The effect of vitamin D on the lipid profile as a risk factor for coronary heart disease in postmenopausal women: a meta-analysis and systematic review of randomized controlled trials

Effects of green tea on lipid profile in overweight and obese women

The effect of green tea administration on serum lipids' concentrations remains unclear as various investigations, which have explored this topic, have produced conflicting results. Gender might be one of the factors influencing the impact of green tea on the lipid profile. Hence, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of green tea intake on the lipid profile in overweight and obese women. We searched five databases (Web of Science, SCOPUS, Embase, PubMed/Medline, and Google Scholar) using a combination of MeSH and non-MeSH terms. Results were expressed as weighted mean differences (WMDs) and 95% confidence intervals (CIs) and synthesized with a random-effects model. In total, 15 eligible RCTs with 16 arms (1818 participants) were included in the meta-analysis. The combined effect size revealed a significant reduction in total cholesterol (TC) (WMD: -4.45 mg/dl, 95% CI: -6.63, -2.27, P<0.001) and low-density lipoprotein cholesterol (LDL-C) (WMD: -4.49 mg/dl, 95% CI: -7.50 to -1.47, P=0.003) concentrations following green tea supplementation in overweight and/or obese women. In addition, a more pronounced reduction of triglyceride (TG) levels occurred when the baseline TG value was ≥150 mg/dL (WMD: -24.45 mg/dL, 95% CI: -40.63 to -8.26, P=0.003). Moreover, a significant decrease in TG concentrations occurred in RCTs conducted on overweight subjects (BMI: 25-29.99 kg/m2) (WMD: -5.88 mg/dl, 95% CI: -10.76 to -0.99, P=0.01). In the subgroup analyses based on the study population, a notable increase in high-density lipoprotein cholesterol (HDL-C) values was observed in obese individuals (>30 kg/m2) (WMD: 2.63 mg/dl, 95% CI: 0.10 to 5.16, P=0.041). Consumption of green tea causes a reduction in LDL-C and TC concentrations in overweight and obese women. The decline in TG levels was notable particularly in overweight patients with hypertriglyceridemia at baseline. In addition, a significant increase in HDL-C was detected in obese subjects following intake of green tea.

The interaction between lipid and vitamin D3 impacts lipid metabolism and innate immunity in Chinese mitten crabs Eriocheir sinensis

As a fat-soluble vitamin, vitamin D3 relies on fat to perform its biological function, affecting lipid metabolism and innate immunity. This study used different percentages of lipid and vitamin D3 diets to evaluate the synergistic effects on the growth, lipid metabolism and immunity of juvenile Eriocheir sinensis (5.83 ± 0.01 g) for 56 days, including low lipid (LL, 1.5%) and normal lipid (NL, 7.5%) and three levels of vitamin D3: low (LVD, 0 IU/kg), medium (MVD, 9000 IU/kg) and high (HVD, 27,000, IU/kg). The synergistic effect of lipid and vitamin D3 was not significant on growth but significant on ash content, total protein, hepatopancreas lipid content, hemolymph 1α,25-hydroxy vitamin D3 [1α,25(OH)2D3] content, hepatopancreas lipolysis and synthesis genes. Crabs fed normal lipid (7.5%) and medium vitamin D3 (9000 IU/kg) had the highest hepatopancreas index, hemolymph 1α,25(OH)2D3 content, antibacterial ability, immune-related genes and hepatopancreatic lipid synthesis genes expression, but down-regulated the lipolysis genes expression. In contrast, crabs fed diets with low lipid percentage (1.5%) had low growth performance, hemolymph 1α,25(OH)2D3, mRNA levels of lipid synthesis genes, antibacterial ability and immune-related gene expression. At the 1.5% lipid level, excessive or insufficient vitamin D3 supplementation led to the obstruction of ash and protein deposition, reduced growth and molting, aggravated the reduction in antioxidant capacity, hindered antimicrobial peptide gene expression and reduced innate immunity, and resulted in abnormal lipid accumulation and the risk of oxidative stress. This study suggests that diets' lipid and vitamin D3 percentage can enhance antioxidant capacity, lipid metabolism and innate immunity in E. sinensis. A low lipid diet can cause growth retardation, reduce antioxidant capacity and innate immunity, and enhance lipid metabolism disorder.

The Correlation Between Vitamin D Levels and the Glycemic Marker HbA1c and Lipid Profile in Patients With Type 2 Diabetes Mellitus: A Study at the King Saud Medical City, Riyadh

Background and objective Vitamin D, a fat-soluble vitamin also called the sunshine vitamin, is produced in plants, and animals when exposed to sunlight. It plays a crucial role in musculoskeletal development, immune system regulation, and glucose metabolism, thereby reducing the risk of diabetes. This study aimed to investigate the association of vitamin D levels with glycemic control markers [glycated hemoglobin (HbA1c)] and lipid profile, as well as sociodemographic factors and comorbidities. Methodology A cross-sectional study was conducted at the King Saud Medical City in Riyadh, Saudi Arabia, among adult diabetic patients aged 20 years and above. The sociodemographic characteristics, vitamin D levels, HbA1c, and lipid profiles of 472 participants were studied. Data were analyzed using SPSS Statistics version 27 (IBM Corp., Armonk, NY). Results The majority of the participants were women (n=296, 62.7%); the mean age of the cohort was 56.5 ±13.13 years. Most participants were Saudi nationals (n=361, 76.5%). Lab tests revealed vitamin D deficiency (71.41 ±36.88 nmol/l) and elevated HbA1c (9.49 ±9.85%) in the cohort. Low-density lipoprotein (LDL) cholesterol levels were higher than normal (2.71 ±4.26 mmol/l), while high-density lipoprotein (HDL) was slightly lower (1.23 ±0.39 mmol/l). Bivariate correlations showed weak negative and positive associations between vitamin D and HbA1c (r=-0.093, p<0.05) and HDL (r=0.114, p<0.05), respectively. HbA1c correlated positively with triglycerides (r=0.168, p<0.01). Conclusions We found an association between deficiency of vitamin D and levels of HbA1c and lipid profile in type 2 diabetes patients. The association was marked by low vitamin D levels and characterized by high HbA1c, LDL cholesterol, and lipid profile. Elevated HbA1c, LDL cholesterol, and triglyceride levels suggested vitamin D's role in lipid homeostasis. Variations in biomarker levels across sociodemographic factors highlight the need for personalized interventions for diabetes prevention and management.

Red Yeast Rice and Statin Therapy in Patients with Hypercholesterolemia and the Comorbidities: A Retrospective Cohort Study on Lipid-Lowering Effects and Cardiovascular Outcomes

Red yeast rice (RYR) is known for its lipid-lowering effects in patients with hypercholesterolemia; however, its comparative efficacy with statins and risk reduction remains uncertain. This retrospective study analyzed data from 337,104 patients with hyperlipidemia in the Chang Gung Research Database cohort, spanning from January 2016 to December 2021. Exclusion criteria were applied to ensure data completeness and compliance, including an age limit of [Formula: see text] years, absence of RYR or statin treatment, and a treatment duration of [Formula: see text] days. Propensity score matching was employed to minimize bias based on baseline factors, with one patient matching with four patients in the comparison group. The study encompassed a total of 5,984 adult hyperlipidemic patients, with 1,197 in the RYR group and 4,787 in the statin group. The patients were also stratified into statin ([Formula: see text]) or combined use ([Formula: see text]) groups for further comparison. Following one year of treatment, both the RYR and statin groups exhibited reductions in total cholesterol and triglyceride levels. Most biochemical parameters showed no significant differences, except for elevated glutamic oxaloacetic transaminase levels in the RYR group ([Formula: see text]) and increased glycohemoglobin levels in the statin group at the three-month mark ([Formula: see text]). In patients with comorbid diabetes, hypertension, kidney, or liver diseases, RYR and statins demonstrated comparable risks for emergency room (ER) visits, stroke, and myocardial infarction (MI). However, the combination of RYR and statins was associated with reduced stroke-related hospitalizations in patients with diabetes, hypertension, and kidney disease, as well as decreased MI-related hospitalizations in patients with hypertension and kidney disease (all [Formula: see text]). In conclusion, both RYR and statins effectively lower blood lipid levels and mitigate related complications. Combining these therapies may lead to fewer ER visits, reduced stroke frequency, and fewer MI hospitalizations in hypertensive and kidney disease patients, and they decreased all-cause mortality in the kidney disease population. Further research on combined therapy is warranted.

The Effects of Vitamin D Supplementation on C-Reactive Protein and Systolic and Diastolic Blood Pressure in Postmenopausal Women: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

BACKGROUND

An inverse relationship between vitamin D supplementation and C-reactive protein (CRP) and hypertension has been reported, mostly through observational data. This inverse relationship, however, has not been confirmed in randomized controlled trials (RCTs). A meta-analysis of RCTs is needed to provide more robust evidence.

OBJECTIVE

This systematic review of RCTs was conducted to assess the effect of vitamin D supplementation on CRP, systolic blood pressure (SBP), and diastolic blood pressure (DBP) in postmenopausal women.

METHODS

Four databases (PubMed, Web of Science, Embase, and Scopus) were systemically searched to identify relevant RCTs published in international scientific journals up to January 2023. Changes from baseline and SDs of CRP, SBP, and DBP were compared between postmenopausal women who received vitamin D supplementation and those who did not (controls). These parameters were applied to compute the overall effect sizes using the random-effects model. Data were summarized as mean difference (MD) with 95% CI. Heterogeneity among arms was scrutinized using the Cochrane's Q test and I2 statistic. Publication bias was judged by means of funnel plots and Egger's test.

RESULTS

Seven studies with 6 arms on CRP, 6 arms on SBP, and 6 arms on DBP were included in the meta-analysis. Combined effect sizes suggested a significant effect of vitamin D supplementation on CRP (MD = -0.65 mg/L; 95% CI -0.93 to -0.37 mg/L; P < .001). In addition, CRP concentrations were significantly reduced after vitamin D supplementation in studies with a duration of more than 3 months (MD = -0.91 mg/L; 95% CI -1.37 to -0.45 mg/L; P < .001) and studies involving doses of ≤1,000 IU/d (MD = -2.10 mg/L; 95% CI -2.51 to -1.68 mg/L; P < .001). Vitamin D supplementation did not reduce SBP significantly (MD = -1.06 mm Hg; 95% CI -2.43 to 0.30 mm Hg; P = .127) and DBP (MD = 0.003 mm Hg; 95% CI -0.86 to 0.86 mm Hg; P = .994) levels compared with control groups.

CONCLUSIONS

This meta-analysis concluded that vitamin D supplementation is associated with reduced CRP concentrations among postmenopausal women.

The impact of medroxyprogesterone acetate on lipid profiles in Women: A time and dose-response meta-analysis of randomized controlled trials

BACKGROUND

The effect of MPA on the lipid profile and CVD risk is still controversial; hence, this comprehensive dose-response meta-analysis of randomized controlled trials was conducted to assess the effect of MPA on lipid profiles in women.

METHODS

A comprehensive search was conducted in the following databases: Web of Science, Scopus, PubMed/Medline, and Embase, up to October 20, 2023. A random-effects meta-analysis approach based on the DerSimonian and Laird method was used to compute the combined estimates of the intervention's impact on the lipid profile.

RESULTS

35 eligible studies with 58 arms were included in our meta-analyses analysis. Combined effect sizes suggested a significant effect of MPA on total cholesterol (TC) levels (WMD: -3.43 mg/dL, 95 % CI: -5.38 to -1.48, p < 0.001), HDL-C levels (WMD: -3.34 mg/dL, 95 % CI: -3.77 to -2.91, p < 0.001), and triglyceride (TG) levels (WMD: -9.13 mg/dL, 95 % CI: -10.92 to -7.33, p < 0.001). The subgroup meta-analysis revealed a more substantial reduction in TC in studies with dosages > 2.5 mg/day (WMD: -4.10 mg/dL), mean participant age lower than 60 years (WMD: -3.80 mg/dL), mean BMI lower than 25 kg/m2 (WMD: -5.61 mg/dL), duration of intervention of 12 months or more (WMD: -3.98 mg/dL), and when the baseline TC value was equal to or greater than 200 mg/dL (WMD: -4.13 mg/dL).

CONCLUSIONS

The current meta-analysis showed a statistically significant decrease in TC, TG, and HDL-C levels and a non-significant increase in LDL-C levels after MPA administration in women.

The Effect of Vitamin D Supplementation on Lipid Profiles: an Umbrella Review of Meta-Analyses

According to published meta-analyses, vitamin D exerts different beneficial effects in preventing and controlling risk factors associated with noncommunicable chronic diseases; however, the results are still conflicting. The purpose of this umbrella meta-analysis was to investigate the effect of vitamin D supplementation on low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, total cholesterol (TC), and triglyceride (TG) as components of the lipid profile. PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews were systematically searched for meta-analyses of randomized controlled trials. The umbrella meta-analysis followed the PRISMA guidelines. The random-effects model was employed to estimate the overall effect size (ES). Overall, 25 meta-analyses were included. In the standardized mean difference analysis, vitamin D significantly decreased TG (ES: -0.15; 95% CI: -0.23, -0.08; P ≤ 0.001) and TC levels (ES: -0.17; 95% CI: -0.23, -0.11; P ≤ 0.001) and increased HDL levels (ES: 0.08; 95% CI: 0.01, 0.15; P = 0.025). In the weighted mean difference analysis, vitamin D significantly decreased only TG levels (ES: -4.63 mg/dL; 95% CI: -7.70, -1.57; P = 0.003). The present study supports that vitamin D supplementation could be considered a beneficial adjuvant therapy in managing lipid profile levels, especially in individuals with vitamin D deficiency. This systematic review was registered in PROSPERO as CRD42022306334.

Correlation between Serum 25-Hydroxyvitamin D Concentration, Monocyte-to-HDL Ratio and Acute Coronary Syndrome in Men with Chronic Coronary Syndrome-An Observational Study

Cardiovascular disease (CVD) continues to be the leading cause of death in European men. Atherosclerosis and its clinical consequence, chronic coronary syndrome (CCS), comprise two main elements: dysfunction of lipoprotein metabolism and an important inflammatory component that contributes to the development of complications, including acute coronary syndrome (ACS). Measures of both components are combined in a composite marker called monocyte-to-HDL ratio (MHR). Vitamin D was previously described to influence inflammation processes, and its deficiency influences CVD risk factors. This research describes the differences in MHR and total serum 25-hydroxyvitamin D (25(OH)D) concentration between male patients with different diagnoses of CCS and the correlation between 25(OH)D and MHR in this group. Significant differences were observed between ACS and CCS patients in 25(OH)D and MHR-the highest HDL and serum 25(OH)D concentrations were observed in patients with CCS, whereas the highest value of MHR was observed in patients with STEMI. A significant correlation was observed between 25(OH)D, HDL, and MHR. Due to the significant but small nominal difference in MHR values between groups of patients diagnosed with ACS and CCS, and the possible influence of age and hyperlipidemia status on the differences in vitamin D levels in these groups, this subject requires further well-designed research. The suggested bidirectional relationship between MHR and 25(OH)D and the role of MHR as a predictor of vitamin D status in the body also needs to be verified.

Bioinformatics and Systems Biology Approach to Identify the Pathogenetic Link between Heart Failure and Sarcopenia

Despite increasing evidence that patients with heart failure (HF) are susceptible to sarcopenia, the reason for the association is not well understood. The purpose of this study is to explore further the molecular mechanism of the occurrence of this complication. Gene expression datasets for HF (GSE57345) and Sarcopenia (GSE1428) were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified using 'edgeR' and "limma" packages of R, and their functions were analyzed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Protein-protein interaction (PPI) networks were constructed and visualized using Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape. Hub genes were selected using the plugin cytoHubba and validation with GSE76701 for HF and GSE136344 for Sarcopenia. The related pathways and molecular mechanisms of the hub genes were performed by Gene set enrichment analysis (GSEA). The statistical analyses were performed using R software. P < 0.05 was considered statistically significant. A total of 114 common DEGs were found. Pathways related to growth factor, Insulin secretion and cGMP-PKG were enriched in both HF and Sarcopenia. CYP27A1, KCNJ8, PIK3R5, TIMP2, CXCL12, KIT, and VCAM1 were found to be significant hub genes after validation, with GSEA emphasizing the importance of the hub genes in the regulation of the inflammatory response. Our study reveals that HF and Sarcopenia share common pathways and pathogenic mechanisms. These findings may suggest new directions for future research into the underlying pathogenesis.

Association of Vitamin D Genetic Risk Score with Noncommunicable Diseases: A Systematic Review

Background and Aims: The genetic risk score (GRS) is an important tool for estimating the total genetic contribution or susceptibility to a certain outcome of interest in an individual, taking into account their genetic risk alleles. This study aims to systematically review the association between the GRS of low vitamin D with different noncommunicable diseases/markers. Methods: The article was first registered in PROSPERO CRD42023406929. PubMed and Embase were searched from the time of inception until March 2023 to capture all the literature related to the vitamin D genetic risk score (vD-GRS) in association with noncommunicable diseases. This was performed using comprehensive search terms including "Genetic Risk Score" OR "Genetics risk assessment" OR "Genome-wide risk score" AND "Vitamin D" OR 25(HO)D OR "25-hydroxyvitamin D". Results: Eleven eligible studies were included in this study. Three studies reported a significant association between vD-GRS and metabolic parameters, including body fat percentage, body mass index, glycated hemoglobin, and fasting blood glucose. Moreover, colorectal cancer overall mortality and the risk of developing arterial fibrillation were also found to be associated with genetically deprived vitamin D levels. Conclusions: This systematic review highlights the genetic contribution of low-vitamin-D-risk single nucleotides polymorphisms (SNPs) as an accumulative factor associated with different non-communicable diseases/markers, including cancer mortality and the risk of developing obesity, type 2 diabetes, and cardiovascular diseases such as arterial fibrillation.

Vitamin D Levels Are Associated with Cardiovascular Disease Events but Not with Cardiovascular Disease or Overall Mortality: A Prospective Population-Based Study

(1) Background: A recent review concluded that there was no strong evidence for beneficial vitamin D effects on cardiovascular disease (CVD) risk, but whether individuals with vitamin D deficiency have a higher risk of CVD should be further studied. (2) Aims: We assessed the association between vitamin D levels and CVD events, CVD mortality, and overall mortality in a prospective population-based study in Lausanne, Switzerland. (3) Methods: A total of 5684 participants (53.6% women, 52.5 ± 10.7 years) were followed for a median of 14.4 years [interquartile range: 10.7-16.6]. Vitamin D blood levels were categorized as normal (≥75 nmol/L or 30 ng/mL), insufficient (50-74 nmol/L or 21-29 ng/mL), and deficient (<50 nmol/L or 20 ng/mL). (4) Results: In total, 568 cardiovascular events, 114 cardiovascular deaths, and 679 deaths occurred during follow-up. After multivariate analysis, vitamin D levels were negatively associated with CVD events: hazard ratio and (95% confidence interval) for a 10 nmol/L increase: 0.96 (0.92-0.99). However, no association was found for CVD [0.93 (0.84-1.04)] and overall mortality [0.98 (0.94-1.02)]. No associations were found between vitamin D categories and CVD events, 0.93 (0.71-1.22) and 1.14 (0.87-1.49); CVD deaths, 0.78 (0.41-1.50) and 1.10 (0.57-2.12); and overall mortality, 1.10 (0.82-1.48); and 1.17 (0.87-1.58) for insufficiency and deficiency, respectively. After excluding participants taking vitamin D supplements, similar results were obtained. (5) Conclusion: In this prospective population-based study, vitamin D levels were inversely associated with CVD events but not with CVD or overall mortality.

The Effects of Vitamin D on Markers of Glucose and Obesity in Postmenopausal Women: A Meta-analysis of Randomized Controlled Trials

PURPOSE

The effect of vitamin D effect on glucose markers and obesity in postmenopausal women remains controversial. The current literature contains little information on vitamin D dosage and duration for optimal efficacy in postmenopausal women. This meta-analysis was undertaken to assess the impact of vitamin D on glucose markers and obesity in postmenopausal women.

METHODS

A number of databases were used dated up to January 5, 2023, with no language restrictions (PubMed/MEDLINE, Web of Science, EMBASE, and Scopus). Treatment response from baseline was estimated from the mean within-group analysis, and SDs were used to calculate the treatment response.

FINDINGS

Nine eligible articles with 12 comparisons qualified for the final quantitative analysis. An overall decrease was noted in fasting blood glucose (weighted mean difference [WMD], -3.56 mg/dL; 95% CI, -5.49 to -1.64; P < 0.001), homeostatic model assessment for insulin resistance (WMD, -1.168 mm; 95% CI, -2.001 to -0.33; P = 0.006), insulin (WMD, -2.26 units; 95% CI, -4.35 to -0.18; P = 0.033), and glycosylated hemoglobin (WMD, -0.41%; 95% CI, -0.54 to -0.29; P < 0.001) after vitamin D administration in postmenopausal women. In subgroup analyses, a notable decrease in fasting blood glucose was detected when the intervention course was ˃6 months and dosage ≤1000 IU/d (WMD, -3.48 mg/dL). The present study showed that vitamin D was not associated with body mass index, body weight, or waist circumference in postmenopausal women.

IMPLICATIONS

Vitamin D is beneficial for glucose markers but not obesity in postmenopausal women. An individualized dosage regimen of vitamin D should be followed depending on the clinical outcome target of postmenopausal women.

Mechanisms Suggesting a Relationship between Vitamin D and Erectile Dysfunction: An Overview

Vitamin D deficiency (VDD) and erectile dysfunction (ED) heavily burden the male population. The higher prevalence of both conditions in the elderly suggests a possible relationship between the two conditions. In addition, in vitro, animal, and human studies have revealed several mechanisms that may relate VDD to ED. The main mechanism by which vitamin D might exert its action on sexual function appears to be through the regulation of endothelial function. Indeed, VDD correlates with several markers of endothelial function. The action of vitamin D on the endothelium would be exercised both indirectly through its intervention in inflammatory processes and through the production of oxygen free radicals, and directly through the regulation of vascular stiffness, the production of nitric oxide, and the regulation of vessel permeability. Furthermore, the ubiquitous distribution of the vitamin D receptor in the human body means that this hormone can also exert a beneficial effect on erectile function by interfering with those comorbidities significantly associated with ED, such as hypertension, diabetes mellitus, hypercholesterolemia, chronic kidney disease, and hypogonadism. In this review, we thoroughly and carefully presented the evidence and mechanisms that would appear to relate vitamin D levels to erectile function. Furthermore, we have summarized the meta-analytic evidence for and against this association to provide a true representation of this topic. Data published to date suggest that low levels of vitamin D could contribute to worsening erectile function through several mechanisms. Therefore, vitamin D levels should be measured in patients with ED and maintained at adequate levels by specific supplementation in case of deficiency. However, the low quality and heterogeneity of clinical trials evaluating the effects of vitamin D administration on erectile function and ED-associated comorbidities do not allow for a univocal conclusion, and indicate the need for further studies to analyze these aspects.

The effect of Spirulina supplementation on lipid profile: GRADE-assessed systematic review and dose-response meta-analysis of data from randomized controlled trials

BACKGROUND

Cardiovascular diseases (CVD) are one of the most important causes of death worldwide. Dyslipidemia is one of the main causal risk factors for CVD that can be controlled by modifying lifestyle, which entails the use of healthy diets containing functional foods. The present study was conducted to summarize the effects of Spirulina on the lipid profile in previous randomized controlled trials.

METHODS

MEDLINE, Scopus, Clarivate Analytics Web of Science, and the Cochrane Library databases were searched systematically until January 2023, for clinical interventions that investigated the effect of Spirulina supplementation on plasma lipid profile concentrations.

RESULTS

ooled results of 20 studies (with 23 arms and 1076 participants) indicated that Spirulina intervention significantly reduced LDL-C (SMD: -0.6, 95% CI: -0.9, -0.2, P˂0.05), TC (SMD: -0.6, 95% CI: -0.9, -0.2, P˂0.05) and TG (SMD: -0.6, 95% CI: -0.9, -0.2, P˂0.05) levels while HDL-C levels were significantly increased (SMD: 0.3, 95% CI: 0.0, 0.6, P˂0.05).

CONCLUSIONS

The findings of the present meta-analysis and review show the usefulness of supplementing with Spirulina in improving serum levels of TC, TG, LDL-C, and HDL-C.

Vitamin D Supplementation and Its Impact on Mortality and Cardiovascular Outcomes: Systematic Review and Meta-Analysis of 80 Randomized Clinical Trials

BACKGROUND

The impact of vitamin D supplementation on cardiovascular outcomes and mortality risk reduction remains unclear due to conflicting study findings.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), published between 1983 and 2022, that reported the effect of vitamin D supplementation in adults versus placebo or no treatment on all-cause mortality (ACM), cardiovascular mortality (CVM), non-cardiovascular mortality (non-CVM), and cardiovascular morbidities. Only studies with a follow-up period longer than one year were included. The primary outcomes were ACM and CVM. Secondary outcomes were non-CVM, myocardial infarction, stroke, heart failure, and major or extended adverse cardiovascular events. Subgroup analyses were performed according to low-, fair- and good-quality RCTs.

RESULTS

Eighty RCTs were assessed, including 82,210 participants receiving vitamin D supplementation and 80,921 receiving placebo or no treatment. The participants' mean (SD) age was 66.1 (11.2) years, and 68.6% were female. Vitamin D supplementation was associated with a lower risk of ACM (OR: 0.95 [95%CI 0.91-0.99] p = 0.013), was close to statistical significance for a lower risk of non-CVM (OR: 0.94 [95%CI 0.87-1.00] p = 0.055), and was not statistically associated with a lower risk of any cardiovascular morbi-mortality outcome. Meta-analysis of low-quality RCTs showed no association with cardiovascular or non-cardiovascular morbi-mortality outcomes.

CONCLUSIONS

The emerging results of our meta-analysis present evidence that vitamin D supplementation appears to decrease the risk of ACM (especially convincing in the fair- and good-quality RCTs), while not showing a decrease in the specific cardiovascular morbidity and mortality risk. Thus, we conclude that further research is warranted in this area, with well-planned and executed studies as the basis for more robust recommendations.

Correlation of Vitamin 25(OH)D, Liver Enzymes, Potassium, and Oxidative Stress Markers with Lipid Profile and Atheromatic Index: A Pilot Study

According to recent literature, there is a limited amount of data about the correlation of vitamin 25(OH)D, potassium (K), oxidative stress parameters, and other biomarkers with dyslipidemia, which is an established risk factor for cardiovascular diseases (CVDs). This study aims to investigate the correlation of lipid profile and atheromatic index TC/HDL with several biomarkers and oxidative stress parameters. A total of 102 volunteers, 67 with atheromatic index TC/HDL > 3.5 (Group A) and 35 with TC/HDL < 3.5 (Group B), aged from 26 to 78 years, participated in this study. Serum levels of triglycerides (TG), total cholesterol (TC), low- and high-density lipoproteins (LDL and HDL), vitamin 25(OH)D [25(OH)D], potassium (K), sodium (Na), lactose dehydrogenase (LDH), liver enzymes including serum glutamic oxaloacetic and glutamic pyruvic transaminases (SGOT and SGPT), gamma-glutamyl transferase (γ-GT), and alkaline phosphatase (ALP) were analyzed using standard photometric methods. Oxidative stress parameters such as reactive oxygen species (ROS) were detected with fluorometric methods, whereas total oxidative (TOS) and antioxidative status (TAS) were measured with spectrophotometric methods. According to the results, negative correlations of HDL (r = −0.593) and 25(OH)D (r = −0.340) and K (r = −0.220) were found, and positive expected correlations of LDL (r = 0.731), TC (r = 0.663), and TG (r = 0.584) with atheromatic index in the total studied sample were found. In conclusion, patients with a dyslipidemic profile should frequently check not only their lipid profile but also other biomarkers such as 25(OH)D, potassium, and oxidative stress markers to predict dyslipidemia and avoid subsequent disorders.

EMAS position statement: Vitamin D and menopausal health

INTRODUCTION

There is increasing evidence that vitamin D has widespread tissue effects. In addition to osteoporosis, vitamin D deficiency has been associated with cardiovascular disease, diabetes, cancer, infections and neurodegenerative disease. However, the effect of vitamin D supplementation on non-skeletal outcomes requires clarification, especially in postmenopausal women.

AIM

This position statement provides an evidence-based overview of the role of vitamin D in the health of postmenopausal women based on observational and interventional studies.

MATERIALS AND METHODS

Literature review and consensus of expert opinion.

RESULTS AND CONCLUSIONS

Vitamin D status is determined by measuring serum 25-hydroxyvitamin D levels. Concentrations <20 ng/ml (<50 nmol/l) and <10 ng/ml (<25 nmol/l) are considered to constitute vitamin D deficiency and severe deficiency, respectively. Observational data suggest an association between vitamin D deficiency and adverse health outcomes in postmenopausal women, although they cannot establish causality. The evidence from randomized controlled trials concerning vitamin D supplementation is not robust, since many studies did not consider whether people were deficient at baseline. Moreover, high heterogeneity exists in terms of the population studied, vitamin D dosage, calcium co-administration and duration of intervention. Concerning skeletal health, vitamin D deficiency is associated with low bone mass and an increased risk of fractures. Vitamin D supplementation at maintenance doses of 800-2000 IU/day (20-50 μg/day), after repletion of vitamin D status with higher weekly or daily doses, may be of benefit only when co-administered with calcium (1000-1200 mg/day), especially in the elderly populations and those with severe vitamin D deficiency. Concerning cardiovascular disease, vitamin D deficiency is associated with an increased prevalence of cardiovascular risk factors, mainly metabolic syndrome, type 2 diabetes mellitus and dyslipidemia. Vitamin D deficiency, especially its severe form, is associated with an increased risk of cardiovascular events (coronary heart disease, stroke, mortality), independently of traditional risk factors. Vitamin D supplementation may have a modestly beneficial effect on lipid profile and glucose homeostasis, especially in obese individuals or those ≥60 years old and at doses of ≥2000 IU/day (≥50 μg/day). However, it has no effect on the incidence of cardiovascular events. Concerning cancer, vitamin D deficiency is associated with increased incidence of and mortality from several types of cancer, such as colorectal, lung and breast cancer. However, the data on other types of gynecological cancer are inconsistent. Vitamin D supplementation has no effect on cancer incidence, although a modest reduction in cancer-related mortality has been observed. Concerning infections, vitamin D deficiency has been associated with acute respiratory tract infections, including coronavirus disease 2019 (COVID-19). Vitamin D supplementation may decrease the risk of acute respiratory tract infections and the severity of COVID-19 (not the risk of infection). Concerning menopausal symptomatology, vitamin D deficiency may have a negative impact on some aspects, such as sleep disturbances, depression, sexual function and joint pains. However, vitamin D supplementation has no effect on these, except for vulvovaginal atrophy, at relatively high doses, i.e., 40,000-60,000 IU/week (1000-1500 IU/week) orally or 1000 IU/day (25 μg/day) as a vaginal suppository.

Higher Dietary Vitamin D Intake Influences the Lipid Profile and hs-CRP Concentrations: Cross-Sectional Assessment Based on The National Health and Nutrition Examination Survey

Background. An unanswered question in the field of nutrition is whether there is an association between vitamin D intake and the lipid profile in adults. We conducted this cross-sectional study in order to investigate the impact of vitamin D intake on the lipid profile of adults in the context of the 2017-2018 National Health and Nutrition Examination Survey (NHANES). Methods. Serum lipids and high-sensitivity C-reactive protein (hs-CRP) concentrations and the Vitamin D intake in 2588 people aged 19 to 70 years was collected using laboratory analysis and 24-h recall, respectively. The one-way ANOVA test was used to compare quantitative variables and the chi-squared test was used to compare qualitative ones. Multivariate logistic regression for three models was performed to assess the odds ratio (OR) of high total cholesterol (TC) (>200 mg/dL), triglycerides (TG) (>150 mg/dL), low-density lipoprotein cholesterol (LDL-C) (>115 mg/dL), high-density lipoprotein cholesterol (HDL-C) (<40 mg/dL) and hs-CRP (>1 mg/l) based on the tertiles of dietary vitamin D (D2 + D3) intake. Results. After adjusting for age, sex, race, body mass index, serum 25-hydroxyvitamin D2, alcohol intake, energy intake, protein intake, carbohydrate intake, fiber intake and fat intake, individuals in the tertile with the highest versus lowest vitamin D intake (>1 mcg/day vs. <0.10 mcg/day) had lower odds of displaying elevated TC, LDL-C and hs-CRP concentrations (OR 0.57; CI: 0.37 to 0.88; P-trend: 0.045, OR 0.59; CI: 0.34 to 1.01; P-trend: 0.025 and OR 0.67; CI: 0.45 to 0.99; P-trend: 0.048, respectively). Based on the results of the logistic regression, no correlation between vitamin D intake and changes in TG or HDL-C values was noted. Conclusions. Our cross-sectional study indicates that higher dietary vitamin D (D2 + D3) intake is associated with lower TC, LDL-C and hs-CRP levels. No relationship between dietary vitamin D intake and TG or HDL-C values was detected. Further large-scale randomized trials are needed to evaluate the actual association between dietary vitamin D intake and the lipid profile.

Vitamin D, Menopausal Health and COVID-19: Critical Appraisal of Current Data

Inconsistency exists across studies conducted in postmenopausal women regarding the effect of vitamin D deficiency (VDD) and supplementation on several aspects of menopausal health, such as fractures, vasomotor symptomatology, cardiovascular disease (CVD), cancer and infections, including coronavirus disease 2019 (COVID-19). The aim of this review is to critically summarize the evidence provided by observational studies and randomized controlled trials (RCTs) of vitamin D supplementation in postmenopausal women with VDD. Observational studies have found that VDD is associated with an increased risk of falls and fractures after the menopause. VDD also has a negative effect on menopausal symptomatology. VDD, especially its severe form, is associated with an increased risk of CVD risk factors and CVD events. VDD is associated with increased risk and mortality from several cancer types and risk of infections. The evidence from RCTs regarding the effect of vitamin D supplementation on falls, fractures, menopausal symptoms, cardiovascular disease, cancer and infections is not robust. Thus, skeletal health may benefit only when vitamin D is co-administered with calcium, especially in those ≥70 years old and with severe VDD. There is no evidence of a favorable effect on menopausal symptoms or risk of CVD or cancer, except for a modest reduction in cancer-related mortality. Inconsistency still exists regarding its effect on infection risk, disease severity and mortality due to COVID-19.

Does Omega-3 Fatty Acid Supplementation Have Favorable Effects on the Lipid Profile in Postmenopausal Women? A Systematic Review and Dose-response Meta-analysis of Randomized Controlled Trials

PURPOSE

Menopause is associated with disturbances in the metabolism of lipids. Moreover, during the postmenopausal period, female subjects are more prone to develop dyslipidemia. Omega-3 fatty acids, which exert cardioprotective, anti-inflammatory, and lipid-lowering actions, are commonly recommended in postmenopausal women. However, their effect on serum lipids in this population remains unclear. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to clarify this research question.

METHODS

We systematically searched the Web of Science, Scopus, PubMed/MEDLINE, and EMBASE databases from their inception until January 3, 2022. The DerSimonian and Laird random-effects model was used to combine effect sizes.

FINDINGS

Omega-3 fatty acid supplementation resulted in a decrease in triglyceride concentrations (weighted mean difference [WMD], -17.8 mg/dL; 95% CI, -26 to -9.6; P < 0.001), particularly in the RCTs that lasted ≤16 weeks (WMD, -18.6 mg/dL), when the baseline triglyceride concentrations were ≥150 mg/dL (WMD, -22.8 mg/dL), in individuals with a body mass index ≥30 kg/m² (WMD, -19.3 mg/dL), and when the dose of omega-3 fatty acids was ≥1 g/d (WMD, -21.10 mg/dL). LDL-C (WMD, 4.1 mg/dL; 95% CI, 1.80 to 6.36; P < 0.001) and HDL-C (WMD, 2.1 mg/dL; 95% CI, 0.97 to 3.2; P < 0.001) values increased. Total cholesterol levels (WMD, -0.15 mg/dL; 95% CI, -4 to 3.74; P = 0.94) remained unchanged after administration of omega-3 fatty acids.

IMPLICATIONS

In postmenopausal women, supplementation with omega-3 fatty acids resulted in a significant reduction in triglyceride concentrations and a modest elevation in HDL-C and LDL-C levels, whereas this intervention did not affect total cholesterol values.

The Effect of Anastrozole on the Lipid Profile: Systematic Review and Meta-analysis of Randomized Controlled Trials

PURPOSE

We aimed to investigate the impact of anastrozole administration on the traditional components of the lipid profile (ie, total cholesterol [TC], LDL-C, HDL-C, and triglycerides [TGs]) by means of a systematic review and meta-analysis of randomized controlled trials.

METHODS

We searched the PubMed/Medline, Scopus, Embase, and Web of Science databases for relevant randomized controlled trials published in the English language until January 18, 2022. The weighted mean difference (WMD) and 95% CIs were calculated using a random-effects model (DerSimonian and Laird methods).

FINDINGS

Anastrozole administration significantly lowered TC concentrations when the treatment duration was ≤3 months (WMD = -2.73 mg/dL; 95% CI, -5.09 to -0.38 mg/dL; P = 0.02) and when the baseline TC concentration was ≥200 mg/dL (WMD = -3.64 mg/dL; 95% CI, -6.30 to -0.98 mg/dL; P = 0.007). HDL-C levels decreased after anastrozole administration when the treatment duration was >3 months (WMD = -1.67 mg/dL; 95% CI, -3.24 to -0.10 mg/dL; P = 0.03). Anastrozole administration had no impact on TG or LDL-C values.

IMPLICATIONS

Anastrozole administration in humans can decrease TC and HDL-C levels but has no effect on LDL-C or TG concentrations.

Shift Work and Serum Vitamin D Levels: A Systematic Review and Meta-Analysis

Vitamin D deficiency and insufficiency are highly prevalent conditions worldwide due to several factors, including poor sun exposure. Shift workers may be exposed to the risk of hypovitaminosis D due to fewer opportunities for sunlight exposure compared to day workers. A systematic review of the PubMed, SCOPUS, and EMBASE databases was conducted according to the Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) statement to investigate the effect of shift work on vitamin D levels. Mean differences (MD) and 95% confidence intervals (CI) of serum 25-OH-D levels in shift workers and non-shift workers were calculated. A total of 13 cross-sectional studies were included in the meta-analysis. We found significantly lower levels of serum 25-OH-D in shift workers compared with non-shift workers (MD: −1.85, 95% CI [−2.49 to −1.21]). Heterogeneity among included studies was high (I2 = 89%, p < 0.0001), and neither subgroup analysis nor meta-regression were able to identify specific sources of the heterogeneity that may be related to the different characteristics of shift work among studies. The monitoring of serum vitamin D levels and prompt correction of any deficiencies should be considered in shift workers. Notably, since a large part of the observations are derived from Koreans, larger epidemiological studies are needed in other populations.

Vitamin D Status, Cardiovascular Risk Profile, and miRNA-21 Levels in Hypertensive Patients: Results of the HYPODD Study

The vitamin D and microRNA (miR) systems may play a role in the pathogenesis of cardiometabolic disorders, including hypertension. The HYPODD study was a double-blind placebo-controlled trial aiming to assess the effects of cholecalciferol treatment in patients with well-controlled hypertension and hypovitaminosis D (25OHD levels < 50 nmol/L). In addition to this clinical trial, we also evaluated the effects of cholecalciferol and calcitriol treatment on miR-21 expression in vivo and in vitro, respectively. Changes in the cardiovascular risk profiles were evaluated in HYPODD patients treated with cholecalciferol (C-cohort) or with placebo (P-cohort). The miR-21circulating levels were measured in four C-cohort patients and five P-cohort patients. In vitro, the miR-21 levels were measured in HEK-293 cells treated with calcitriol or with ethanol vehicle control. Cholecalciferol treatment increased 25OHD levels and reduced parathormone, total cholesterol, and low-density lipoprotein cholesterol levels in C-cohort patients, whereas no significant changes in these parameters were observed in P-cohort patients. The miR-21 circulating levels did not change in the C- or the P-cohort patients upon treatment. Calcitriol treatment did not affect miR-21 levels in HEK-293 cells. In conclusion, hypovitaminosis D correction ameliorated the cardiovascular risk profiles in hypertensive patients treated with cholecalciferol but did not influence the miR-21 expression.

The Multiple Effects of Vitamin D against Chronic Diseases: From Reduction of Lipid Peroxidation to Updated Evidence from Clinical Studies

Background: Vitamin D exerts multiple beneficial effects in humans, including neuronal, immune, and bone homeostasis and the regulation of cardiovascular functions. Recent studies correlate vitamin D with cancer cell growth and survival, but meta-analyses on this topic are often not consistent. Methods: A systematic search of the PubMed database and the Clinical Trial Register was performed to identify all potentially relevant English-language scientific papers containing original research articles on the effects of vitamin D on human health. Results: In this review, we analyzed the antioxidant and anti-inflammatory effects of vitamin D against acute and chronic diseases, focusing particularly on cancer, immune-related diseases, cardiomyophaties (including heart failure, cardiac arrhythmias, and atherosclerosis) and infectious diseases. Conclusions: Vitamin D significantly reduces the pro-oxidant systemic and tissue biomarkers involved in the development, progression, and recurrence of chronic cardiometabolic disease and cancer. The overall picture of this review provides the basis for new randomized controlled trials of oral vitamin D supplementation in patients with cancer and infectious, neurodegenerative, and cardiovascular diseases aimed at reducing risk factors for disease recurrence and improving quality of life.