Vitamin D supplementation in respiratory diseases: evidence from randomized controlled trials

[Bone metabolism in patients evaluated for lung transplantation]

Introduction

Introduction: the prevalence of osteoporosis among candidates for lung transplantation is high and its pathophysiology is multifactorial. Objectives: to evaluate differences in bone mineral density, risk of fractures and bone remodeling markers in patients with terminal lung disease, at the time they are evaluated for lung transplantation, comparing two types of pathologies. Material and methods: fifty-nine subjects, proposed to receive a lung transplant due to advanced lung disease, were included in this study. They were divided into two groups according to their respiratory pathology: chronic obstructive pulmonary disease (COPD) and diffuse interstitial pulmonary disease (ILD). Demographic data were collected and bone densitometry, blood analysis with markers of bone remodeling, spirometry, six-minute walk test (6MWT), echocardiography and cardiac catheterization were performed Results: no differences were found between the groups, regarding their age, sex, BMI or exposure to tobacco. A higher prevalence of osteoporosis and a higher FRAX were observed in the group with COPD. Regarding bone remodeling markers, higher parathyroid hormone (PTH) and higher osteocalcin were found in the COPD group. Vitamin D was lower in COPD patients. Conclusions: two out of three of the patients evaluated for lung transplantation had osteopenia or osteoporosis. The prevalence of osteoporosis and FRAX is higher in COPD patients. Vitamin D supplementation should be considered in certain patients. Differences in bone remodeling markers may be useful for suspected osteoporosis and therapeutic management.

Increased Risk of Vitamin D Deficiency Among HIV-Infected Individuals: A Systematic Review and Meta-Analysis

Background: Human immunodeficiency virus (HIV) infection is a heavy burden worldwide. Observational studies have reported a high prevalence of vitamin D deficiency (VDD) among people living with HIV (PLWH). However, its deficiency is also a global health problem. Therefore, we conducted a meta-analysis and systemic review to compare differences between HIV-infected subjects and non-HIV-infected subjects.

Methods: We searched PubMed, Web of Science, Embase, and Cochrane library. We extracted data, including demographic information, study type, vitamin D-related values, and HIV-related values, ultimately including 15 studies after removing duplicates and screening titles, abstracts, and full texts and finally performing a meta-analysis in terms of vitamin D level and vitamin D deficiency prevalence.

Results: Regarding VDD prevalence, the HIV vs. the non-HIV group had an odds ratio of 1.502 (95% CI, 1.023–2.205; P = 0.038). In the subgroup analysis, the odds ratios were 1.647 (95% CI, 1.020–2.659; P = 0.041; I² = 94.568) from 7 studies (age over 40), 2.120 (95% CI, 1.122–4.008; P = 0.021; I² = 0.000) from 2 studies (BMI less than or equal to 25), 1.805 (95% CI, 1.373–2.372; P = 0.042; I² = 74.576) from 7 studies (latitude <40), 2.120 (95% CI, 1.122–4.088; P = 0.021; I² = 0.000) from 2 studies (only included male participants), and 2.296 (95% CI, 1.287–4.097; P = 0.005; I² = 19.927) from 3 studies (only included ART-experienced participants). Thirteen studies were deemed to have moderate quality, while two had high quality.

Conclusions: HIV infected subjects are prone to have VDD compared with general population. ART, older age, lower BMI, lower latitude and male sex may present risk factors for VDD in PLWH.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=228096.

Review of the Effectiveness of Various Adjuvant Therapies in Treating Mycobacterium tuberculosis

Tuberculosis disease is caused by the bacterium Mycobacterium tuberculosis. It is estimated that 10 million people have developed tuberculosis disease globally, leading to 1.4 million deaths in 2019. Treatment of tuberculosis has been especially challenging due to the rise of multidrug-resistant (MDR-TB) and extensive drug-resistant (XDR-TB) tuberculosis. In addition to drug-resistant genotypes, the standard treatment of tuberculosis by first-line agents is also challenging due to toxicity and costs. In the last four decades, there have only been two new anti-tuberculosis agents—bedaquiline and delamanid. Therefore, shorter, safer, and more cost-effective therapies are needed to adequately treat tuberculosis. In this review, we explore various adjuvants such as glutathione, everolimus, vitamin D, steroid, aspirin, statin, and metformin and their usefulness in reducing the burden of tuberculosis. Glutathione, everolimus, aspirin, and metformin showed the most promise in alleviating the burden of tuberculosis. Despite their potential, more clinical trials are needed to unequivocally establish the effectiveness of these adjuvants as future clinical therapies. Methods: The journals for this review were selected by conducting a search via PubMed, Google Scholar, and The Lancet. Our first search included keywords such as “tuberculosis” and “adjuvant therapy.” From the search, we made a list of adjuvants associated with tuberculosis, and this helped guide us with our second online database search. Using the same three online databases, we searched “tuberculosis” and “respective therapy.” The adjuvants included in the paper were selected based on the availability of sufficient research and support between the therapy and tuberculosis. Adjuvants with minimal research support were excluded. There were no specific search criteria regarding the timing of publication, with our citations ranging between 1979 to 2021.

Relevance of vitamin D3 in COVID-19 infection

SARS-CoV-2 virus, the main culprit for COVID-19 disaster, has triggered a gust of curiosity both in the mechanism of action of this infection as well as potential risk factors for disease generation and regimentation. The prime focus of the present review, which is basically a narrative one, is in utilizing the current concepts of vitamin D₃ as an agent with myriad functions, one of them being immunocompetence and a promising weapon for both innate and adaptive immunity against COVID-19 infection. Some of the manifestations of SARS-CoV-2 virus such as Acute Respiratory Distress Syndrome (ARDS) overlap with the pathophysiological effects that are overcome due to already established role of vitamin D₃ e.g., amelioration of cytokine outburst. Additionally, the cardiovascular complications due to COVID-19 infection may also be connected to vitamin D₃ levels and the activity of its active forms. Eventually, we summarise the clinical, observational and epidemiological data of the respiratory diseases including COVID-19 disease and try to bring its association with the potential role of vitamin D₃, in particular, the activity of its active forms, circulating levels and its supplementation, against dissemination of this disease.

A Spatio-Temporal Analysis of the Environmental Correlates of COVID-19 Incidence in Spain

The novel SARS-CoV2 has disrupted health systems and the economy, and public health interventions to slow its spread have been costly. How and when to ease restrictions to movement hinges in part on whether SARS-CoV2 will display seasonality due to variations in temperature, humidity, and hours of sunshine. Here, we address this question by means of a spatio-temporal analysis in Spain of the incidence of COVID-19, the disease caused by the virus. Use of spatial Seemingly Unrelated Regressions (SUR) allows us to model the incidence of reported cases of the disease per 100,000 population as an interregional contagion process, in addition to a function of temperature, humidity, and sunshine. In the analysis we also control for GDP per capita, percentage of older adults in the population, population density, and presence of mass transit systems. The results support the hypothesis that incidence of the disease is lower at higher temperatures and higher levels of humidity. Sunshine, in contrast, displays a positive association with incidence of the disease. Our control variables also yield interesting insights. Higher incidence is associated with higher GDP per capita and presence of mass transit systems in the province; in contrast, population density and percentage of older adults display negative associations with incidence of COVID-19.

A Spatio-Temporal Analysis of the Environmental Correlates of COVID-19 Incidence in Spain

The novel SARS-CoV2 has disrupted health systems and the economy, and public health interventions to slow its spread have been costly. How and when to ease restrictions to movement hinges in part on whether SARS-CoV2 will display seasonality due to variations in temperature, humidity, and hours of sunshine. Here, we address this question by means of a spatio-temporal analysis in Spain of the incidence of COVID-19, the disease caused by the virus. Use of spatial Seemingly Unrelated Regressions (SUR) allows us to model the incidence of reported cases of the disease per 100,000 population as an interregional contagion process, in addition to a function of temperature, humidity, and sunshine. In the analysis we also control for GDP per capita, percentage of older adults in the population, population density, and presence of mass transit systems. The results support the hypothesis that incidence of the disease is lower at higher temperatures and higher levels of humidity. Sunshine, in contrast, displays a positive association with incidence of the disease. Our control variables also yield interesting insights. Higher incidence is associated with higher GDP per capita and presence of mass transit systems in the province; in contrast, population density and percentage of older adults display negative associations with incidence of COVID-19.

In sickness and in health: pivotal role of vitamin D

Within the last several years, frequency of vitamin D testing has multiplied substantially all over the world, since it has been shown to have an important role in many diseases and conditions. Even though liquid chromatography - tandem mass spectrometry (LC-MS/MS) has been identified as "gold standard" method for vitamin D measurement, most laboratories still use immunochemistry methods. Besides analytical problems (hydrophobicity, low circulating concentrations, ability to bind to lipids, albumins and vitamin D binding protein, presence of multiple vitamin D metabolites and variable ratios of 25(OH)D₂ and 25(OH)D₃ in the blood), vitamin D shows great preanalytical variability, since its concentration is drastically influenced by seasonal changes, exposure to sun, type of clothes or sun block creams. Vitamin D is mostly measured in serum or plasma, but new studies are showing importance of measuring vitamin D in pleural effusions, breast milk, urine, synovial fluid and saliva. Besides the main role in calcium homeostasis and bone metabolism, many studies linked vitamin D deficiency with cancer, cardiovascular diseases, diabetes, fertility and many other conditions. However, even though initial observational studies indicated that supplementation with vitamin D might be beneficial in disease development and progression; first results of well-designed randomized controlled prospective studies did not find differences in frequency of cardiovascular events or invasive cancer between patients taking vitamin D supplementation compared to placebo. In the light of these recent findings, validity of excessive vitamin D testing remains an open question.

MECHANISMS IN ENDOCRINOLOGY: Vitamin D and COVID-19

The SARS-CoV-2 virus responsible for the COVID-19 pandemic has generated an explosion of interest both in the mechanisms of infection leading to dissemination and expression of this disease, and in potential risk factors that may have a mechanistic basis for disease propagation or control. Vitamin D has emerged as a factor that may be involved in these two areas. The focus of this article is to apply our current understanding of vitamin D as a facilitator of immunocompetence both with regard to innate and adaptive immunity and to consider how this may relate to COVID-19 disease. There are also intriguing potential links to vitamin D as a factor in the cytokine storm that portends some of the most serious consequences of SARS-CoV-2 infection, such as the acute respiratory distress syndrome. Moreover, cardiac and coagulopathic features of COVID-19 disease deserve attention as they may also be related to vitamin D. Finally, we review the current clinical data associating vitamin D with SARS-CoV-2 infection, a putative clinical link that at this time must still be considered hypothetical.

Does Serum Vitamin D Level Affect COVID-19 Infection and Its Severity?-A Case-Control Study

BACKGROUND

As effective medication to treat COVID-19 is currently unavailable, preventive remedies may be particularly important.

OBJECTIVE

To examine the relationship between serum 25-hydroxy vitamin D (25(OH)D) level and COVID-19 infection, its severity, and its clinical case characteristics.

METHODS

This case-control study compared serum 25(OH)D levels and rates of vitamin D deficiency (VDD) between 80 healthy controls and 62 patients diagnosed with COVID-19 and admitted to Guangxi People's Hospital, China, 2/16/2020-3/16/2020. Cases were categorized into asymptomatic, mild/moderate, and severe/critical disease. Logistic regression analysis was conducted to examine the associations between 25(OH)D level, or VDD, and case status/severity of COVID-19 while controlling for demographics and comorbidities. A threshold level of vitamin D for conveying COVID-19 risk was estimated.

RESULTS

Severe/critical COVID-19 cases were significantly older and had higher percentages of comorbidity (renal failure) compared to mild cases. The serum 25(OH)D concentration in COVID-19 patient was much lower than that in healthy control. And 25(OH)D level was the lowest in severe/critical cases, compared with mild cases. In further, significantly higher rates of VDD were found in COVID-19 cases (41.9%) compared to healthy controls (11.1%). And VDD was the greatest in severe/critical cases (80%), compared with mild cases (36%). These statistically significant associations remained even after controlling for demographics and comorbidities. A potential threshold of 25(OH)D (41.19 nmol/L) to protect against COVID-19 was identified.

CONCLUSION

Elderly and people with comorbidities were susceptible to severe COVID-19 infection. VDD was a risk factor for COVID-19, especially for severe/critical cases. While further confirmation is needed, vitamin D supplementation may have prevention or treatment potential for COVID-19 disease.

Effectiveness of vitamin D supplementation on the outcome of pulmonary tuberculosis treatment in adults: a meta-analysis of randomized controlled trials

Supplemental Digital Content is available in the text

Background:

Tuberculosis (TB) is one of the most debilitating diseases worldwide. Current studies have shown that vitamin D plays a significant role in host immune defense against Mycobacterium tuberculosis, but clinical trials reported inconsistent results. Therefore, we systematically reviewed the literature to investigate whether vitamin D supplementation could improve the effect of anti-TB therapy.

Methods:

We systematically searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from their inception to February 8th, 2019 for randomized controlled trials on vitamin D supplementation in patients with pulmonary TB receiving anti-TB therapy. The primary outcomes were time to sputum culture and smear conversion and proportion of participants with negative sputum culture. The secondary outcomes were clinical response to treatment and adverse events. A random-effects model was used to pool studies. Data were analyzed using RevMan 5.3 software.

Results:

Five studies with a total of 1126 participants were included in our meta-analysis. Vitamin D supplementation did not shorten the time to sputum culture and smear conversion (hazard ratio [HR] 1.04, 95% confidence interval [CI] 0.89–1.23, P = 0.60; HR 1.15, 95% CI 0.93–1.41, P = 0.20, respectively) and did not lead to an increase in the proportion of participants with negative sputum culture (relative risk [RR] 1.04, 95% CI 0.97–1.11, P = 0.32). However, it reduced the time to sputum culture conversion in the sub-group of participants with TaqI tt genotype (HR 8.09, 95% CI 1.39–47.09, P = 0.02) and improved the multidrug-resistant (MDR) TB sputum culture conversion rate (RR 2.40, 95% CI 1.11–5.18, P = 0.03). There was no influence on secondary outcomes.

Conclusions:

Vitamin D supplementation had no beneficial effect on anti-TB treatment, but it reduced the time to sputum culture conversion in participants with tt genotype of the TaqI vitamin D receptor gene polymorphism and improved the MDR TB sputum culture conversion rate.

COPD as an independent risk factor for osteoporosis and fractures

Fractures are common in individuals with COPD and occur at higher bone mass values than expected. COPD appears to be an important risk factor for bone fragility.

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) have an increased risk of osteoporosis and fractures, but screening and prophylactic measures to prevent both disorders are often neglected in this population. This case-control study assessed the prevalence of osteopenia, osteoporosis, and fractures in patients with COPD, and identified potential risk factors for fractures in this population.

METHODS

Overall, 91 patients with COPD (COPD group; COPDG) and 81 age- and sex-matched controls (control group; CG) were assessed with bone mineral density (BMD), thoracic/lumbar spine radiographs, and serum PTH and 25-hydroxyvitamin D (25[OH]D) levels. The occurrence of prior fractures was retrieved from clinical history.

RESULTS

The prevalence of total fractures in the COPDG was 57.1% (odds of fracture 4.7 times greater compared with the CG), and the femoral neck T-score emerged as the best predictor of fractures. Compared with the CG, the COPDG had lower spine and femoral BMD (p ≤ 0.01) and 25(OH)D levels (p = 0.01) and 2.6 times greater odds of osteoporosis. Among men, vertebral fractures were more prevalent in the COPDG versus CG (25.9% vs. 6.5%, respectively, p = 0.01). The odds of fracture increased with femoral neck T-scores ≤ - 2.7 in the CG and ≤ - 0.6 in the COPDG.

CONCLUSION

These results add robust evidence to an increased odds of osteoporosis and fractures in COPD. Fractures in the COPDG occurred at higher BMD values than expected, suggesting that COPD may be an independent marker of fracture risk, reinforcing a need for regular osteoporosis screening with BMD measurement and prophylaxis of fractures in patients with this disorder.

Determinants of Vitamin D Supplementation among Individuals with Type 1 Diabetes

Half of the individuals with type 1 diabetes (T1DM) may present Vitamin D (VD) deficiency. There is little known about factors determining a decision on VD supplementation. The study aimed to determine the factors affecting vitamin D supplementation in people with T1DM. A cross-sectional survey study using the authors’ questionnaire paper and its digital version was performed. The questions involved data on the basic characteristics of the respondent, medical history, VD supplementation status, influence of the social environment, self-education, and the most important personal motivator for VD supplement use. Multivariate logistic regression analysis was performed. We collected a total of n = 184 papers and n = 550 digital complete surveys. From 734 total respondents, 62.0% declared VD supplementation. The main personal rationale for VD supplementation were recommendation of medical specialist 172 (37.8%) and self-education 135 (29.7%). The main reasons for non-supplementation of VD were lack of knowledge about VD 159 (57.0%) and lack of motivation 77 (27.6%). VD supplementation was independently associated with a family doctor (odds ratio (OR), 95% confidence interval (CI): 4.67, 2.32–9.40) or medical specialist recommendation (16.20, 9.57–27.43), and self-education (5.97, 3.90–9.13). Most Polish individuals with T1DM use VD supplements, and the decision is related to physicians’ recommendations and self-education.

Effect of Vitamin D Supplementation in the Prevention of Recurrent Pneumonia in Under-Five Children

OBJECTIVE

To assess the effect of vitamin D supplementation in the prevention of recurrent pneumonia in under-five children.

METHODS

The present one year 8 months longitudinal, community-based randomized controlled study included a total of 100 under-five children with pneumonia. Children were divided into two groups: intervention group (Group I: standard treatment with vitamin D 300,000 IU; n = 50) and control group (Group C: standard treatment only; n = 50). As nine samples were hemolyzed, groups I and C comprised of 46 and 45 children, respectively. The children were followed up for 1 y and signs of upper respiratory tract infections (URTI), lower respiratory tract infections (LRTI), vitamin D deficiency, and vitamin D toxicity were recorded.

RESULTS

The male to female ratio in group C and I was 1.27:1 and 1.5:1, respectively (P = 0.420). Age, gender, birth, anthropometric and clinical characteristics, and feeding habits were not statistically significant (P > 0.05) between both the cohorts (Group C and I). Children with reduced vitamin D levels were high in group C (25) when compared to the group I (15). During all the follow-ups, the URTI and LRTI episodes, severity of pneumonia, number of hospital admissions, complications, mean episodes of LRTI, and mean duration of LRTI were comparable between group I and group C (P > 0.05).

CONCLUSIONS

Overall, the present study highlights that oral vitamin D (300,000 IU bolus dose quarterly) has some beneficial effect in the prevention of recurrent pneumonia in under-five children, although, not to a significant degree. Hence, it is recommended that further studies are required to demonstrate a significant effect of vitamin D in the prevention of pneumonia.

Skeletal and Extraskeletal Actions of Vitamin D: Current Evidence and Outstanding Questions

The etiology of endemic rickets was discovered a century ago. Vitamin D is the precursor of 25-hydroxyvitamin D and other metabolites, including 1,25(OH)2D, the ligand for the vitamin D receptor (VDR). The effects of the vitamin D endocrine system on bone and its growth plate are primarily indirect and mediated by its effect on intestinal calcium transport and serum calcium and phosphate homeostasis. Rickets and osteomalacia can be prevented by daily supplements of 400 IU of vitamin D. Vitamin D deficiency (serum 25-hydroxyvitamin D <50 nmol/L) accelerates bone turnover, bone loss, and osteoporotic fractures. These risks can be reduced by 800 IU of vitamin D together with an appropriate calcium intake, given to institutionalized or vitamin D-deficient elderly subjects. VDR and vitamin D metabolic enzymes are widely expressed. Numerous genetic, molecular, cellular, and animal studies strongly suggest that vitamin D signaling has many extraskeletal effects. These include regulation of cell proliferation, immune and muscle function, skin differentiation, and reproduction, as well as vascular and metabolic properties. From observational studies in human subjects, poor vitamin D status is associated with nearly all diseases predicted by these extraskeletal actions. Results of randomized controlled trials and Mendelian randomization studies are supportive of vitamin D supplementation in reducing the incidence of some diseases, but, globally, conclusions are mixed. These findings point to a need for continued ongoing and future basic and clinical studies to better define whether vitamin D status can be optimized to improve many aspects of human health. Vitamin D deficiency enhances the risk of osteoporotic fractures and is associated with many diseases. We review what is established and what is plausible regarding the health effects of vitamin D.

Vitamin D as an Adjunctive Treatment to Standard Drugs in Pulmonary Tuberculosis Patients: An Evidence-Based Case Report

Background

Vitamin D has a prominent role in the body's innate immunity as it is important in the maintenance of macrophages and monocytes and its function in defending against infections. In-vitro studies have established vitamin D's potential role in tuberculosis (TB) infection, in that it restricts Mycobacterium tuberculosis growth, thus implying the potential benefit of vitamin D as an adjunctive treatment for TB. However, clinical trials and reviews have contradicting findings regarding the true clinical efficacy of adjunctive vitamin D, particularly in reducing the sputum conversion rate (SCR).

Objective

This study aims to update the current evidence regarding vitamin D supplementation as an adjunctive treatment in achieving the smear sputum conversion rate (SCR) among pulmonary TB patients.

Method

A comprehensive search was conducted in October 2018 in PubMed-NCBI, MEDLINE-OVID, SCOPUS-Elsevier, and Cochrane. The selection of studies was done as per the predetermined inclusion and exclusion criteria of this EBCR and resulted in the inclusion of 11 eligible studies (8 RCTs and 3 systematic reviews). The selected studies were then critically appraised for their validity, importance, and applicability according to the CEBM (Centre for Evidence-Based Medicine) appraisal tools.

Results

Overall, most of the trials showed no statistically significant changes in terms of the proportion of TB patients with a negative sputum smear conversion in the group treated with an adjunctive therapy vs. the group treated with standard antituberculosis therapy alone. Only one trial showed significant results, which was conducted in a population of TB patients with vitamin D deficiency. Furthermore, overall the reviews showed no significant change in the 8-week sputum smear conversion after treatment within the group given vitamin D in comparison to those who were not.

Conclusion

Vitamin D as adjunctive therapy in TB patients shows no clinical improvement in terms of sputum conversion to antituberculosis management.

Vitamin D Binding Protein: A Historic Overview

Vitamin D and all its metabolites are bound to a specific vitamin D binding protein, DBP. This protein was originally first discovered by its worldwide polymorphism and called Group-specific Component (GC). We now know that DBP and GC are the same protein and appeared early in the evolution of vertebrates. DBP is genetically the oldest member of the albuminoid family (including albumin, α-fetoprotein and afamin, all involved in transport of fatty acids or hormones). DBP has a single binding site for all vitamin D metabolites and has a high affinity for 25OHD and 1,25(OH)2D, thereby creating a large pool of circulating 25OHD, which prevents rapid vitamin D deficiency. DBP of higher vertebrates (not amphibians or reptiles) binds with very high affinity actin, thereby preventing the formation of polymeric actin fibrils in the circulation after tissue damage. Megalin is a cargo receptor and is together with cubilin needed to reabsorb DBP or the DBP-25OHD complex, thereby preventing the urinary loss of these proteins and 25OHD. The total concentrations of 25OHD and 1,25(OH)2D in DBP null mice or humans are extremely low but calcium and bone homeostasis remain normal. This is the strongest argument for claiming that the "free hormone hypothesis" also applies to the vitamin D hormone, 1,25(OH)2D. DBP also transports fatty acids, and can play a role in the immune system. DBP is genetically very polymorphic with three frequent alleles (DBP/GC 1f, 1s, and 2) but in total more than 120 different variants but its health consequences, if any, are not understood. A standardization of DBP assays is essential to further explore the role of DBP in physiology and diseases.