Vitamin D deficiency and anemia risk in children: a review of emerging evidence

Association between anaemia and vitamin D insufficiency among 6- to 12-month-old infants: implications for clinical practice

BACKGROUND

Anaemia and vitamin D insufficiency (VDI) are among the most common nutritional problems. Anaemia screening is routinely performed; however, screening for VDI is not usually recommended.

OBJECTIVES

To study the association between anaemia and VDI and identify the risk factors for VDI.

METHODS

We conducted a cross-sectional study of 120 infants aged 6-12 months attending a well-child clinic at Songklanagarind Hospital between December 2020 and November 2021. Sociodemographic data and 24-h food records were also collected. Blood samples were obtained for complete blood count and 25-hydroxyvitamin D [25(OH)D] levels. Logistic regression analysis was used to determine risk factors for VDI.

RESULTS

The mean 25(OH)D level was 22.2 ± 8.9 ng/mL in anaemic infants and 27.2 ± 9.6 ng/mL in non-anaemic infants (P value 0.01). The median (IQR) Hb level was 11.1 g/dL (10.3, 11.4) in the VDI group and 11.4 g/dL (11, 12.1) in the non-VDI group (P value 0.002). The proportion of breastfed infants was higher in infants with anaemia (80%) (P < 0.001) and VDI (85.3%) (P < 0.001). Sunlight exposure <15 min/day (odds ratio [OR] 3.84; 95% confidence interval [CI]: 1.23-12.00; P = 0.020) was a risk factor, and vitamin D intake (OR 0.37; 95% CI: 0.20-0.74; P = 0.004) was a protective factor for VDI.

CONCLUSION

Infants with anaemia, short duration of sunlight exposure, breastfeeding, low vitamin D intake, and low iron intake were more likely to be vitamin D insufficient. However, after adjustment in the multivariate analyses, only sunlight exposure and vitamin D intake were significantly associated with vitamin D insufficiency.

Iron Deficiency and Vitamin D Deficiency Are Associated with Sleep in Females of Reproductive Age: An Analysis of NHANES 2005-2018 Data

BACKGROUND

Iron and vitamin D deficiencies have been implicated in sleep disturbance. Although females are more susceptible to these deficiencies and frequently report sleep-related issues, few studies have examined these associations in females.

OBJECTIVE

This study investigates the association of iron and vitamin D deficiencies on sleep in a nationally representative sample of females of reproductive age.

METHODS

We used 2 samples of 20-49-y-old non-pregnant females from National Health and Nutrition Examination Survey (NHANES) 2005-2008 (N = 2497) and NHANES 2005-2010 and 2015-2018 (N = 6731) to examine the associations of iron deficiency (ID), iron deficiency anemia (IDA), vitamin D deficiency (VDD), vitamin D inadequacy (VDI), and the joint association of both deficiencies with sleep duration, latency, and quality. Sleep outcomes were measured using a self-reported questionnaire. We used the body iron model based on serum ferritin and serum soluble transferrin receptor to identify ID, along with hemoglobin to identify IDA cases. In addition, 25-hydroxyvitamin D levels were used to determine VDD and VDI cases. Logistic regression was used to evaluate these associations, adjusting for potential confounders. In addition, we assessed the multiplicative and additive interactions of both deficiencies.

RESULTS

ID and IDA were associated with poor sleep quality, with 1.42 [95% confidence interval (CI): 1.02, 2.00)] and 2.08 (95% CI: 1.29, 3.38) higher odds, respectively, whereas VDD and VDI were significantly associated with short sleep duration, with 1.26 (95% CI: 1.02, 1.54) and 1.22 (95% CI: 1.04, 1.44) higher odds, respectively. Subjects with both nutritional deficiencies had significantly higher odds of poorer sleep quality compared with subjects with neither condition. For sleep quality, a significant multiplicative interaction was observed between ID and VDD (P value = 0.0005). No associations were observed between study exposures and sleep latency.

CONCLUSIONS

Among females of reproductive age, iron and vitamin D deficiencies are associated with sleep health outcomes. The potential synergistic effect of both deficiencies warrants further assessment.

HAART induced inflammation, toxicity and its determinants among HIV positive children in Addis Ababa, Ethiopia

Background

Highly Active Antiretroviral therapy (HAART) plays significant role in reduction of mortality among children infected with HIV. Despite the inevitable impact of HAART on inflammation and toxicity, there is limited evidence on its impact among children in Ethiopia. Moreover, evidence on contributing factors to toxicity has been poorly described. Hence, we evaluated HAART induced inflammation and toxicity among children taking HAART in Ethiopia.

Method

This cross-sectional study was conducted among children (<15 years old) taking HAART in Ethiopia. Stored plasma samples and secondary data from a previous study on HIV-1 treatment failure were used for this analysis. By 2018, a total of 554 children were recruited from randomly selected 43 health facilities in Ethiopia. The different levels of liver (SGPT), renal (Creatinine) and hematologic toxicity (Hemoglobin) toxicity were assessed using established cut-off value. Inflammatory biomarkers (CRP and vitamin-D) were also determined. Laboratory tests were done at the national clinical chemistry laboratory. Clinical and baseline laboratory data were retrieved from the participant's medical record. Questionnaire was also administered to study guardians to assess individual factors to inflammation and toxicity. Descriptive statistics was used to summarize the characteristics of the study participants. Multivariable analysis was conducted and considered significant at P < 0.05.

Result

Overall 363 (65.6%) and 199 (36%) of children taking HAART in Ethiopia developed some level of inflammation and vitamin-D in-sufficiency, respectively. A quarter of the children 140 (25.3%) were at Grade-4 liver toxicity while renal toxicity were 16 (2.9%). A third 275 (29.6%) of the children also developed anemia. Children who were on TDF+3 TC + EFV, those who were not virally suppressed and children with liver toxicity were at 17.84 (95%CI = 16.98, 18.82), 2.2 (95%CI = 1.67, 2.88) and 1.20 (95%CI = 1.14, 1.93) times risk of inflammation, respectively. Children on TDF+3 TC + EFV, those with CD4 count of <200 cells/mm³ and with renal toxicity were at 4.10 (95%CI = 1.64, 6.89), 2.16(95%CI = 1.31, 4.26) and 5.94 (95%CI = 1.18, 29.89) times risk of vitamin-D in-sufficiency, respectively. Predictors of liver toxicity were history of HAART substitution (AOR = 4.66; 95%CI = 1.84, 6.04) and being bedridden (AOR = 3.56; 95%CI = 2.01, 4.71). Children from HIV positive mother were at 4.07 (95%CI = 2.30, 6.09) times risk of renal toxicity while the different type of HAARTs had different level of risk for renal toxicity AZT+3 TC + EFV (AOR = 17.63; 95%CI = 18.25, 27.54); AZT+3 TC + NVP (AOR = 22.48; 95%CI = 13.93, 29.31); d4t+3 TC + EFV (AOR = 4.34; 95%CI = 2.51, 6.80) and d4t+3 TC + NVP (AOR = 18.91; 95%CI = 4.87, 27.74) compared to those who were on TDF+3 TC + NVP. Similarly, children who were on AZT+3 TC + EFV were at 4.92 (95%CI = 1.86, 12.70) times risk of anemia compared to those who were on TDF+ 3 TC + EFZ.

Conclusion

The high level of HAART induced inflammation and liver toxicity among children calls for the program to consider safer regimens for pediatric patients. Moreover, the high proportion of vitamin-D in-sufficiency requires program level supplement. The impact of TDF+3 TC + EFV on inflammation and vitamin-D deficiency calls for the program to revise this regimen.

Analysis of hot trends in research on the association between vitamin D and cardiovascular disease

Objective

Vitamin D deficiency is the most common nutrient deficiency. Numerous studies suggest that vitamin D is an independent risk factor for cardiovascular disease. The objective is to visualize the research hotspots and evolution trends of the correlation between vitamin D and cardiovascular disease by using multivariate statistics and social network analysis techniques and to compare adult research with that of children in this field.

Methods

(Vitamin D [MeSH Major Topic]) AND (cardiovascular disease [MeSH Major Topic]) were retrieved from the PubMed database by time period. The bibliographic items co-occurrence matrix builder (BICOMB) was adopted to extract high-frequency subject terms and establish the core subject term co-occurrence matrix. With the Netdraw function of Ucinet 6.0 software, the social network of core subject terms was completed.

Results

Before 2010, there was a slow increase in the number of research papers covering all age groups in this field (157, 54, 84, and 211 papers were published in stages 1-4, respectively). From 2010 to 2020, there were 1,423 papers retrieved, showing a significantly increased research heat. The overall development trend of the research on the association between vitamin D and cardiovascular disease in children is similar to that in all age groups. From 2010 to 2020, 122 related papers were published (while before 2009, there were only 43 papers in all), presenting a good overall development trend. The social network analysis of core subject terms showed gradually increased correlations between research hotspots, from the early studies limited on the physiological function of vitamin D in cardiovascular diseases, to the role of vitamin D in the comorbidities of various cardiovascular diseases and its value as an intervention measure. Researches on the association between vitamin D and cardiovascular disease has a good overall development trend. Study of the mechanisms and the role of vitamin D in the common co-morbidities of cardiovascular disease and its therapeutic value will be the focus of future research.

Effects of vitamin D prophylaxis on oral irontreatments of iron deficiency anemia

BACKGROUND

Iron deficiency anemia causes a decrease in immune response to infections, physical working capacity and response to metabolic stress. It also causes behavioral, perceptual and cognitive disorders. Therefore, as soon as iron deficiency anemia is diagnosed, it should be treated immediately. In this study, it was investigated retrospectively whether there was a difference in treatment efficacy between the administration of oral ferrous or ferric iron and vitamin D at the same time and at different time.

METHODS

A total of sixty patients under 1 year who attended the pediatrics outpatient clinic for pale and diagnosed with iron deficiency anemia. Patients were randomly divided into 4 groups. Anemia was defined as hemoglobin below <2 SD according to age and gender. Iron deficiency was definied with serum iron, iron-binding capacity, ferritin and transferin saturation below the range for age and gender appropriates. All patients were seen at the outpatient clinic for 1st, 3rd month of the treatment.

RESULTS

There were statistically significant differences between the groups in terms of increase in Hb values according to time (1^st month, 3^rd month, 1^st and 3^rd month). There was no statistically significant difference between the groups in terms of the recovery of anemia after treatment.

CONCLUSIONS

It was concluded that iron treatment in babies with iron deficiency anemia is not affected by the administration of vitamin D prophylaxis at the same time or at different times, and therefore both treatments can be administered at the same time to increase drug compliance.

HEMATOLOGICAL INDICES RELATED TO VITAMIN D DEFICIENCY IN OBESE CHILDREN

Introduction

Vitamin D is involved in differentiation and induction of erythropoiesis in bone marrow cells.

Aim

We compared the serum 25(OH) vitamin D level in obese children versus control and found correlations between vitamin D level and hematological indices in obese children.

Materials and methods

25 overweight and obese patients and 15 normal weight children were enrolled in an observational study .

Results

In obese children, the serum level of 25(OH) vitamin D was significantly (p<0.04) lower (20.60 ng/mL) compared with the value from normal weight ones (25.63 ng/mL) and the body fat percentage BFP was higher. We found a positive correlation (r=0.44, p<0.05) between serum vitamin D and hemoglobin level and a negative one between serum vitamin D and the number of platelets (r= -0.43, p<0.05). Also, the serum iron was at the lower normal limit in the obese children and negatively correlated with the percent of the body fat (r= -0,62, p<0.05).

Conclusion

Obese children have vitamin D deficiency. The hemoglobin level and the number of platelets are correlated with the serum level of 25(OH) vitamin D. Supplements with vitamin D may have pleiotropic effects, including those on bone marrow activity.

Is There An Association Between Vitamin B12 Level and Vitamin D Status in Children?

Vitamin B12 (vit B12) or cobalamin is a water-soluble vitamin that acts as a coenzyme and is effective in the formation of a healthy nervous system and erythrocytes. In its deficiency, except fatigue and weakness, may cause serious signs and symptoms such as macrocytic anemia, cognitive-developmental delay, irreversible neurological damage. In this study, hemoglobin, leukocyte, thrombocyte, iron, iron-binding, ferritin, and vit B12 levels were evaluated retrospectively during the routine controls of 689 children 5 to 18 years old without any complaints. In addition, the relationship between serum 25-Hydroxyvitamin D (vit D) levels and vit B12 levels, which were evaluated in 487 of the cases, was investigated. Vit B12 deficiency was diagnosed in a total of 160 (23.2%) cases, 99 (24.4%) girls and 61 (21.4%) boys. Vit B12 level was significantly lower in children over 12 years old. Vitamin D deficiency was found to be 49.3% in 487 cases and was significantly higher in the group under 12 years and girls. The frequency of anemia was 7.2% in this group. There was a significant relationship between vit D deficiency and vit B12 deficiency. In conclusion, vit B12 deficiency is common in school-age children, especially in the adolescent age group. It should be known that vit D deficiency may also be present in vit B12 deficiency cases. More comprehensive studies are needed to reveal the relationship between B12 and vit D deficiency.

Vitamin D Effects on Selected Anti-Inflammatory and Pro-Inflammatory Markers of Obesity-Related Chronic Inflammation

BACKGROUND

Obesity is related to changes in adipokine secretion, activity of adipose tissue macrophages, helper T cells, and regulatory T cells. It has been confirmed that vitamin D has potent anti-inflammatory properties. It contributes to reduction in pro-inflammatory mediators and an increase in anti-inflammatory cytokines. There is also evidence that vitamin D could decrease C-reactive protein (CRP) and affect selected haematological indices.

AIM OF THE STUDY

We aimed to evaluate the effect of vitamin D on interleukin (IL)-10, IL-17, CRP, blood leukocyte profile, and platelet (PLT) count in overweight and obese children before and after six months of vitamin D supplementation.

MATERIAL AND METHODS

The study group consisted of 67 overweight and obese children aged 9.08-17.5 years. The control group included 31 normal weight peers age- and sex-matched. None of the studied children had received vitamin D supplementation before the study. Data were analyzed at baseline and after vitamin D supplementation.

RESULTS

The study group had lower baseline 25(OH)D (p<0.001) and higher white blood cell (WBC) (p=0.014), granulocyte (p=0.015), monocyte (p=0.009) and CRP (p=0.002) compared to the control group. In the study group, vitamin D levels were related negatively to nutritional status. Leukocyte profile parameters, PLT, CRP, IL-10 or IL-17 were not related to baseline 25(OH)D. Baseline IL-17 levels correlated with monocytes (R= 0.36, p=0.003) independently on 25(OH)D deficit. In children with vitamin D <15ng/ml, the baseline 25(OH)D was related to CRP (R=-0.42, p=0.017). After six months of vitamin D supplementation, we noticed a decrease in CRP levels (p=0.0003). Serum 25(OH)D correlated with IL-10 in that period (R=0.27, p=0.028). Moreover, we noticed that IL-10 correlated with monocyte (R=-0.28, p=0.023). We did not find any significant associations between 25(OH)D and leukocyte profile parameters, PLT, or IL-17. The multivariable stepwise regression analysis identified IL-10 as the parameter positively associated with 25(OH)D.

CONCLUSIONS

Our study confirmed beneficial effects of vitamin D supplementation in overweight and obese paediatric populations. Vitamin D intake seems to exert its anti-inflammatory effect mainly via decreasing the CRP level and protecting stabile values of IL-10, rather than its impact on pro-inflammatory factors such as lL-17 and leukocyte profile parameters.

Analysis of Development Trends of the Research Hotspots of Vitamin D in Children

OBJECTIVE

Using multivariate statistics and social network analysis techniques, we present a realistic and intuitive visualization of the research hotspots and development trends of vitamin D in children.

METHODS

The Medical Subject Headings (MeSH) term "vitamin D" was used to search all the publications (the study subjects were 0-18 years old) included in PubMed by time period. The subject terms for each development stage were extracted, the high-frequency subject terms were extracted using the Bibliographic Items Co-occurrence Matrix Builder (BICOMB), and a core subject term co-occurrence matrix was established. The Netdraw function of Ucinet 6.0 software was used to complete the social network drawing of the core subject term co-occurrence matrix to form a co-word network diagram composed of core subject terms.

RESULTS

Prior to 1979, there were 890 papers with 1,899 core subject terms; from 2010 to 2020, there were 3,773 papers with 12,682 core subject terms. Before 1979, the research direction of vitamin D in children focused on vitamin D in the classical regulation of calcium and phosphorus metabolism. From 1980 to 1989, studies focused on vitamin D metabolites and therapeutic drugs such as "calcitriol" and "calcifediol." From 1990 to 1999, studies focused on "calcitriol" and its association with "psoriasis," "chronic renal failure," and "dermatological drugs." From 2000 to 2009, studies focused on "vitamin D" and "vitamin D deficiency." From 2010 to 2020, studies focused on "vitamin D₃" and its association with "vitamins," "bone mineral density protectants," "asthma," "obesity," "pregnancy complications" and "fetal blood."

CONCLUSION

Since 2010, the research direction of vitamin D in children has been growing rapidly, and the overall development trend is good. Studies extend from the study of the skeletal effect of vitamin D to the study of its extraskeletal effect and the investigation of mechanisms of its association with related diseases.

Gender difference in the relationship between anemia and vitamin D in Korean adults: the fifth Korea National Health and Nutrition Examination Survey

This study was conducted to assess the relationship between vitamin D deficiency and anemia, by gender, in Korean adults. The data of 16,060 adults were analyzed (men, 6,840; premenopausal women, 4,916; postmenopausal women, 4,340) from the fifth Korean National Health and Nutrition Examination Survey (KNHANES V) (2010–2012). There were several key findings. First, after adjusting for related variables, the odds ratio (OR) of anemia [hemoglobin (Hb) <13 g/dl in men or Hb <12 g/dl in women] using the vitamin D normal group {25-hydroxyvitamin [25(OH)D] ≥15.0 ng/ml} as reference, was significant for the vitamin D deficient group [25(OH)D <15.0 ng/ml] in the overall population [OR, 1.310; 95% confidence interval (CI), 1.168–1.470]. Second, the OR of anemia, using the vitamin D normal group as reference, was significant for the vitamin D deficient group in premenopausal women (OR, 1.293; 95% CI, 1.105–1.513). However, vitamin D deficiency in the vitamin D normal group in men (OR, 1.093; 95% CI, 0.806–1.484) and postmenopausal women (OR, 1.130; 95% CI, 0.906–1.409) was not significant. In conclusion, Vitamin D deficiency is positively associated with anemia in premenopausal women, but not in men and postmenopausal women.

Parenteral iron therapy and phosphorus homeostasis: A review

Phosphorus has an essential role in cellular and extracellular metabolism; maintenance of normal phosphorus homeostasis is critical. Phosphorus homeostasis can be affected by diet and certain medications; some intravenous iron formulations can induce renal phosphate excretion and hypophosphatemia, likely through increasing serum concentrations of intact fibroblast growth factor 23. Case studies provide insights into two types of hypophosphatemia: acute symptomatic and chronic hypophosphatemia, while considering the role of pre‐existing conditions and comorbidities, medications, and intravenous iron. This review examines phosphorus homeostasis and hypophosphatemia, with emphasis on effects of iron deficiency and iron replacement using intravenous iron formulations.

Vitamin D-Resistant Rickets Diagnostics and Treatment Challenges at Muhimbili National Hospital, Tanzania

Introduction. Rickets is softening of bones caused by defective mineralization of the cartilage in the epiphyseal growth plate, causing widening of the ends of long bones, growth retardation, and skeletal deformities in children. It can be classified into calciopenic and phosphopenic, each type with various subclasses. Case Presentations. We presented 2 cases, first of a 1 year and 4-month-old male, with a history of recurrent episodes of cough for 8 months and bowing of the legs 6 months prior to admission. Clinical and laboratory investigation was suggestive of vitamin D-dependent rickets, and he started vitamin D treatment with minimal response. The second case is of a 4 years and 7-month-old male who presented with developmental delay, poor weight gain, and recurrent chest infection and worsening of bone pain since 9 months of age. Laboratory investigation was suggestive of phosphopenic rickets, and he was started on treatment at 9 months of age with little improvement and at 4 years, he sustained multiple fractures and succumbed to severe respiratory tract infection and died at 4 years and 7 months of age.

CONCLUSION

Rickets pose a diagnostic and treatment challenge in resource-limited countries, and clinical judgment and early initiation of treatment are important.