Prevalence of vitamin D insufficiency among children in southern china: A cross-sectional survey

The vitamin D status in a Chinese osteogenesis imperfecta population and its correlation with bone metabolic markers and bone density

Objective

Studies on the baseline vitamin D levels in osteogenesis imperfecta (OI) patients before medication are scarce. This study assessed the vitamin D status of a population with OI at both the overall level and within different age groups. It correlated baseline 25-hydroxyvitamin D (25(OH)D) levels with other bone-related factors, biochemical markers, and bone density.

Patients and methods

We collected 25(OH)D levels from 95 OI patients in East China (59 under 18 years old and 36 over 18 years old). Postmenopausal women and men over 50 years old are excluded. Measurements included body indicators, biochemical markers, and bone mineral density (BMD) assessed by Dual-energy X-ray absorptiometry (DXA). Data analysis was performed using SPSS 26.0.

Results

In the overall population, among those under 18 years old, and among those over 18 years old, 87.4, 83.1, and 94.4%, respectively, were vitamin D deficient (<30 ng/mL), while 47.4, 40.7, and 58.3% had vitamin D deficiency (<20 ng/mL), respectively. In the overall population and among those under 18 years old, serum 25(OH)D levels were negatively correlated with age and parathyroid hormone (PTH) levels, and 25(OH)D levels (<10 ng/mL, 10-20 ng/mL, 20-30 ng/mL, >30 ng/mL) showed a negative correlation with BMI. In OI patients under 18 years old, serum 25(OH)D was negatively correlated with serum β-CTX levels. In adult male OI population, 25(OH)D levels were negatively correlated with OI severity (Type I, IV, III). No statistically significant correlation was found between 25(OH)D levels and BMD Z-scores.

Conclusion

This study on OI in East China reveals significant vitamin D insufficiency and deficiency in baseline levels among pediatric, adolescent and adult OI patients. It assesses the correlation of 25(OH)D levels with various influencing factors, providing crucial insights into understanding the impact of OI on vitamin D status across different age groups and aiding in better clinical management of OI patients.

Vitamin D Status among 2-18-Year-Old Romanian Pediatric Patients: A Single-Center Study

An adequate vitamin D level is essential for optimal bone mass formation during growth. The present study aimed to assess (i) the sex-specific, age-specific, and potential seasonal (spring, summer, winter) influences on the pediatric circulating levels of 25-hydroxyvitamin D (25(OH)D); (ii) determine the frequency of pediatric patients with vitamin D deficiency (VDD) or insufficiency (VDI); and (iii) quantify the association between age category, sex, and season types and susceptibility to VDD and VDI, respectively. Laboratory data were collected on serum 25(OH)D levels in children aged between 2 and 18 years (n = 1674) who underwent blood sampling following admission to a university pediatric hospital in Cluj-Napoca (Romania) between January and June 2023. VDD (<20 ng/mL) was observed in 27% of pediatric patients. Among toddlers and preschoolers (2-5 years), VDD was 11%, while it was 33% among school-aged children (6-11 years) and 39% among adolescents (12-18 years). We found a significant difference in the frequencies of vitamin D status between females and males (p = 0.006). Also, we found significant associations of vitamin D status with age categories (p < 0.0001) and seasonal variations (p = 0.03). After adjusting for season of blood collection, the multinomial logistic regression model showed that children aged 6-11 years old (adjusted OR = 7, 95% CI: (4.9, 9.4)), children aged 12-18 years old (adjusted OR = 14, 95% CI: (9.3, 19.6)), and females (adjusted OR = 1.43, 95% CI: (1.10, 1.86)) were significantly associated with higher odds of VDD. In conclusion, the study revealed a significant difference in the frequency of VDD and VDI among pediatric patients older than six years, with a significant difference according to sex and season, being more pronounced among girls and during the winter and spring seasons.

The relationship of vitamin D deficiency and childhood diarrhea: a systematic review and meta-analysis

INTRODUCTION

Vitamin D deficiency may increase the risk of childhood diarrhea. We aim to carry out a review and meta-analysis of the evidence relating vitamin D insufficiency to childhood diarrhea.

METHODS

We searched PubMed, Ovid, Scopus, and Cochrane Library (from inception to August 2022), then independently reviewed the eligibility, and read full-text reviews for selected articles. Keywords used were 'vitamin D', '25-hydroxyvitamin D', 'vitamin D deficiency', 'diarrhea', 'gastroenteritis', 'children', and 'pediatric'. The search was limited to studies only in English and with available full-text. Year limitation was not applied in our search. Unpublished trials, dissertations, preliminary reports, conference abstracts, and repositories were excluded from the study. Newcastle-Ottawa Scale was used as the risk of bias assessment tool. Meta-analysis using the random-effects model was done.

RESULTS

Out of 5,565 articles, 12 articles were included in our systematic review, however only 7 articles were eligible for meta-analysis. Meta-analysis showed a statistically significant association between vitamin D deficiency and diarrhea in children in developing countries (OR = 1.79; 95% CI = 1.15 to 2.80; p = 0.01). On the secondary outcome, the association of vitamin D deficiency and duration or recurrences of diarrhea are conflicting.

CONCLUSIONS

There is an association between vitamin D deficiency and the prevalence of diarrhea. Future studies should evaluate the causal association, the impact of vitamin D deficiency on the severity of diarrhea, and whether vitamin D deficiency treatments affects the prevalence of diarrhea.

Evaluation of the deficiency status of 25-hydroxyvitamin D and associated factors in Southwest China: A hospital-based retrospective cross-sectional analysis of a low-latitude, high-altitude, multiracial region

Vitamin D deficiency is widespread in different populations and regions worldwide and has become a global health issue. The vitamin D status of the population in the Yunnan Province of Southwest China has not been evaluated to date. Therefore, in this study, we evaluated the vitamin D status according to the serum concentrations of 25-hydroxyvitamin D (25(OH)D) in individuals of Yunnan Province, a low-latitude, high-altitude and multiracial region in China. The data on 25(OH)D concentrations from October 2012 to December 2017 were retrospectively collected and assessed using the laboratory information system from 52 950 hospital-based participants (age, 1 day-96 years; females, 73.74%). The serum concentration of 25(OH)D was evaluated using a chemiluminescent immunoassay. The analysis was stratified by sex, age, sampling season, testing year, minority, residential district, latitude, altitude and meteorological factors. Vitamin D status was classified as follows: severe deficiency: <10 ng/mL; deficiency: <20 ng/mL; insufficiency: <30 ng/mL; and sufficiency: ≥30 ng/mL. The results showed that vitamin D deficiency is highly prevalent in Yunnan Province in a hospital-based cohort, with a deficiency and severe deficiency rate of 65.1% and a sufficiency rate of 5.30%. Significantly lower vitamin D levels and sufficiency rates were observed in females than in males (20.13 ± 7.22 ng/mL vs. 17.56 ± 6.66 ng/mL and 8.20% vs. 4.20%; p < 0.01, respectively); in spring and winter (16.93 ± 6.24 ng/mL; 2.97% and 16.38 ± 6.43 ng/mL; 3.06%, respectively) than in summer and autumn (20.23 ± 7.14 ng/mL; 8.02% and 19.10 ± 6.97 ng/mL; 6.61% [p < 0.01], respectively); and in older individuals (0-6 years: 28.29 ± 13.13 ng/mL vs. >60 years: 14.88 ± 8.39 ng/mL; p < 0.01). Relatively higher vitamin D levels were observed in individuals of Yi, Zhuang, Hani, Dai, Miao and Lisu minorities and lower levels in individuals of Hui and Zang minorities compared with those of the Han nationality (p < 0.01). The mean sunlight duration, mean air temperature, maximum ultraviolet value and latitude were significantly correlated with vitamin D levels (r = -0.53, 0.60, 0.31, -0.68, respectively; p < 0.05). These results suggest that vitamin D status is influenced by sex, age, minority, latitude and some meteorological factors in areas with high and low altitudes. Hence, new public health policies, such as advice on sunshine exposure, food fortification and nutrition education, as well as the implementation of vitamin D supplementation programmes must be considered to alleviate vitamin D deficiency in Yunnan province, Southwest China.

The Impact of Vitamin D Deficiency on Infants' Health

Vitamin D is an essential nutrient that plays a vital role in bone health and musculoskeletal development. The aim of this narrative review is to present up-to-date information about the impact of vitamin D deficiency (VDD) on the health status of infants in their first year of life. Vitamin D is indispensable for skeletal growth and bone health, and emerging research suggests that it may also have significant roles in maternal and fetal health. VDD affects a large proportion of infants according to current guidelines. However, its prevalence varies depending on geographic location, skin pigmentation, and the time of year. Based on current guidelines for normal vitamin D levels and recommended daily intake, studies suggest that VDD is a global health issue with potentially significant implications for those at risk, especially infants. Our understanding of the role of vitamin D has improved significantly in the last few decades. Systematic reviews and meta-analyses investigating the effect of vitamin D on preterm birth, low birth weight, anthropometric parameters, and health outcomes such as infectious diseases in infants, have found conflicting or inconsistent results. It is important to encourage further research to fill in these knowledge gaps and develop national or global strategies that ease the burden of VDD, especially in groups at risk.

Children with severe acute malnutrition have high rates of bone resorption: A cross-sectional comparative study

Malnutrition in under-5 children (i.e., children younger than age 5 years) remains a major public health problem. Because of the reductive adaptation in children with severe acute malnutrition (SAM), changes in bone health are often subtle. We hypothesized that children with SAM have higher rates of bone resorption than bone formation, which can be assessed using bone turnover markers. In this cross-sectional comparative study, we evaluated the status of bone turnover markers, serum osteocalcin and serum tartrate-resistant acid phosphatase-5b (TRAP-5b) in under-5 children with SAM. Thirty children (6-59 months) with SAM (defined as per World Health Organization criteria) were enrolled as cases and another 30 children (age and sex matched) with normal nutritional status (weight for height -1 standard deviation [SD] to +1 SD) were enrolled for comparison of bone turnover markers. Serum TRAP-5b concentrations were significantly higher in children with SAM compared with children with normal nutritional status (mean [SD] 22.6 [15.3] vs. 11.3 [9.6], P = .009), whereas serum osteocalcin concentrations were comparable between the 2 groups (mean [SD] 40.6 [17.9] vs. 36.0 [12.5], P = .344). Frequency of hypocalcemia and vitamin D deficiency were also significantly high in children with SAM (P < .05). An inverse correlation was found between serum calcium and serum osteocalcin (r = -0.383, P < .05). Our results indicate that children with SAM have a higher bone resorption rate than children with normal nutrition status indicating compromised bone health.

Serum 25-hydroxyvitamin D status of a large Chinese population from 30 provinces by LC-MS/MS measurement for consecutive 3 years: differences by age, sex, season and province

PURPOSE

We aimed to describe the vitamin D status and its distribution in different age groups, sexes, seasons, and provinces of a large Chinese population.

METHODS

This study retrospectively analyzed 1,528,685 results of serum 25-hydroxyvitamin D (25(OH)D) in the central laboratory of KingMed Diagnostics. The samples were from the individuals aged 0-119 years old in 30 provinces of China. Serum 25(OH)D was measured by an accurate commercial liquid chromatography-tandem mass spectrometry (LC-MS/MS) method from January 2017 to December 2019. The subjects were stratified by age, sex, the season of blood collection, and the province of residence.

RESULTS

The median 25(OH)D concentration was 25.5 ng/mL (interquartile range (IQR) 18.7-32.7 ng/mL) in males and 20.8 ng/mL (IQR 14.4-28.2 ng/mL) in females. Overall, the median 25(OH)D concentration decreased with age in both males and females. Males had a 0.2-2.4 ng/mL higher median 25(OH)D concentration than females in different age groups. Vitamin D deficiency (25(OH)D < 15 ng/mL for the individuals under 14 years old; < 20 ng/mL for the individuals over 14 years old) was found in 21.3% of males and 43.6% of females. Significant seasonal variation of serum 25(OH)D concentrations was repeatedly observed in 3 years, with median concentration higher in summer (25.3 ng/mL (IQR 19.3-31.9 ng/mL)) and lower in winter (18.5 ng/mL (IQR 12.3-26.6 ng/mL)). Vitamin D status varied by province. The median 25(OH)D concentration was the highest in Hainan (31.0 ng/mL (IQR 24.9-39.2 ng/mL)) and the lowest in Qinghai (14.4 ng/mL (IQR 9.6-20.0 ng/mL)). 25(OH)D₂ was detected in 12.2% of the results, and no significant seasonal variation was observed.

CONCLUSION

In China, vitamin D deficiency is prevalent in the population participating in clinical vitamin D measurement. Age and sex differences in vitamin D levels were observed in our study. Seasonal variation and provincial differences are important aspects of serum vitamin D status. 25(OH)D₂ cannot be ignored entirely in clinical measurement practice in China.

Systematic Literature Review of the Nutrient Status, Intake, and Diet Quality of Chinese Children across Different Age Groups

There is a lack of comprehensive reports on nutrient deficiencies and dietary intake among various age groups of children in China. The objective of this review is to provide an overview of the nutrient status, intake, and diet adequacy of Chinese children (0-18 years old). PubMed and Scopus were searched for literature published between January 2010 and July 2022. A systematic review approach with a quality assessment was performed to analyze 2986 identified articles in English and Chinese. Eighty-three articles were included in the analysis. In younger children, anemia and iron and Vitamin A deficiencies remain severe public health problems, despite high Vitamin A and adequate iron intake. In older children, a high prevalence of selenium; Vitamin A and D deficiencies; and inadequate intakes of Vitamins A, D, B, C, selenium, and calcium were reported. Intakes of dairy, soybeans, fruits, and vegetables were below recommended levels. High intakes of iodine, total and saturated fat, and sodium and low dietary diversity scores were also reported. As nutritional concerns vary with age and region, future nutrition interventions should be tailored accordingly.

Serum 25-Hydroxyvitamin D Levels and Youth-Onset Type 2 Diabetes: A Two-Sample Mendelian Randomization Study

Observational studies have linked vitamin D insufficiency to pediatric type 2 diabetes (T2D), but evidence from vitamin D supplementation trials is sparse. Given the rising prevalence of pediatric T2D in all ethnicities, determining the protective role of vitamin D has significant public health importance. We tested whether serum 25-hydroxyvitamin D (25OHD) levels are causally linked to youth-onset T2D risk using Mendelian randomization (MR). We selected 54 single-nucleotide polymorphisms (SNPs) associated with 25OHD in a European genome-wide association study (GWAS) on 443,734 individuals and obtained their effects on pediatric T2D from the multi-ethnic PRODIGY GWAS (3006 cases/6061 controls). We applied inverse variance weighted (IVW) MR and a series of MR methods to control for pleiotropy. We undertook sensitivity analyses in ethnic sub-cohorts of PRODIGY, using SNPs in core vitamin D genes or ancestry-informed 25OHD SNPs. Multivariable MR accounted for the mediating effects of body mass index. We found that a standard deviation increase in 25OHD in the logarithmic scale did not affect youth-onset T2D risk (IVW MR odds ratio (OR) = 1.04, 95% CI = 0.96-1.13, p = 0.35) in the multi-ethnic analysis, and sensitivity, ancestry-specific and multivariable MR analyses showed consistent results. Our study had limited power to detect small/moderate effects of 25OHD (OR of pediatric T2D < 1.39 to 2.1). In conclusion, 25OHD levels are unlikely to have significant effects on the risk of youth-onset T2D across different ethnicities.

Association of food allergy in children with vitamin D insufficiency: a systematic review and meta-analysis

Current literature regarding the association of vitamin D insufficiency and food allergy is contradicting. The purpose of our study was to investigate this association. This is a systematic review and meta-analysis according to the PRISMA statement. PubMeD and Scopus databases were systematically searched for case-control studies investigating the association between pediatric food allergy and vitamin D insufficiency. Our search yielded 806 studies. Ten final studies were considered eligible for qualitative and quantitative analysis. Children with vitamin D insufficiency were found to have 68% more probability to present a food allergy episode (adjusted pooled OR: 1.68, 95% CI [1.25-2.27], p-value: 0.001). In their second year of life they were 4 times more likely to present a food allergy episode (adjusted pooled OR: 4.06, 95% CI [1.93-8.56], p-value: < 0.001), and 56% more probable to develop food sensitization (OR: 1.56, 95% CI [1.15-2.11], p-value: < 0.004). Children in Australia with vitamin D insufficiency were almost 4 times more likely to develop egg sensitization (adjusted OR: 3.79, 95% CI [1.19-12.08], p-value: 0.024). Children with vitamin D insufficiency were almost twice as likely to have peanut sensitization (OR: 1.96, 95% CI [1.08-3.57], p-value: 0.028).  Conclusion: Decreased maternal vitamin D levels and infant vitamin D insufficiency appear to increase the incidence of food allergies, particularly in the second year of life. To confirm this association, multicenter longitudinal studies are required. What is Known: • In newborns and young children, vitamin D deficiency and insufficiency are prevalent. • The exact role of vitamin D in atopic diseases remains controversial. What is New: • Decreased maternal vitamin D levels and infant vitamin D insufficiency appear to increase the incidence of food allergies. This association is more evident in the second year of life.

Vitamin D levels in children with cerebral palsy

PURPOSE

The aim of this study was to assess serum vitamin D levels and related factors in children with cerebral palsy (CP).

METHODS

One hundred and nineteen children with CP between the ages of 1 year to 10 years 9 months who were admitted to the children's inpatient rehabilitation unit of a tertiary rehabilitation hospital between January 1, 2017, and December 31, 2018, were included in this study. Demographic and clinical characteristics were obtained from the patient files. CP types and serum 25 hydroxyvitamin D (25OHD) levels were recorded. Gross Motor Function Classification System (GMFCS) was used to assess the functional level.

RESULTS

Mean age was 5.1±2.9 years. Forty-two (35.3%) were girls, 105 (88.3%) were spastic, and 14 (11.7%) were ataxic and mixed type CP. Mean GMFCS level was 4 (IQR:2). Thirty-one (26.1%) were getting extra liquid feed while the rest were eating a normal diet. Mean serum 25OHD level was 27.4±15.7 (3-79) ng/mL. Vitamin D levels were normal in 68 children (57.1%), whereas 36 (30.3%) had vitamin D insufficiency and 15 (12.6%) showed vitamin D deficiency. Those whose serum vitamin D levels were within a normal range had a median age of 3.8 (IQR:4.2) years. On the other hand, mean age was 6.4 (4.3) years for those with low vitamin D level (p <  0.0001). Vitamin D level was 19.8 (21.4) ng/mL in those (n = 88) who had regular diets, whereas it was 31.0 [16] ng/mL in those (n = 31) who were getting extra liquid feed (p = 0.015). There was no statistically significant correlation between vitamin D level and gender, GMFCS, CP type, season or antiepileptic drug treatment. A binary logistic regression model showed that older age and having only regular meals were significant risk factors for low vitamin D.

CONCLUSION

In this study, 42.9% of the children with CP had low vitamin D. Older children with CP or those who had regular diets were higher risk groups in terms of low vitamin D.

Large retrospective cohort study of the association between maternal 25-hydroxyvitamin D status and birth weight of neonate

BACKGROUND

The effect of maternal vitamin D levels on the birth weight of the offspring remains controversial, as the results are inconsistent between different populations. This large retrospective cohort study aimed to assess the relationship between maternal vitamin D levels and birth weight of neonates in southern China.

METHODS

Serum samples were collected from 10,586 Chinese women at 13-27 weeks of pregnancy, and the 25-hydroxyvitamin D (25(OH)D) level of the participants was assessed. Using the INTERGROWTH-21st standards, the offspring were classified into three groups based on their gestational age and birth weight, which were small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational age (LGA). The differences in vitamin D levels among the different groups were compared, and their correlation with newborn birth weight was analyzed.

RESULTS

The average maternal vitamin D concentration was 61.1 nmol/L. The 25(OH)D concentrations were 50-75 nmol/L, 25-50 nmol/L and below 25 nmol/L in 45.5%, 29.5%, and 1.6% of the participants, respectively. No significant differences were observed in the vitamin D levels between the three groups. With the increase in 25(OH)D levels, the risk of SGA and LGA tended to increase and decrease, respectively. AGA was not affected by the 25(OH)D levels. The results of the curve fitting and threshold effect analyses did not support the correlation between vitamin D levels and SGA or LGA. Based on the univariate prediction model and the model adjusted for risk factors, the area under the curve was extremely small. Thus, 25(OH)D levels are not an effective predictor of SGA and LGA.

CONCLUSIONS

Low maternal vitamin D levels were not associated with SGA or LGA.

Cohort profile: the Westlake BioBank for Chinese (WBBC) pilot project

PURPOSE

The Westlake BioBank for Chinese (WBBC) pilot cohort is a population-based prospective study with its major purpose to better understand the effect of genetic and environmental factors on growth and development from adolescents to adults.

PARTICIPANTS

A total of 14 726 participants (4751 males and 9975 females) aged 14-25 years were recruited and the baseline survey was carried out from 2017 to 2019. The pilot cohort contains rich range of information regarding of demographics and anthropometric measurements, lifestyle and sleep patterns, clinical and health outcomes. Visit the WBBC website for more information (https://wbbc.westlake.edu.cn/index.html).

FINDINGS TO DATE

The mean age of the study samples were 18.6 years for males and 18.5 years for females, respectively. The mean height and weight were 172.9 cm and 65.81 kg for males, and 160.1 cm and 52.85 kg for females. Results indicated that the prevalence of underweight in female was much higher than male, but the prevalence of overweight and obesity in female was lower than male. The mean serum 25(OH)D level in the 14 726 young participants was 22.4±5.3 ng/mL, and male had a higher level of serum 25(OH)D than female, overall, 33.5% of the participants had vitamin D deficiency and even more participants suffered from vitamin D insufficiency (58.2%). The proportion of deficiency in females was much higher than that in males (41.8 vs 16.4%). The issue of underweight and vitamin D deficiency in young people should be paid attention, especially in females. These results reflected the fact that thinness and paler skin are preferred in modern aesthetics of Chinese culture.

FUTURE PLANS

WBBC pilot is designed as a prospective cohort study and provides a unique and rich data set analysing health trajectories from adolescents to young adults. WBBC will continue to collect samples with old age.

Vitamin D can safely reduce asthma exacerbations among corticosteroid-using children and adults with asthma: a systematic review and meta-analysis of randomized controlled trials

Previous studies have failed to draw a consistent conclusion over the effect of vitamin D administration on asthma. We hypothesized that vitamin D supplementation could improve the clinical efficacy of corticosteroids in patients with asthma as measured by exacerbations, Asthma Control Test (ACT) score, and lung function in order to maintain asthma control. We searched Web of Science, PubMed, the Cochrane Library, and ScienceDirect up through January 20, 2021 for randomized controlled trials analyzing the effect of vitamin D supplementation on asthma exacerbation. Studies were limited to patients with moderate to severe asthma who were treated with corticosteroids. We identified 12 studies involving 1,543 participants in this meta-analysis. Vitamin D supplementation significantly reduced the risk of asthma exacerbation (pooled risk ratio (RR) 0.70, 95% confidence interval (CI), 0.59, 0.83; P < .05). The pooled RR of the ACT score was 0.04 (95% CI, -0.19, 0.27; P > .05). The pooled standardized mean difference in vitamin D levels was 1.07 (95% CI, 0.77, 1.38; P < .05), and in the percentage of forced expiratory volume in one second was -0.02 (95% CI, -0.13, 0.09; P > .05). The pooled RR of adverse events was 1.06 (95% CI, 0.89, 1.25; P > .05). We performed subgroup analysis and meta-regression of serum vitamin D levels but found no source of heterogeneity. Vitamin D supplementation safely reduced the rate of asthma exacerbation but did not improve ACT score or lung function among patients with asthma treated with corticosteroids.

Association between serum 25-hydroxyvitamin D concentrations and obesity in one-year-old Chinese infants

Recent studies suggested that vitamin D is linked with obesity, but evidence in infants is scarce. Therefore, we aimed to make an exploration in infants. A total of 414 infants at one year old who visited Maternity and Child Health Care Hospital of Wuxi in China were recruited. Finger-stick blood sampling was conducted in all the subjects, and serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured. Maternal characteristics during pregnancy and infantile information were collected by questionnaires or extracting from medical records. Multivariable linear models were performed to assess the relationship between 25(OH)D and body mass index (BMI), while multivariable logistic regression models were used to examine the association between 25(OH)D and obesity. Among the 414 infants, 69 (16.67%) and 81 (19.57%) infants were defined as obesity and vitamin D deficiency [25(OH)D < 50 nmol/L], respectively. The mean (SD) of 25(OH)D concentration was 68.05 (19.05) in infants without obesity, which was significantly higher than that of obese infants [60.36(18.49), p = .002]. Inverse linear relationships were observed between 25(OH)D level and BMI (β = -0.017, p = .004) as well as BMI Z-score (β = -0.010, p = .004). Furthermore, vitamin D deficiency was associated with an increased risk of obesity of infants (adjusted odds ratio = 2.74, 95% confidence interval = 1.20-6.25, with 25(OH)D ≥ 75 nmol/L as a reference). The results showed that serum 25(OH)D concentrations were significantly lower in infants with obesity, suggesting vitamin D deficiency may be an independent risk factor for obesity among one-year-old Chinese infants.

Prevalence and predictors of vitamin D deficiency in young African children

BACKGROUND

Children living in sub-Saharan Africa have a high burden of rickets and infectious diseases, conditions that are linked to vitamin D deficiency. However, data on the vitamin D status of young African children and its environmental and genetic predictors are limited. We aimed to examine the prevalence and predictors of vitamin D deficiency in young African children.

METHODS

We measured 25-hydroxyvitamin D (25(OH)D) and typed the single nucleotide polymorphisms, rs4588 and rs7041, in the GC gene encoding the vitamin D binding protein (DBP) in 4509 children aged 0-8 years living in Kenya, Uganda, Burkina Faso, The Gambia and South Africa. We evaluated associations between vitamin D status and country, age, sex, season, anthropometric indices, inflammation, malaria and DBP haplotypes in regression analyses.

RESULTS

Median age was 23.9 months (interquartile range [IQR] 12.3, 35.9). Prevalence of vitamin D deficiency using 25(OH)D cut-offs of < 30 nmol/L and < 50 nmol/L was 0.6% (95% CI 0.4, 0.9) and 7.8% (95% CI 7.0, 8.5), respectively. Overall median 25(OH)D level was 77.6 nmol/L (IQR 63.6, 94.2). 25(OH)D levels were lower in South Africa, in older children, during winter or the long rains, and in those with afebrile malaria, and higher in children with inflammation. 25(OH)D levels did not vary by stunting, wasting or underweight in adjusted regression models. The distribution of Gc variants was Gc1f 83.3%, Gc1s 8.5% and Gc2 8.2% overall and varied by country. Individuals carrying the Gc2 variant had lower median 25(OH)D levels (72.4 nmol/L (IQR 59.4, 86.5) than those carrying the Gc1f (77.3 nmol/L (IQR 63.5, 92.8)) or Gc1s (78.9 nmol/L (IQR 63.8, 95.5)) variants.

CONCLUSIONS

Approximately 0.6% and 7.8% of young African children were vitamin D deficient as defined by 25(OH)D levels < 30 nmol/L and < 50 nmol/L, respectively. Latitude, age, season, and prevalence of inflammation and malaria should be considered in strategies to assess and manage vitamin D deficiency in young children living in Africa.

Vitamin D status and its dietary and lifestyle factors in children during the first 5 years of life: A cross-sectional multicentre Jiangsu bone study

BACKGROUND

To explore the vitamin D status with its demographic and lifestyle factors including dietary, supplementation, and physical activity in 0-5 years old children.

METHODS

This was a large population-based cross-sectional multicentre study in which the children were recruited from 12 Children's Health Care Centers by a stratified cluster random-sampling method in 10 cities in Jiangsu Province, China.

RESULTS

A total number of 5289 children were investigated. The prevalence of vitamin D deficiency was 30.1%. The concentration of 25 hydroxyvitamin D was 64.0 (46.3-83.0) nmol mL^-1 after adjustment for covariates. Children with higher risk of vitamin D deficiency were more likely to be at older age, girls, survey conducted in spring, location in southern Jiangsu province, residence in urban, outdoor activity < 2 h day^-1 (all p < 0.05). Moreover, those with lower risk were more likely to be the number of parity ≥ 2 times, vitamin D supplementation from birth to 6 months, the initial time of vitamin D supplementation after birth ≤ 1 months, vitamin D and calcium supplementation in the last 3 months, and dose of vitamin D supplementation > 400 IU day^-1 (all p < 0.05). Children with preferences for sweets, meat consumption > 150.0 g day^-1 , milk consumption < 250 mL day^-1 , time of sleeping < 10 h day^-1 had higher risks of vitamin D deficiency. However, these relationships were affected by demographics.

CONCLUSIONS

Vitamin D status during the first five years of life was suboptimal and was associated with demographic and lifestyle determinants including milk, meat, sweets, vitamin D and calcium supplementation, sleeping and outdoor activity.

Effect of Vitamin D Supplementation in Early Life on Children's Growth and Body Composition: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Vitamin D deficiency during pregnancy or infancy is associated with adverse growth in children. No systematic review has been conducted to summarize available evidence on the effect of vitamin D supplementation in pregnancy and infancy on growth and body composition in children. Objective: We aim to summarize the available evidence on the effect of vitamin D supplementation in pregnancy and infancy on child growth and body composition. Method: A systematic review and meta-analysis were performed on the effects of vitamin D supplementation during early life on children’s growth and body composition (bone, lean and fat). A literature search of randomized controlled trials (RCTs) was conducted to identify relevant studies on the effects of vitamin D supplementation during pregnancy and infancy on children’s body composition (bone, lean and fat) in PubMed, EMBASE and Cochrane Library from inception to 31 December 2020. A Cochrane Risk Assessment Tool was used for quality assessment. The comparison was vitamin D supplementation vs. placebo or standard care. Random-effects and fixed-effect meta-analyses were conducted. The effects are presented as mean differences (MDs) or risk ratios (RRs) with 95% confidence intervals (CIs). Results: A total of 3960 participants from eleven randomized controlled trials were eligible for inclusion. Vitamin D supplementation during pregnancy was associated with higher triceps skinfold thickness (mm) (MD 0.33, 95% CI, 0.12, 0.54; I² = 34%) in neonates. Vitamin D supplementation during pregnancy or infancy was associated with significantly increased length for age z-score in infants at 1 year of age (MD 0.29, 95% CI, 0.03, 0.54; I² = 0%), and was associated with lower body mass index (BMI) (kg/m²) (MD −0.19, 95% CI −0.34, −0.04; I² = 0%) and body mass index z-score (BMIZ) (MD −0.12, 95% CI −0.21, −0.04; I² = 0%) in offspring at 3–6 years of age. Vitamin D supplementation during early life was not observed to be associated with children’s bone, lean or fat mass. Conclusion: Vitamin D supplementation during pregnancy or infancy may be associated with reduced adiposity in childhood. Further large clinical trials of the effects of vitamin D supplementation on childhood body composition are warranted.

Prevalence of vitamin D status and its association with overweight or obesity in a population of Colombian children and adolescents

The present study aimed to estimate the prevalence of 25-OH-D status (insufficiency and deficiency) in children and adolescents residing in Bucaramanga, Colombia and to determine its association with excess weight. A case-control study was nested in the SIMBA II cohort in children and adolescents between the ages of 11 and 20 years old. Cases were defined as those children and adolescents with overweight or obesity. The control group was composed of children and adolescents from the same population sample with similar sociodemographic and economic characteristics but without overweight or obesity diagnosis. 25-hydroxyvitamin D (25-OH-D) was quantified in serum using a chemiluminescent microparticle immunoassay. Logistic regression models were used to assess the association between vitamin D status and overweight or obesity adjusted for the main confounding variables. A total of 494 children and adolescents cases were 138 (52⋅17% boys and 47⋅83% girls; median age 16⋅0 [Q1 15; Q3 18]). The median BMI S-Score minors age in the cases was 1⋅36 [Q1 1⋅06; Q3 2⋅00] and BMI (kg/m2) 28⋅0 [Q1 26⋅2; Q3 30⋅8]. The prevalence of vitamin D in the cases was deficiency 16⋅67%, insufficiency 57⋅25%, sufficiency 26⋅09. 25-OH-D insufficiency was associated with overweight or obesity after adjusting for the main confounding variables (OR 1⋅73; 95% CI 1⋅05-2⋅84). Our study concludes that the 25-OH-D insufficiency is common in children and adolescents in Bucaramanga, Colombia, and it was associated with overweight or obesity.

Prevalence of vitamin D deficiency and insufficiency among 460,537 children in 825 hospitals from 18 provinces in mainland China

This study was conducted to estimate the 25-hydroxyvitamin D (25 (OH)D) levels and explore factors related to vitamin D deficiency/insufficiency. This was a multicenter, hospital-based, cross-sectional observational study. Children admitted to hospitals for health examination were included for vitamin D measurement and the 25(OH)D concentration results were categorized into 3 groups: deficiency (<30 nmol/L), insufficiency (30-50 nmol/L), and sufficiency (>50 nmol/L). Four lakh sixty thousand five hundred thirty-seven children in 825 hospitals from 18 provinces participated in this study. The prevalence of vitamin D deficiency, insufficiency, and sufficiency were 6.69%, 15.92%, and 77.39%, respectively. Vitamin D deficiency was the most severe in the central region, followed by the north, and southwest regions; however, data for the western region were lacking.Logistic regression showed that vitamin D status was worse in girls, newborns, and those visiting the hospital in the winter. In conclusion, the prevalence of vitamin D deficiency is high among Chinese children and adolescents. Studies on population estimates, cost-effective screening strategies, and interventions for high-risk cases are needed.

<p>Associations Between Serum 25-Hydroxyvitamin D Levels and Thyroid Function Parameters in Previously Healthy Children Aged 6 to 24 Months</p>

Purpose

Vitamin D deficiency has been linked to overt thyroid diseases. Data on the effects of vitamin D status on thyroid function in children are less examined. The goal of the present study was to explore the association between serum 25-hydroxyvitamin D [25(OH)D] levels and thyroid function parameters in early childhood.

Patients and Methods

This was a cross-sectional study involving record-linkage of children’s data of routine health check-ups for promoting early childhood development at Guangdong Women and Children’s Hospital; 2869 children aged 6–24 months were included from January 2015 to May 2017. Serum 25(OH)D, thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) levels were measured using the electrochemiluminescence immunoassay.

Results

The study population had a mean serum 25(OH)D level of 79.7 ± 28.1 nmol/L and 12.5% vitamin D deficiency and 36.0% insufficiency rates. The rates of thyroid dysfunctions detected were 2.9% hypothyroidism, 4.2% subclinical hypothyroidism, 0.9% hyperthyroidism, and 1.7% subclinical hyperthyroidism among the previously healthy children aged 6 to 24 months. Serum 25(OH)D levels had no significant correlation with TSH (r = 0.022, P = 0.236), FT3 (r = 0.014, P = 0.440) and FT4 (r = −0.059, P = 0.056) levels. No significant difference in the levels of thyroid hormones was found between the different quartiles of 25(OH)D level. Vitamin D deficiency [25(OH)D < 50 nmol/L] was associated with hypothyroidism (adjusted odds ratio = 2.16, 95% confidence interval: 1.18–3.94) but not with subclinical hypothyroidism, hyperthyroidism, and subclinical hyperthyroidism.

Conclusion

Vitamin D deficiency is slightly associated with hypothyroidism. No associations were found between serum 25(OH)D levels and thyroid-related measures (TSH, FT3, and FT4) in previously healthy children aged 6–24 months.

Vitamin D Status in Pregnant Women in Southern China and Risk of Preterm Birth: A Large-Scale Retrospective Cohort Study

Background

The influence of maternal vitamin D on pregnancy outcomes, including preterm birth (PTB), is unclear due to different experimental designs and study populations (patient race and sample size) of previous studies. We aimed to investigate the relationship between 25-hydroxyvitamin D (25[OH] D) levels and PTB among pregnant women in southern China.

Material/Methods

A total of 11 641 pregnant women were retrospectively enrolled between January 2016 and April 2019. Vitamin D concentrations were evaluated by electrochemiluminescence immunoassay. Logistic regression analysis was used to analyze the association between vitamin D and PTB.

Results

The average 25(OH) D concentration was 59.3±21.5 nmol/L; 34.8% of patients were vitamin D deficient, 43.0% were vitamin D insufficient (25[OH] D <50 nmol/L and 50–74.9 nmol/L, respectively). In total, 3.6% of newborns were born prematurely. Comparing the pre-term and full-term groups, 45.7% versus 42.9% and 29.8% versus 35% were vitamin D deficient and insufficient, respectively These differences were not significant (P>0.05). However, the mean vitamin D status was significantly different between the pre-term and full-term groups (61.3±21.3 and 59.1±21.5 nmol/L, respectively). No association was found between vitamin D deficiency/insufficiency and PTB in unadjusted or adjusted models, compared with vitamin D sufficiency (adjusted odds ratio, 1.016; 95% confidence interval, 0.794–1.301 and 0.842; 0.641–1.106, respectively).

Conclusions

Low maternal 25(OH) D levels are common in southern China. However, low vitamin D status in pregnant women appears to be unrelated to PTB. Measuring vitamin D level alone is therefore not sufficient to predict PTB.

Serum vitamin D level is inversely associated with liver fibrosis in post Kasai's portoenterostomy biliary atresia patients living with native liver

Objective

This study aims to investigate the association of serum vitamin D (VD) levels with the severity of liver fibrosis (LF) in post Kasai’s portoenterostomy biliary atresia (PKBA) patients living with their native liver.

Methods

In this cross-sectional study, carried out in a tertiary Children’s Hospital in Taipei, Taiwan, PKBA patients living with their native liver were enrolled. Liver biochemistry data, serum 25-hydroxyvitamin D (25-OHVD), acoustic radiation force impulse (ARFI), and scores of Pediatric Quality of Life questionnaire (PedsQL) were collected.

Results

All the enrolled 33 PKBA patients (36.4% males), aged 1–23 years, possessed 25-OHVD less than 30ng/ml. An inverse correlation was detected between serum 25-OHVD and ARFI (r² = 0.175; p = 0.024). We selected a cutoff value of 23ng/mL to divide PKBA patients into two groups, as the p-value was the most significant at this point when comparing the median ARFI of two groups (p = 0.003). Ten (30.3%) had 25-OHVD≥23ng/ml (HVD group), whereas 23(69.7%) had 25-OHVD<23ng/ml (LVD group). HVD group had lower ARFI (1.13m/s vs. 1.52m/s, p = 0.003), lower aspartate transaminase (AST) (29U/L vs. 64U/L, p = 0.033), and higher scores of self-reported health-related quality of life in psychosocial functioning (86.7 vs. 77.1, p = 0.047) than LVD group.

Conclusion

VD levels are inversely associated with severity of LF in PKBA patients with native liver.

Dietary Supplement Use Among Chinese Primary School Students: A Cross-Sectional Study in Hunan Province

Dietary supplement use is increasing globally, especially among children. However, few studies have been conducted to examine dietary supplement use among Chinese children. The aim of this study was to examine the prevalence of dietary supplement use and the associated factors in primary school students. A cross-sectional study was conducted in four primary schools in Hunan province, China. A total of 706 Chinese parents/caregivers of school children aged 6–12 years old were enrolled. Self-administrated questionnaires were used to collect information about the children’s dietary supplement use, and their socio-demographic characteristics. The prevalence of dietary supplement use in primary school students was 20.4%. Calcium (16.7%), vitamin C (9.2%), and vitamin D (8.5%) were the most commonly used types of dietary supplement. The main reasons for parents/caregivers to purchase dietary supplements for their children were immunity improvement (43.6%), and for growth promotion (36.5%). Some caregivers (26.4%) purchased dietary supplements online, including from dubious or unknown sellers. However, 37.5% of caregivers did not receive formal guidance on supplementation even if they purchased their supplements through formal channels. Parents/caregivers were unclear about the appropriate choices for children’s dietary supplement use. Guidelines and counseling regarding dietary supplements for children may be helpful in public health work.