Vitamin D deficiency is associated with atherosclerosis-promoting risk factor clustering but not vascular damage in children

Association of adiposity, serum vitamin D, and dietary quality with cardiometabolic risk factors in children aged 6-12 years: findings from SEANUTS II Malaysia

Increased cardiometabolic risk among children is increasingly becoming a concern, with evidence indicating that obesity, diet, and serum 25-hydroxyvitamin D (25(OH)D) are associated with cardiometabolic risk. However, such studies among Malaysian children are scarce. Thus, this study explores the associations between adiposity, dietary quality, and 25(OH)D, with cardiometabolic risk factors among Malaysian children aged 4-12 years. Data of 479 children (mean age: 8.2 ± 2.3 years old, 52% females) from the South East Asian Nutrition Surveys (SEANUTS II) Malaysia, were included in this analysis. Adiposity (percentage of body fat) was assessed with bioelectrical impedance technique. Dietary quality was assessed using 24 h dietary recall and calculated as mean adequacy ratio. Vitamin D was assessed based on serum 25-hydroxyvitamin D (25(OH)D). Measurements of cardiometabolic risk factors included waist circumference (WC), mean arterial pressure (MAP), fasting blood glucose (FBG), high-density lipoprotein (HDL), triglyceride, and high-sensitivity C-reactive protein, and cardiometabolic risk cluster score (siMS) was calculated. Overall, higher adiposity was positively associated with all cardiometabolic risk factors (WC, ß = 0.907; 95% CI = 0.865, 0.948; MAP, ß = 0.225; 95% CI = 0.158, 0.292; HDL, ß = -0.011; 95% CI = -0.014, -0.009; Triglyceride, ß = 0.012; 95% CI = 0.009, 0.016; FBG, ß = 0.006; 95% CI = 0.002, 0.011) and siMS score (ß = 0.033; 95% CI = 0.029, 0.037). Serum 25(OH)D was inversely associated with siMS score (ß = -0.002; 95% CI = -0.004, -0.000008) and positively associated with HDL (ß = 0.002; 95% CI = 0.0001, 0.003). Our findings suggest that adiposity is a key determinant of adverse cardiometabolic risk factors in children, while serum 25(OH)D may be associated with overall cardiometabolic health. Interventions to reduce obesity are needed to mitigate the deleterious consequences of cardiometabolic dysregulation in children.

Longitudinal Associations Between Vitamin D Status and Cardiometabolic Risk Markers Among Children and Adolescents

CONTEXT

Vitamin D status has previously been associated with cardiometabolic risk markers in children and adolescents. In particular, it has been suggested that children with obesity are more prone to vitamin D deficiency and unfavorable metabolic outcomes compared with healthy-weight children.

OBJECTIVE

To conduct a longitudinal study assessing this association in children and stratify by body mass index (BMI) category.

METHODS

Children from the pan-European IDEFICS/I.Family cohort with at least one measurement of serum 25-hydroxyvitamin D [25(OH)D] at cohort entry or follow-up (n = 2171) were included in this study. Linear mixed-effect models were used to assess the association between serum 25(OH)D as an independent variable and z-scores of cardiometabolic risk markers (waist circumference, systolic [SBP] and diastolic blood pressure [DBP], high- [HDL] and low-density lipoprotein, non-HDL, triglycerides [TRG], apolipoprotein A1 [ApoA1] and ApoB, fasting glucose [FG], homeostatic model assessment for insulin resistance [HOMA-IR], and metabolic syndrome score) as dependent variables.

RESULTS

After adjustment for age, sex, study region, smoking and alcohol status, sports club membership, screen time, BMI, parental education, and month of blood collection, 25(OH)D levels were inversely associated with SBP, DBP, FG, HOMA-IR, and TRG. The HOMA-IR z-score decreased by 0.07 units per 5 ng/mL increase in 25(OH)D. The 25(OH)D level was consistently associated with HOMA-IR irrespective of sex or BMI category.

CONCLUSION

Low serum 25(OH)D concentrations are associated with unfavorable levels of cardiometabolic markers in children and adolescents. Interventions to improve vitamin D levels in children with a poor status early in life may help to reduce cardiometabolic risk.

Vitamin D Deficiency and Carotid Media-Intima Thickness in Childhood Cancer Survivors

Childhood cancer survivors (CCS) are predisposed to developing numerous late effects of anticancer treatment later in life. The existing literature suggests that vitamin D deficiency (VDD) may influence cardiovascular abnormalities and metabolic diseases. The objectives of this study were to investigate the prevalence of VDD among childhood cancer survivors and examine the association of vitamin D deficiency and carotid intima-media thickness (IMT). The study comprised 111 childhood cancer survivors (62 males, 49 females) with a median follow-up time of 6.14 years. Vitamin D status was determined by measuring serum 25(OH)D levels using the automatic immunoenzymatic method. Ultrasonography of the common carotid artery (CCA), the carotid bulb, and the proximal part of the internal carotid artery (ICA) was conducted. Vitamin D deficiency (<20 ng/mL) was detected in 69.4% of CCS. A higher parathormone level and increased BMI were observed among VDD survivors. No effects of type of diagnosis, radiotherapy or hematopoietic stem cell transplantation on vitamin D status were observed. Our findings reveal that survivors with VDD exhibited significantly greater thickness in the CCA and carotid bulb. In conclusion, the results of our study of childhood cancer survivors demonstrate that vitamin D deficiency is prevalent in up to 70% of individuals. We did not confirm the hypothesis that factors related to anticancer treatment used during childhood contributed to the higher prevalence of VDD. Additionally, we did not verify the contribution of vitamin D deficiency to the increase in IMT thickness.

Serum 25-Hydroxyvitamin D correlates with systolic blood pressure in obese male schoolchildren

INTRODUCTION

Childhood obesity is associated with an increased risk of chronic diseases. We aimed to examine the relation between serum levels of 25-hydroxyvitamin D (25[OH]D) and blood pressure in obese schoolchildren.

MATERIAL AND METHODS

Cross-sectional study in school-age children with obesity. The serum levels of 25(OH)D were measured and classified as sufficient or insufficient/deficient. Blood pressure was measured. Normal values were considered <90th percentile, elevated blood pressure ≥90th to <95th percentiles, and hypertension ≥95th percentile, according to blood pressure reference tables, specific for age, sex, and height. The Pearson correlation was performed.

RESULTS

256 obese schoolchildren (123 [48.0%] females and 133 [51.9 %] males) were evaluated. The prevalence rates of vitamin D deficiency, insufficiency, and sufficiency were 23.4%, 52.3%, and 24.2%, respectively. Normal blood pressure was observed in 101 (39.4%) children; the frequencies of elevated blood pressure and hypertension were 10.9% and 49.6%, respectively. A moderate inverse correlation of 25(OH) D levels with systolic blood pressure levels (r = -0.54, p = 0.03) was observed. When analyzed by sex, a significantly high inverse correlation between 25(OH)D levels and systolic blood pressure was observed in males (r=-0.85 and p=<0.001). No significant correlation was found in females (systolic r=-0.16 and p=0.67; diastolic r= -0.15 and p=0.812). When performing the multiple regression analysis, the 25(OH)D levels and body mass index (BMI) were the significant predictors for systolic blood pressure.

CONCLUSIONS

We identified an inverse correlation between 25[OH]D levels and systolic blood pressure in male schoolchildren with obesity.

Sex differences in the association of vitamin D and metabolic risk factors with carotid intima-media thickness in obese adolescents

BACKGROUND

It has been shown that vitamin D is associated with obesity and the development of atherosclerosis. Less is known about this association among adolescents with obesity.

OBJECTIVES

To determine the association of vitamin D level and metabolic risk factors with carotid intima-media thickness (CIMT) among obese adolescents.

METHODS

We conducted a cross-sectional study among obese children aged 15 to 17 years in Yogyakarta, Indonesia. The association of vitamin D and other metabolic risk factors (triglyceride, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), and insulin resistance using homeostasis model assessment of insulin resistance (HOMA-IR)) with CIMT was explored by multivariable linear regression models.

RESULTS

Out of 156 obese adolescents, 55.8% were boys. Compared to girls, boys had higher BMI z-score, waist circumference, and HDL-cholesterol. After adjustment for age, sex and second-hand smoke exposure, high HOMA-IR, total cholesterol, LDL-cholesterol and triglyceride levels were associated with higher odds of elevated CIMT. In analyses stratified by sex, a similar trend was observed in boys, while none of the risk factors were associated with CIMT in girls. We observed no association between vitamin D and CIMT.

CONCLUSIONS

Hyperinsulinemia, higher total cholesterol and LDL cholesterol were associated with greater odds of elevated CIMT among obese adolescent boys.

Vitamin D status and blood pressure in children and adolescents: a systematic review of observational studies

BACKGROUND

Childhood hypertension is a growing public health problem. Simultaneously, hypovitaminosis D is widespread in this population and could be associated with hypertension. This study systematically reviewed the literature on the relationship between vitamin D status and blood pressure (BP) in children and adolescents.

METHODS

Following the PRISMA guidelines, PUBMED, MEDLINE, CINAHL, EMBASE, Cochrane Library, and ClinicalTrials.gov and the gray literature without language or time restrictions were searched. We included observational studies, assessed their risk of bias, and extracted data on population characteristics, vitamin D status and BP measurements, and the association between the two variables. A narrative analysis of the studies was performed.

RESULTS

In total, 85 studies were included. Prospective cohort studies showed no association between vitamin D and BP, and generally, they were flawed. Also, the majority of non-prospective cohort studies (cross-sectional, retrospective, case-control) did not report an association between vitamin D and BP. They were mostly flawed regarding BP measurement and adjusting to potential confounders.

CONCLUSION

The results on the relationship between vitamin D status and BP in children and adolescents varied between the studies, and mainly pointed towards lack of association.

Association of circulating 25-hydroxyvitamin D and parathyroid hormone with carotid intima media thickness in children and adolescents with excess weight

Evidence on the association of vitamin D and parathyroid hormone (PTH) with cardiovascular risk factors in the young is limited. We therefore assessed the relationships of circulating vitamin D and PTH concentrations and subclinical atherosclerosis in overweight or obese children and adolescents. This was a cross-sectional study, investigated the association of 25-hydroxyvitamin D (25(OH)D), intact PTH (iPTH), and iPTH/25(OH)D ratio with carotid intima-media thickness (cIMT) in 368 Iranian children and adolescents with a body mass index (BMI) ≥1 z-score based on WHO criteria. Ultrasound measurement of cIMT was performed. Multivariable linear and logistic regressions were used to test associations between 25(OH)D, iPTH, and iPTH/25(OH)D ratio using one-ln-unit increment with cIMT. Median (25-75 interquartile range) 25(OH)D and iPTH concentrations were 11.8 (8.2-18.6) ng/ml and 38.2 (25.0-61.4) pg/ml, respectively. Among boys, each one-ln-unit increase of iPTH and iPTH/25(OH)D ratio was significantly associated with 0.194 mm and 0.147 mm increase, respectively, in cIMT, after adjustment for confounders. A similar pattern of association was observed between iPTH (β = 0.143, p = 0.037) and iPTH/25(OH)D ratio (β=0.172, p = 0.007) with cIMT among obese participants. Furthermore, among obese participants in the fully adjusted model, each one-ln-unit increase of iPTH and 25(OH)D/iPTH ratio was significantly associated with 53% and 39% increased odds of having high cIMT, respectively. Girls and those who were overweight did not show any significant association of 25(OH)D, iPTH, and iPTH/25(OH)D ratio with cIMT. High iPTH and iPTH/25(OH)D ratio were associated with increased cIMT in boys and those who are obese.

Vitamin D, Low-Grade Inflammation and Cardiovascular Risk in Young Children: A Pilot Study

Vitamin D has anti-inflammatory properties, and deficiency is prevalent in children. There is a paucity of data regarding vitamin D status and its correlation with low-grade inflammation and vasculature. We prospectively enrolled 25 children, 9-11 years old (13 male); 21 obese. Eight atherosclerosis-promoting risk factors were scored as categorical variables with the following thresholds defining abnormality: body mass index Z score ≥ 1.5; systolic blood pressure ≥ 95th percentile (for age, sex, and height); triglyceride ≥ 100 mg/dL; low-density lipoprotein cholesterol (LDL-C) ≥ 110 mg/dL; high-density lipoprotein cholesterol ≤ 45 mg/dL; hemoglobin A1C (HBA1C) ≥ 5.5; 25-hydroxyvitamin D [25(OH) D] ≤ 30 ng/mL, and tobacco smoke exposure. High-sensitivity C-reactive protein (hsCRP) was measured to assess low-grade inflammation and classified as low- (<1 mg/L), average- (1-3 mg/L), and high-risk (>3 to <10 mg/L) groups. The proportion of children within each hsCRP group who had above threshold risk factors was calculated. Carotid artery ultrasound was performed to measure carotid artery intima-media thickness (CIMT). Median (range) for 25(OH) D was 24 (17-45) ng/mL. Eighteen were either 25 (OH) D deficient (<20 ng/mL) or insufficient (20-30 ng/mL), and seven were sufficient (>30 ng/mL). hsCRP was 1.7 (0.2-9.1) mg/L, with 11 being <1.0 mg/L, 8 between 1.0-3.0 and 6 > 3.0 to < 10.0 mg/L. Risk factor score was 3.9 ± 1.7 out of eight. 25(OH) D levels did not correlate with hsCRP or CIMT. While vitamin D deficiency, inflammation, and risk factors coexist at a very young age, causative mechanisms remain unclear.

Adiponectin abates atherosclerosis by reducing oxidative stress

Background

We investigated whether the anti-atherosclerosis of adiponectin (APN) relates to the reduction of oxidative stress. We observed the overexpression of adiponectin gene with different titers on atherosclerosis (AS) models of high-fat apolipoprotein E-deficient (ApoE^−/−) mice.

Material/Methods

We divided 48 male ApoE^−/− mice into 4 groups: control group, high-fat diet group, low adiponectin group, and high adiponectin group. The low and high adiponectin group mice were treated with recombinant adenovirus expressing mice adiponectin (Ad-APN) with low-dose adiponectin 1.0×10⁸ p.f.u. and high-dose adiponectin 5.0×10⁸ p.f.u. via the tail every 2 weeks and given a high-fat diet for the last 8 weeks. On the 14^th day after injection, blood samples were obtained from the vena cava.

Results

Along with increased serum adiponectin, serum superoxide dismutase (SOD) activity increased (P<0.05) and concentration of malondialdehyde (MDA) was decreased (P<0.05). Levels of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were decreased, especially TC and LDL-C (P<0.05). A real-time fluorescent quantitative polymerase chain reaction test was used to analyze levels of mRNA expression for endothelial nitric oxide synthase (eNOS) and adiponectin in the aorta. Along with increased adiponectin, the mRNA expression of eNOS in the aorta was increased significantly (P<0.05). The lesion formation in the aortic sinus was inhibited by 25% and 31% in the low-APN group and high-APN group, respectively (P<0.05). Along with the increase of adiponectin doses, the damage of atherosclerosis gradually eased. However, the differences between the low-APN group and high-APN group had no statistical significance.

Conclusions

Adiponectin may protect the aorta from atherosclerosis injury by reducing oxidative stress, reducing lesion formation size in the aortic root and reducing TC, TG, and LDL-C in serum. The molecular mechanism may involve preservation of SOD, reducing MDA in serum, and increasing eNOS and adiponectin mRNA expression in the aorta.

Correlations between serum levels of 25-hydroxyvitamin D and carotid atherosclerosis in patients with type 2 diabetes in Shanghai

OBJECTIVE

To explore the potential association between the serum levels of 25-hydroxyvitamin D [25(OH)D] and carotid atherosclerosis in patients with type 2 diabetes.

MATERIAL AND METHODS

Three hundred and fifty patients with type 2 diabetes were enrolled in this study in Shanghai, China. B-mode ultrasound was used to detect carotid plaques as indicators of atherosclerosis and measure carotid artery intima-media wall thickness (C-IMT) at two sites of carotid artery. Subjects were divided into group A (patients with carotid plaques) and group B (patients without carotid plaques) and be assessed clinically. Serum levels of 25(OH)D and other clinical parameters were measured. Multivariate logistic regression was performed to find predictors of carotid atherosclerosis in the entire group.

RESULTS

The levels of serum 25(OH)D were lower in group A than in group B[19.60 (13.30-25.73) vs 23.19 (18.10-30.06)ng/ml, P<0.001]. The C-IMT levels [(1.00±0.17 vs 0.88±0.20)mm, Ptrend<0.001] and proportion of people with carotid plaques(44/88 vs 20/87, Ptrend<0.001) in the lowest quartile of 25(OH)D were higher than in the highest quartile. Vitamin D concentrations were inversely associated with HbA1c in women(r=-0.194, P=0.006), and C-IMT in men(r=-0.409, P<0.001). Logistic regression analysis showed age, male sex, current smoke, history of hypertension, SBP, LDL-C and lg[25(OH)D] (OR: 0.924, 95%CI: 0.893-0.955, P<0.001) were independently associated with the presence of carotid plaques in T2DM.

CONCLUSIONS

Serum vitamin D level is significantly and independently associated with carotid atherosclerosis in patients with T2DM in Shanghai, China.

Vitamin D in inflammatory diseases

Changes in vitamin D serum levels have been associated with inflammatory diseases, such as inflammatory bowel disease (IBD), rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis (MS), atherosclerosis, or asthma. Genome- and transcriptome-wide studies indicate that vitamin D signaling modulates many inflammatory responses on several levels. This includes (i) the regulation of the expression of genes which generate pro-inflammatory mediators, such as cyclooxygenases or 5-lipoxygenase, (ii) the interference with transcription factors, such as NF-κB, which regulate the expression of inflammatory genes and (iii) the activation of signaling cascades, such as MAP kinases which mediate inflammatory responses. Vitamin D targets various tissues and cell types, a number of which belong to the immune system, such as monocytes/macrophages, dendritic cells (DCs) as well as B- and T cells, leading to individual responses of each cell type. One hallmark of these specific vitamin D effects is the cell-type specific regulation of genes involved in the regulation of inflammatory processes and the interplay between vitamin D signaling and other signaling cascades involved in inflammation. An important task in the near future will be the elucidation of the regulatory mechanisms that are involved in the regulation of inflammatory responses by vitamin D on the molecular level by the use of techniques such as chromatin immunoprecipitation (ChIP), ChIP-seq, and FAIRE-seq.

Cholesterol ester transfer protein (CETP) gene polymorphism and selected parameters of lipid metabolism in children from families with history of cardiovascular system diseases

BACKGROUND

Children from families with a history of cardiovascular system diseases are especially predisposed to early development of atherosclerosis. Therefore, the aim of this study was to examine the selected lipid parameters and polymorphisms of G279A located in the cholesterol ester transfer protein (CETP) gene.

MATERIAL/METHODS

This longitudinal study was performed in 3 stages. During stage I the tests were carried out on 137 newborns after birth. Of these, we selected 30 children with a family history of cardiovascular system diseases. During stage II of the study the same children were evaluated at the age of 18-30 months, and during stage III at the age 5-6 years. Gestational age and the birth weight were evaluated in newborns. The older children were examined physically, and nutritional status was assessed. In all of the children examined, we determined the blood concentrations of triglycerides, total cholesterol, high-density lipoprotein (HDL) cholesterol, apolipoproteins (AI and B), lipoprotein(a) and polymorphisms, and the G279A locus of the CETP gene.

RESULTS

In children with genotype B1B1 (after birth and aged 5-6 years), a significantly lower cholesterol concentration in the HDL fraction was found compared to those with genotype B1B2 and B2B2. Other biochemical parameters of lipid metabolism were not significantly different between these genetic polymorphisms.

CONCLUSIONS

A lower cholesterol concentration in the HDL fraction in children with a family history of cardiovascular system diseases was determined by polymorphism of the CETP gene. Homozygotes (genotype B1B1) show a tendency towards the phenotype favoring the development of atherosclerosis.