Associations of vitamin D intake with 25-hydroxyvitamin D in overweight and racially/ethnically diverse US children

Understanding the Role of Vitamin D in Heart Failure

Vitamin D is now believed to have a significant role in cardiac signal transduction and regulation of gene expression, and thus influences normal cardiomyocyte function. It has been reported to provide cardioprotection through its anti-inflammatory, anti-apoptotic and anti-fibrotic actions; and to prevent cardiac remodeling, Ca 2 + -handling defects, and abnormal electrophysiological patterns. A vitamin D deficient state has been associated in the pathogenesis of heart failure; however, while many clinical studies report a benefit of vitamin D to heart function, other clinical studies are inconsistent with these findings. These uncertainties have led to a discord in the recommendation of vitamin D supplementation for the treatment of heart failure or as a preventive agent in patients deemed to be at risk for cardiac dysfunction. Accordingly, this article is intended to describe some of the mechanisms/sites of action of vitamin D in different animal models of heart failure, as well as to review the clinical observations and challenges in the interpretation and understanding of the clinical relevance of vitamin D in relation to heart function.

The Effect of Vitamin D Deficiency with Stunting and Overweight: A Meta-analysis Study

Background: Childhood malnutrition such as stunting and obesity is an international public health problem leading to an increased risk of mortality and morbidity. Vitamin D deficiency has also been identified as a worldwide public health issue that is associated with an increase in the prevalence of related-chronic diseases. Aim: The purpose of this study was to investigating the relation between vitamin D deficiency with stunting and  overweight  among children. Methods: This was a systematic review and meta analysis study used articles from online database of PubMed, which published in 2011 to 2021. The dependent variables was stunting and overweight. The independent variable was vitamin D deficiency. The data was analyzed by RevMan. Results: Subjects with below-standard vitamin D levels in the body had 1.86 higher risk of experiencing stunting (OR = 1.86; 95% CI 0.90-3.84; p = 0.09) and 2.76 higher being overweight (OR = 2.76; 95% CI 0.96-7.99 ; p = 0.09) compared with those with normal vitamin D levels, this result was not statistically significant. Conclusion: There is a relation between vitamin D deficiency with stunting and overweight among children under 18 years

Retrospective study of patterns of vitamin D testing and status at a single institution paediatric orthopaedics and sports clinics

OBJECTIVES

There has been a recent increase in awareness of the importance of bone health in children treated by paediatric orthopaedic and sports medicine providers. The purpose of this study was to assess our utilisation of 25 hydroxy vitamin D (25(OH)Vit D) testing in the past 10 years, and to evaluate the level of 25(OH)Vit D sufficiency in various populations of patients seen.

DESIGN

This is a single site, retrospective medical record review study.

SETTING

The study took place at a single large, private, paediatric level 1 trauma teaching hospital in the Northeast USA.

PARTICIPANTS

Our internal medical records query system identified all patients who have had 25(OH)Vit D testing in the past 10 years, from 1 January 2009 to 31 December 2018. All patients included were seen on an outpatient basis at our Orthopaedic clinics.

INTERVENTIONS

No interventions for strict research, however, eligible patients have had 25(OH)Vit D testing during their standard of care treatment.

MAIN OUTCOME MEASURES

The varying number of 25(OH)Vit D testing that occurred over the study time period within Orthopaedic groups, and by Vit D levels as sufficient, insufficient and deficient. 25(OH)Vit D sufficiency was ≥30 ng/mL, insufficiency <30 ng/mL and deficiency were <20 ng/mL. Patients were stratified and analysed.

RESULTS

Between 2009 and 2018, there were 4426 patients who had 25(OH)Vit D testing. Vitamin D testing increased significantly (p<0.001) in the past 10 years. 43% of patients had sufficient 25(OH)Vit D levels, 41% had insufficient levels and 15% had deficient levels.

CONCLUSION

More frequent testing has led to an increased identification of patients with insufficient and deficient 25(OH)Vit D levels. We found over 50% of patients tested were found to have 25(OH)Vit D levels under 30 ng/mL. There should be an increased awareness of patients with orthopaedic problems who may present with 25(OH) insufficiency.

Vitamin D status and healthy Egyptian adolescents: Where do we stand?

Vitamin D deficiency is a worldwide public health problem. Low vitamin D and its consequences among children and adolescents could be considered as one of the most important health-related problems. This study aimed to estimate the prevalence of vitamin D deficiency in healthy Egyptian adolescents and investigate factors associated with vitamin D status.A cross-sectional study was conducted on 572 school children (270 males and 302 females) aged 14 to 18 years, who were randomly selected from high schools in one governorate in Egypt. Data were collected through a self-administered questionnaire. Vitamin D level, serum calcium, phosphorus, alkaline phosphates were measured.Vitamin D deficiency was almost present in all the studied Egyptian healthy adolescents (99%), 94.8% had vitamin D deficiency and 4.2% had vitamin D insufficiency. Girls had a higher prevalence of vitamin D deficiency than boys. There was a significant association between lack of physical activity, sun exposure, and vitamin D deficiency.Vitamin D deficiency and insufficiency are highly prevalent. In sunny countries, the special pattern of conservative clothing and the lack of outdoor physical activity might be the underlying factors for the high prevalence in females. Vitamin D supplementation seems to be mandatory to halt the problem.

Intake and contribution of food groups to vitamin D intake in a representative sample of adult Greek population

OBJECTIVES

Globally, vitamin D intake from food and supplements is low, consistent with the high prevalence of low serum 25-hydroxyvitamin D concentration. The aims of this study were to assess vitamin D intake and major relevant food contributors among Greek adults and to propose subsequent policies for intervention.

METHODS

Vitamin D from diet and supplements was estimated in adults (≥19 y of age) from two 24-h recalls using the Automated Multiple-Pass Method (vitamin D from food intake) and a drug and supplement questionnaire (vitamin D supplements). Over- and underreporters were identified using the Goldberg cutoff. The final analysis included 2218 individuals. The National Research Council method was used to account for within- and between-person variation. Vitamin D food intake adequacy was estimated based on the estimated average requirement (EAR) of 10 mcg/d, set by the Institute of Medicine. Major foods contributing to intake were identified and the effect on meeting EAR, of a potential food fortification example was examined.

RESULTS

Median vitamin D intake from food ranged from 1.16 to 1.72 and 1.01 to 1.26mcg/d in different age groups in men and women, respectively. Major food sources of vitamin D were fish (46%), meat (15%), and cereals (12%); however, >90% of the population in all age groups failed to meet the EAR, even when supplemental use was accounted for (~5% of the population consumed supplements).

CONCLUSION

Overall vitamin D intake is below the average requirements. Public health policies to increase the consumption of foods high in vitamin D or food fortification may significantly reduce the percentage of individuals who do not meet the recommendations.

Pitfalls with Vitamin D Research in Musculoskeletal Disorders and Recommendations on How to Avoid Them

Reports suggesting that vitamin D may have extraskeletal roles have renewed interest in vitamin D research and stimulated publication of an increasing number of new studies each year. These studies typically assess vitamin D status by measuring the blood concentration of 25-hydroxyvitamin D [25(OH)D], the principal circulating metabolite of vitamin D. Unfortunately, variations in assay format, inconsistency in interpreting 25(OH)D concentrations, cohort bias (age, body mass index, race, season of measurements etc.) and failure to measure critical variables needed to interpret study results, makes interpreting results and comparing studies difficult. Further, variation in reporting results (reporting mean values vs. percent of the cohort that is deficient, no clear statement as to clinical relevance of effect size, etc.) further limits interstudy analyses. In this paper, we discuss many common pitfalls in vitamin D research. We also provide recommendations on avoiding these pitfalls and suggest guidelines to enhance consistency in reporting results.

Impact of Race Subgroups on the Assessment of Vitamin D Status in Adolescent Idiopathic Scoliosis

The authors' main objective was to demonstrate the confounding effect of combining subgroup data, specifically race, on the prevalence of vitamin D deficiency in adolescent idiopathic scoliosis (AIS). This was a retrospective chart review. Vitamin D deficiency was defined as 25-hydroxyvitamin D (25[OH]D) less than 20 ng/mL. Data were compared between white patients and black and Hispanic patients. Vitamin D status in girls with AIS was also compared with that in girls without AIS who had a history of fracture and with the medical literature to determine if deficiency in AIS was equal to or greater than other cohorts. Mean age was 13.9±2.3 years for the white girls with AIS (n=221) and 13.6±2.2 years for pooled non-whites (n=134). Significant racial differences were found that biased interpretation of the total pooled cohort. Mean 25(OH)D was 27.9±8.5 ng/mL for white girls with AIS vs 21.9±10.3 ng/mL for non-whites (P<.0001). Deficiency was present in 13.1% of white girls vs 47.8% of non-white girls (P<.0001). Compared with girls with fractures and with the published literature, the race-matched deficiency rates were not abnormally high in girls with AIS. Prevalence of deficiency was greater in non-whites with AIS than in whites. However, percent deficiency was not greater in girls with AIS than in race-matched cohorts without AIS. Without separating data by race, interpretation of vitamin D status can be confounded. [Orthopedics. 2019; 42(3):158-162.].

Increased Rates of Vitamin D Insufficiency in Boys With Duchenne Muscular Dystrophy Despite Higher Vitamin D3 Supplementation

Vitamin D supplementation is important for many chronic pediatric conditions to help maintain bone health; however, there is little evidence about how disease-related factors affect vitamin D status. The objective was to compare 25-hydroxyvitamin D (25(OH)D) concentrations in 3 pediatric cohorts (Duchenne muscular dystrophy [DMD], systemic lupus erythematosus [SLE], and osteogenesis imperfecta [OI]). In a retrospective study of 367 subjects, children with DMD had increased prevalence of vitamin D insufficiency (25% vs 14% [SLE] and 10% [OI], P = .002), despite higher vitamin D₃ supplementation doses. Boys with DMD also had higher weight, fat mass, and lower lean mass percentage Z scores. DMD was associated with having higher rates of vitamin D insufficiency than other comparable pediatric chronic disease cohorts, the effect of which may be modulated by clinical factors such as increased adiposity. While corroboration of these results is needed given baseline differences between the patient groups, greater vitamin D supplementation doses may be required to achieve optimal serum 25(OH)D concentrations in boys with DMD.

High Prevalence of Insufficient Vitamin D Intake and Serum 25-Hydroxyvitamin D in Chinese School-Age Children: A Cross-Sectional Study

Despite the importance of vitamin D in early stages of life, data are lacking on the levels of vitamin D intake and serum 25-hydroxyvitamin D (25-(OH)D) among Chinese school-age children. The aims of this study were to investigate the vitamin D intake and serum 25-(OH)D concentration of children aged 7 to 12 years in China, and to measure the associations between vitamin D status and children's growth and development parameters. We obtained data on vitamin D intake, serum 25-(OH)D concentration, and anthropometric measurements from a cross-sectional study on school-aged children in China. Multiple linear regression and multivariable logistic regression analyses assessed the associations mentioned above. A total of 563 children (9.5 ± 1.6 years) from six areas of China were included. Among them, 86.1% had a vitamin D intake below the recommended nutrient intake (10 μg/day), and 54.7% had vitamin D deficiency (serum 25-(OH)D <15 ng/mL). We also found that high vitamin D intake was inversely associated with the risk of vitamin D deficiency (OR = 0.836, 95% confidence interval: 0.713, 0.980), and serum 25-(OH)D concentration was positively associated with the intelligence score and body mass index-for-age Z-score (BAZ) (p < 0.05). Insufficient vitamin D intake and serum 25-(OH)D are prevalent among Chinese school-aged children. A negative association was observed between vitamin D intake and the risk of vitamin D deficiency. Moreover, vitamin D status was positively associated with intelligence and BAZ, which await confirmation in future studies.

Vitamin D3 supplementation in obese, African-American, vitamin D deficient adolescents

Objectives

Obese, African-American (AA) adolescents are at increased risk for vitamin D deficiency. The primary objective of this pilot study was to examine the effect of vitamin D supplementation upon 25-hydroxy vitamin D (25OHD) levels in obese, AA adolescents.

Methods

A randomized, double-blinded, controlled pilot study included 26 obese (BMI ≥ 95%ile), vitamin D deficient (25OHD < 20 ng/mL), pubertal AA adolescents (ages 12-17). Subjects received cholecalciferol 1000 IU or 5000 IU daily for 3 months. Serum 25OHD, vitamin D binding protein, parathyroid hormone, and cardiometabolic risk markers were obtained at baseline and post-treatment.

Results

Of 39 subjects enrolled, 26 (67%) were vitamin D deficient (mean 25OHD 12.0 ± 3.8 ng/mL) at baseline and were randomized, with 22 completing the study. Sex, age, season, pubertal stage, BMI, insulin resistance (HOMA-IR) and 25OHD were similar at baseline between the 1000 IU and 5000 IU groups. Post-treatment, 25OHD increased less in the 1000 IU group (5.6 ng/mL, p = 0.03) vs. the 5000 IU group (15.6 ng/mL, p = 0.002). 83% of the 5000 IU group and 30% of the 1000 IU group reached post-treatment 25OHD ≥ 20 ng/mL (p = 0.01); 50% of the 5000 IU group, but no subject from the 1000 IU group, achieved 25OHD ≥ 30 ng/mL (p = 0.009). We detected no group differences in mineral metabolites or cardiometabolic risk markers following supplementation.

Conclusions

Cholecalciferol dosing in excess of the current Institute of Medicine dietary reference intakes was required to achieve 25OHD levels ≥20 ng/mL in obese, AA adolescents. Supplementation of 5000 IU may be required to achieve the desired goal.

Current Evidence on Vitamin D Deficiency and Metabolic Syndrome in Obese Children: What Does the Evidence from Saudi Arabia Tell Us?

Obesity and vitamin D deficiency represent major health problems among Saudi children, and have been linked to chronic diseases. Obese children are at risk of developing vitamin D deficiency, which appears to have negative influences on energy homeostasis, impeded bone mineralisation, insulin resistance and inflammation. Evidence supporting the association between vitamin D deficiency of obese children and metabolic syndrome has not specifically been studied in early childhood. The mechanisms through which vitamin D deficiency is associated with metabolic syndrome in obese children needs further elucidation. This commentary aims to (i) summarise current knowledge of the association between vitamin D deficiency and metabolic syndrome in obese children; and (ii) discuss current evidence for the association among Saudi Arabian children.

Impact of Three Doses of Vitamin D3 on Serum 25(OH)D Deficiency and Insufficiency in At-Risk Schoolchildren

OBJECTIVE

We investigated the daily dose of vitamin D needed to achieve serum 25-hydroxyvitamin D [25(OH)D] sufficiency among schoolchildren at risk for deficiency.

STUDY DESIGN

The Daily D Health Study was a randomized double-blind vitamin D supplementation trial among racially/ethnically diverse schoolchildren (n = 685) in the northeastern United States. Children were supplemented with vitamin D3 at 600, 1000, or 2000 IU/d for 6 months. Measurements included serum 25(OH)D at baseline (October to December), 3 months (January to March), 6 months (April to June), and 12 months (6 months after supplementation).

RESULTS

At baseline, mean ± standard deviation serum 25(OH)D level was 22.0 ± 6.8 ng/mL, with 5.5% severely vitamin D deficient (<12 ng/mL), 34.1% deficient (12 to 19 ng/mL), 49.0% insufficient (20 to 29 ng/mL), and 11.4% sufficient (≥30 ng/mL). The lowest levels of serum 25(OH)D were found among black (17.9 ± 6.7 ng/mL) and Asian children (18.9 ± 4.8 ng/mL), with no baseline differences by weight status. Serum 25(OH)D increased over 6 months in all three dose groups. The 2000 IU/d group achieved a higher mean serum 25(OH)D level than the other two dose groups (33.1 vs 26.3 and 27.5 ng/mL; P < 0.001), with 59.9% of this group attaining sufficiency at 3 months and only 5.3% remaining severely deficient/deficient at 6 months. All dose groups demonstrated a fall in 25(OH)D at 12 months.

CONCLUSIONS

Children at risk for vitamin D deficiency benefited from daily sustained supplementation of 2000 IU/d compared with lower doses closer to the current recommended daily allowance for vitamin D intake. This benefit occurred over the winter months, when serum 25(OH)D level tend to fall.

Overweight and obesity are associated with lower vitamin D status in Canadian children and adolescents

INTRODUCTION

There is evidence that 25-hydroxyvitamin D levels are lower in overweight and obese youth. This study examined the relationship between weight status and 25-hydroxyvitamin D, while controlling for confounders, in Canadian youth.

METHODS

Plasma 25-hydroxyvitamin D from subjects aged 6 to 17 years from the Canadian Health Measures Survey cycles 1 (2007 to 2009) and 2 (2009 to 2011) was used. Sex-specific multiple linear regression and logistic regressions examined the relationship of overweight and obesity (body mass index ≥ 85th percentile) with 25-hydroxyvitamin D levels and the odds of 25-hydroxyvitamin D <40 nmol/L and <50 nmol/L.

RESULTS

The prevalence of risk of vitamin D deficiency (25-hydroxyvitamin D < 30 nmol/L) was 6% (95% confidence interval [CI] 3.26% to 10.12%). Vitamin D inadequacy, estimated by levels <40 nmol/L, was 15% (95% CI 10.34% to 20.39%; 19% [95% CI 13.1 to 25.6] for teenagers). Seventy per cent (95% CI 63.59 to 75.17) had levels >50 nmol/L, consistent with achieving the Recommended Dietary Allowance. In adjusted analyses, overweight/obesity (1/3 of subjects) was independently associated with lower 25-hydroxyvitamin D for both sexes after adjustment for age, race, income, season, vitamin D supplementation and daily milk consumption. For 25-hydroxyvitamin D <40 nmol/L, the overweight/obese odds ratio for males was 2.63 (95% CI 1.34 to 5.18). For 25-hydroxyvitamin D <50 nmol/L, overweight/obese odds ratios were 2.19 (95% CI 1.46 to 3.28) for males and 1.39 (95% CI 1.05 to 1.84) for females.

CONCLUSIONS

This study confirms the inverse association between adiposity and serum concentrations of 25-hydroxyvitamin D in Canadian youth and the independent association of overweight/obesity to 25-hydroxyvitamin D level and vitamin D status after adjustment for other factors.

Vitamin D deficiency is common and is associated with overweight in Mexican children aged 1-11 years

OBJECTIVE

To assess vitamin D dietary sources, intake and 25-hydroxyvitamin D status and their association with individual and sociodemographic characteristics in Mexican children.

DESIGN

Data obtained from 2695 children aged 1-11 years from the Mexican National Health and Nutrition Survey (2012) were analysed. Diet was assessed by a 141-item FFQ. 25-Hydroxyvitamin D was measured by a chemiluminescent assay.

RESULTS

Mean vitamin D intake was 3·38 (se 0·09) µg/d (135·2 (se 3·6) IU/d) among pre-school children and 2·85 (se 0·06) µg/d (114·0 (se 2·4) IU/d) in school-age children. Milk accounted for 64·4 % of vitamin D intake in pre-school children and 54·7 % in school-age children. Vitamin D deficiency (serum 25-hydroxyvitamin D<50 nmol/l) was 25·9 % in pre-schoolers and 36·6 % in school-age children. Overweight/obese school-age children had a higher risk of vitamin D deficiency compared with normal-weight children (OR=2·23; 95 % CI 1·36, 3·66; P<0·05).

CONCLUSIONS

Vitamin D intakes are low in Mexican children, and milk is the main source of the vitamin. Vitamin D deficiency is common and associated with overweight in school-age children.

Optimization of Vitamin D Status After Roux-en-Y Gastric Bypass Surgery in Obese Patients Living in Northern Climate

BACKGROUND

Patients who undergo bariatric surgery are at risk for micronutrient deficiencies. The aims of this study were to determine the prevalence and predictors of vitamin D deficiency in obese patients residing in the northern climate, and to evaluate the effectiveness of a daily maintenance dose of vitamin D 2000 IU in preventing hypovitaminosis D within 1 year after bariatric surgery.

METHODS

A cohort study involving adult patients undergoing RYGB was conducted. Longitudinal changes in serum vitamin D concentrations and clinical parameters were measured and collected.

RESULTS

Data from 134 recipients of RYGB were analyzed. Hypovitaminosis D was identified in 86 patients (64 %), and was significantly affected by seasonal change and the number of comorbidities. Follow-up data were available in 60 patients. Vitamin D sufficiency was achieved in 62.5 % of those patients with baseline vitamin D insufficiency. A dose-response relationship of vitamin D intake was observed, with the most significant increase in 25(OH)D associated with daily vitamin D intakes ≥ 2000 IU.

CONCLUSIONS

The prevalence of hypovitaminosis D before RYGB was comparable to patients living in the non-northern climate. Daily vitamin D intake meeting at least 2000 IU is associated with greater improvement in serum vitamin D concentration.

25-Hydroxyvitamin D and glycemic control: A cross-sectional study of children and adolescents with type 1 diabetes

AIM

The objective of this study was to describe the vitamin D status of children and adolescents with type 1 diabetes and to evaluate whether levels of 25-hydroxyvitamin D are significantly associated with HbA1c in this population.

METHODS

197 children and adolescents from a diabetes center in a children's hospital were recruited during regular follow up visit. Non-fasting blood samples were collected to measure 25-hydroxyvitamin D and blood glucose levels. HbA1c and other key variables were abstracted from patients' medical records.

RESULTS

Of the 197 children and adolescents, more than half were adolescents, males, and Caucasian. 23% were overweight, while 13% were obese. Mean HbA1c was 8.6±1.4% (70±15.3mmol/mol). 40.6% of patients had 25-hydroxyvitamin D levels ≤50nmol/L; 49.2% had 25-hydroxyvitamin D levels between 51 and 75nmol/L and 10.2% had 25-hydroxyvitamin D levels >75nmol/L. The bivariate relationship between 25-hydroxyvitamin D and HbA1c almost reached statistical significance (P=0.057), while no significance was established in the multivariate model.

CONCLUSIONS

To the best of our knowledge this is the first study that has been adequately-powered to examine the association between 25-hydroxyvitamin D and HbA1c in children and adolescents with T1DM. This study demonstrated the high prevalence of patients with low levels of 25-hydroxyvitamin D specifically in healthy weight and Caucasian children and adolescents with T1DM. These data suggest the need for monitoring of 25-hydroxyvitamin D in all youth with T1DM.

Interlaboratory Trial for Measurement of Vitamin D and 25-Hydroxyvitamin D [25(OH)D] in Foods and a Dietary Supplement Using Liquid Chromatography-Mass Spectrometry

Assessment of total vitamin D intake from foods and dietary supplements (DSs) may be incomplete if 25-hydroxyvitamin D [25(OH)D] intake is not included. However, 25(OH)D data for such intake assessments are lacking, no food or DS reference materials (RMs) are available, and comparison of laboratory performance has been needed. The primary goal of this study was to evaluate whether vitamin D3 and 25(OH)D3 concentrations in food and DS materials could be measured with acceptable reproducibility. Five experienced laboratories from the United States and other countries participated, all using liquid chromatography tandem-mass spectrometry but no common analytical protocol; however, various methods were used for determining vitamin D3 in the DS. Five animal-based materials (including three commercially available RMs) and one DS were analyzed. Reproducibility results for the materials were acceptable. Thus, it is possible to obtain consistent results among experienced laboratories for vitamin D3 and 25(OH)D3 in foods and a DS.

Vitamin D deficiency in school-age children is associated with sociodemographic and lifestyle factors

BACKGROUND

There is concern about a reemergence of vitamin D deficiency in children in developed countries.

OBJECTIVES

The aims of this study were to describe vitamin D status in the Generation R study, a large multiethnic cohort of 6-y-old children in The Netherlands, and to examine sociodemographic, lifestyle, and dietary determinants of vitamin D deficiency.

METHODS

We measured serum 25-hydroxyvitamin D [25(OH)D] concentrations in 4167 children aged 6 y and defined deficiency following recommended cutoffs. We examined the associations between subject characteristics and vitamin D deficiency with the use of multivariable logistic regression analyses.

RESULTS

Serum 25(OH)D concentrations ranged from 4 to 211 nmol/L (median: 64 nmol/L), with 6.2% of the children having severely deficient (<25 nmol/L), 23.6% deficient (25 to <50 nmol/L), 36.5% sufficient (50 to <75 nmol/L), and 33.7% optimal (≥75 nmol/L) 25(OH)D concentrations. The prevalence of vitamin D deficiency [25(OH)D <50 nmol/L] was higher in winter (51.3%) than in summer (10.3%); and higher in African, Asian, Turkish, and Moroccan children (54.5%) than in those with a Dutch or other Western ethnic background (17.6%). In multivariable models, several factors were associated with vitamin D deficiency, including household income (OR: 1.74; 95% CI: 1.34, 2.27 for low vs. high income), child age (OR: 1.39; 95% CI: 1.20, 1.62 per year), child television watching (OR: 1.32; 95% CI: 1.06, 1.64 for ≥2 vs. <2 h/d), and playing outside (OR: 0.71; 95% CI: 0.57, 0.89 for ≥1 vs. <1 h/d). In a subgroup with dietary data (n = 1915), vitamin D deficiency was associated with a lower diet quality, but not with vitamin D intake or supplement use in early childhood.

CONCLUSIONS

Suboptimal vitamin D status is common among 6-y-old children in The Netherlands, especially among non-Western children and in winter and spring. Important modifiable factors associated with vitamin D deficiency were overall diet quality, sedentary behavior, and playing outside.

Factors associated with 25-hydroxyvitamin D levels in patients with liver cirrhosis

INTRODUCTION

Lower 25-hydroxyvitamin D [25(OH)D] levels have been observed in cirrhotic patients and have been related to disease severity. However, most previous studies included patients with very advanced disease, lacking an adequate control for other variables that could interfere with vitamin D levels. We sought to investigate the prevalence of hypovitaminosis D and the factors related to its occurrence.

MATERIAL AND METHODS

This cross-sectional study included 133 cirrhotic patients and 30 healthy controls. Bivariate and multivariate analyses were performed to determine factors associated with 25(OH)D levels below the lower tertile. Thirty patients who had been recently hospitalized were compared in two time points.

RESULTS

Mean 25(OH)D levels were 32.34 ± 11.38 in controls and 27.03 ± 6.22 ng/mL in patients (P = 0.018). 25(OH)D levels were < 30 ng/mL in 69.9% and < 20 ng/mL in 14.3% of the sample. Levels of 25(OH)D below the lower tertile (< 24 ng/mL) were independently associated with higher triceps skinfold and non-Caucasian race. Parathyroid hormone above the reference value (65 pg/mL) was found in 24.6% of patients without association with 25(OH)D or severity of liver disease. Significantly lower levels of 25(OH)D were found at the time of acute decompensation of cirrhosis.

CONCLUSIONS

In conclusion, hypovitaminosis D was prevalent in cirrhotics and it was associated with adiposity and non-Caucasian race in stable patients with relatively well preserved liver function. However, significantly lower levels were observed during admission for acute decompensation suggesting an impact of systemic inflammation or liver dysfunction on 25(OH)D levels.

Obesity, lifestyle and socio-economic determinants of vitamin D intake: a population-based study of Canadian children

OBJECTIVE

Vitamin D intake in childhood is primarily for the prevention of rickets. Inconsistent evidence has associated adequate blood concentrations with a decreased risk of certain health conditions. Further, obese individuals may have lower vitamin D status. The estimated average requirement (EAR) for children recently doubled to 400 IU/day. Our aim was to examine dietary intake of vitamin D in different body mass index (BMI) categories, in addition to assessing determinants.

METHODS

Data from two provincial surveys of grade 5 children, including a food frequency questionnaire and measured BMI, were used. Rao-Scott chi-square statistic tested the bivariate association between provinces and adequate dietary vitamin D intake. Key correlates were examined using multi-level logistic regression.

RESULTS

Those below the EAR differed between Alberta (78%) and Nova Scotia (81%). Those drinking &lt;2 glasses of milk/day had 0.02 times the odds of meeting the EAR (95% CI: 0.01-0.02) compared to those drinking more. No significant difference was observed for BMI, though those consuming &lt;1 glass of milk/day were more likely to be obese than those consuming ≥2 glasses/day. Income and physical activity were negatively correlated with meeting the EAR.

CONCLUSION

Many children did not meet the EAR for vitamin D from dietary sources and milk consumption was an important determinant. Given trends towards a more sedentary lifestyle and limited sun exposure, we recommend prioritizing public health efforts to support dietary vitamin D intake alongside interventions to increase physical activity and reduce sedentary behaviour. Further investigation is required to determine the need for targeted strategies for obese children.

Skeletal, neuromuscular and fitness impairments among children with newly diagnosed acute lymphoblastic leukemia

This study describes skeletal, neuromuscular and fitness impairments among 109 children (median age 10 [range 4-18] years, 65.1% male, 63.3% white) with acute lymphoblastic leukemia (ALL). Outcomes were measured 7-10 days after diagnosis and compared to age- and sex-specific expected values. Associations between function and health-related quality of life (HRQL) were evaluated with logistic regression. Children with ALL had sub-optimal bone mineral density (BMD) Z-score/height (mean ± standard error: - 0.53 ± 0.16 vs. 0.00 ± 0.14, p < 0.01), body mass index percentile (57.6 ± 3.15 vs. 50.0 ± 3.27%, p = 0.02), quadriceps strength (201.9 ± 8.3 vs. 236.1 ± 5.4 N, p < 0.01), 6 min walk distance (385.0 ± 13.1 vs. 628.2 ± 7.1 m, p < 0.001) and Bruininks-Oseretsky Test of Motor Proficiency scores (23 ± 2.5 vs. 50 ± 3.4%, p < 0.01). Quadriceps weakness was associated with a 20.9-fold (95% confidence interval 2.5-173.3) increase in poor physical HRQL. Children with newly diagnosed ALL have weakness and poor endurance and may benefit from early rehabilitation that includes strengthening and aerobic conditioning.