Vitamin D insufficiency among hospitalised children in the Northern Territory

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 Unpublished trials, dissertations, preliminary reports, conference abstracts, and repositories were excluded from the study.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.

Vitamin D as an adjunct to antibiotics for the treatment of acute childhood pneumonia

BACKGROUND

Children with acute pneumonia may be vitamin D deficient. Clinical trials have found that prophylactic vitamin D supplementation decreases children's risk of developing pneumonia. Data on the therapeutic effects of vitamin D in acute childhood pneumonia are limited. This is an update of a Cochrane Review first published in 2018.

OBJECTIVES

To evaluate the efficacy and safety of vitamin D supplementation as an adjunct to antibiotics for the treatment of acute childhood pneumonia.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and two trial registries on 28 December 2021. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared vitamin D supplementation with placebo in children (aged one month to five years) hospitalised with acute community-acquired pneumonia, as defined by the World Health Organization (WHO) acute respiratory infection guidelines. For this update, we reappraised eligible trials according to research integrity criteria, excluding RCTs published from April 2018 that were not prospectively registered in a trials registry according to WHO or Clinical Trials Registry - India (CTRI) guidelines (it was not mandatory to register clinical trials in India before April 2018).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and extracted data. For dichotomous data, we extracted the number of participants experiencing the outcome and the total number of participants in each treatment group. For continuous data, we used the arithmetic mean and standard deviation (SD) for each treatment group together with number of participants in each group. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

In this update, we included three new trials involving 468 children, bringing the total number of trials to seven, with 1601 children (631 with pneumonia and 970 with severe or very severe pneumonia). We categorised three previously included studies and three new studies as 'awaiting classification' based on the research integrity screen. Five trials used a single bolus dose of vitamin D (300,000 IU in one trial and 100,000 IU in four trials) at the onset of illness or within 24 hours of hospital admission; one used a daily dose of oral vitamin D (1000 IU for children aged up to one year and 2000 IU for children aged over one year) for five days; and one used variable doses (on day 1, 20,000 IU in children younger than six months, 50,000 IU in children aged six to 12 months, and 100,000 IU in children aged 13 to 59 months; followed by 10,000 IU/day for four days or until discharge). Three trials performed microbiological diagnosis of pneumonia, radiological diagnosis of pneumonia, or both. Vitamin D probably has little or no effect on the time to resolution of acute illness (mean difference (MD) -1.28 hours, 95% confidence interval (CI) -5.47 to 2.91; 5 trials, 1188 children; moderate-certainty evidence). We do not know if vitamin D has an effect on the duration of hospitalisation (MD 4.96 hours, 95% CI -8.28 to 18.21; 5 trials, 1023 children; very low-certainty evidence). We do not know if vitamin D has an effect on mortality rate (risk ratio (RR) 0.69, 95% CI 0.44 to 1.07; 3 trials, 584 children; low-certainty evidence). The trials reported no major adverse events. According to GRADE criteria, the evidence was of very low-to-moderate certainty for all outcomes, owing to serious trial limitations, inconsistency, indirectness, and imprecision. Three trials received funding: one from the New Zealand Aid Corporation, one from an institutional grant, and one from multigovernment organisations (Bangladesh, Sweden, and UK). The remaining four trials were unfunded.

AUTHORS' CONCLUSIONS

Based on the available evidence, we are uncertain whether vitamin D supplementation has important effects on outcomes of acute pneumonia when used as an adjunct to antibiotics. The trials reported no major adverse events. Uncertainty in the evidence is due to imprecision, risk of bias, inconsistency, and indirectness.

Comparison of Profiles of First Nations and Non-First Nations Children With Bronchiectasis Over Two 5-Year Periods in the Northern Territory, Australia

BACKGROUND

Although the burden of bronchiectasis is recognized globally, pediatric data are limited, particularly on trends over the years. Also, no published data exists regarding whether vitamin D deficiency or insufficiency and human T-cell lymphotropic virus type 1 (HTLV-1) infection, both found to be related to severe bronchiectasis in First Nations adults, also are important in children with bronchiectasis.

RESEARCH QUESTION

Among children with bronchiectasis, (1) have the clinical and BAL profiles changed between two 5-year periods (period 1, 2007-2011; period 2, 2012-2016) and (b) are vitamin D deficiency or insufficiency, HTLV-1 infection, or both associated with radiologic severity of bronchiectasis?

STUDY DESIGN AND METHODS

We analyzed the data from children with bronchiectasis prospectively enrolled at Royal Darwin Hospital, Australia, at the first diagnosis; that is, no child was included in both periods. Data collected include demographics, BAL, bloods, and high-resolution CT scan of the chest evaluated using the Bhalla and modified Bhalla scores.

RESULTS

The median age of the 299 children was 2.2 years (interquartile range, 1.5-3.7 years). One hundred sixty-eight (56%) were male and most were First Nations (92%). Overall, bronchiectasis was high over time, particularly among First Nations children. In the later period, numbers of non-First Nations children more than tripled, but did not reach statistical significance. In period 2 compared with period 1, fewer First Nations children demonstrated chronic cough (period 1, 61%; period 2, 47%; P = .03), were younger, First Nations children were less likely to have received azithromycin (period 1, 42%; period 2, 21%; P < .001), and the BAL fluid of First Nations children showed lower Haemophilus influenzae and Moraxella catarrhalis infection. HTLV-1 infection was not detected, and vitamin D deficiency or insufficiency did not correlate with severity of bronchiectasis.

INTERPRETATION

Bronchiectasis remains high particularly among First Nations children. Important changes in their profiles that arguably reflect improvements were present, but overall, the profiles remained similar. Although vitamin D deficiency was uncommon, its role in children with bronchiectasis requires further evaluation. HTLV-1 infection was nonexistent and is unlikely to play any role in First Nations children with bronchiectasis.

Association Between Vitamin D and Novel SARS-CoV-2 Respiratory Dysfunction - A Scoping Review of Current Evidence and Its Implication for COVID-19 Pandemic

OBJECTIVES

To assess the association between vitamin D deficiency and increased morbidity/mortality with COVID-19 respiratory dysfunction.

DESIGN

Scoping review.

DATA SOURCES

Ovid MEDLINE (1946 to 24 of April 2020) and PubMed (2020 to 17 of September 2020).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

A search using the search terms: [(cholecalciferol or ergocalciferol or vitamin D2 or vitamin D3 or vitamin D or 25OHD) and (SARS-CoV-2 or coronavirus or COVID or betacoronavirus or MERS-CoV or SARS-CoV or respiratory infection or acute respiratory distress syndrome or ARDS)]m.p. was conducted on the 24/04/2020 (Search A) and 17/09/2020 (Search B).

RESULTS

91 studies were identified as being concerned with Acute Respiratory Infection (ARI)/Acute Respiratory Distress Syndrome (ARDS) and vitamin D, and 25 publications specifically explored the role of vitamin D deficiency in the development and progression of SARS-CoV-2/COVID-19 related ARDS. Search "A" identified three main themes of indirect evidence supporting such an association. Consistent epidemiological evidence exists linking low vitamin D levels to increased risk and severity of respiratory tract infections. We also report on plausible biological processes supporting such an association; and present weaker evidence supporting the benefit of vitamin D supplementation in reducing the risk and severity of ARIs. Uncertainty remains about what constitutes an appropriate dosing regimen in relation to reducing risk/severity of ARI/ARDS. More recent evidence (Search B) provided new insights into some direct links between vitamin D and COVID-19; with a number of cohort and ecological studies supporting an association with PCR-positivity for SARS-CoV-2 and vitamin D deficiency. The exact efficacy of the vitamin D supplementation for prevention of, or as an adjunct treatment for COVID-19 remains to be determined; but a number of randomized control trials (RCTs) currently underway are actively investigating these potential benefits.

CONCLUSION

Our rapid review of literature supports the need for observational studies with COVID-19 infected populations to measure and assess vitamin D levels in relation to risk/severity and outcomes; alongside RCTs designed to evaluate the efficacy of supplementation both in preventive and therapeutic contexts. The overlap in the vitamin D associated biological pathways with the dysregulation reported to drive COVID-19 outcomes warrants further investigation.

Vitamin D-binding protein as it is understood in 2016: is it a critical key with which to help to solve the calcitriol conundrum?

Background The misnamed 'vitamin' D is actually the hormone calcitriol (1,25 dihydroxyhydroxyvitamin D). It has a central regulatory role in calcium metabolism, and more widely in the immune system. The prohormone calcifediol (25 hydroxyvitamin D) is more easily measured in the laboratory and is the analyte used in reference interval formulation. Being highly lipid soluble, both calcifediol and calcitriol travel in the bloodstream on carriage proteins, principally on vitamin D-binding protein. Summary This review reports our current understanding of vitamin D-binding protein. Its genetic determinants and their effect on it and secondarily on calcifediol concentrations and assays are described. Its complex interplay with parathyroid hormone is considered. The analytical state of the art is translated into the challenge it imposes clinically, in the formulation of reference intervals and in their use in advising and managing patients. Several recent challenges thrown up to laboratories by percipient clinicians highlight the dilemma vitamin D-binding protein poses. A way forward is suggested.

Children with lower respiratory tract infections and serum 25-hydroxyvitamin D3 levels: A case-control study

BACKGROUND

Pneumonia is the leading cause of death in children under age of 5 years worldwide. The role of vitamin D in respiratory infections including pneumonia is unclear; therefore, we aimed to determine if children with lower respiratory tract infections had low serum 25-hydroxyvitamin D₃ .

METHODS

We performed a case-control study of children ages 3-60 months from the Guatemala City metropolitan area, hospitalized with community-acquired pneumonia between September and December 2012. Controls were selected from the well-baby/care immunization clinics serving the population from which cases emerged. We analyzed serum 25-hydroxyvitamin D₃ levels and conducted parental interviews to assess subject age, sex, race, feeding type, vitamin D supplementation, frequency of sun exposure, and maternal education. Height and weight were ascertained from medical records. Complete information was available for 70 (83%) of 84 eligible cases and 68 (60%) of 113 eligible controls.

RESULTS

The median (IQR) serum 25-hydroxyvitamin D₃ concentration for cases was 23.2 ng/ml (14.4-29.9) compared to 27.5 ng/ml (21.4-32.3) in controls (P = 0.006). Multiple regression analysis using an a priori cut-point for vitamin D of <20 ng/ml showed that children with lower respiratory tract infections were more likely to have low 25-hydroxyvitamin D₃ levels than controls (adjusted odds ratio 2.4, 95% confidence interval 1.1-5.2, P = 0.02).

CONCLUSIONS

Children with lower respiratory tract infections in Guatemala had low 25-hydroxyvitamin D₃ levels. Pediatr Pulmonol. 2016;51:1080-1087. © 2016 Wiley Periodicals, Inc.

Cord blood vitamin D and the risk of acute lower respiratory infection in Indigenous infants in the Northern Territory

OBJECTIVES

To assess vitamin D status in Indigenous mothers and infants in the Northern Territory, and to determine whether cord blood vitamin D levels are correlated with the risk of infant hospitalisation for acute lower respiratory infection (ALRI).

DESIGN AND PARTICIPANTS

Within a nested cohort of 109 Indigenous mother-infant pairs recruited between 2006 and 2011, we used liquid chromatography-mass spectrometry to measure vitamin D (25(OH)D3) levels in maternal blood during pregnancy (n = 33; median gestation, 32 weeks [range, 28-36 weeks]) and at birth (n = 106; median gestation, 39 weeks [range, 34-41 weeks]), in cord blood (n = 84; median gestation, 39 weeks [range, 36-41 weeks]), and in infant blood at age 7 months (n = 37; median age, 7.1 months [range, 6.6-8.1 months]).

MAIN OUTCOME MEASURE

ALRI hospitalisations during the first 12 months of infancy, identified using International Classification of Diseases coding (J09-J22, A37-A37.9).

RESULTS

Compared with mean 25(OH)D3 levels in maternal blood during pregnancy (104 nmol/L), mean levels were 23% lower in maternal blood at birth (80 nmol/L) and 48% lower in cord blood samples (54 nmol/L). The mean cord blood 25(OH)D3 concentration in seven infants subsequently hospitalised for an ALRI was 37 nmol/L (95% CI, 25-48 nmol/L), lower than the 56 nmol/L (95% CI, 51-61 nmol/L) in the 77 infants who were not hospitalised with an ALRI (P = 0.025).

CONCLUSIONS

Cord blood 25(OH)D3 concentrations were about half those in maternal blood during the third trimester of pregnancy (about 7 weeks earlier). Most cord blood levels (80%) were classified as vitamin D insufficient (< 75 nmol/L) by existing guidelines, and were lower among infants who were subsequently hospitalised with an ALRI.

Serum Vitamin D Levels in Children with Recurrent Respiratory Infections and Chronic Cough

OBJECTIVES

To evaluate serum vitamin D levels in cases of recurrent respiratory infections and chronic cough and to investigate the effect of vitamin D therapy on recurrence of the diseases.

METHODS

This prospective observational study was performed by comparing serum vitamin D levels in children with recurrent respiratory infections, chronic cough and healthy children. One-hundred-one children with chronic cough, ninety-eight children with recurrent respiratory infections and one-hundred-twenty-four healthy children were enrolled in the study. A structured questionnaire was completed to collect data on demography, diet, duration of breastfeeding, vitamin D supplementation and family history for allergic diseases. In patients with low serum vitamin D levels (<20 ng/ml), vitamin D therapy was administered in addition to conventional treatment for the diseases. Patients were followed up for 6 mo and their complaints were evaluated.

RESULTS

Mean serum 25(OH) vitamin D level in the recurrent respiratory infections group was 11.97 ± 4.04 ng/ml, chronic cough group was 13.76 ± 4.81 ng/ml and control group was 31.91 ± 18.79 ng/ml. Comparison of serum 25(OH) vitamin D levels between the study groups revealed a statistically significant difference (p < 0.05). 25(OH)D deficiency in children was associated with increased frequency of recurrent respiratory infections and chronic cough.

CONCLUSIONS

To conclude, administration of supplementary vitamin D may be useful in the treatment and preventation of recurrent respiratory infections and chronic cough.