 nmol/L).

Parathyroid hormone, aldosterone-to-renin ratio and fibroblast growth factor-23 as determinants of nocturnal blood pressure in primary hyperparathyroidism: the eplerenone in primary hyperparathyroidism trial.

Objectives: The high prevalence of arterial hypertension in primary hyperparathyroidism (pHPT) is largely unexplained. Apart from parathyroid hormone (PTH), the mineral hormones fibroblast growth factor (FGF)-23 and aldosterone-to-renin ratio (ARR) are upregulated in pHPT. We aimed to determine whether nocturnal blood pressure (BP) is related with PTH, FGF-23 or ARR in a relatively large sample of pHPT patients.

Effects of Vitamin D Supplementation on Serum 25-Hydroxyvitamin D Concentrations in Cirrhotic Patients: A Randomized Controlled Trial.

Background: The liver is crucial for 25-hydroxyvitamin D (25(OH)D) metabolism, and vitamin D deficiency is highly prevalent in patients with cirrhosis and predicts adverse outcomes. We aimed to evaluate whether vitamin D supplementation in patients with cirrhosis is effective in increasing 25(OH)D serum concentrations. Secondary outcome measures included liver function tests (aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (GGT), and alkaline phosphatase (AP)), albumin, International Normalized Ratio (INR), bilirubin, the liver fibrosis marker hyaluronic acid, and parameters of mineral metabolism including parathyroid hormone (PTH).

Effects of Vitamin D Supplementation on Plasma Aldosterone and Renin-A Randomized Placebo-Controlled Trial.

Increasing evidence describes a possible interplay between vitamin D insufficiency with increased aldosterone. The authors sought to evaluate the effect of vitamin D supplementation on plasma aldosterone concentration (PAC) in patients with hypertension and 25-hydroxyvitamin D[25(OH)D] insufficiency. The Styrian Vitamin D Hypertension Trial was a single-center, double-blind, placebo-controlled randomized clinical trial conducted from 2011 to 2014.

Effect of eplerenone on parathyroid hormone levels in patients with primary hyperparathyroidism: results from the EPATH randomized, placebo-controlled trial.

Background: Accumulating evidence points toward mutual interaction between parathyroid hormone (PTH) and aldosterone as potential mechanism for increasing cardiovascular risk in primary hyperparathyroidism (pHPT).

Methods: The Eplerenone on parathyroid hormone levels in patients with primary hyperparathyroidism (EPATH) trial is a single-center, randomized, double-blind, parallel-group, placebo-controlled trial. The primary aim is to evaluate the effects of the mineralocorticoid receptor antagonist eplerenone on plasma intact PTH (iPTH) concentration in patients with pHPT.

Vitamin D Supplementation and Hemoglobin Levels in Hypertensive Patients: A Randomized Controlled Trial.

Epidemiological evidence suggests that circulating 25-hydroxyvitamin D (25OHD) levels are inversely associated with hemoglobin (Hb) levels and anemia risk. We evaluated whether vitamin D supplementation improves Hb levels and reduces anemia risk in hypertensive patients. Two hundred patients with 25OHD levels <75 nmol/L who attended the Styrian Vitamin D Hypertension Trial were included, of whom 188 completed the trial.

Vitamin D and Mortality.

In this narrative review, we aim to summarize and discuss the current evidence linking vitamin D and mortality. Low 25-hydroxyvitamin D [25(OH)D] concentrations are associated with an increased risk of mortality. This has been shown in different cohort studies including general populations, as well as various patient cohorts.

Aldosterone-to-Renin Ratio Is Associated With Reduced 24-Hour Heart Rate Variability and QTc Prolongation in Hypertensive Patients.

Aldosterone is considered to exert direct effects on the myocardium and the sympathetic nervous system. Both QT time and heart rate (HR) variability (HRV) are considered to be markers of arrhythmic risk and autonomous dysregulation. In this study, we investigated the associations between aldosterone, QT time, and HRV in patients with arterial hypertension.

Plasma Parathyroid Hormone Is Independently Related to Nocturnal Blood Pressure in Hypertensive Patients: The Styrian Hypertension Study.

High parathyroid hormone (PTH) has been linked with high blood pressure (BP), but the relationship with 24-hour ambulatory blood pressure monitoring is largely unknown. The authors therefore analyzed cross-sectional data of 292 hypertensive patients participating in the Styrian Hypertension Study (mean age, 61±11 years; 53% women). Median plasma PTH (interquartile range) determined after an overnight fast was 49 pg/mL (39-61), mean daytime BP was 131/80±12/9 mm Hg, and mean nocturnal BP was 115/67±14/9 mm Hg.

Homoarginine in the renal and cardiovascular systems.

Homoarginine (hArg) is an endogenous, nonproteinogenic amino acid which differs from arginine by an additional methylene (CH2) group in the backbone. In this brief narrative review, we summarize the current literature on hArg in the renal and cardiovascular systems. Epidemiological studies have identified low hArg levels as an independent risk marker for cardiovascular, cerebrovascular, and renal diseases as well as for mortality.

Effects of vitamin D on blood pressure and cardiovascular risk factors: a randomized controlled trial.

Unlabelled: Vitamin D deficiency is a risk factor for arterial hypertension, but randomized controlled trials showed mixed effects of vitamin D supplementation on blood pressure (BP). We aimed to evaluate whether vitamin D supplementation affects 24-hour systolic ambulatory BP monitoring values and cardiovascular risk factors. The Styrian Vitamin D Hypertension Trial is a single-center, double-blind, placebo-controlled study conducted from June 2011 to August 2014 at the endocrine outpatient clinic of the Medical University of Graz, Austria.

Vitamin D in preventive medicine.

The global burden of vitamin D deficiency is of great concern for public health. Meta-analyses of randomized controlled trials (RCTs) have shown that vitamin D supplementation reduces fractures, falls, and mortality. These findings are, however, not universally accepted and there exists certain controversy regarding the potential benefits of vitamin D.

Homoarginine in patients with primary hyperparathyroidism.

Background: Low levels of the amino acid homoarginine and parathyroid hormone (PTH) excess are both independently related to an increased risk of cardiovascular morbidity and mortality. Accumulating evidence points to a mutual interplay between homoarginine and PTH. The authors therefore aimed to investigate circulating homoarginine levels in patients with and without primary hyperparathyroidism (PHPT).

Associations of daytime, nighttime, and 24-hour heart rate with four distinct markers of inflammation in hypertensive patients: the Styrian Hypertension Study.

The current study assessed which measure of heart rate (HR) is most associated with inflammatory activity. Among 368 hypertensive patients (mean age±standard deviation, 60.6±10.

Associations of methylarginines and homoarginine with diastolic dysfunction and cardiovascular risk factors in patients with preserved left ventricular ejection fraction.

Background: Asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and homoarginine are considered to modulate nitric oxide synthesis. We evaluated whether ADMA, SDMA, and homoarginine are associated with diastolic dysfunction.

Methods And Results: We investigated primary care patients at cardiovascular risk with preserved left ventricular ejection fraction from the multicenter DIAST-CHF study.

Development of a liquid chromatography-mass spectrometry method for the determination of the neurotoxic quinolinic acid in human serum.

Background: Quinolinic acid (QA) is thought to be one of the most important metabolites of the kynurenine pathway with the highest biological activity in apoptotic responses and neurodegenerative diseases. The determination of QA might be of clinical relevance in different patient groups, but currently, only a few laborious methods with high levels of sample volume consumption are available.

Methods: We developed and validated a simple liquid chromatography-tandem mass spectrometric (LC-tandem MS) method for the determination of QA in human serum with low sample volume requirements.