Weekly Vitamin D Supplementation to Prevent Acute Respiratory Infections in Young Children at Different Latitudes: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the effectiveness of weekly vitamin D supplementation in reducing the number of acute respiratory infections (ARI) in preschool children. STUDY DESIGN: Randomized, double-blind, placebo-controlled trial in 303 children aged 1.5-3.5 years from 2014 to 2105 in 3 Chilean cities at different latitudes: Santiago (33°S, n = 101), Talcahuano (37°S, n = 103), and Punta Arenas (53°S, n = 99). Participants were allocated (1:1:1) to receive placebo, cholecalciferol (vitamin D3 (VD3)) 5600 IU/week (low-dose), or 11 200 IU/week (high-dose) for 6 months. Primary outcome was parent-reported number of ARI; secondary outcomes included number of ARI hospitalizations, change of serum 25-hydroxyvitamin D (25(OH)D) and LL-37/cathelicidin levels, and adverse events. RESULTS: The mean age of participants was 26 ± 6 months; 45% were female. Baseline 25(OH)D was 24.9 ± 6.1 ng/ml, with 23% having 25(OH)D <20 ng/ml. No significant baseline clinical or laboratory differences were observed among groups. Overall, 64% (n = 194) completed study participation, without baseline differences between subjects lost to follow-up vs those completing participation or differences in completion rates across groups. After 6 months, a dose-dependent increase in serum 25(OH)D was observed from the VD3 intervention (P < .001), with a higher proportion of subjects ending the trial with 25(OH)D <20 ng/ml in the placebo group (30.8%) vs the low-dose (7.4%) and high-dose groups (5.1%). However, no group differences were observed in number of ARI (P = .85), ARI hospitalizations (P = .20), LL-37/cathelicidin change (P = .30), or adverse events (P = .41). CONCLUSIONS: While weekly VD3 supplementation, in doses equivalent to 800 IU and 1600 IU daily, was associated with improved 25(OH)D levels in preschoolers, we did not find a reduced number of ARI in this sample.

Association of Vitamin A and D Deficiencies with Infectious Outcomes in Children Undergoing Intensive Induction Therapy for Acute Lymphoblastic Leukemia.

OBJECTIVE: To evaluate the association between deficiency of vitamin A or D at diagnosis of pediatric acute lymphoblastic leukemia (ALL) and subsequent infectious complications during induction therapy. STUDY DESIGN: We conducted an institutional review board-approved, retrospective cohort study of children with newly diagnosed ALL from 2007 to 2017 at St. Jude Children's Research Hospital. We measured vitamin D, vitamin D binding protein, retinol binding protein as a surrogate for vitamin A, and immunoglobulin isotypes in serum obtained at ALL diagnosis, and we assessed the association between vitamin deficiencies or levels and infection-related complications during the 6-week induction phase using Cox regression models. RESULTS: Among 378 evaluable participants, vitamin A and D deficiencies were common (43% and 17%, respectively). Vitamin D deficiency was associated with higher risks of febrile neutropenia (adjusted hazard ratio [aHR], 1.7; P = .0072), clinically documented infection (aHR, 1.73; P = .025), and likely bacterial infection (aHR, 1.86; P = .008). Conversely, vitamin A deficiency was associated solely with a lower risk of sepsis (aHR, 0.19; P = .027). CONCLUSIONS: In this retrospective study, vitamin D deficiency was associated with an increased risk of common infection-related complications during induction therapy for ALL. Additional studies are warranted to evaluate whether vitamin D supplementation could mitigate this effect.

Vitamin D Metabolites Before and After Kidney Transplantation in Patients Who Are Anephric.

RATIONALE & OBJECTIVE: Kidneys are vital for vitamin D metabolism, and disruptions in both production and catabolism occur in chronic kidney disease. Although vitamin D activation occurs in numerous tissues, the kidneys are the most relevant source of circulating active vitamin D. This study investigates extrarenal vitamin D activation and the impact of kidney transplantation on vitamin D metabolism in patients who are anephric. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: Adult patients with previous bilateral nephrectomy (anephric) not receiving active vitamin D therapy evaluated at the time of (N=38) and 1 year after (n=25) kidney transplantation. ANALYTICAL APPROACH: Chromatography with tandem mass spectrometry was used to measure vitamin D metabolites. Activity of CYP24A1 [24,25(OH)2D/25(OH)D] and CYP27B1 [1α,25(OH)2D/25(OH)D] is expressed as metabolic ratios. Differences between time points were evaluated by paired t-test or Wilcoxon matched-pairs signed-rank test. RESULTS: At time of transplantation, 1α,25(OH)2D was detectable in all patients (4-36pg/mL). There was a linear relationship between 25(OH)D and 1α,25(OH)2D levels (r=0.58, P<0.001), with 25(OH)D explaining 34% of the variation in 1α,25(OH)2D levels. There were no associations between 1α,25(OH)2D and biointact parathyroid hormone (PTH) or fibroblast growth factor 23 (FGF-23). One year after transplantation, 1α,25(OH)2D levels recovered (+205%), and CYP27B1 activity increased (+352%). Measures of vitamin D catabolism, 24,25(OH)2D and CYP24A1 activity increased 3- to 5-fold. Also, at 12 months after transplantation, 1α,25(OH)2D was positively correlated with PTH (ρ=0.603, P=0.04) but not with levels of 25(OH)D or FGF-23. LIMITATIONS: Retrospective, observational study design with a small cohort size. CONCLUSIONS: Low-normal levels of 1α,25(OH)2D was demonstrated in anephric patients, indicating production outside the kidneys. This extrarenal CYP27B1 activity may be more substrate driven than hormonally regulated. Kidney transplantation seems to restore kidney CYP27B1 and CYP24A1 activity, as evaluated by vitamin D metabolic ratios, resulting in both increased vitamin D production and catabolism. These findings may have implications for vitamin D supplementation strategies in the setting of kidney failure and transplantation. PLAIN-LANGUAGE SUMMARY: Vitamin D activation occurs in multiple tissues, but the kidneys are considered the only relevant source of circulating levels. This study investigates vitamin D activation outside the kidneys by measuring vitamin D metabolites in 38 patients without kidneys. Active vitamin D was detectable in all patients, indicating production outside of the kidneys. There was a strong relationship between active and precursor vitamin D levels, but no association with mineral metabolism hormones, indicating that vitamin D production was more substrate dependent than hormonally regulated. One year after kidney transplantation, active vitamin D levels increased 2-fold and breakdown products increased 3-fold, indicating that production and degradation of the hormone recovers after kidney transplantation. These findings are relevant for future research into vitamin D supplementation in kidney failure.

The yield of routine laboratory examination in osteoporosis evaluation in primary care.

This study evaluated the yield of routine laboratory examination in a large population of older women in primary care. The prevalence of laboratory abnormalities was low and the clinical consequences in follow-up were limited. There was a weak association of laboratory abnormalities with osteoporosis but no association with vertebral fractures and recent fractures. PURPOSE: Most osteoporosis guidelines advice routine laboratory examination. We have investigated the yield of laboratory examinations in facture risk evaluation of elderly women in primary care. METHODS: We assessed the prevalence of laboratory abnormalities and their association with risk factors for fractures, recent fractures, low bone mineral density (BMD), and prevalent vertebral fracture in 8996 women ≥ 65 years of age participating in a primary care fracture risk screening study. In a sample of 2208 of these participants, we also evaluated the medical consequences in the medical records during a follow-up period of ≥ 1 year. RESULTS: Vitamin D deficiency (< 30 nmol/L) was present in 13% and insufficiency (< 50 nmol/L) in 43% of the study sample. The prevalence of other laboratory abnormalities (ESR, calcium, creatinine, FT4) was 4.6% in women with risk factors for fractures, 6.1% in women with low BMD (T-score ≤ - 2.5), 6.0% after a prevalent vertebral fracture, 5.2% after a recent fracture and 2.6% in the absence of important risk factors for fractures. Laboratory abnormalities other than vitamin D were associated with low BMD (OR 1.4, 95%CI 1.1-1.8) but not with prevalent vertebral fractures nor recent fractures. Low BMD was associated with renal failure (OR 2.0, 95%CI 1.3-3.4), vitamin D insufficiency (OR 1.2, 95%CI 1.0-1.3) and deficiency (OR 1.3, 95%CI 1.1-.5). In the follow-up period, 82% of the laboratory abnormalities did not result in a new diagnosis or treatment reported in the medical records. CONCLUSIONS: We identified a low prevalence of laboratory abnormalities in a primary care population of older women and the majority of these findings had no medical consequences.

Severe vitamin D deficiency increases the risk of severe cutaneous adverse reactions.

Vitamin D deficiency has been reported to be associated with allergic diseases and dermatological disorders. We investigated the role of vitamin D in drug-induced non-immediate hypersensitivity reactions by measuring serum vitamin D levels in 60 patients diagnosed with non-immediate drug hypersensitivity reactions and in 60 patients who tolerated the same medication without any allergic reactions. The results showed that serum vitamin D levels were significantly lower in patients with severe cutaneous adverse reactions (SCARs) (13.56 ± 6.23 ng/mL) compared to patients with mild reactions (17.50 ± 7.49 ng/mL) and the drug-tolerant control group (17.42 ± 7.28 ng/mL), with p values of 0.031 and 0.015, respectively. The proportion of severe vitamin D deficiency (< 10 ng/mL) was much higher in SCAR patients compared to drug-tolerant subjects (36.7% vs. 11.7%, p value = 0.005). After adjusting for age, gender, region of residence, and concurrent illnesses, patients with severe vitamin D deficiency had significantly increased in-hospital mortality (odds ratio 16.04; 95% CI, 1.25-206.12, p value = 0.03). In conclusion, the risk of developing SCARs and in-hospital mortality was increased in patients with severe vitamin D deficiency. Further investigations should be conducted to elucidate the role of vitamin D in the development of SCARs.

Serum 25-Hydroxyvitamin D and Risk of Disability in Activities of Daily Living among the Oldest-Old: An Observational and Mendelian Randomization Study.

BACKGROUND: Vitamin D deficiency and disability are both prevalent among older adults. However, the association between them has rarely been investigated in the oldest-old subjects (aged ≥80 y), and the causality remains unclear. OBJECTIVE: This study aimed to elucidate the causal effect of vitamin D on the incident risk of disability in activities of daily living (ADL) among Chinese oldest-old based on the 2012-2018 Chinese Healthy Ageing and Biomarkers Cohort Study. METHODS: Serum 25-hydroxyvitamin D [25(OH)D] concentrations and ADL status at baseline and follow-up interviews were documented. Cox regression models were applied among 1427 oldest-old (mean age, 91.2 y) with normal baseline ADL status. One sample Mendelian randomization (MR) analyses were performed on a subset of 941 participants with qualified genetic data, using a 25(OH)D-associated genetic risk score as the genetic instrument. RESULTS: During a median follow-up of 3.4 y, 231 participants developed disability in ADL. Serum 25(OH)D concentration was inversely associated with the risk of disability in ADL [per 10 nmol/L increase hazard ratio (HR) 0.85; 95% CI: 0.75, 0.96]. Consistent results from MR analyses showed that a 10 nmol/L increment in genetically predicted 25(OH)D concentration corresponded to a 20% reduced risk of ADL disability (HR 0.80; 95% CI: 0.68, 0.94). Nonlinear MR demonstrated a monotonic declining curve, with the HRs exhibiting a more pronounced reduction among individuals with 25(OH)D concentrations below 50 nmol/L. Subgroup analyses showed that the associations were more distinct among females and those with poorer health conditions. CONCLUSIONS: Our study supports an inverse causal relationship between serum 25(OH)D concentration and the risk of disability in ADL among Chinese oldest-old. This protective effect was more distinct, especially for participants with vitamin D deficiency. Appropriate measures for improving vitamin D might help reduce the incidence of physical disability in this specific age group.

Vitamin D deficiency and effect of treatment on seizure frequency and quality of life parameters in patients with drug-resistant epilepsy: A randomized clinical trial.

OBJECTIVE: This study was undertaken to assess the effect of treatment of vitamin D deficiency in drug-resistant epilepsy. METHODS: We conducted a multicenter, double-blind, placebo-controlled, randomized clinical trial, including patients aged ≥15 years with drug-resistant focal or generalized epilepsy. Patients with 25-hydroxyvitamin D (25[OH]D) < 30 ng/mL were randomized to an experimental group (EG) receiving vitamin D3 (cholecalciferol, 100 000 IU, five doses in 3 months) or a control group (CG) receiving matched placebo. During the open-label study, EG patients received 100 000 IU/month for 6 months, whereas CG patients received five doses in 3 months then 1/month for 3 months. Monitoring included seizure frequency (SF), 25(OH)D, calcium, albumin, creatinine assays, and standardized scales for fatigue, anxiety-depression, and quality of life (Modified Fatigue Impact Scale [M-FIS], Hospital Anxiety and Depression Scale, Quality of Life in Epilepsy [QOLIE-31]) at 3, 6, and 12 months. The primary efficacy outcome was the percentage of SF reduction compared to the reference period and CG at 3 months. Secondary outcomes were SF and bilateral tonic-clonic seizure (BTCS) reduction, scale score changes, and correlations with 25(OH)D during the follow-up. RESULTS: Eighty-eight patients were enrolled in the study (56 females, aged 17-74 years), with median baseline SF per 3 months = 16.5 and ≥2 antiseizure medications in 88.6%. In 75 patients (85%), 25(OH)D was <30 ng/mL; 40 of them were randomly assigned to EG and 34 to CG. After the 3-month blinded period, SF reduction did not significantly differ between groups. However, during the open-label period, SF significantly decreased (30% median SF reduction, 33% responder rate at 12 months). BTCSs were reduced by 52%. M-FIS and QOLIE-31 scores were significantly improved at the whole group level. SF reduction correlated with 25(OH)D > 30 ng/mL for >6 months. SIGNIFICANCE: Despite no proven effect after the 3-month blinded period, the open-label study suggests that long-term vitamin D3 supplementation with optimal 25(OH)D may reduce SF and BTCSs, with a positive effect on fatigue and quality of life. These findings need to be confirmed by further long-term studies. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03475225 (03-22-2018).

Exploring the link between vitamin D deficiency and obstructive sleep apnea: A comprehensive review.

Despite the high prevalence and significant health burden of obstructive sleep apnea (OSA), its underlying pathophysiology remains incompletely understood. This comprehensive review explores the emerging connection between vitamin D deficiency and OSA, discusses potential mechanisms underlying this association, and explores the therapeutic implications of these findings. Recent research has consistently highlighted the high incidence of vitamin D deficiency among patients with OSA, which often occurs independently of geographical location. This suggests that factors beyond lack of sunlight exposure may be involved. This review also discusses how reduced vitamin D may be associated with more severe manifestations of OSA. In addition, it explores the potentiality of using vitamin D supplements as a therapeutic strategy for OSA, noting that some studies have found improvements in sleep quality and a reduction in OSA severity. Potential mechanisms are proposed, including the role of vitamin D deficiency in promoting inflammation, oxidative stress, hypoxia, impairing immune function, muscle function, and gene polymorphism of vitamin D receptors, all of which could contribute to the pathogenesis of obstructive sleep apnea. The paper underscores the need for future research to validate these observations, to determine optimal vitamin D supplementation dosage and duration, to explore potential side effects and risks, and to investigate potential interactions with other treatments.

Histomorphometric analysis of patients with femoral neck fracture and 25-hydroxyvitamin D deficiency: a cross-sectional study.

INTRODUCTION: Vitamin D deficiency causes osteoporosis, bone mineralization disorders, and osteomalacia. Osteomalacia is diagnosed using blood biochemical tests, clinical symptoms, and imaging; however, accurate detection of mineralization disorders requires tissue observation. We investigated the prevalence of bone mineralization disorders and their relationship with serum 25-hydroxyvitamin D (25OHD) levels in patients with untreated osteoporosis with femoral neck fractures. MATERIALS AND METHODS: A non-demineralized specimen was prepared from the femoral head removed during surgery in 65 patients. Bone histomorphometry of cancerous bone in the femoral head center was conducted. Osteoid volume per bone volume (OV/BV) and osteoid thickness (O.Th) were measured as indicators of mineralization disorder. RESULTS: The mean serum 25OHD level (11.9 ± 5.7 ng/mL) was in the deficiency range (< 12 ng/mL). There were no clinically diagnosed cases of osteomalacia (OV/BV > 10% and O.Th > 12.5 µm); however, one case of mineralization disorder, considered histologically pre-osteomalacia (OV/BV > 5% and O.Th < 12.5 µm), was observed (OB/BV, 17.6%; O.Th, 12.3 µm). Excluding this case, those with severe (25OHD < 12 ng/mL, at risk of osteomalacia; n = 39) and non-severe deficiency (25OHD ≥ 12 ng/mL; n = 25) did not significantly differ in OV/BV (%; 0.77 ± 0.54 vs. 0.69 ± 0.38, p = 0.484) or O.Th (µm; 5.32 ± 1.04 vs. 5.13 ± 0.78, p = 0.410). Further, 25OHD and OV/BV were not significantly correlated (R = - 0.124, p = 0.327). CONCLUSION: This is the first study in the twenty-first century to examine serum 25OHD concentrations and bone mineralization disorders in Japanese patients with osteoporosis. The results indicate that vitamin D deficiency does not necessarily cause bone mineralization disorders and rarely leads to osteomalacia.

Comparative efficacies of vitamin D supplementation regimens in infants: a systematic review and network meta-analysis.

Vitamin D deficiency in infants is widely prevalent. Most paediatric professional associations recommend routine vitamin D prophylaxis for infants. However, the optimal dose and duration of supplementation are still debated. We aimed to compare the efficacy and safety of different vitamin D supplementation regimens in term and late preterm neonates. For this systematic review and network meta-analysis, we searched MEDLINE, the Cochrane Central Register of Controlled Trials and Embase. Randomised and quasi-randomised clinical trials that evaluated any enteral vitamin D supplementation regimen initiated within 6 weeks of life were included. Two researchers independently extracted data on study characteristics and outcomes and assessed quality of included studies. A network meta-analysis with a Bayesian random-effects model was used for data synthesis. Certainty of evidence (CoE) was assessed using GRADE. Primary outcomes were mean serum vitamin D concentrations and the proportion of infants with vitamin D insufficiency (VDI). We included twenty-nine trials that evaluated fourteen different regimens of vitamin D supplementation. While all dosage regimens of ≥400 IU/d increased the mean 25(OH)D levels compared with no treatment, supplementation of ≤250 IU/d and 1400 IU/week did not. The CoE varied from very low to high. Low CoE indicated that 1600 IU/d, compared with lower dosages, reduced the proportion of infants with VDI. However, our results indicated that any dosage of ≥800 IU/d increased the risk of hypervitaminosis D and hypercalcaemia. Data on major clinical outcomes were sparse. Vitamin D supplementation of 400-600 IU/d may be the most effective and safest in infants.

Prevalence of vitamin D deficiency and the effect of vitamin D3 supplementation on response to anti-tuberculosis therapy in patients with extrapulmonary tuberculosis.

BACKGROUND: We aimed to assess serum 25-hydroxyvitamin D3 (25(OH)D3) concentrations in extrapulmonary tuberculosis (EPTB) patients and to evaluate the effect of vitamin D3 supplementation on their treatment course. METHODS: Serum 25(OH)D3concentrations were measured in 47 newly diagnosed EPTB patients and 42 controls. Vitamin D-deficient EPTB patients were randomly assigned to receive 50,000 IU of vitamin D3 (cholecalciferol) orally once a week for 6 weeks (total 300,000 IU), followed by maintenance doses of 1000 IU a day besides anti-TB drugs or the first line anti-TB treatment only. Follow up serum 25(OH)D3 concentrations were measured after 3 months of starting vitamin D3 supplementation. Both groups were evaluated for clinical, laboratory, and radiological outcomes after treatment. RESULTS: Serum 25(OH)D3 concentrations were significantly lower among TB cases (17.1 ± 5.5 nmol/L) compared to healthy controls (51.8 ± 27.3 nmol/L), and vitamin D deficiency was observed in all EPTB patients (n = 47). Patients in VD3 supplementation group had significantly higher weight gain and serum albumin level at 2 months and end of treatment, higher hemoglobin concentration at the end of treatment, significantly lower CRP and ESR at 2 months and at the end of treatment. In cases with TB pleurisy, a significant higher rate of full resolution of pleural fluid after 6 months of anti-TB treatment and shorter treatment duration were noted compared to the other group. CONCLUSIONS: Vitamin D deficiency is prevalent in EPTB patients, in whom, vitamin D supplementation is a useful adjunctive therapy to anti-TB drugs and improves treatment course.

Relationship between urinary tract infections and serum vitamin D level in adults and children- a literature review.

Over time, researchers have accumulated significant evidence indicating that vitamin D deficiency not only impacts skeletal health but also contributes to the development and progression of various diseases, including cancer, diabetes, and cardiovascular conditions. The risk of low serum 1, 25(OH)2D3 level ultimately directs the way to morbidity, the beginning of new diseases, and numerous infections. Infections are the first entity that affects those with vitamin D deficiency. The common infection is urinary tract infection (UTI), and its relationship with vitamin D deficiency or insufficiency remains controversial. This infection affects both men and women, but comparatively, women are more prone to this infection because of the short length of the urethra, which makes an easy entry for the bacteria. The low level of serum vitamin D increases the risk of UTIs in children. Recurrent UTIs are one of the major weaknesses in women; if left untreated, they progress to appallingly serious conditions like kidney dysfunction, liver damage, etc. Hence improving the vitamin D status may help to improve the immune system, thus making it more resistant to infections. In this review, we have focused on examining whether vitamin D deficiency and insufficiency are the causes of UTIs and the association between them in women and children. We have also described the connection between vitamin D deficiency and insufficiency with UTIs and additional nanotechnology- based treatment strategies.

Vitamin D Levels as a Potential Modifier of Eosinophilic Esophagitis Severity in Adults.

BACKGROUND: Vitamin D deficiency is associated with atopic and immune-mediated diseases but has not been extensively assessed in eosinophilic esophagitis (EoE). We aimed to assess if vitamin D levels in newly diagnosed EoE patients were lower than in non-EoE controls and examine levels in relation to EoE clinical features. METHODS: This secondary analysis of a prospective cohort study used data and biosamples from adults who underwent outpatient esophagogastroduodenoscopy. Before each procedure, blood was obtained and stored at -80oC. Serum 25-hydroxy-vitamin D3 (25(OH)D3) was measured by ELISA. Levels for cases and controls were compared at baseline. Within cases, 25(OH)D3 levels were compared for clinical, endoscopic, and histologic measures. RESULTS: We analyzed 40 EoE and 40 non-EoE controls. Mean serum 25(OH)D3 level was slightly lower in EoE patients than controls (30.9 ± 15.3 ng/mL vs. 35.9 ± 15.4; p = 0.15). After controlling for age, sex, and race, adjusted levels were 10.8 ng/mL lower in EoE patients (95% CI: -19.0, -2.5), but 25(OH)D3 deficiency (< 20ng/mL) was similar in cases and controls (20% vs. 15%; p = 0.56). Levels of 25(OH)D3 were not associated with differences in clinical or endoscopic features of EoE, and EREFS and eosinophil counts did not significantly correlate with 25(OH)D3 levels (R of -0.28 [p = 0.08] and - 0.01 [p = 0.93], respectively). 25(OH)D3 levels were lower in EoE cases with lamina propria fibrosis (23.2 ± 9.6 vs. 45.0 ± 17.7; p = 0.03). CONCLUSIONS: After adjusting for age, sex, and race, 25(OH)D3 levels were lower in EoE cases than controls, but deficiency was not common. 25(OH)D3 levels were generally similar across most EoE disease features.

Low Vitamin D Levels in Patients with Symptoms of Gastroparesis: Relationships with Nausea and Vomiting, Gastric Emptying and Gastric Myoelectrical Activity.

Patients with gastroparesis (Gp) often have diets deficient in calories, electrolytes, and vitamins. Vitamin D levels have been reported to be low in some patients with Gp but has not been systematically studied. AIMS: To determine vitamin D levels and relationships among symptoms, gastric emptying and gastric myoelectrical activity (GMA) in patients with symptoms of Gp. METHODS: 25-hydroxy-vitamin D was measured in patients at enrollment in the Gastroparesis Clinical Consortium Registry. Gastroparesis Cardinal Symptoms Index (GCSI), gastric emptying, and GMA before and after water load satiety test (WLST) were measured. GMA, expressed as percentage distribution of activity in normal and dysrhythmic ranges, was recorded using electrogastrography. RESULTS: Overall, vitamin D levels were low (< 30 ng/ml) in 288 of 513 (56.1%) patients with symptoms of Gp (206 of 376 (54.8%) patients with delayed gastric emptying (Gp) and 82 of 137 (59.9%) patients with symptoms of Gp and normal gastric emptying). Low vitamin D levels were associated with increased nausea and vomiting (P < 0.0001), but not with fullness or bloating subscores. Low vitamin D levels in patients with Gp were associated with greater meal retention at four hours (36% retention) compared with Gp patients with normal vitamin D levels (31% retention; P = 0.05). Low vitamin D in patients with normal gastric emptying was associated with decreased normal 3 cpm GMA before (P = 0.001) and increased tachygastria after WLST (P = 0.01). CONCLUSIONS: Low vitamin D levels are present in half the patients with symptoms of gastroparesis and are associated with nausea and vomiting and gastric neuromuscular dysfunction.

Persistence of vitamin D deficiency among Italian patients with acute myocardial infarction.

BACKGROUND AND AIMS: Vitamin D deficiency is a common cardiovascular risk factor associated with the development of atherosclerosis. We evaluated changes in 25(OH)D concentrations in 1510 patients with acute myocardial infarction (AMI) over a long observation period, including the COVID-19 pandemic. METHODS AND RESULTS: Patients were separated into four groups according to the year of enrolment, group 1 (2009-2010), group 2 (2014-2016), group 3 (2017-2019), and group 4 (2020-2022). The median 25(OH)D concentration in the overall cohort was 17.15 (10.3-24.7) ng/mL. The median plasma concentrations of 25(OH)D for groups 1, 2, 3, and 4 were 14.45 (7.73-22.58) ng/mL, 17.3 ng/mL (10.33-24.2), 18.95 (11.6-26.73) ng/mL and 19.05 (12.5-27.3) ng/mL, respectively. Although 25(OH)D levels increased over the years, the prevalence of vitamin D deficiency remained high in each group (68.4%, 61.4%, 53.8%, and 52% respectively). Hypovitaminosis D was predicted by the season influence (OR:2.03, p < 0.0001), higher body mass index (OR:1.25; p = 0.001), diabetes mellitus (OR:1.54; p = 0.001), smoking (OR:1.47; p = 0.001), older age (OR:1.07; p = 0.008), higher triglycerides levels (OR:1.02; p = 0.01), and female gender (OR:1.3; p = 0.038). After multivariable adjustment, vitamin D ≤ 20 ng/mL was an independent predictor of mortality. CONCLUSION: Vitamin D deficiency is highly prevalent and persistent in patients with AMI despite a trend towards increasing 25(OH)D concentrations over the years. The frequent lockdowns did not reduce the levels of 25(OH)D in the fourth group. Low levels of 25(OH)D are an independent predictor of mortality.

Dental caries in children and vitamin D deficiency: a narrative review.

Dental caries represents one of the most prevalent health problems in childhood. Numerous studies have assessed that vitamin D deficiency is highly related to dental caries in primary and permanent teeth in children. The aim of this study is to elaborate a narrative review about proposed mechanisms by which vitamin D deficiency interacts with dental caries process in children. Vitamin D deficiency during pregnancy may cause intrauterine enamel defects, and through childhood is accompanied by insufficient activity of antibacterial peptides, decreased saliva secretion, and a low level of calcium in saliva.  Conclusion: In conclusion, vitamin D deficiency would increase the risk of caries in the primary and/or permanent dentition. Relationship between vitamin D deficiency and dental caries is evident enough for vitamin D deficiency to be considered as a risk factor for dental caries in children. Optimal levels of vitamin D throughout pregnancy and childhood may be considered an additional preventive measure for dental caries in the primary and permanent dentition.

Prevalence and risk factors of low vitamin D levels in children and adolescents with familial hypokalemic periodic paralysis.

Patients with familial hypokalemic periodic paralysis (HOKPP) experience episodes of reversible immobility and are at an increased risk of limited sunlight exposure, potentially leading to vitamin D deficiency. However, there is a lack of data on vitamin D levels in this population. We investigated serum vitamin D levels and their associated factors in children with HOKPP. This study included 170 genetically-confirmed children with HOKPP, aged 3-18 years, and 170 age-, sex-, and body mass index (BMI)-matched healthy controls from the Korean Channelopathy Study, a prospective controlled investigation. Anthropometric and clinical characteristics were recorded, and serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D, and intact parathyroid hormone (PTH) were analyzed. Vitamin D deficiency (< 20 ng/mL) was observed in 87.0% of the patients compared to 45.5% of the controls (P < 0.05) during the summer-fall season. During the winter-spring season, 91.7% of the patients and 73.4% of the controls were deficient (P < 0.05). A strong positive correlation was found between onset age of the first paralytic attack and vitamin D levels (r = 0.78, P < 0.01). Conversely, the frequency and duration of paralytic attacks were negatively correlated with vitamin D levels (r = -0.82 and r = -0.65, P < 0.01, respectively). Age, BMI, age at onset, frequency and duration of attacks, and PTH levels were independently associated with vitamin D levels (ß = -0.10, -0.12, 0.19, -0.27, -0.21, and -0.13, P < 0.05, respectively). CONCLUSIONS: Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics. We recommend routine screening for vitamin D levels in these patients to address this prevalent deficiency. Considering the high prevalence of vitamin D deficiency observed, further research on other diseases characterized by reversible immobility is warranted. WHAT IS KNOWN: • A correlation between immobility and low serum vitamin D levels has been established. However, the vitamin D status of patients with familial hypokalemic periodic paralysis (HOKPP) who experience periods of reversible immobility remains unknown. WHAT IS NEW: • Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics.

The association between maternal vitamin D deficiency and postpartum hemorrhage and uterine atony.

INTRODUCTION: Postpartum hemorrhage is the leading cause of maternal morbidity and mortality worldwide. There are several known risk factors for postpartum hemorrhage related to pregnancy and delivery, but less evidence of predisposing factors. Recent research has shown that vitamin D deficiency may increase the risk of cesarean section due to dystocia, based on its effect on striated muscle as well as possible effect on the myometrium. Whether vitamin D deficiency increases the risk for postpartum hemorrhage and especially atonic hemorrhage is unknown. MATERIAL AND METHODS: This was a retrospective translational study. The study population included 1367 women in Sweden and the main exposure was the serum concentration of 25-hydroxylated vitamin D at time of delivery. The LIASON® 25 OH vitamin D total assay method was used for analyzing 25-hydroxylated vitamin D. Vitamin D insufficiency was defined as serum concentration <50 nmol/L and vitamin D deficiency as serum concentrations <25 nmol/L. Primary outcomes were postpartum hemorrhage and severe postpartum hemorrhage defined as bleeding ≥500 mL and ≥ 1000 mL, respectively 2 h after delivery. Secondary outcome was atonic postpartum hemorrhage. Crude and adjusted odds ratios were calculated with 95% confidence intervals using univariable and multivariable logistic regression. Three different adjustment methods were used, adjusting for maternal, obstetrical and neonatal confounders. RESULTS: Postpartum hemorrhage and severe postpartum hemorrhage afflicted 31.3% and 6.4% of the women, respectively. Rate of atonic postpartum hemorrhage was 21% in the whole population. Rate of vitamin D insufficiency and deficiency was 57%. Vitamin D insufficiency or deficiency was neither found to be associated with postpartum hemorrhage, nor with atonic postpartum hemorrhage. CONCLUSIONS: In this study, the vitamin D status of women at the time of delivery was not a predictor of postpartum hemorrhage overall or atonic postpartum hemorrhage.

Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic review and meta-analysis.

Prenatal vitamin D (PVD) is a vital micronutrient for dental caries (DCs). The association between prenatal vitamin D deficiencies (PVDD) and DCs in children has been conflicting in different reports. This meta-analysis aimed to investigate the association between PVDD and DCs in children for the first time. We searched PubMed, Scopus, Web of Sciences, Embase, and Scholar databases to find relevant studies based on mesh terms from 2000 to October 2023. This study was conducted based on the 2020 version of the PRISMA checklist. Cochran's Q and I2 tests were used to evaluate heterogeneity between studies. Egger's test was used to evaluate publication bias. The effect size of the association between PVDD and DCs was reported by the odds ratio (OR) at the 95% confidence interval (95% CI).Twelve studies, including 11,021 participants, were reviewed. The pooled prevalence of PVDD was estimated at 4353 (32%). The prevalence of DCs in children of mothers with and without PVDD was 44% and 25%, respectively. PVDD was significantly associated with an increased risk of DCs in children (OR: 1.35, 95% CI (1.22, 1.47), I2 = 86.6%). The association of DCs with PVDD was different based on gestational age groups, children's age groups, and vitamin D levels. This meta-analysis showed PVDD can be associated with an increased risk of DCs in children, especially in mothers with prenatal vitamin D levels ≤ 35 nmol/L. Adequate vitamin D levels throughout pregnancy can help prevent DCs in children.

Analysis of pupillary responses in pediatric patients with vitamin D deficiency.

PURPOSE: To evaluate the effects of vitamin D deficiency on pupillary responses in the pediatric population. METHODS: The study was conducted using data from the right eyes of 52 children with vitamin D deficiency and 52 healthy children. Measurements were taken under static and dynamic conditions with automatic pupillometry. Static measurements were performed at scotopic, mesopic, and photopic light intensities. The mean pupil dilation speed was calculated by observing the changes in pupil dilation over time according to dynamic measurements. Differences between patient and control groups were analyzed for the static and dynamic measurements and the mean pupil dilation speed. RESULTS: While the two groups were similar in terms of scotopic, mesopic, the first dynamic measurements, and the pupil dilation speed data (p > 0.05), a significant difference was found in the photopic conditions (p = 0.001). The mean pupil diameter of the patient group was 4.46 ± 0.928 mm and 3.95 ± 0.556 mm in the control group under photopic conditions. CONCLUSIONS: Pediatric patients with vitamin D deficiency have significantly larger pupil diameters in photopic conditions than healthy children. These results suggest that there is an autonomic dysfunction in vitamin D deficiency in the pediatric population, especially pointing to the parasympathetic system.