title: 25-hydroxyvitamin D and risk of myocardial infarction in men: a prospective study. The Effects of Vitamin D Supplementation on Physical Function and Quality of Life in Older Patients With Heart Failure: A Randomized Controlled Trial No Effect of High-Dose Vitamin D Supplementation on Glycemic Status or Cardiovascular Risk Factors in Subjects With Prediabetes Vitamin D3 supplementation has no effect on conventional cardiovascular risk factors: a parallel-group, double-blind, placebo-controlled RCT. Vitamin D supplementation and endothelial function in vitamin D deficient HIV-infected patients: a randomized placebo-controlled trial. Vitamin D supplementation improves cytokine profiles in patients with congestive heart failure: a double-blind, randomized, placebo-controlled trial. Vitamin D intake to attain a desired serum 25-hydroxyvitamin D concentration. Effect of short-term vitamin D supplementation on markers of vascular health in South Asian women living in the UK--a randomised controlled trial. Does vitamin D improve liver enzymes, oxidative stress, and inflammatory biomarkers in adults with non-alcoholic fatty liver disease? A randomized clinical trial Effect of cholecalciferol supplementation during winter months in patients with hypertension: a randomized, placebo-controlled trial. Effects of high-dose cholecalciferol on serum markers of inflammation and immunity in patients with early chronic kidney disease Impact of Vitamin D Supplementation on Arterial Vasomotion, Stiffness and Endothelial Biomarkers in Chronic Kidney Disease Patients Efficacy of different doses and time intervals of oral vitamin D supplementation with or without calcium in elderly nursing home residents Vitamin D and Serum Cytokines in a Randomized Clinical Trial Effects of vitamin D on cardiovascular disease risk factors in polycystic ovary syndrome women with vitamin D deficiency The effect of vitamin D replacement on markers of vascular health in stroke patients - a randomised controlled trial. Vitamin D supplementation affects serum high-sensitivity C-reactive protein, insulin resistance, and biomarkers of oxidative stress in pregnant women. Cholecalciferol treatment to reduce blood pressure in older patients with isolated systolic hypertension: the VitDISH randomized controlled trial. Effects of vitamin D supplementation on markers of vascular function after myocardial infarction--a randomised controlled trial. Effects of cholecalciferol on functional, biochemical, vascular, and quality of life outcomes in hemodialysis patients. Impact of vitamin D supplementation on markers of inflammation in adults with cystic fibrosis hospitalized for a pulmonary exacerbation Effect of estrogen and progesterone on the expression of 1, 25-dihydroxyvitamin D receptors mRNA in the liver of ovariectomized rats. Randomized controlled trial of vitamin D supplement on endothelial function in patients with type 2 diabetes. Randomized controlled trial of cholecalciferol supplementation in chronic kidney disease patients with hypovitaminosis D. Vitamin D3 supplementation for 16 weeks improves flow-mediated dilation in overweight African-American adults. Effect of high doses of vitamin D on arterial properties, adiponectin, leptin and glucose homeostasis in type 2 diabetic patients. Short and long-term variations in serum calciotropic hormones after a single very large dose of ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3) in the elderly. Vitamin D improves endothelial function in patients with Type 2 diabetes mellitus and low vitamin D levels. Effect of a single, oral, high-dose vitamin D supplementation on endothelial function in patients with peripheral arterial disease: a randomised controlled pilot study. The effects of vitamin D repletion on endothelial function and inflammation in patients with coronary artery disease
abstract: BACKGROUND Vitamin D deficiency may be involved in the development of atherosclerosis and coronary heart disease in humans . METHODS We assessed prospect ively whether plasma 25-hydroxyvitamin D ( 25[OH]D ) concentrations are associated with risk of coronary heart disease . A nested case-control study was conducted in 18,225 men in the Health Professionals Follow-up Study ; the men were aged 40 to 75 years and were free of diagnosed cardiovascular disease at blood collection . The blood sample s were returned between April 1 , 1993 , and November 30 , 1999 ; 99 % were received between April 1 , 1993 , and November 30 , 1995 . During 10 years of follow-up , 454 men developed nonfatal myocardial infa rct ion or fatal coronary heart disease . Using risk set sampling , controls ( n = 900 ) were selected in a 2:1 ratio and matched for age , date of blood collection , and smoking status . RESULTS After adjustment for matched variables , men deficient in 25(OH)D ( < or=15 ng/mL [ to convert to nanomoles per liter , multiply by 2.496 ] ) were at increased risk for MI compared with those considered to be sufficient in 25(OH)D ( > or=30 ng/mL ) ( relative risk [ RR ] , 2.42 ; 95 % confidence interval [ CI ] , 1.53 - 3.84 ; P < .001 for trend ) . After additional adjustment for family history of myocardial infa rct ion , body mass index , alcohol consumption , physical activity , history of diabetes mellitus and hypertension , ethnicity , region , marine omega-3 intake , low- and high-density lipoprotein cholesterol levels , and triglyceride levels , this relationship remained significant ( RR , 2.09 ; 95 % CI , 1.24 - 3.54 ; P = .02 for trend ) . Even men with intermediate 25(OH)D levels were at elevated risk relative to those with sufficient 25(OH)D levels ( 22.6 - 29.9 ng/mL : RR , 1.60 [ 95 % CI , 1.10 - 2.32 ] ; and 15.0 - 22.5 ng/mL : RR , 1.43 [ 95 % CI , 0.96 - 2.13 ] , respectively ) . CONCLUSION Low levels of 25(OH)D are associated with higher risk of myocardial infa rct ion in a grade d manner , even after controlling for factors known to be associated with coronary artery disease Background —Low 25-hydroxyvitamin D levels , commonly found in older patients with heart failure , may contribute to the chronic inflammation and skeletal myopathy that lead to poor exercise tolerance . We tested whether vitamin D supplementation of patients with heart failure and vitamin D insufficiency can improve physical function and quality of life . Methods and Results —In a r and omized , parallel group , double-blind , placebo-controlled trial , patients with systolic heart failure aged ≥70 years with 25-hydroxyvitamin D levels < 50 nmol/L ( 20 ng/mL ) received 100000 U of oral vitamin D2 or placebo at baseline and 10 weeks . Outcomes measured at baseline , 10 weeks , and 20 weeks were 6-minute walk distance , quality of life ( Minnesota score ) , daily activity measured by accelerometry , Functional Limitations Profile , B-type natriuretic peptide , and tumor necrosis factor-&agr;. Participants in the vitamin D group had an increase in their 25-hydroxyvitamin D levels compared with placebo at 10 weeks ( 22.9 versus 2.3 nmol/L [ 9.2 versus 0.9 ng/mL ] ; P<0.001 ) and maintained this increase at 20 weeks . The 6-minute walk did not improve in the treatment group relative to placebo . No significant benefit was seen on timed up and go testing , subjective measures of function , daily activity , or tumor necrosis factor . Quality of life worsened by a small , but significant amount in the treatment group relative to placebo . B-type natriuretic peptide decreased in the treatment group relative to placebo ( −22 versus + 78 pg/mL at 10 weeks ; P=0.04 ) . Conclusions —Vitamin D supplementation did not improve functional capacity or quality of life in older patients with heart failure with vitamin D insufficiency . Clinical Trial Registration —www.controlled-trials.com . Identifier : IS RCT N51372896 OBJECTIVE In observational studies , low serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations have been associated with insulin resistance and other risk factors for cardiovascular disease . RESEARCH DESIGN AND METHODS We present 1-year data from an ongoing 5-year trial in 511 individuals with impaired fasting glucose ( IFG ) and /or impaired glucose tolerance ( IGT ) r and omly assigned to 20,000 IU/week vitamin D3 or placebo .  An oral glucose tolerance test was performed at baseline and after 1 year . RESULTS Mean baseline serum 25(OH)D was 59.9 nmol/L and 61.1 nmol/L in the vitamin D and placebo groups , respectively , and increased by 45.8 nmol/L and 3.4 nmol/L , respectively . With adjustment for baseline concentrations , no differences in measures of glucose metabolism , insulin secretion or sensitivity , blood pressure , or hs-CRP were found after 1 year . There was a slight , but significant decrease in total and LDL cholesterol in the vitamin D group compared with the placebo group , but as there was also a decrease in HDL cholesterol , the change in the total/HDL cholesterol ratio did not differ significantly . Only analyzing subjects with 25(OH)D < 50 nmol/L did not change the results . CONCLUSIONS This study shows that vitamin D supplementation does not improve glycemic indices , blood pressure , or lipid status in subjects with IFG and /or IGT CONTEXT Observational studies show an association between low vitamin D status assessed by circulating 25-hydroxyvitamin D and cardiovascular events and mortality . Data from r and omized controlled trials are limited . OBJECTIVE The aim of this study was to test whether daily doses of vitamin D(3 ) at 400 or 1000 IU/d for 1 yr affected conventional markers of cardiovascular disease ( CVD ) risk . DESIGN We conducted a parallel-group , double-blind , placebo-controlled r and omized controlled trial . R and omization was computer generated . Participants and study investigators were blinded to intervention groupings throughout the trial . SETTING The study was conducted at the Clinical Research Facility , University of Aberdeen , United Kingdom . PARTICIPANTS A total of 305 healthy postmenopausal women aged 60 - 70 yr were recruited for the study . INTERVENTION Each woman received a daily capsule of 400 or 1000 IU vitamin D(3 ) or placebo r and omly allocated . MAIN OUTCOME MEASURES Primary outcomes were serum lipid profile [ total , high-density lipoprotein , and low-density lipoprotein cholesterol ; triglycerides ; and apolipoproteins A-1 and B100 ] , insulin resistance ( homeostatic model assessment ) , inflammatory biomarkers ( high-sensitivity C-reactive protein , IL-6 , soluble intracellular adhesion molecule-1 ) , and blood pressure . RESULTS A total of 265 ( 87 % ) participants completed all study visits . Small differences between groups for serum apolipoprotein B100 change [ repeated measures ANOVA , P=0.04 ; mean ( sd ) , -1.0 ( 10.0 ) mg/dl ( 400 IU ) ; -1.0 ( 10.0 ) mg/dl ( 1000 IU ) ; and + 0.02 ( 10.0 ) mg/dl ( placebo ) ] were not considered clinical ly significant . Other systemic markers for CVD risk remained unchanged . There was significant seasonal variation in systolic and diastolic blood pressure independent of vitamin D dose ( P<0.001 , linear mixed model ) . Mean ( sd ) reduction in systolic blood pressure from winter to summer was -6.6 ( 10.8 ) mm Hg . CONCLUSIONS Improving vitamin D status through dietary supplementation is unlikely to reduce CVD risk factors . Confounding of seasonality should be recognized and addressed in future studies of vitamin BACKGROUND Studies suggest that vitamin D deficiency is a risk factor for cardiovascular disease and diabetes . Vitamin D deficiency is prevalent in HIV patients but the effect of vitamin D supplementation on cardiovascular risk in this population is unknown . METHODS We conducted a r and omized , double-blind , placebo-controlled trial among 45 HIV-infected adults in Clevel and ( OH , USA ) on stable antiretroviral therapy with durable virological suppression and a baseline serum 25-hydroxyvitamin D level of ≤20 ng/ml . Participants were r and omized 2:1 to vitamin D3 4,000 IU daily or placebo  for 12 weeks . The primary outcome was a change in flow-mediated brachial artery dilation ( FMD ) . RESULTS Baseline demographics were similar except for age ( vitamin D versus placebo , mean ±sd 47 ±8 versus 40 ±10 years ; P=0.009 ) . Both groups had reduced FMD at baseline ( median values 2.9 % [ IQR 1.6 - 4.8 ] for vitamin D versus 2.5 % [ IQR 1.7 - 6.4 ] for placebo ; P=0.819 ) . Despite an increase in the concentration of serum 25-hydroxyvitamin D from baseline to 12 weeks ( 5.0 ng/ml [ IQR -0.9 - 7.4 ] versus -1.9 ng/ml [ IQR -4.0 - 0.1 ] for vitamin D versus placebo , respectively ; P=0.003 ) , there was no difference in FMD change ( 0.55 % [ IQR -1.05 - 2.13 ] versus 0.29 % [ IQR -1.61 - 1.77 ] ; P=0.748 ) . Vitamin D supplementation was associated with a decrease in total and non-high-density lipoprotein cholesterol , and an increase in indices of insulin resistance . CONCLUSIONS Among HIV-infected individuals with vitamin D deficiency , supplementation with 4,000 IU vitamin D3 daily for 12 weeks modestly improved vitamin D status and cholesterol but worsened insulin resistance without change in endothelial function . The mechanisms of resistance to st and ard doses of vitamin D and the complex role of vitamin D in glucose metabolism in this population require further investigation BACKGROUND Elevated circulating concentrations of proinflammatory cytokines may contribute to the pathogenesis of congestive heart failure ( CHF ) . In vitro studies suggest that vitamin D suppresses proinflammatory cytokines and increases antiinflammatory cytokines . OBJECTIVE We evaluated the effect of vitamin D supplementation on the survival rate and different biochemical variables in patients with CHF . DESIGN One hundred twenty-three patients r and omly received either 50 mug vitamin D(3)/d plus 500 mg Ca/d [ D(+ ) group ] or placebo plus 500 mg Ca/d [ D(- ) group ] for 9 mo . Biochemical variables were assessed at baseline and after 9 mo . The survival rate was calculated for a follow-up period of 15 mo . RESULTS Ninety-three patients completed the study . Significant treatment effects were observed on logarithmic-transformed serum concentrations of 25-hydroxyvitamin D ( P = 0.001 ) , parathyroid hormone ( P = 0.007 ) , tumor necrosis factor alpha ( P = 0.006 ) , and interleukin 10 ( P = 0.042 ) . 25-Hydroxyvitamin D increased by 26.8 ng/mL in the D(+ ) group but increased only by 3.6 ng/mL in the D(- ) group . Compared with baseline , parathyroid hormone was significantly lower and the antiinflammatory cytokine interleukin 10 was significantly higher in the D(+ ) group after 9 mo . The proinflammatory cytokine tumor necrosis factor alpha increased in the D(- ) group but remained constant in the D(+ ) group . The survival rate did not differ significantly between the study groups during the follow-up period . CONCLUSIONS Vitamin D(3 ) reduces the inflammatory milieu in CHF patients and might serve as a new antiinflammatory agent for the future treatment of the disease . Our data provide evidence for the involvement of an impaired vitamin D-parathyroid hormone axis in the progression of CHF BACKGROUND Indirect evidence suggests that optimal vitamin D status is achieved with a serum 25-hydroxyvitamin D [ 25(OH)D ] concentration > 75 nmol/L. OBJECTIVE We aim ed to determine the intake of vitamin D(3 ) needed to raise serum 25(OH)D to > 75 nmol/L. DESIGN The design was a 6-mo , prospect i ve , r and omized , double-blinded , double-dummy , placebo-controlled study of vitamin D(3 ) supplementation .  Serum 25(OH)D was measured by  radioimmunoassay . Vitamin D(3 ) intake was adjusted every 2 mo by use of an algorithm based on serum 25(OH)D concentration . RESULTS A total of 138 subjects entered the study . After 2 dose adjustments , almost all active subjects attained concentrations of 25(OH)D > 75 nmol/L , and no subjects exceeded 220 nmol/L. The mean ( + /-SD ) slope at 9 wk [ defined as 25(OH)D change/baseline dose ] was 0.66 + /- 0.35 (nmol/L)/(microg/d ) and did not differ statistically between blacks and whites . The mean daily dose was 86 microg ( 3440 IU ) . The use of computer simulations to obtain the most participants within the range of 75 - 220 nmol/L predicted an optimal daily dose of 115 microg/d ( 4600 IU ) . No hypercalcemia or hypercalciuria was observed . CONCLUSIONS Determination of the intake required to attain serum 25(OH)D concentrations > 75 nmol/L must consider the wide variability in the dose-response curve and basal 25(OH)D concentrations . Projection of the dose-response curves observed in this convenience sample onto the population of the third National Health and Nutrition Examination Survey suggests a dose of 95 microg/d ( 3800 IU ) for those above a 25(OH)D threshold of 55 nmol/L and a dose of 125 microg/d ( 5000 IU ) for those below that threshold OBJECTIVE Low vitamin D levels and risk factors for vascular disease are both common in South Asian women . This trial evaluated whether vitamin D supplementation could improve markers of vascular health in South Asian women with low 25-hydroxyvitamin D levels . METHODS Parallel-group , double-blind , r and omised placebo-controlled trial . Healthy South Asian women with baseline serum 25-hydroxyvitamin D levels of < 75 nmol/L were r and omised to receive a single dose of 100,000 units oral vitamin D3 or matching placebo . Outcomes were measured at baseline , 4 and 8 weeks . The primary outcome was change in endothelial function measured using brachial artery flow-mediated dilatation . Secondary outcomes included blood pressure , arterial stiffness , microvascular function measured using laser Doppler iontophoresis , insulin resistance , serum lipids , circulating markers of inflammation , thrombosis and adipokines . RESULTS 50 women were r and omised , 25 to each group . Mean age was 41 years ; mean baseline 25-hydroxyvitamin D level was 27 nmol/L.  25-Hydroxyvitamin D levels rose in the vitamin D group relative to the placebo group by 4 weeks ( 16 nmol/L , 95 % CI 11 to 21 , p < 0.001 ) . There was no improvement in flow-mediated dilatation in the vitamin D group relative to placebo at 4 weeks ( 0.1 % , 95 % CI -0.9 to 1.1 , p = 0.84 ) or 8 weeks ( 0.0 % , 95 % CI -1.4 to 1.4 , p = 0.98 ) . There was no improvement in cholesterol , insulin resistance or markers of inflammation . Both platelet activation inhibitor-1 and tissue plasminogen activator levels fell significantly in the vitamin D group relative to placebo at 8 weeks . CONCLUSION A single large dose of vitamin D3 did not improve blood pressure or endothelial function in South Asian women with low baseline 25-hydroxyvitamin D levels . TRIAL REGISTRATION IS RCT N75081811 The aim of this study was to investigate the effects of vitamin D supplementation on serum aminotransferases , insulin resistance , oxidative stress , and inflammatory biomarkers in adult patients with non-alcoholic fatty liver disease ( NAFLD ) . Fifty-three patients with NAFLD were enrolled in a parallel , double-blind , placebo-controlled study . The patients were r and omly allocated to receive either one oral pearl consisting of 50,000 IU vitamin D3 ( n = 27 ) or a placebo ( n = 26 ) , every 14 days for 4 months . Serum aminotransferases , high-sensitive C-reactive protein ( hs-CRP ) , tumor necrosis factor α , malondialdehyde ( MDA ) , total antioxidant capacity , transforming growth factor β1 , as well as grade of hepatic steatosis and homeostasis model assessment of insulin resistance were assessed pre- and post-intervention . In patients who received vitamin D supplement compared to the controls , the median of serum 25(OH)D3 significantly increased ( 16.2 vs. 1.6 ng/ml , P < 0.001 ) . This increase accompanied by significant decrease in serum MDA ( −2.09 vs. −1.23 ng/ml , P = 0.03 ) and near significant changes in serum hs-CRP ( −0.25 vs. 0.22 mg/l , P = 0.06 ) . These between-group differences remained significant even after controlling for baseline covariates . Other variables showed no significant changes . Improved vitamin D status led to amelioration in serum hs-CRP and MDA in patients with NAFLD . This might be considered as an adjunctive therapy to attenuate systemic inflammation and lipid peroxidation alongside other treatments for NAFLD patients BACKGROUND Low 25-hydroxy-vitamin D ( 25(OH)D ) levels are inversely related to blood pressure ( BP ) and have been associated with incident hypertension . In people living at northern latitudes diminished cholecalciferol synthesis in the winter increases the risk of vitamin D deficiency . We wanted to test the hypothesis that daily cholecalciferol supplementation in the winter lowers BP in patients with hypertension . METHODS We investigated the effect of 75 µg ( 3,000 IU ) cholecalciferol per day in a r and omized , placebo-controlled , double-blind study in 130 hypertensive patients residing in Denmark ( 56º N ) . Ambulatory BP ( 24-h BP ) and arterial stiffness were measured before and after 20 weeks of treatment , that took place between October and March . RESULTS A total of 112 patients ( mean age 61 ± 10 ) with a baseline p-25(OH)D of 23 ± 10 ng/ml completed the study . Compared with placebo , a nonsignificant 3/1 mm Hg ( P = 0.26/0.18 ) reduction was found in 24-h BP . In patients with vitamin D insufficiency ( < 32 ng/ml ) at baseline ( n =  92 ) , 24-h BP decreased by 4/3 mm Hg ( P = 0.05/0.01 ) . Central BP ( CBP ) estimated by applanation tonometry and calibrated with a st and ardized office BP was reduced by 7/2 mm Hg ( P = 0.007/0.15 ) vs. placebo . No differences in carotid-femoral pulse wave velocity ( PWV ) or central augmentation index ( AIx ) were found between treatment arms . CONCLUSIONS Cholecalciferol supplementation , by a dose that effectively increased vitamin D levels , did not reduce 24-h BP , although central systolic BP decreased significantly . In a post-hoc subgroup analysis of 92 subjects with baseline p-25(OH)D levels < 32 ng/ml , significant decreases in 24-h systolic and diastolic BP occurred during cholecalciferol supplementation Background / objectives : Vitamin D has anti-inflammatory and immune-regulating properties . We aim ed to determine if high-dose cholecalciferol supplementation for 1 year in subjects with early chronic kidney disease ( CKD ) improved circulating markers of inflammation and immunity . Subjects/ methods : In this double-blind , r and omized , placebo-controlled trial , 46 subjects with early CKD ( stages 2 and 3 ) were supplemented with oral cholecalciferol ( 50 000 IU weekly for 12 weeks followed by 50 000 IU every other week for 40 weeks ) or a matching placebo for 1 year . Serum tumor necrosis factor-α , interleukin-6 , monocyte chemoattractant protein-1 ( MCP-1 ) , interferon gamma-induced protein-10 and neutrophil gelatinase-associated lipocalin were measured at baseline , 12 weeks and 1 year . Serum cathelicidin ( LL-37 ) was measured at baseline and 12 weeks . An in vitro experiment was performed to investigate the effect of 1,25-dihydroxyvitamin D3 ( 1,25(OH)2D3 ) treatment on MCP-1 secretion in THP-1 monocytes activated with lipopolysaccharide ( LPS ) and Pseudomonas aeruginosa . Results : By 12 weeks , serum MCP-1 decreased in the cholecalciferol group ( 66.2±2.5 to 60.8±2.6 pg/ml , group-by-time interaction P=0.02 ) but was not different from baseline at 1 year . Other markers of inflammation and immunity did not change . In vitro , LPS- and Pseudomonas-activated monocytes treated with 1,25(OH)2D3 had significantly less MCP-1 secretion compared with untreated cells . Conclusions : High-dose cholecalciferol  decreased serum MCP-1 concentrations by 12 weeks in patients with early CKD , although the decrease was not maintained for the remainder of the year . In vitro results confirm an MCP-1-lowering effect of vitamin D. Future studies should determine if vitamin D-mediated reductions in MCP-1 concentrations reflect improved clinical outcomes Background Cardiovascular events are frequent and vascular endothelial function is abnormal in patients with chronic kidney disease ( CKD ) . We demonstrated endothelial dysfunction with vitamin D deficiency in CKD patients ; however the impact of cholecalciferol supplementation on vascular stiffness and vasomotor function , endothelial and bone biomarkers in CKD patients with low 25-hydroxy vitamin D [ 25(OH)D ] is unknown , which this study investigated . Methods We assessed non-diabetic patients with CKD stage 3/4 , age 17–80 years and serum 25(OH)D < 75 nmol/L.  Brachial artery Flow Mediated Dilation ( FMD ) , Pulse Wave Velocity ( PWV ) , Augmentation Index ( AI ) and circulating blood biomarkers were evaluated at baseline and at 16 weeks . Oral 300,000 units cholecalciferol was administered at baseline and 8-weeks . Results Clinical characteristics of 26 patients were : age 50±14 ( mean±1SD ) years , eGFR 41±11 ml/min/1.73 m2 , males 73 % , dyslipidaemia 36 % , smokers 23 % and hypertensives 87 % .  At 16-week serum 25(OH)D and calcium increased ( 43±16 to 84±29 nmol/L , p<0.001 and 2.37±0.09 to 2.42±0.09 mmol/L ; p = 0.004 , respectively ) and parathyroid hormone decreased ( 10.8±8.6 to 7.4±4.4 ; p = 0.001 ) . FMD improved from 3.1±3.3 % to 6.1±3.7 % , p = 0.001 . Endothelial biomarker concentrations decreased : E-Selectin from 5666±2123 to 5256±2058 pg/mL ; p = 0.032 , ICAM-1 , 3.45±0.01 to 3.10±1.04 ng/mL ; p = 0.038 and VCAM-1 , 54±33 to 42±33 ng/mL ; p = 0.006 . eGFR , BP , PWV , AI , hsCRP , von Willebr and factor and Fibroblast Growth Factor-23 , remained unchanged . Conclusion This study demonstrates for the first time improvement of endothelial vasomotor and secretory functions with vitamin D in CKD patients without significant adverse effects on arterial stiffness , serum calcium or FGF-23 . Trial Registration Clinical Trials.gov Summary The effect of equivalent oral doses of vitamin D3 600 IU/day , 4200 IU/week and 18,000 IU/month on vitamin D status was compared in a r and omized clinical trial in nursing home residents . A daily dose was more effective than a weekly dose , and a monthly dose was the least effective . Introduction It is assumed that equivalent daily , weekly or monthly doses of vitamin D3 equally influence vitamin D status . This was investigated in a r and omized clinical trial in nursing home residents . Methods The study was performed in ten nursing homes including 338 subjects ( 76 male and 262 female ) , with a mean age of 84 ( ± SD 6.3 years ) . They received oral vitamin D3 either 600 IU/day , or 4200 IU/week , or 18,000 IU/month or placebo . After 4 months , calcium was added during 2 weeks , 320 mg/day or 640 mg/day or placebo . Outcome : serum levels of 25-hydroxyvitamin D ( 25(OH)D ) , parathyroid hormone ( PTH ) and bone turnover markers . Statistical approach : linear multilevel analysis . Results At baseline , mean serum 25(OH)D was 25.0 nmol/L ( SD 10.9 ) , and in 98 % , it was lower than 50 nmol/L. After 4 months , mean serum 25(OH)D levels increased to 62.5 nmol/L ( after daily vitamin D3 69.9 nmol/L , weekly 67.2 nmol/L and monthly 53.1 nmol/L , P < 0.001 between groups ) . Median serum PTH levels decreased by 23 % ( p < 0.001 ) . Bone turnover markers did not decrease . Calcium supplementation had no effect on serum PTH and bone turnover . Conclusion Daily vitamin D was more effective than weekly , and monthly administration was the least effective Background . The role of vitamin D in the body 's ability to fight influenza and URI 's may be dependent on regulation of specific cytokines that participate in the host inflammatory response . The aim of this study was to test the hypothesis that vitamin D can influence intracellular signaling to regulate the production of cytokines . Subjects and Methods . This study was a 3-month prospect i ve placebo-controlled trial of vitamin D3 supplementation in ambulatory adults [ Li-Ng et al. , 2009 ] . 162 volunteers were r and omized to receive either 50 μg/d ( 2000 IU ) of vitamin D3 or matching placebo . 25(OH)D and the levels of 10 different cytokines ( IL-2 , 4 , 5 , 6 , 8 , 10 , 13 , GM-CSF , IFN-γ , TNF-α ) were measured in the serum of participants at baseline and the final visit . There were 6 drop-outs from the active vitamin D group and 8 from the placebo group . Results . In the active vitamin D group , we found a significant median percent decline in levels of GM-CSF ( −62.9 % , P < .0001 ) , IFN-γ ( −38.9 % , P < .0001 ) , IL-4 ( −50.8 % , P = .001 ) , IL-8 ( −48.4 % , P < .0001 ) , and IL-10 ( −70.4 % , P < .0001 ) . In the placebo group , there were significant declines for GM-CSF ( −53.2 % , P = .0007 ) and IFN-γ ( −34.4 % , P = .0011 ) . For each cytokine , there was no significant difference in the rate of decline between the two groups . 25(OH)D levels increased in the active vitamin D group from a mean of 64.3 ± 25.4 nmol/L to 88.5 ± 23.2 nmol/L. Conclusions . The present study did not show that vitamin D3 supplementation changed circulating cytokine levels among healthy adults Background : Vitamin D deficiency is prevalent among women , including patients with polycystic ovary syndrome ( PCOS ) . Some studies have suggested that vitamin D may have a role in cardiovascular disease ( CVD ) . There is very limited data on the vitamin D effect on CVD risk factors in women with PCOS and vitamin D deficiency . Aim : To investigate the effect of cholecalciferol on CVD risk factors in PCOS women with vitamin D deficiency . Methods : The study was a r and omized , placebo-controlled , double blinded trial . Fifty PCOS women with vitamin D deficiency ( vitamin D , no.=24 ; placebo , no.=26 ) aged 20–40 yr , were r and omly assigned to receive 3 oral capsules of 50 , 000 IU vitamin D3 or a placebo ( one capsule every 20 days ) for two months . Serum vitamin D , PTH , lipid profile , apolipoprotein AI ( APO-AI ) , and high sensitive C- reactive protein ( hs-CRP ) were measured at baseline and after treatment . Results : Vitamin D3 therapy in PCOS patients , increased serum vitamin D ( 7.00±2.80 to 22.9±6.14 ng/ml ) , decreased serum total cholesterol ( 196.6±32.8 to 179.1±34.1 mg/dl ) , triglyceride ( 156.8±73.0 to 130.5±56.5 mg/dl ) , and VLDL ( 31.4±14.6 to 26.1 ±11.3 mg/dl ) levels significantly ( p<0.05 ) , but it did not affect serum HDL-cholesterol , LDL-cholesterol , APO-AI , and hs-CRP concentrations . There was no change in variables in the placebo group . Conclusions : Our study showed that vitamin D3 therapy had beneficial effects on some CVD risk factors in PCOS patients with vitamin D deficiency . The trial was registered at I RCT .ir ( I RCT 138904113140N2 ) BACKGROUND AND AIMS Low vitamin D levels are associated with increased incidence of future cardiovascular events and are common in stroke patients . We tested whether vitamin D supplementation could reduce blood pressure and improve markers of vascular health in patients who had previously suffered a stroke . METHODS AND RESULTS R and omised , placebo-controlled , double-blind trial . Community-dwelling patients with a history of stroke and baseline 25-hydroxyvitamin D levels < 75 nmol/L received 100,000 units of oral vitamin D2 or placebo at baseline . Office and 24 h blood pressure , endothelial function measured by flow-mediated dilatation of the brachial artery , cholesterol , oxidised low density lipoprotein , B-type natriuretic peptide and heart rate turbulence were measured at baseline , 8 weeks and 16 weeks . 58 patients were r and omised . Mean age was 67 years , mean baseline blood pressure 128/72 mmHg , mean baseline 25-hydroxyvitamin D level was 38 nmol/L.  Serum 25-hydroxyvitamin D levels were higher in the intervention group at 8 weeks compared to placebo ( 54 vs 42 nmol/L , P = 0.002 ) and remained higher at 16 weeks . Office systolic and diastolic blood pressure showed no significant change between groups at 8 weeks ( systolic 126.1 vs 131.3 mmHg ; adjusted P = 0.97 ) ; ( diastolic 73.1 vs 74.9 mmHg , adjusted P = 0.15 ) . Flow mediated dilatation was significantly higher in the intervention group at 8 weeks ( 6.9 % vs 3.7 % , adjusted P = 0.007 ) but was not significantly different at 16 weeks . CONCLUSIONS High dose oral vitamin D supplementation did not improve blood pressure but produced short-term improvement in endothelial function in stroke patients with well-controlled baseline blood pressure . CLINICAL TRIALS REGISTRATION IS RCT N28737567 Unfavorable metabolic profiles and oxidative stress in pregnancy are associated with several complications . This study was conducted to determine the effects of vitamin D supplementation on serum concentrations of high-sensitivity C-reactive protein ( hs-CRP ) , metabolic profiles , and biomarkers of oxidative stress in healthy pregnant women . This r and omized , double-blind , placebo-controlled clinical trial was conducted in 48 pregnant women aged 18 - 40 y old at 25 wk of gestation . Participants were r and omly assigned to receive either 400 IU/d cholecalciferol supplements ( n = 24 ) or placebo ( n = 24 ) for 9 wk . Fasting blood sample s were taken at study baseline and after 9 wk of intervention to quantify serum concentrations of hs-CRP , lipid concentrations , insulin , and biomarkers of oxidative stress . After 9 wk of intervention , the increases in serum 25-hydroxyvitamin D and calcium concentrations were greater in the vitamin D group ( + 3.7 μg/L and + 0.20 mg/dL , respectively ) than in the placebo group ( -1.2 μg/L and -0.12 mg/dL , respectively ; P < 0.001 for both ) . Vitamin D supplementation result ed in a significant decrease in serum hs-CRP ( vitamin D vs. placebo groups : -1.41 vs. + 1.50 μg/mL ; P-interaction = 0.01 ) and insulin concentrations ( vitamin D vs. placebo groups : -1.0 vs. + 2.6 μIU/mL ; P-interaction = 0.04 ) and a significant increase in the Quantitative Insulin Sensitivity Check Index score ( vitamin D vs. placebo groups : + 0.02 vs. -0.02 ; P-interaction = 0.006 ) , plasma total antioxidant capacity ( vitamin D vs. placebo groups : + 152 vs. -20 mmol/L ; P-interaction = 0.002 ) , and total glutathione concentrations ( vitamin D vs. placebo groups : + 205 vs. -32 μmol/L ; P-interaction = 0.02 ) compared with placebo . Intake of vitamin D supplements led to a significant decrease in fasting plasma glucose ( vitamin D vs. placebo groups : -0.65 vs. -0.12 mmol/L ; P-interaction = 0.01 ) , systolic blood pressure ( vitamin D vs. placebo groups : -0.2 vs. + 5.5 mm Hg ; P-interaction = 0.01 ) , and diastolic blood pressure ( vitamin D vs. placebo groups : -0.4 vs. + 3.1 mm Hg ; P-interaction = 0.01 ) compared with placebo . In conclusion , vitamin D supplementation for 9 wk among pregnant women has beneficial effects on metabolic status IMPORTANCE Observational data link low 25-hydroxyvitamin D levels to both prevalent blood pressure and incident hypertension . No clinical trial has yet examined the effect of vitamin D supplementation in isolated systolic hypertension , the most common pattern of hypertension in older people . OBJECTIVE To test whether high-dose , intermittent cholecalciferol supplementation lowers blood pressure in older patients with isolated systolic hypertension . DESIGN Parallel group , double-blind , placebo-controlled  r and omized trial . SETTING Primary care clinics and hospital clinics . PARTICIPANTS Patients 70 years and older with isolated systolic hypertension ( supine systolic blood pressure > 140 mm Hg and supine diastolic blood pressure < 90 mm Hg ) and baseline 25-hydroxyvitamin D levels less than 30 ng/mL were r and omized into the trial from June 1 , 2009 , through May 31 , 2011 . INTERVENTIONS A total of 100,000 U of oral cholecalciferol or matching placebo every 3 months for 1 year . MAIN OUTCOMES AND MEASURES Difference in office blood pressure , 24-hour blood pressure , arterial stiffness , endothelial function , cholesterol level , insulin resistance , and b-type natriuretic peptide level during 12 months . RESULTS A total of 159 participants were r and omized ( mean age , 77 years ) .  Mean baseline office systolic blood pressure was 163/78 mm Hg . Mean baseline 25-hydroxyvitamin D level was 18 ng/mL. 25-Hydroxyvitamin D levels increased in the treatment group compared with the placebo group ( + 8 ng/mL at 1 year , P < .001 ) . No significant treatment effect was seen for mean ( 95 % CI ) office blood pressure ( −1 [ −6 to 4]/−2 [ −4 to 1 ] mm Hg at 3 months and 1 [ −2 to 4]/0 [ −2 to 2 ] mm Hg overall treatment effect ) . No significant treatment effect was evident for any of the secondary outcomes ( 24-hour blood pressure , arterial stiffness , endothelial function , cholesterol level , glucose level , and walking distance ) . There was no excess of adverse events in the treatment group , and the total number of falls was nonsignificantly lower in the group receiving vitamin D ( 36 vs 46 , P = .24 ) . CONCLUSIONS AND RELEVANCE Vitamin D supplementation did not improve blood pressure or markers of vascular health in older patients with isolated systolic hypertension . TRIAL REGISTRATION is rct n.org Identifier : IS RCT N92186858 BACKGROUND Low vitamin D levels are common , and are associated with a higher incidence of future vascular events . We tested whether vitamin D supplementation could improve endothelial function and other markers of vascular function in patients with a history of myocardial infa rct ion . METHODS Parallel group , placebo-controlled , double-blind r and omised trial . Patients with a history of myocardial infa rct ion were r and omised to receive 100,000 units of oral vitamin D3 or placebo at baseline , 2 months and 4 months . Outcomes were measured at baseline , 2 and 6 months . Reactive hyperaemia index on fingertip plethysmography was the primary outcome . Secondary outcome measures included blood pressure , cholesterol , C-reactive protein , von Willebr and factor , tumour necrosis factor alpha , E-selectin , B-type natriuretic peptide , thrombomodulin and 25-hydroxyvitamin D levels . RESULTS 75 patients were r and omised , mean age 66 years . 74/75 ( 99 % ) completed 6 month follow-up . 25 hydroxyvitamin D levels increased in the intervention group relative to placebo ( + 13 vs + 1 nmol/L , p=0.04 ) . There was no between-group difference in change in reactive hyperaemia index between baseline and 6 months ( -0.18 vs -0.07 , p=0.40 ) . Of the secondary outcomes , only C-reactive protein showed a significant decline in the intervention arm relative to placebo at 6 months ( -1.3 vs 2.0mg/L , p=0.03 ) . Systolic blood pressure ( + 1.4 vs + 2.3 mmHg , p=0.79 ) , diastolic blood pressure ( + 2.0 vs + 0.8 mmHg , p=0.54 ) and total cholesterol ( + 0.26 vs + 0.24 mmol/L , p=0.88 ) showed no between-group difference at 6 months . CONCLUSIONS Supplementation with vitamin D did not improve markers of vascular function in patients with a history of myocardial infa rct ion BACKGROUND AND OBJECTIVES Observational studies suggest that calciferol supplementation may improve laboratory and patient-level outcomes of hemodialysis patients with reduced 25-hydroxyvitamin D [ 25(OH)D ] levels . This r and omized controlled trial examined effects of cholecalciferol supplementation in patients on hemodialysis . DESIGN , SETTING , PARTICIPANTS , & MEASUREMENTS Sixty patients with 25(OH)D levels ≤24 ng/ml ( ≤60 nmol/L ) were r and omized to receive 50,000 IU oral cholecalciferol or placebo , once weekly for 8 weeks and then monthly for 4 months . At baseline ( autumn 2011 ) and 6 months , testing evaluated muscle strength , functional capacity , laboratory parameters , pulse wave velocity ( PWV ) , and health-related quality of life ( HRQOL ) using the Kidney Disease Quality of Life-36 survey . RESULTS Patients were well matched by treatment allocation . Median age was 62 years ( range , 20 - 86 ) , 52 % were women , 55 % had a history of diabetes , and mean serum 25(OH)D was 17±5 ng/ml ( 43±13 nmol/L ) . Patients were assessed over 6 months by repeated- measures ANOVA . Patients allocated to cholecalciferol had significantly higher values of 25(OH)D ( P<0.001 ) , 1,25-dihydroxyvitamin D ( P=0.04 ) , and tartrate-resistant acid phosphatase-5b ) ( P=0.04 ) and a greater reduction in phosphorus values ( P=0.03 ) than placebo-treated  patients Values of serum calcium , intact parathyroid hormone , and episodes of hypercalcemia and hyperphosphatemia did not differ significantly between the groups . No significant differences were detected in muscle strength , functional capacity , PWV , or HRQOL . CONCLUSIONS In this r and omized controlled trial , patients supplemented with cholecalciferol  had higher 25(OH)D , 1,25-dihydroxyvitamin D , and tartrate-resistant acid phosphatase-5b levels , without increased calcium or phosphorus values . However , no effects were detected in muscle strength , functional capacity , PWV , or HRQOL Patients with cystic fibrosis ( CF ) suffer from chronic lung infection and inflammation leading to respiratory failure . Vitamin D deficiency is common in patients with CF , and correction of vitamin D deficiency may improve innate immunity and reduce inflammation in patients with CF . We conducted a double-blinded , placebo-controlled , r and omized clinical trial of high-dose vitamin D to assess the impact of vitamin D therapy on antimicrobial peptide concentrations and markers of inflammation . We r and omized 30 adults with CF hospitalized with a pulmonary exacerbation to 250 000 IU of cholecalciferol or placebo  , and evaluated changes in plasma concentrations of inflammatory markers and the antimicrobial peptide LL-37 at baseline and 12 weeks post intervention . In the vitamin D group , there was a 50.4 % reduction in tumor necrosis factor-α ( TNF-α ) at 12 weeks ( P<0.01 ) , and there was a trend for a 64.5 % reduction in interleukin-6 ( IL-6 ) ( P=0.09 ) . There were no significant changes in IL-1β , IL-8 , IL-10 , IL-18BP and NGAL ( neutrophil gelatinase-associated lipocalin ) . We conclude that a large bolus dose of vitamin D is associated with reductions in two inflammatory cytokines , IL-6 and TNF-α . This study supports the concept that vitamin D may help regulate inflammation in CF , and that further research is needed to eluci date the potential mechanisms involved and the impact on clinical outcomes OBJECTIVE To study the effect of estrogen and progesterone on the expression of dihydroxyvitamin D receptor ( VDR ) mRNA in the liver of ovariectomized rats . METHODS Twenty-five adult female SD rats were r and omly divided , with equal numbers , into sham-operated group ( sham ) , ovariectomized group ( OVX ) , ovariectomized group with estrogen treatment ( OVX+E ) , ovariectomized group with progesterone treatment ( OVX+P ) and ovariectomized group with both estrogen and progesterone treatment ( OVX+E+P ) . After 3 months and a half of feeding , all animals were killed to assess VDR mRNA by way of reverse transcriptase-PCR ( RT-PCR ) . RESULTS RT-PCR revealed marked increase in the b and intensity corresponding to VDR mRNA product in Sham , OVX+E , and OVX+E+P groups . CONCLUSION Estrogen may increase the transcription level of VDR gene in the liver of ovariectomized rats BACKGROUND Suboptimal vitamin D status is associated with endothelial dysfunction and an increased risk of cardiovascular diseases but it is unclear whether vitamin D supplementation is beneficial . The aim was to investigate the effect of vitamin D supplementation on endothelial function in patients with type 2 diabetes mellitus ( DM ) . METHODS In a double-blind , placebo-controlled trial , we r and omized 100 type 2 DM patients to vitamin D supplement  ( 5000 IU/day , n = 50 ) or placebo ( controls , n = 50 ) for 12 weeks . Assessment of vascular function with brachial artery flow-mediated dilatation ( FMD ) , circulating levels of endothelial progenitor cells ( EPCs ) and brachial-ankle pulse wave velocity , and metabolic parameter , high-sensitivity C-reactive protein ( hsCRP ) and oxidative stress markers were performed before and after the supplementation . RESULTS After 12 weeks , vitamin D treated patients had significant increases in serum 25-hydroxyvitamin D [ 25(OH)D ] concentration ( treatment effect 34.7 ng/mL , 95 % CI 26.4 - 42.9 , P < 0.001 ) and serum ionized calcium ( treatment effect 0.037 mmol/L , 95 % CI 0.007 - 0.067 , P = 0.018 ) ; decreased serum parathyroid hormone concentration ( treatment effect -0.55 pmol/L , 95 % CI -1.08 to -0.02 , P = 0.042 ) compared to patients who received placebo . Nevertheless , vitamin D supplementation did not improve vascular function as determined by FMD , circulating EPC count or baPWV ( all P > 0.05 ) . Furthermore , hsCRP , oxidative stress markers , low- and high-density lipoprotein and glycated hemoglobin were also similar between two groups ( all P > 0.05 ) . CONCLUSION In patients with type 2 DM , 12 weeks oral supplementation of vitamin D did not significantly affect vascular function or serum biomarkers of inflammation and oxidative stress . CLINICAL TRIAL NUMBER HKCTR-867 , www.hk clinical trials.com BACKGROUND Hypovitaminosis D is common in chronic kidney disease ( CKD ) . Effects of 25-hydroxyvitamin D replenishment in CKD are not well described . METHODS An 8-week r and omized , placebo-controlled , double-blind parallel intervention study was conducted in haemodialysis ( HD ) and non-HD CKD patients . Treatment consisted of 40,000 IU of cholecalciferol orally per week . Plasma 25-hydroxyvitamin D ( 25-OHD ) , plasma 1,25-dihydroxyvitamin D ( 1,25-diOHD ) , plasma parathyroid hormone ( PTH ) , serum phosphate , ionized serum calcium and serum fibroblast growth factor 23 ( FGF-23 ) were analysed . We also investigated biomarkers related to cardiovascular disease ( plasma D-dimer , plasma fibrinogen , plasma von Willebr and factor antigen and activity , plasma interleukin 6 , plasma C-reactive protein , blood pressure , aortic augmentation index , aortic pulse wave velocity and 24-h urinary protein loss ) . Objective and subjective health variables were assessed ( muscle function tests , visual analogue scores and Health Assessment Question naire ) . RESULTS Fifty-two CKD patients with 25-OHD < 50 nmol/L at screening were included .  Cholecalciferol supplementation led to a significant increase to a median of 155 nmol/L 25-OHD ( interquartile range 137 - 173 nmol/L ) in treated patients ( n = 25 , P < 0.001 ) . In non-HD patients , we saw a significant increase in 1,25-diOHD ( n = 13 , P < 0.01 ) and a lowering of PTH ( n = 13 , P < 0.001 ) . This was not observed in HD patients .  Cholecalciferol supplementation caused a significant increase in serum calcium and FGF-23 . CONCLUSIONS 25-OHD replenishment was effectively obtained with the employed cholecalciferol dosing . In non-HD patients , it had favourable effects on 1,25-diOHD and PTH .  Vitamin D-supplemented patients must be monitored for hypercalcaemia . The present study could not identify significant pleiotropic effects of 25-OHD replenishment BACKGROUND A growing body of evidence has linked vitamin D deficiency to increased risk of cardiovascular disease . Vitamin D deficiency is also more common in African Americans for whom an increased cardiovascular disease risk exists . This study sought to test the hypothesis that 16 weeks of 60,000 IU monthly supplementation of oral vitamin D(3 ) would improve flow-mediated dilation ( FMD ) in African Americans , whereas no change would be observed in the placebo group . METHODS A r and omized , double-blind , placebo-controlled clinical trial was conducted . Fifty-seven African-American adults were r and omly assigned to either the placebo group or vitamin D group . RESULTS Following 16 weeks of placebo ( n = 23 ; mean age 31 ± 2 years ) or 60,000 IU monthly oral vitamin D(3 ) ( n = 22 ; mean age 29 ± 2 years ) , serum concentrations of 25-hydroxyvitamin D ( 25(OH)D ) increased from 38.2 ± 3.0 to 48.7 ± 3.2 nmol/l and 34.3 ± 2.2 to 100.9 ± 6.6 nmol/l , respectively . No changes in serum parathyroid hormone ( PTH ) , serum calcium , or urine calcium/creatinine were observed following either treatment . Following 16 weeks of treatment , significant improvements in FMD were only observed in the vitamin D group ( 1.8 ± 1.3 % ) , whereas the placebo group had no change ( -1.3 ± 0.6 % ) . Similarly , the vitamin D group exhibited an increase in absolute change in diameter ( 0.005 ± 0.004 cm ) and FMD/shear ( 0.08 ± 0.04 % /s(-1 ) , area under the curve ( AUC ) × 10(3 ) ) following treatment , whereas no change ( -0.005 ± 0.002 cm and -0.02 ± 0.02 % /s(-1 ) , AUC , respectively ) was observed following placebo . CONCLUSION Supplementation of 60,000 IU monthly oral vitamin D(3 ) ( ~2,000 IU/day ) for 16 weeks is effective at improving vascular endothelial function in African-American adults BACKGROUND & AIMS Vitamin D supplementation has the potential to alleviate the cardiovascular damage in diabetic patients . The present study was design ed to evaluate long term impact of high doses of vitamin D on arterial properties , glucose homeostasis , adiponectin and leptin in patients with type 2 diabetes mellitus . METHODS AND RESULTS In r and omized , placebo-controlled study 47 diabetic patients were assigned into two groups : Group 1 received oral daily supplementation with vitamin D at a dose of 1000 U/day for 12 months . Group 2 received matching placebo capsules . Blood sampling for metabolic parameters , including fasting glucose , lipid profile , HbA1C , insulin , hs-CRP , 25 OH Vit D , adiponectin and leptin was performed at baseline and at the end of the study . Insulin resistance was assessed by homeostasis model assessment ( HOMA-IR ) . Central aortic augmentation index ( AI ) was evaluated using SphygmoCor . RESULTS The two groups were similar at baseline in terms of hemodynamic parameters . After 12 months , AI decreased significantly during the treatment period in patients received vitamin D ( p < 0.0001 ) and did not change in placebo group . Glucose homeostasis parameters , leptin as well as leptin adiponectin ratio did not change in both groups . 25 OH Vit D level significantly increased ( p = 0.022 ) and circulating adiponectin marginally increased ( p = 0.065 ) during 12 month treatment period in active treatment and did not change in placebo group . CONCLUSIONS High doses of  vitamin D supplementation in diabetic patients was associated with significant decrease in AI during one year treatment . This beneficial vascular effect was not associated with improvement in glucose homeostasis parameters CONTEXT In humans , few studies have compared the potencies of ergocalciferol and cholecalciferol in improving and maintaining vitamin D status . OBJECTIVE Our objective was to evaluate the effects of a single very large dose of both calciferols on serum changes of 25-hydroxyvitamin D [ 25(OH)D ] , 1,25-dihydroxyvitamin D [ 1,25(OH)(2)D ] , ionized calcium , and parathyroid hormone ( PTH ) at baseline , and at 3 , 7 , 30 , and 60 d. DESIGN This was a prospect i ve r and omized intervention study . SETTING The study was performed in a nursing home residence . PARTICIPANTS A total of 32 elderly female patients ( age range 66 - 97 yr ) , with vitamin D deficiency was included in the study . INTERVENTION Participants were r and omized into four groups of eight to receive a single dose of 300,000 IU ergocalciferol or cholecalciferol by oral ( os ) or i m route . RESULTS 25(OH)D levels sharply increased at d 3 only when vitamins were given os . The 30-d basal difference in serum 25(OH)D was significantly greater after cholecalciferol os administration ( 47.8 + /- 7.3 ng/ml ) compared with other forms ( D(3 ) i m : 15.9 + /- 11.3 ; D(2 ) os : 17.3 + /- 4.7 ; D(2 ) i m : 5 + /- 4.4 ; all P < 0.001 ) . The area under the curve ( AUC ) of the serum 25(OH)D against time ( AUC(60 ) ) was : D(3 ) os , 3193 + /- 759 ng x d/ml vs. D(2 ) os , 1820 + /- 512 , P < 0.001 ; and D(3 ) i m , 1361 + /- 492 vs. D(2 ) i m , 728 + /- 195 , P < 0.01 . 25(OH)D significantly influences PTH levels at 3 ( P < 0.03 ) , 7 ( P < 0.01 ) , 30 ( P < 0.01 ) , and 60 d ( P < 0.05 ) . At 60 d , the form of vitamin ( cholecalciferol ) significantly lowers PTH levels ( P = 0.037 ) . CONCLUSIONS Cholecalciferol is almost twice as potent as ergocalciferol in increasing serum 25(OH)D , when administered either by mouth or i m . 25(OH)D plays a role in modulating serum PTH AIMS To test whether a single large dose of vitamin D2 can improve endothelial function in patients with Type 2 diabetes mellitus and low serum 25-hydroxyvitamin D levels . METHODS Double-blind , parallel group , placebo-controlled r and omized trial . A single dose of 100,000 IU vitamin D2 or placebo was administered to patients with Type 2 diabetes over the winter , when levels of circulating 25-hydroxyvitamin D were likely to be lowest . Patients were enrolled if their baseline 25-hydroxyvitamin D level was < 50 nmol/l .  Endothelial function and blood pressure were measured and fasting blood sample s were taken at baseline and 8 weeks after administration of vitamin D. RESULTS Forty-nine per cent of subjects screened had 25-hydroxyvitamin D levels < 50 nmol/l . Thirty-four subjects completed the study , with a mean age of 64 years and a baseline 25-hydroxyvitamin D level of 38.3 nmol/l .  Vitamin D supplementation  increased 25-hydroxyvitamin D levels by 15.3 nmol/l relative to placebo and significantly improved flow mediated vasodilatation ( FMD ) of the brachial artery by 2.3 % . The improvement in FMD remained significant after adjusting for changes in blood pressure .  Vitamin D supplementation significantly decreased systolic blood pressure by 14 mmHg compared with placebo ; this did not correlate with change in FMD . CONCLUSIONS Vitamin D insufficiency is common in patients with Type 2 diabetes during winter in Scotl and . A single large dose of oral vitamin D2 improves endothelial function in patients with Type 2 diabetes and vitamin D insufficiency OBJECTIVE Apart from its role in bone metabolism , vitamin D may also influence cardiovascular disease . The objective of this study was : ( 1 ) to determine the effect of a single , oral , high-dose vitamin D supplementation on endothelial function and arterial stiffness in patients with peripheral arterial disease ( PAD ) and ( 2 ) to investigate the impact of this supplementation on coagulation and inflammation parameters . METHODS In this double-blind , placebo-controlled , interventional pilot study , we screened 76 Caucasian patients with PAD for vitamin D deficiency . Sixty-two were r and omised to receive a single , oral supplementation of 100,000 IU vitamin D3 or placebo . At baseline and after 1 month , we measured serum vitamin D and parathormone levels , and surrogate parameters for cardiovascular disease . RESULTS Sixty-five of 76 patients ( 86 % ) had low 25-hydroxyvitamin D levels ( < 30 ng ml(-1 ) ) ; of those , 62 agreed to participate in the study . At baseline , only parathormone was related to vitamin D. In supplemented patients , vitamin D levels increased from 16.3 ± 6.7 to 24.3 ± 6.2 ng ml(-1 ) ( P < 0.001 ) , with wide variations between single patients ; in the placebo group vitamin levels did not change . Seasonal factors accounted for a decrease of vitamin D levels by 8 ng ml(-1 ) between summer and winter . After 1 month , none of the measured parameters was influenced by vitamin substitution . CONCLUSION In this pilot study , most patients with PAD were vitamin D deficient . Vitamin D supplementation  increased serum 25-hydroxyvitamin D without influencing endothelial function , arterial stiffness , coagulation and inflammation parameters , although the study was underpowered for definite conclusions Adequate vitamin D levels may promote cardiovascular health by improving endothelial function and down-regulating inflammation . The objective of this pilot trial was to investigate the effects of vitamin D repletion on endothelial function and inflammation in patients with coronary artery disease ( CAD ) . Using a double-blind placebo wait-list control design , 90 subjects with CAD and vitamin D deficiency ( < 20 ng/ml ) were r and omized 1:1 to 50,000 IU of oral ergocalciferol or placebo weekly for 12 weeks . Endothelial function ( reactive hyperemia peripheral arterial tonometry , RH-PAT ) , circulating adhesion molecules , and pro-inflammatory cytokines were measured at baseline and 12 weeks . The median increase in serum 25-vitamin D from baseline was 26 ± 17 ng/ml in the active group and 4 ± 8 ng/ml in the placebo group ( between-group difference = 22 ng/ml , p < 0.001 ) . The median within-subject change in RH-PAT score was 0.13 ± 0.73 with active treatment and −0.04 ± 0.63 with placebo ( between-group difference = 0.17 , p = 0.44 ) . Within-group and between-group differences in intercellular adhesion molecule levels were greater with placebo ( between-group difference = 6 ng/ml , p = 0.048 ) . Vascular cell adhesion molecule levels decreased in both groups by a similar magnitude ( median difference between groups = 8.5 ng/ml , p = 0.79 ) . There was no difference between groups in magnitude of reduction in interleukin (IL)-12 ( −8.6 ng/ml , p = 0.72 ) and interferon-gamma ( 0.52 ng/ml , p = 0.88 ) . No significant differences in blood pressure , e-selectin , high-sensitivity c-reactive protein , IL-6 or the chemokine CXCL-10 were found with treatment . In conclusion , repleting vitamin D levels in subjects with CAD failed to demonstrate any benefits on surrogate markers of cardiovascular health . These results question the role of vitamin D supplementation in modifying cardiovascular disease
target: Evidence from the studies included in this systematic review did not demonstrate that vitamin D supplementation in adults , results in an improvement in circulating inflammatory and endothelial function biomarkers/parameters .
  This systematic review does not therefore support the use of vitamin D supplementation as a therapeutic or preventative measure for CVD in this respect
background: This systematic review aims to evaluate r and omised controlled trials ( RCTs ) investigating the effect of vitamin D supplementation on  endothelial function and inflammation in adults .