Nutritional therapy of older osteoporotic people with supplemental calcium and vitamin D: side effects, fracture rates, and survival - an internationalised meta-analysis.

BACKGROUND AND OBJECTIVES: Recent controversy over the bone benefits of calcium and vitamin D supplementation, and the potential detrimental effects of excess calcium supplementation, has confused clinicians. To systematically evaluate the effectiveness and safety of vitamin D combined with calcium in preventing and treating osteoporotic symptoms in the elderly. METHODS AND STUDY DESIGN: Databases were searched to collect randomized controlled trials (RCTs) on vitamin D combined with calcium in the prevention and treatment of osteoporotic fractures in the elderly. After screening the literature, extracting data, and assessing the risk of bias in the included studies, the Meta-analysis was performed. RESULTS: 19 RCTs were included, including 69,234 patients. Meta-analysis results showed that the mortality rate of the vitamin D combined with calcium group was not statistically significant compared with the control group; the calcium combined with vitamin D significantly reduced the incidence of fractures compared with the control group，Density and serum 25-hydroxyl concentration, adverse reactions of calcium combined with vitamin D were higher than those in the control group. CONCLUSIONS: The combination of vitamin D and calcium has no difference in mortality rate, and it can prevent fractures in the elderly, and enhance bone density and serum 25-hydroxyvitamin D concentration, but still need to pay attention to adverse reactions in the gastrointestinal tract.

Efficacy and safety of vitamin D supplementation on psoriasis: A systematic review and meta-analysis.

OBJECTIVES: Our aim was to analyze the results of published randomized controlled trials (RCTs) on vitamin D supplementation for psoriasis in order to explore its effectiveness and safety. PATIENTS AND METHODS: As of July 7 2023, we conducted a systematic literature search in PubMed, Cochrane, Embase, and Web of Science Core Collection databases. The study outcomes included change values in Psoriasis Area and Severity Index (PASI) (at 3 months, 6 months, and end of follow-up)/Dermatology Life Quality Index (DLQI)/Psoriasis disability index (PDI)/C-reactive protein (CRP), and adverse events. RESULTS: 333 patients from 4 studies were evaluated. Pooled analyses showed no significant effect of DLQI/PDI/CRP change value (P > 0.05) or PASI change value (3 months, end of follow-up; P > 0.05). Sensitivity analyses and statistical tests did not support the results of the PASI change values (6 months, P = 0.05). However, the results of subgroup analyses should not be ignored(supplementation with vitamin D2 or Asia would be more effective; P = 0.03). There were no serious adverse effects, and only a few individuals experienced nausea. CONCLUSIONS: The efficacy and safety of vitamin D supplementation in the treatment of psoriasis remains unremarkable. The search for a new prognostic index that combines clinical and laboratory factors is needed to compensate for the shortcomings of existing measures and provide stronger evidence of validity.

Vitamin D for the treatment of inflammatory bowel disease.

BACKGROUND: Vitamin D possesses immunomodulatory properties and has been implicated in the pathogenesis and severity of inflammatory bowel disease (IBD). Animal studies and emerging epidemiological evidence have demonstrated an association between vitamin D deficiency and worse disease activity. However, the role of vitamin D for the treatment of IBD is unclear. OBJECTIVES: To evaluate the benefits and harms of vitamin D supplementation as a treatment for IBD. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was Jun 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in people of all ages with active or inactive IBD comparing any dose of vitamin D with another dose of vitamin D, another intervention, placebo, or no intervention. We defined doses as: vitamin D (all doses), any-treatment-dose vitamin D (greater than 400 IU/day), high-treatment-dose vitamin D (greater than 1000 IU/day), low-treatment-dose vitamin D (400 IU/day to 1000 IU/day), and supplemental-dose vitamin D (less than 400 IU/day). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. clinical response for people with active disease, 2. clinical relapse for people in remission, 3. quality of life, and 4. withdrawals due to adverse events. Our secondary outcomes were 5. disease activity at end of study, 6. normalisation of vitamin D levels at end of study, and 7. total serious adverse events. We used GRADE to assess certainty of evidence for each outcome. MAIN RESULTS: We included 22 RCTs with 1874 participants. Study duration ranged from four to 52 weeks. Ten studies enroled people with Crohn's disease (CD), five enroled people with ulcerative colitis (UC), and seven enroled people with CD and people with UC. Seventeen studies included adults, three included children, and two included both. Four studies enroled people with active disease, six enroled people in remission, and 12 enroled both. We assessed each study for risk of bias across seven individual domains. Five studies were at low risk of bias across all seven domains. Ten studies were at unclear risk of bias in at least one domain but with no areas of high risk of bias. Seven studies were at high risk of bias for blinding of participants and assessors. Vitamin D (all doses) versus placebo or no treatment Thirteen studies compared vitamin D against placebo or no treatment. We could not draw any conclusions on clinical response for UC as the certainty of the evidence was very low (risk ratio (RR) 4.00, 95% confidence interval (CI) 1.51 to 10.57; 1 study, 60 participants). There were no data on CD. There may be fewer clinical relapses for IBD when using vitamin D compared to placebo or no treatment (RR 0.57, 95% CI 0.34 to 0.96; 3 studies, 310 participants). The certainty of the evidence was low. We could not draw any conclusions on quality of life for IBD (standardised mean difference (SMD) -0.13, 95% CI -3.10 to 2.83 (the SMD value indicates a negligent decrease in quality of life, and the corresponding CIs indicate that the effect can range from a large decrease to a large increase in quality of life); 2 studies, 243 participants) or withdrawals due to adverse events for IBD (RR 1.97, 95% CI 0.18 to 21.27; 12 studies, 1251 participants; note 11 studies reported withdrawals but recorded 0 events in both groups. Thus, the RR and CIs were calculated from 1 study rather than 12). The certainty of the evidence was very low. High-treatment-dose vitamin D versus low-treatment-dose vitamin D Five studies compared high treatment vitamin D doses against low treatment vitamin D doses. There were no data on clinical response. There may be no difference in clinical relapse for CD (RR 0.48, 95% CI 0.23 to 1.01; 1 study, 34 participants). The certainty of the evidence was low. We could not draw any conclusions on withdrawals due to adverse events for IBD as the certainty of the evidence was very low (RR 0.89, 95% CI 0.06 to 13.08; 3 studies, 104 participants; note 2 studies reported withdrawals but recorded 0 events in both groups. Thus, the RR and CIs were calculated from 1 study rather than 3). The data on quality of life and disease activity could not be meta-analysed, were of very low certainty, and no conclusions could be drawn. Any-treatment-dose vitamin D versus supplemental-dose vitamin D Four studies compared treatment doses of vitamin D against supplemental doses. There were no data on clinical response and relapse. There were no data on quality of life that could be meta-analysed. We could not draw any conclusions on withdrawals due to adverse events for IBD as the certainty of the evidence was very low (RR 3.09, 95% CI 0.13 to 73.17; 4 studies, 233 participants; note 3 studies reported withdrawals but recorded 0 events in both groups. Thus, the RR and CIs were calculated from 1 study rather than 4). AUTHORS' CONCLUSIONS: There may be fewer clinical relapses when comparing vitamin D with placebo, but we cannot draw any conclusions on differences in clinical response, quality of life, or withdrawals, due to very low-certainty evidence. When comparing high and low doses of vitamin D, there were no data for clinical response, but there may be no difference in relapse for CD. We cannot draw conclusions on the other outcomes due to very low certainty evidence. Finally, comparing vitamin D (all doses) to supplemental-dose vitamin D, there were no data on clinical relapse or response, and we could not draw conclusions on other outcomes due to very low certainty evidence or missing data. It is difficult to make any clear recommendations for future research on the basis of the findings of this review. Future studies must be clear on the baseline populations, the purpose of vitamin D treatment, and, therefore, study an appropriate dosing strategy. Stakeholders in the field may wish to reach consensus on such issues prior to new studies.

Effects of vitamin D supplementation on ovulation and pregnancy in women with polycystic ovary syndrome: a systematic review and meta-analysis.

Objective: To evaluate the effect of vitamin D supplementation on pregnancy and ovulation in patients with polycystic ovary syndrome. Method: We searched Pubmed, Medline (via Ovid, 1974 to 2020), EMBASE (via Ovid, 1974 to 2020), Cochrane Central Register of Controlled Trials (via Ovid), Web of Science, CNKI, WangFang and the Vip database from inception until April 2021. Two researchers independently screened articles, collected data and evaluated the quality, with Review manager 5.3 for meta-analysis. Results: Totally 20 randomized controlled studies with 1961 subjects were included. Meta analysis showed that pregnancy rate [RR=1.44 (1.28, 1.62), p<0.00,001], ovulation rate [RR=1.42 (1.14, 1.78), p=0.002] and matured oocytes rate [RR=1.08 (1.03, 1.13), p=0.002] of vitamin D supplementation group were significantly higher than those of control group. Meanwhile, early miscarriage rate [RR=0.44 (0.30, 0.66), p<0.00,001], androgen level [MD=-2.31 (-3.51, -1.11), p=0.0002], luteinizing hormone [MD=-1.47 (-2.57, -0.36), p=0.009], follicle stimulating hormone [MD=-0.15 (-0.24, -0.05), p=0.002], and premature delivery rate [RR=0.38, 95% CI (0.21, 0.70), p=0.002] were declined significantly than the controls. However, only one article suggested that the progesterone [MD=6.52 (4.52, 8.52), p<0.05] in the vitamin D intervention group was increased. There was no notable difference in the biochemical pregnancy rate [RR=0.95 (0.55, 1.63), p=0.84], gestational hypertension rate [RR=0.40, 95% CI (0.15, 1.11), p=0.08], gestational diabetes mellitus rate [RR=0.27, 95% CI (0.05, 1.39), p=0.11], fertilization rate [RR=1.05 (1.00, 1.10), p=0.04], cleavage rate [RR=1.03 (0.99, 1.06), p=0.17], high-quality embryo rate [RR=1.08 (0.98, 1.20), p=0.10], endometrial thickness [MD=0.10], 77 (-0.23, 1.77), p=0.13], estrogen level [MD=-0.34 (-1.55, 0.87), p=0.59], LH/FSH [MD=-0.14, 95% CI (-0.48, 0.20), p=1.00] and anti-Mullerian hormone [MD=-0.22 (-0.65, 0.21), p=0.32]. Conclusion: Vitamin D supplementation contribute to the higher pregnancy and ovulation rates, and lower androgen, LH, FSH and early miscarriage rates in women with PCOS, regardless of the use of ovulation induction drugs or assisted reproductive technologies. However, no significant improvement was observed in fertilization rate or cleavage rate. Due to the limitation in quality of involved studies, more high-quality RCTs are needed for further validation. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier CRD42021250284.

Vitamin D regulates microflora and ameliorates LPS-induced placental inflammation in rats.

Preeclampsia is a pregnancy-specific disease, which has become an essential cause of perinatal and neonatal death. Gut microflora becomes the regulator of host immunity through the metabolic pathway. Epidemiological studies provide convincing evidence that vitamin D supplementation can prevent the onset of preeclampsia. However, research on the microbial mechanisms and effective treatment strategies for placental inflammation induced by lipopolysaccharide is lacking. In this study, pregnant rats were induced by LPS to establish a rat model of preeclampsia. Sixteen-sequence analysis was used to determine the composition of microflora in feces. In addition, the protective effect of vitamin D supplementation on LPS-preeclampsia rats was evaluated. The results showed that the blood pressure and creatinine of pregnant rats in the LPS group were significantly higher than those in the control group. In addition, LPS disturbed the intestinal microbial community and reduced microbial diversity. Vitamin D supplementation improves the symptoms of preeclampsia, increases the abundance of intestinal beneficial flora, normalizes the level of inflammatory factors LPS-induced by inhibiting the TLR4/MYD88/NF-κB pathway, and effectively resists the disturbance of uterine spiral artery remodeling induced by LPS. This study established that vitamin D-mediated microbial mechanisms and their inhibition are potential therapeutic targets for the treatment of preeclampsia.

Therapeutic and prophylactic role of vitamin D and curcumin in acetic acid-induced acute ulcerative colitis model.

Ulcerative Colitis (UC) is a disease that negatively affects quality of life and is associated with sustained oxidative stress, inflammation and intestinal permeability. Vitamin D and Curcumin; It has pharmacological properties beneficial to health, including antioxidant and anti-inflammatory properties. Our study investigates the role of Vitamin D and Curcumin in acetic acid-induced acute colitis model. To investigate the effect of Vitamin D and Curcumin, Wistar-albino rats were given 0.4 mcg/kg Vitamin D (Post-Vit D, Pre-Vit D) and 200 mg/kg Curcumin (Post-Cur, Pre-Cur) for 7 days and acetic acid was injected into all rats except the control group. Our results; colon tissue TNF-α, IL-1ß, IL-6, IFN-γ and MPO levels were found significantly higher and Occludin levels were found significantly lower in the colitis group compared to the control group (p < 0.05). TNF-α and IFN-γ levels decreased and Occludin levels increased in colon tissue of Post-Vit D group compared to colitis group (p < 0.05). IL-1ß, IL-6 and IFN-γ levels were decreased in colon tissue of Post-Cur and Pre-Cur groups (p < 0.05). MPO levels in colon tissue decreased in all treatment groups (p < 0.05). Vitamin D and Curcumin treatment significantly reduced inflammation and restored the normal histoarchitecture of the colon. From the present study findings, we can conclude that Vitamin D and Curcumin protect the colon from acetic acid toxicity with their antioxidant and anti-inflammatory potential.Brief synopsis: In this study; distal colon, distal ileum, jejunum and serum physiopathology in colitis induced by acetic acid and intestinal permeability were investigated. The roles of vitamin D and curcumin in this process were evaluated.

Vitamin D for the management of asthma.

BACKGROUND: Since the previous Cochrane Review on this topic in 2016, debate has continued surrounding a potential role for vitamin D in reducing risk of asthma exacerbation and improving asthma control. We therefore conducted an updated meta-analysis to include data from new trials completed since this date. OBJECTIVES: To evaluate the effectiveness and safety of administration of vitamin D or its hydroxylated metabolites in reducing the risk of severe asthma exacerbations (defined as those requiring treatment with systemic corticosteroids) and improving asthma symptom control. SEARCH METHODS: We searched the Cochrane Airways Group Trial Register and reference lists of articles. We contacted the authors of studies in order to identify additional trials. Date of last search: 8 September 2022. SELECTION CRITERIA: We included double-blind, randomised, placebo-controlled trials of vitamin D in children and adults with asthma evaluating exacerbation risk or asthma symptom control, or both. DATA COLLECTION AND ANALYSIS: Four review authors independently applied study inclusion criteria, extracted the data, and assessed risk of bias. We obtained missing data from the authors where possible. We reported results with 95% confidence intervals (CIs). The primary outcome was the incidence of severe asthma exacerbations requiring treatment with systemic corticosteroids. Secondary outcomes included the incidence of asthma exacerbations precipitating an emergency department visit or requiring hospital admission, or both, end-study childhood Asthma Control Test (cACT) or Asthma Control Test (ACT) scores, and end-study % predicted forced expiratory volume in one second (FEV1). We performed subgroup analyses to determine whether the effect of vitamin D on risk of asthma exacerbation was modified by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, form of vitamin D given, and age of participants. MAIN RESULTS: We included 20 studies in this review; 15 trials involving a total of 1155 children and five trials involving a total of 1070 adults contributed data to analyses. Participant ages ranged from 1 to 84 years, with two trials providing data specific to participants under five years (n = 69) and eight trials providing data specific to participants aged 5 to 16 (n = 766). Across the trials, 1245 participants were male and 1229 were female, with two studies not reporting sex distribution. Fifteen trials contributed to the primary outcome analysis of exacerbations requiring systemic corticosteroids. The duration of trials ranged from three to 40 months; all but two investigated effects of administering cholecalciferol (vitamin D3). As in the previous Cochrane Review, the majority of participants had mild to moderate asthma, and profound vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25 nmol/L) at baseline was rare. Administration of vitamin D or its hydroxylated metabolites did not reduce or increase the proportion of participants experiencing one or more asthma exacerbations treated with systemic corticosteroids (odds ratio (OR) 1.04, 95% CI 0.81 to 1.34; I2 = 0%; 14 studies, 1778 participants; high-quality evidence). This equates to an absolute risk of 226 per 1000 (95% CI 185 to 273) in the pooled vitamin D group, compared to a baseline risk of 219 participants per 1000 in the pooled placebo group. We also found no effect of vitamin D supplementation on the rate of exacerbations requiring systemic corticosteroids (rate ratio 0.86, 95% CI 0.62 to 1.19; I2 = 60%; 10 studies, 1599 participants; high-quality evidence), or the time to first exacerbation (hazard ratio 0.82, 95% CI 0.59 to 1.15; I2 = 22%; 3 studies, 850 participants; high-quality evidence). Subgroup analysis did not reveal any evidence of effect modification by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, or age. A single trial investigating administration of calcidiol reported a benefit of the intervention for the primary outcome of asthma control. Vitamin D supplementation did not influence any secondary efficacy outcome meta-analysed, which were all based on moderate- or high-quality evidence. We observed no effect on the incidence of serious adverse events (OR 0.89, 95% CI 0.56 to 1.41; I2 = 0%; 12 studies, 1556 participants; high-quality evidence). The effect of vitamin D on fatal asthma exacerbations was not estimable, as no such events occurred in any trial. Six studies reported adverse reactions potentially attributable to vitamin D. These occurred across treatment and control arms and included hypercalciuria, hypervitaminosis D, kidney stones, gastrointestinal symptoms and mild itch. In one trial, we could not ascertain the total number of participants with hypercalciuria from the trial report. We assessed three trials as being at high risk of bias in at least one domain; none of these contributed data to the analysis of the outcomes reported above. Sensitivity analyses that excluded these trials from each outcome to which they contributed did not change the null findings. AUTHORS' CONCLUSIONS: In contrast to findings of our previous Cochrane Review on this topic, this updated review does not find evidence to support a role for vitamin D supplementation or its hydroxylated metabolites to reduce risk of asthma exacerbations or improve asthma control. Participants with severe asthma and those with baseline 25(OH)D concentrations < 25 nmol/L were poorly represented, so further research is warranted here. A single study investigating effects of calcidiol yielded positive results, so further studies investigating effects of this metabolite are needed.

ANTECEDENTES: Desde la revisión Cochrane anterior sobre este tema en 2016, ha continuado el debate en torno a una posible función de la vitamina D en la reducción del riesgo de exacerbación del asma y la mejora de su control. Por lo tanto, se realizó un metanálisis actualizado para incluir los datos de los nuevos ensayos completados desde esta fecha. OBJETIVOS: Evaluar la eficacia y seguridad de la administración de vitamina D o sus metabolitos hidroxilados para reducir el riesgo de exacerbaciones graves del asma (definidas como aquellas que requieren tratamiento con corticosteroides sistémicos) y mejorar el control de sus síntomas. MÉTODOS DE BÚSQUEDA: Se buscó en el registro de ensayos del Grupo Cochrane de Vías respiratorias (Cochrane Airways Group) y en las listas de referencias de los artículos. Se estableció contacto con los autores de los estudios para identificar ensayos adicionales. Fecha de la última búsqueda: 8 de septiembre de 2022. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos doble ciego, aleatorizados, controlados con placebo de vitamina D en niños y adultos con asma que evaluaron el riesgo de exacerbación o el control de los síntomas del asma, o ambos. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Cuatro autores de la revisión aplicaron de forma independiente los criterios de inclusión de los estudios, extrajeron los datos y evaluaron el riesgo de sesgo. Cuando fue posible, se obtuvieron los datos faltantes a través de los autores de los estudios. Los resultados se informaron con intervalos de confianza (IC) del 95%. El desenlace principal fue la incidencia de exacerbaciones graves del asma que requirieron tratamiento con corticosteroides sistémicos. Los desenlaces secundarios incluyeron la incidencia de exacerbaciones del asma que precipitaron acudir al servicio de urgencias o requirieron ingreso hospitalario, o ambas, las puntuaciones de la childhood Asthma Control Test (cACT) o la Asthma Control Test (ACT) al final del estudio, y el % previsto de volumen espiratorio forzado en un segundo (VEF1) al final del estudio. Se realizaron análisis de subgrupos para determinar si el efecto de la vitamina D sobre el riesgo de exacerbación del asma se veía modificado por el estado inicial de vitamina D, la dosis de vitamina D, la frecuencia de la posología, la formulación de la vitamina D administrada y la edad de los participantes. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 20 estudios; 15 ensayos con un total de 1155 niños y cinco ensayos con un total de 1070 adultos aportaron datos para los análisis. Las edades de los participantes variaron entre 1 y 84 años, con dos ensayos que proporcionaron datos específicos de participantes menores de 5 años (n = 69) y ocho ensayos que proporcionaron datos específicos de participantes de 5 a 16 años (n = 766). En todos los ensayos, 1245 participantes eran hombres y 1229 mujeres, y dos estudios no informaron acerca de la distribución por sexos. Quince ensayos contribuyeron al análisis del desenlace principal: exacerbaciones que requirieron corticosteroides sistémicos. La duración de los ensayos fue de entre 3 y 40 meses; todos menos dos investigaron los efectos de la administración de colecalciferol (vitamina D3). Al igual que en la revisión Cochrane anterior, la mayoría de los participantes presentaban asma de leve a moderada y la deficiencia importante de vitamina D (25­hidroxivitamina D [25(OH)D] < 25 nmol/l) al inicio del estudio fue poco frecuente. La administración de vitamina D o sus metabolitos hidroxilados no redujo ni aumentó la proporción de participantes que presentaron una o más exacerbaciones del asma tratada con corticosteroides sistémicos (odds ratio [OR] 1,04; IC del 95%: 0,81 a 1,34; I2 = 0%; 14 estudios, 1778 participantes; evidencia de calidad alta). Esto equivale a un riesgo absoluto de 226 por cada 1000 (IC del 95%: 185 a 273) en el grupo de vitamina D agrupado, en comparación con un riesgo inicial de 219 participantes por cada 1000 en el grupo placebo agrupado. Tampoco se encontraron efectos de la administración de suplementos de vitamina D sobre la tasa de exacerbaciones que requirieron corticosteroides sistémicos (cociente de tasas 0,86; IC del 95%: 0,62 a 1,19; I2 = 60%; 10 estudios, 1599 participantes; evidencia de calidad alta) ni sobre el tiempo transcurrido hasta la primera exacerbación (cociente de riesgos instantáneos 0,82; IC del 95%: 0,59 a 1,15; I2 = 22%; tres estudios, 850 participantes; evidencia de calidad alta). El análisis de subgrupos no reveló una evidencia de modificación del efecto en función del estado inicial de vitamina D, la dosis de vitamina D, la frecuencia de la posología ni la edad. Un único ensayo que investigó la administración de calcidiol informó sobre un efecto beneficioso de la intervención en el desenlace principal de control del asma. La administración de suplementos de vitamina D no influyó en ninguno de los desenlaces secundarios de eficacia metanalizados, todos ellos basados en evidencia de calidad moderada o alta. No se observaron efectos sobre la incidencia de eventos adversos graves (OR 0,89; IC del 95%: 0,56 a 1,41; I2 = 0%; 12 estudios, 1556 participantes; evidencia de calidad alta). No fue posible determinar el efecto de la vitamina D sobre las exacerbaciones mortales del asma ya que no se produjeron tales eventos en ningún ensayo. Seis estudios informaron sobre la presencia de reacciones adversas potencialmente atribuibles a la vitamina D. Estas se dieron en los grupos de tratamiento y control e incluyeron hipercalciuria, hipervitaminosis D, cálculos renales, síntomas gastrointestinales y prurito leve. En un ensayo, no fue posible determinar el número total de participantes con hipercalciuria a partir del informe del ensayo. Tres ensayos se consideraron con alto riesgo de sesgo en al menos un dominio; ninguno de ellos aportó datos al análisis de los desenlaces informados anteriormente. Los análisis de sensibilidad que excluyeron estos ensayos de cada desenlace al que contribuyeron no cambiaron los hallazgos nulos. CONCLUSIONES DE LOS AUTORES: En contraposición con los hallazgos de la revisión Cochrane anterior sobre este tema, esta revisión actualizada no encuentra evidencia que respalde una función de los suplementos de vitamina D o sus metabolitos hidroxilados en la reducción del riesgo de exacerbaciones del asma o la mejoría del control del asma. Los participantes con asma grave y aquellos con concentraciones iniciales de 25(OH)D < 25 nmol/l estuvieron escasamente representados, por lo que se justifica la realización de más estudios de investigación. Un único estudio que investigó los efectos del calcidiol proporcionó resultados positivos, por lo que se necesitan más estudios que investiguen los efectos de este metabolito.

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.

Calcium and vitamin D for increasing bone mineral density in premenopausal women.

BACKGROUND: Osteoporosis is a condition where bones become fragile due to low bone density and impaired bone quality. This results in fractures that lead to higher morbidity and reduced quality of life. Osteoporosis is considered a major public health concern worldwide. For this reason, preventive measurements need to be addressed throughout the life course. Exercise and a healthy diet are among the lifestyle factors that can help prevent the disease, the latter including intake of key micronutrients for bone, such as calcium and vitamin D. The evidence on whether supplementation with calcium and vitamin D improves bone mineral density (BMD) in premenopausal women is still inconclusive. In this age group, bone accrual is considered to be the goal of supplementation, so BMD is relevant for the future stages of life. OBJECTIVES: To evaluate the benefits and harms of calcium and vitamin D supplementation, alone or in combination, to increase the BMD, reduce fractures, and report the potential adverse events in healthy premenopausal women compared to placebo. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search was 12 April 2022. SELECTION CRITERIA: We included randomised controlled trials in healthy premenopausal women (with or without calcium or vitamin D deficiency) comparing supplementation of calcium or vitamin D (or both) at any dose and by any route of administration versus placebo for at least three months. Vitamin D could have been administered as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Outcomes included total hip bone mineral density (BMD), lumbar spine BMD, quality of life, new symptomatic vertebral fractures, new symptomatic non-vertebral fractures, withdrawals due to adverse events, serious adverse events, all reported adverse events and additional withdrawals for any reason. MAIN RESULTS: We included seven RCTs with 941 participants, of whom 138 were randomised to calcium supplementation, 110 to vitamin D supplementation, 271 to vitamin D plus calcium supplementation, and 422 to placebo. Mean age ranged from 18.1 to 42.1 years. Studies reported results for total hip or lumbar spine BMD (or both) and withdrawals for various reasons, but none reported fractures or withdrawals for adverse events or serious adverse events. Results for the reported outcomes are presented for the three comparisons: calcium versus placebo, vitamin D versus placebo, and calcium plus vitamin D versus placebo. In all comparisons, there was no clinical difference in outcomes, and the certainty of the evidence was moderate to low. Most studies were at risk of selection, performance, detection, and reporting biases. Calcium versus placebo Four studies compared calcium versus placebo (138 participants in the calcium group and 123 in the placebo group) with mean ages from 18.0 to 47.3 years. Calcium supplementation may have little to no effect on total hip or lumbar spine BMD after 12 months in three studies and after six months in one study (total hip BMD: mean difference (MD) -0.04 g/cm2, 95% confidence interval (CI) -0.11 to 0.03; I2 = 71%; 3 studies, 174 participants; low-certainty evidence; lumbar spine BMD: MD 0 g/cm2, 95% CI -0.06 to 0.06; I2 = 71%; 4 studies, 202 participants; low-certainty evidence). Calcium alone supplementation does not reduce or increase the withdrawals in the trials (risk ratio (RR) 0.78, 95% CI 0.52 to 1.16; I2 = 0%; 4 studies, 261 participants: moderate-certainty evidence). Vitamin D versus placebo Two studies compared vitamin D versus placebo (110 participants in the vitamin D group and 79 in the placebo group), with mean ages from 18.0 to 32.7 years. These studies reported lumbar spine BMD as a mixture of MDs and percent of change and we were unable to pool the results. In the original studies, there were no differences in lumbar BMD between groups. Vitamin D alone supplementation does not reduce or increase withdrawals for any reason between groups (RR 0.74, 95% CI 0.46 to 1.19; moderate-certainty evidence). Calcium plus vitamin D versus placebo Two studies compared calcium plus vitamin D versus placebo (271 participants in the calcium plus vitamin D group and 270 in the placebo group; 220 participants from Woo 2007 and 50 participants from Islam 2010). The mean age range was 18.0 to 36 years. These studies measured different anatomic areas, one study reported total hip BMD and the other study reported lumbar spine BMD; therefore, data were not pooled for this outcome. The individual studies found no difference between groups in percent of change on total hip BMD (-0.03, 95% CI -0.06 to 0; moderate-certainty evidence), and lumbar spine BMD (MD 0.01, 95% CI -0.01 to 0.03; moderate-certainty evidence). Calcium plus vitamin D supplementation may not reduce or increase withdrawals for any reason (RR 0.82, 95% CI 0.29 to 2.35; I2 = 72%; 2 studies, 541 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: Our results do not support the isolated or combined use of calcium and vitamin D supplementation in healthy premenopausal women as a public health intervention to improve BMD in the total hip or lumbar spine, and therefore it is unlikely to have a benefit for the prevention of fractures (vertebral and non-vertebral). The evidence found suggests that there is no need for future studies in the general population of premenopausal women; however, studies focused on populations with a predisposition to diseases related to bone metabolism, or with low bone mass or osteoporosis diagnosed BMD would be useful.

XCHT alleviates the pancreatic fibrosis via VDR/NLRP3 signaling pathway in a mouse model of CP.

ETHNOPHARMACOLOGICAL RELEVANCE: Xiao Chai Hu Tang (XCHT) derived from the classic medical book Shang Han Lun (Treatise on Febrile Diseases) in the Eastern Han Dynasty, which has been widely used in China and other Asian countries for the treatment of inflammation and fibrosis of chronic pancreatitis (CP), but the therapeutic mechanism of XCHT in pancreatic fibrosis remains unclear. AIM OF THE STUDY: This study aimed to evaluate the intervention effects and explore pharmacological mechanism of XCHT on inflammation and fibrosis in cerulein-induced CP model. MATERIALS AND METHODS: Fifty male C57BL/6 mice were randomly divided into five main groups, 10 animals in each: Control, CP model (50 µg/kg cerulein), high dose XCHT-treated CP group (60 g/kg XCHT), medium dose XCHT-treated CP group (30 g/kg XCHT) and low dose XCHT-treated CP group (15 g/kg XCHT). Different doses of XCHT were given to mice by gavage twice a day for 2 weeks after the CP model induction. Pancreatic tissues were harvested and the pancreatic inflammation and fibrosis were evaluated by histological score, Sirius red staining, and alpha-smooth muscle actin (α-SMA) immunohistochemical staining. ELISA, IHC and RT-qPCR were performed to detect the expression of Vitamin D3 (VD3) and Vitamin D receptor (VDR) in serum and pancreatic tissues, respectively. The expressions of NLRP3 inflammasome related genes and molecules were assayed by WB, IHC and RT-qPCR. RESULTS: The pathohistological results demonstrated that XCHT markedly inhibited the fibrosis and chronic inflammation of cerulein-induced CP, indicated by reduction of collagen I, collagen III, α-SMA, and NLRP3 expressions. XCHT significantly increased VD3 and VDR expression while reduced the pancreatic NLRP3 expression. Correspondingly, XCHT decreased the levels of NLRP3 downstream targets IL-1ß, TNF-α and IL-6. CONCLUSIONS: These results revealed that XCHT suppressed the pancreatic fibrosis and chronic inflammation in cerulein-induced CP model by enhancing the VD3/VDR expression and inhibiting the secretion of NLRP3-assoicated inflammatory factors.

Vitamin D Toxicity from an Unusual and Unexpected Source: A Report of 2 Cases.

INTRODUCTION: Hypervitaminosis D is a relatively uncommon etiology of hypercalcemia. Toxicity is usually caused by very high doses, mostly secondary to erroneous prescription or administration of vitamin D, and less commonly, contaminated foods or manufacturing errors of vitamin D-containing supplements. CASE PRESENTATION: A 16-year-old male, previously healthy, presented with 2-week history of nonspecific symptoms (fatigue, gastrointestinal complaints). Investigations showed acute kidney injury and hypercalcemia (total calcium 3.81 mmol/L). Further diagnostic workup revealed markedly elevated 25-hydroxyvitamin D levels (1,910 nmol/L). He denied taking any vitamin D supplements; however, he reported consumption of creatine and protein supplements. Mass spectrometry analysis of the creatine supplement estimated a vitamin D content of 425,000 IU per serving (100 times the upper tolerable daily dose). A few months later, another previously healthy adolescent presented with severe hypercalcemia and acute kidney injury secondary to hypervitaminosis D. He was also using a creatine supplement, from the same manufacturer brand and lot. Both patients were treated with intravenous hydration, calcitonin, and pamidronate. They maintained normocalcemia after their initial presentation but required low-calcium diets and laboratory testing for months after this exposure. DISCUSSION/CONCLUSION: We present 2 cases of hypervitaminosis D caused by a manufacturing error of a natural health product which did not claim to contain vitamin D. The use of dietary supplements is highly prevalent; this should be incorporated while taking medical history, and considered a potential source of toxicity when an alternative source cannot be found, regardless of the product label.

Hypercalcemia: A Review.

Importance: Hypercalcemia affects approximately 1% of the worldwide population. Mild hypercalcemia, defined as total calcium of less than 12 mg/dL (<3 mmol/L) or ionized calcium of 5.6 to 8.0 mg/dL (1.4-2 mmol/L), is usually asymptomatic but may be associated with constitutional symptoms such as fatigue and constipation in approximately 20% of people. Hypercalcemia that is severe, defined as total calcium of 14 mg/dL or greater (>3.5 mmol/L) or ionized calcium of 10 mg/dL or greater (≥2.5 mmol/L) or that develops rapidly over days to weeks, can cause nausea, vomiting, dehydration, confusion, somnolence, and coma. Observations: Approximately 90% of people with hypercalcemia have primary hyperparathyroidism (PHPT) or malignancy. Additional causes of hypercalcemia include granulomatous disease such as sarcoidosis, endocrinopathies such as thyroid disease, immobilization, genetic disorders, and medications such as thiazide diuretics and supplements such as calcium, vitamin D, or vitamin A. Hypercalcemia has been associated with sodium-glucose cotransporter 2 protein inhibitors, immune checkpoint inhibitors, denosumab discontinuation, SARS-CoV-2, ketogenic diets, and extreme exercise, but these account for less than 1% of causes. Serum intact parathyroid hormone (PTH), the most important initial test to evaluate hypercalcemia, distinguishes PTH-dependent from PTH-independent causes. In a patient with hypercalcemia, an elevated or normal PTH concentration is consistent with PHPT, while a suppressed PTH level (<20 pg/mL depending on assay) indicates another cause. Mild hypercalcemia usually does not need acute intervention. If due to PHPT, parathyroidectomy may be considered depending on age, serum calcium level, and kidney or skeletal involvement. In patients older than 50 years with serum calcium levels less than 1 mg above the upper normal limit and no evidence of skeletal or kidney disease, observation may be appropriate. Initial therapy of symptomatic or severe hypercalcemia consists of hydration and intravenous bisphosphonates, such as zoledronic acid or pamidronate. In patients with kidney failure, denosumab and dialysis may be indicated. Glucocorticoids may be used as primary treatment when hypercalcemia is due to excessive intestinal calcium absorption (vitamin D intoxication, granulomatous disorders, some lymphomas). Treatment reduces serum calcium and improves symptoms, at least transiently. The underlying cause of hypercalcemia should be identified and treated. The prognosis for asymptomatic PHPT is excellent with either medical or surgical management. Hypercalcemia of malignancy is associated with poor survival. Conclusions and Relevance: Mild hypercalcemia is typically asymptomatic, while severe hypercalcemia is associated with nausea, vomiting, dehydration, confusion, somnolence, and coma. Asymptomatic hypercalcemia due to primary hyperparathyroidism is managed with parathyroidectomy or observation with monitoring, while severe hypercalcemia is typically treated with hydration and intravenous bisphosphonates.

Is Melatonin the "Next Vitamin D"?: A Review of Emerging Science, Clinical Uses, Safety, and Dietary Supplements.

Melatonin has become a popular dietary supplement, most known as a chronobiotic, and for establishing healthy sleep. Research over the last decade into cancer, Alzheimer's disease, multiple sclerosis, fertility, PCOS, and many other conditions, combined with the COVID-19 pandemic, has led to greater awareness of melatonin because of its ability to act as a potent antioxidant, immune-active agent, and mitochondrial regulator. There are distinct similarities between melatonin and vitamin D in the depth and breadth of their impact on health. Both act as hormones, affect multiple systems through their immune-modulating, anti-inflammatory functions, are found in the skin, and are responsive to sunlight and darkness. In fact, there may be similarities between the widespread concern about vitamin D deficiency as a "sunlight deficiency" and reduced melatonin secretion as a result of "darkness deficiency" from overexposure to artificial blue light. The trend toward greater use of melatonin supplements has resulted in concern about its safety, especially higher doses, long-term use, and application in certain populations (e.g., children). This review aims to evaluate the recent data on melatonin's mechanisms, its clinical uses beyond sleep, safety concerns, and a thorough summary of therapeutic considerations concerning dietary supplementation, including the different formats available (animal, synthetic, and phytomelatonin), dosing, timing, contraindications, and nutrient combinations.

Too much of a good thing: A case series of rare yet pertinent causes of hypercalcaemia and acute kidney injury.

Calcium compounds and vitamin D supplements are readily available as over-the-counter preparations. Whilst integral in maintaining calcium homeostasis in certain patients, excess exogenous intake of these preparations can have deleterious effects, particularly in terms of renal function. We look at the cases of two patients, aged 52 and 34, who were referred into hospital with hypercalcaemia and acute kidney injury (AKI). Both individuals reported regular and prolonged self-medication with unregulated over-the-counter supplements containing calcium carbonate and vitamin D, respectively. Prompt investigation and treatment enabled an element of reversibility of the AKI in both the cases, with further improvement in renal function over time. We emphasise the importance of recognising the overuse of exogenous vitamin D supplements and calcium compounds as rare yet treatable causes of AKI associated with hypercalcaemia and discuss how raising public awareness into the risks posed by self-medication of over-the-counter medicines is paramount.

Serum Vitamin D Level and Efficacy of Vitamin D Supplementation in Children with Atopic Dermatitis: A Systematic Review and Meta-analysis.

Background: The relationship between vitamin D and atopic dermatitis (AD) is controversial. This meta-analysis is aimed at exploring vitamin D level and its deficiency in pediatric AD and at evaluating the efficacy of vitamin D supplementation. Methods: PubMed, Medline, Embase, Ovid, Cochrane Library, ISI Web of Science, and ClinicalTrials were searched. Binary variables and continuous variables were measured by odds ratio (OR) and mean difference (MD) with 95% confidence intervals, respectively. The modified Jadad scale, Newcastle-Ottawa Scale (NOS), and Cochrane's bias risk tools were used to evaluate study quality and the risk of bias of eligible studies, respectively. Results: A total of 22 literature were included in the analysis. Serum 25 (OH) D level in pediatric AD patients was significantly lower than that of the control group with a combined MD value of -8.18 (95% CI: -13.15, -3.22). Patients with AD were more prone to develop vitamin D deficiency with a combined OR value of 2.17 (95% CI: 1.15, 4.11). According to the score of SCORAD, the level of serum 25 (OH) D level in patients with severe AD was significantly lower than that in patients with mild AD (combined MD = 9.23, 95% CI: 6.92, 11.55). Both self-control studies and randomized controlled trials showed improved SCORAD score and EASI score after vitamin D supplementation. Conclusion: This meta-analysis showed lower serum 25 (OH) D level and increased risk of vitamin D deficiency in pediatric AD patients as compared with healthy controls. The serum 25 (OH) D level in severe AD patients was significantly lower than that in the mild AD patients. The SCORAD and EASI score improved after vitamin D supplementation, suggesting its beneficial effect to AD patients. At the same time, more homogeneous studies are needed to reduce confounding factors and further evaluate the impact of vitamin D treatment on the outcome of AD patients.

Association Between Vitamin D Supplementation and Statin-Associated Muscle Symptoms: A Systematic Review.

INTRODUCTION: Although low vitamin D levels are associated with statin-associated muscle symptoms (SAMS), it remains unclear if vitamin D supplementation leads to symptom improvement. AIM: We performed a systematic review to evaluate the association of vitamin D supplementation with resolution of SAMS. METHODS: We searched Medline (PubMed), Embase and Cochrane Library till 12 December 2021. Full length articles that reported on the association between vitamin D supplementation in adult patients with SAMS were included. RESULTS: We identified 8 interventional studies comprising 669 participants. Majority of the participants were of Caucasian ethnicity and the mean age of participants ranged from 59.5 to 64.8 years old. The studies recruited patients with initial mean pre-treatment vitamin D levels ranging from 17.8 to 22.0ng/mL. Follow up duration ranged from 2 to 24 months and mean post-treatment vitamin D levels ranged from 34.3 to 56.0ng/mL. We found that vitamin D supplementation was associated with improved statin tolerance in 509 out of 606 (83.9%) patients across the 7 studies which reported patient numbers after supplementation (95% CI = 0.81-0.87, I2 = 72% n = 7). None of the studies were randomized controlled trials (RCTs) and hence placebo effect of vitamin D could not be ruled out. Nocebo effect of statin was also not assessed by any of the studies. CONCLUSION: Vitamin D supplementation in patients with mild-moderate vitamin D insufficiency was associated with improvement of SAMS. However, quantitative efficacy analysis was not possible and this observed association is likely confounded by nocebo and placebo effects. RCTs are required to conclusively assess the utility of vitamin D supplementation in improving SAMS.

Nephrocalcinosis in children who received high-dose vitamin D.

BACKGROUND: Vitamin D supplements are readily available as over-the-counter preparations. However, although rare, cases of vitamin D overdose still occur and are associated with nephrocalcinosis and life-threatening hypercalcemia. Errors in manufacturing of nutritional supplements may be a cause of vitamin D intoxication in children. This study aimed to identify factors associated with vitamin D overdose-related nephrocalcinosis in children due to manufacturing errors in supplements. METHODS: This retrospective study reviewed medical charts of pediatric patients with non-registered supplement-related vitamin D overdose at a tertiary referral hospital between 2006 and 2011. Clinical and laboratory characteristics of patients with or without nephrocalcinosis were evaluated. Receiver operating characteristics curve and area under the receiver operating characteristics curve were used to determine the most predictive value of each characteristic. RESULTS: A total of 44 patients (males: 29; age: 7-62 months) were included. Age ≤ 16.5 months, body weight ≤ 10.25 kg, body height ≤ 78.5 cm, body surface area (BSA) ≤ 0.475 m2, 25-hydroxyvitamin D3 ≥ 143 ng/mL, and calcium ≥ 10.65 mg/dL were predictive of developing nephrocalcinosis with a sensitivity and specificity of > 60%. Univariant analysis revealed that BSA was the most significant anthropometric prognostic factor (odds ratio: 12.09; 95% confidence interval: 2.61-55.72; P = 0.001). CONCLUSIONS: Children with smaller BSAs were more vulnerable to high-dose vitamin D3-related nephrocalcinosis. Physicians and parents should be aware of the potential adverse effects of vitamin D overdose in children. A higher resolution version of the Graphical abstract is available as Supplementary information.

High-dose vitamin D substitution in patients with COVID-19: study protocol for a randomized, double-blind, placebo-controlled, multi-center study-VitCov Trial.

BACKGROUND: The coronavirus disease 19 (COVID-19) pandemic has caused millions of deaths, and new treatments are urgently needed. Factors associated with a worse COVID-19 prognosis include old age (> 65 years), ethnicity, male sex, obesity, and people with comorbidities. Furthermore, vitamin D deficiency was reported as a predictor of poor prognosis in patients with acute respiratory failure due to COVID-19. According to a recent clinical case series, vitamin D deficiency is a modifiable risk factor, which has the prospect of reducing hospital stay, intensive care, and fatal outcomes. Vitamin D has potent immunomodulatory properties, and its supplementation might improve important outcomes in critically ill and vitamin D-deficient COVID-19 patients. Despite the evidence that supports an association between vitamin D deficiency and COVID-19 severity, there is uncertainty about the direct link. Therefore, the aim of the trial is to assess if high-dose vitamin D supplementation has a therapeutic effect in vitamin D-deficient patients with COVID-19. METHODS: As the trial design, a randomized, placebo-controlled, double-blind, multi-center approach was chosen to compare a high single dose of vitamin D (140,000 IU) followed by treatment as usual (TAU) (VitD + TAU) with treatment as usual only (placebo + TAU) in patients with COVID-19 and vitamin D deficiency. DISCUSSION: Vitamin D substitution in patients with COVID-19 and vitamin D deficiency should be investigated for efficacy and safety. The study aim is to test the hypothesis that patients with vitamin D deficiency suffering from COVID-19 treated under standardized conditions in hospital will recover faster when additionally treated with high-dose vitamin D supplementation. Latest studies suggest that vitamin D supplementation in patients with COVID-19 is highly recommended to positively influence the course of the disease. With this randomized controlled trial, a contribution to new treatment guidelines shall be made. TRIAL REGISTRATION: ClinicalTrials.gov NCT04525820 and SNCTP 2020-01401.

Vitamin D and the risk of latent tuberculosis infection: a systematic review and meta-analysis.

OBJECTIVE: Latent tuberculosis infection (LTBI) may be a risk of developing tuberculosis (TB) and thus a health hazard. The aim of this meta-analysis is to explore the association between vitamin D and LTBI. METHODS: Databases including PubMed, Embase, Scopus, and ProQuest were electronically searched to identify observational or interventional studies that reported the association between vitamin D and LTBI. The retrieval time is limited from inception to 30 September 2021. Two reviewers independently screened literature, extracted data, and assessed risk bias of included studies. Meta-analysis was performed by using STATA 12.0 software. RESULTS: A total of 5 studies involving 2 case-control studies and 3 cohort studies were included. The meta-analysis result showed that the risk of LTBI among individuals was not associated with high vitamin D level (OR 0.51, 95% CI 0.05-5.65, P = 0.58). The result from cohort studies also suggested that relatively high vitamin D level was not a protective factor for LTBI (RR = 0.56, 95%CI 0.19-1.67, P = 0.300). CONCLUSIONS: Our meta-analysis suggested that serum vitamin D levels were not associated with incidence of LTBI, and relatively high serum vitamin D level was not a protective factor for LTBI. Further RCTs are needed to verify whether sufficient vitamin D levels and vitamin D supplementation reduces the risk of LTBI.