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Open access

Zhen-yu Song, Qiuming Yao, Zhiyuan Zhuo, Zhe Ma, and Gang Chen

Previous studies investigating the association of circulating 25-hydroxyvitamin D level with prognosis of prostate cancer yielded controversial results. We conducted a dose–response meta-analysis to elucidate the relationship. PubMed and EMBASE were searched for eligible studies up to July 15, 2018. We performed a dose–response meta-analysis using random-effect model to calculate the summary hazard ratio (HR) and 95% CI of mortality in patients with prostate cancer. Seven eligible cohort studies with 7808 participants were included. The results indicated that higher vitamin D level could reduce the risk of death among prostate cancer patients. The summary HR of prostate cancer-specific mortality correlated with an increment of every 20 nmol/L in circulating vitamin D level was 0.91, with 95% CI 0.87–0.97, P = 0.002. The HR for all-cause mortality with the increase of 20 nmol/L vitamin D was 0.91 (95% CI: 0.84–0.98, P = 0.01). Sensitivity analysis suggested the pooled HRs were stable and not obviously changed by any single study. No evidence of publications bias was observed. This meta-analysis suggested that higher 25-hydroxyvitamin D level was associated with a reduction of mortality in prostate cancer patients and vitamin D is an important protective factor in the progression and prognosis of prostate cancer.

Open access

Malachi J McKenna, Barbara F Murray, Myra O'Keane, and Mark T Kilbane

Background

The Institute of Medicine 2011 Report on Dietary Reference Intakes for Calcium and Vitamin D specified higher intakes for all age groups compared to the 1997 report, but also cautioned against spurious claims about an epidemic of vitamin D deficiency and against advocates of higher intake requirements. Over 40 years, we have noted marked improvement in vitamin D status but we are concerned about hypervitaminosis D.

Objective

We sought to evaluate the 25-hydroxyvitamin D (25OHD) trend over 20 years.

Design

We retrieved all results of serum 25OHD from 1993 to 2013 (n=69 012) that was trimmed to one sample per person (n=43 782). We conducted a time series analysis of the monthly averages for 25OHD using a simple sequence chart and a running median smoothing function. We modelled the data using univariate auto-regressive integrated moving average (ARIMA) and forecast 25OHD levels up to 2016.

Results

The time series sequence chart and smoother function demonstrated a steady upward trend with seasonality. The yearly average 25OHD increased from 36.1 nmol/l in 1993 to 57.3 nmol/l in 2013. The ARIMA model was a good fit for the 25OHD time series; it forecasted monthly average 25OHD up to the end of 2016 with a positive stationary R 2 of 0.377.

Conclusions

Vitamin D status improved over the past 40 years, but there remains a dual problem: there are groups at risk of vitamin D deficiency who need public health preventative measures; on the other hand, random members of the population are taking unnecessarily high vitamin D intakes for unsubstantiated claims.

Open access

Maria Luisa Brandi, Stefania Bandinelli, Teresa Iantomasi, Francesca Giusti, Eleonora Talluri, Giovanna Sini, Fabrizio Nannipieri, Santina Battaglia, Riccardo Giusti, Colin Gerard Egan, and Luigi Ferrucci

Objective

This study aimed to evaluate the association between the endocrine-disrupting chemical, bisphenol A (BPA) on circulating levels of 25-hydroxy vitamin D (25(OD)D) and other vitamin D metabolites in an elderly population in Italy.

Methods

This was a retrospective analysis of the InCHIANTI Biobank in Italy. The association between vitamin D metabolites namely 1,25(OH)D, 25(OH)D, parathyroid hormone (PTH) and BPA levels were evaluated. Multiple regression models were used to examine the association between predictor variables with 1,25(OH)D or 25(OH)D levels.

Results

Samples from 299 individuals aged 72.8 ± 15.7 years were examined. Mean levels of BPA, 1,25(OH)D and 25(OH)D were 351.2 ± 511.6 ng/dL, 43.7 ± 16.9 pg/mL and 20.2 ± 12.1 ng/mL, respectively. One hundred eighty individuals (60.2%) were deficient (<20 ng/mL) in 25(OH)D and this population also presented higher BPA levels (527.9 ± 1289.5 ng/dL vs 86.9 ± 116.8 ng/dL, P  < 0.0001). Univariate analysis revealed that BPA levels were negatively correlated with both 1,25(OH)D (r= −0.67, P  < 0.0001) and 25(OH)D (r= −0.69, P  < 0.0001). Multivariate regression revealed that PTH (β: −0.23, 95% CI: −0.34, −0.13, P  < 0.0001) and BPA (β: −0.25, 95% CI: −0.3, −0.19, P  < 0.0001) remained significantly associated with 25(OH)D levels while BPA was also associated with 1,25(OH)D levels (β: −0.19, 95% CI: −0.22, −0.15, P  < 0.0001). Receiver operating characteristic curve analysis showed that a BPA concentration of >113 ng/dL was the best cut-off to predict individuals deficient in 25(OH)D (area under the curve: 0.87, 95% CI: 0.82–0.90, P  < 0.0001).

Conclusion

The strong negative association between BPA and vitamin D in this elderly population warrants further investigation, particularly since this population is already at greatest risk of hypovitaminosis and fracture.

Open access

Eliana Piantanida, Daniela Gallo, Giovanni Veronesi, Eugenia Dozio, Eugenia Trotti, Adriana Lai, Silvia Ippolito, Jessica Sabatino, Maria Laura Tanda, Antonio Toniolo, Marco Ferrario, and Luigi Bartalena

Objective

The aim of this observational study was to clarify the link between vitamin D status and metabolic syndrome (MetS) in people with visceral obesity.

Design and methods

One hundred ninety-six consecutive patients (152 women; mean age 51 ± 13 years) with visceral obesity (mean body weight 103 ± 20 kg, mean waist circumference (WC) 119 ± 13 cm) were enrolled at the Obesity Outpatient Clinic of the University of Insubria in Varese. Anthropometric measurements were recorded. Laboratory tests, including vitamin D (25(OH)D)), fasting blood glucose (FBG), lipid profile, liver and kidney function tests were assessed. Vitamin D status was defined according to the European Society of Endocrinology guidelines, MetS to the 2009 harmonized definition.

Results

An inverse association emerged among 25(OH)D, body mass index (BMI) (P = 0.001) and WC (all P = 0.003). Serum 25(OH)D levels were inversely related to FBG and systolic blood pressure (SBP) (respectively, P = 0.01 and 0.02). Median serum 25(OH)D levels were 13.3 ng/mL (CI 95% 12; 15) in MetS and 16 ng/mL (CI 95% 14; 18) (P = 0.01) in non-MetS patients. Among patients with MetS, lower 25(OH)D concentrations were related to higher risk of hypertension (HT) (odds ratio (OR) 1.7, CI 95%, 0.7;4) and hyperglycemia (IFG)/type 2 diabetes (OR 5.5, CI 95% 2; 14).

Conclusion

Vitamin D status and MetS are inversely correlated in visceral obesity, particularly with regard to glucose homeostasis and BP. More extensive studies are required to investigate the potential for causality.

Open access

Silvia Ciancia, Vanessa Dubois, and Martine Cools

Both in the United States and Europe, the number of minors who present at transgender healthcare services before the onset of puberty is rapidly expanding. Many of those who will have persistent gender dysphoria at the onset of puberty will pursue long-term puberty suppression before reaching the appropriate age to start using gender-affirming hormones. Exposure to pubertal sex steroids is thus significantly deferred in these individuals. Puberty is a critical period for bone development: increasing concentrations of estrogens and androgens (directly or after aromatization to estrogens) promote progressive bone growth and mineralization and induce sexually dimorphic skeletal changes. As a consequence, safety concerns regarding bone development and increased future fracture risk in transgender youth have been raised. We here review published data on bone development in transgender adolescents, focusing in particular on differences in age and pubertal stage at the start of puberty suppression, chosen strategy to block puberty progression, duration of puberty suppression, and the timing of re-evaluation after estradiol or testosterone administration. Results consistently indicate a negative impact of long-term puberty suppression on bone mineral density, especially at the lumbar spine, which is only partially restored after sex steroid administration. Trans girls are more vulnerable than trans boys for compromised bone health. Behavioral health measures that can promote bone mineralization, such as weight-bearing exercise and calcium and vitamin D supplementation, are strongly recommended in transgender youth, during the phase of puberty suppression and thereafter.

Open access

Marc Blondon, Emmanuel Biver, Olivia Braillard, Marc Righini, Pierre Fontana, and Alessandro Casini

Objective

Vitamin D deficiency is associated with increased risks of arterial and venous cardiovascular events. Hypothetically, supplementation with vitamin D may lead to a less prothrombotic phenotype, as measured by global coagulation assays and fibrin clot structure.

Methods

In this prospective cohort study, we enrolled adult outpatients attending the Primary Care Division of the Geneva University Hospitals with a severe vitamin D deficiency (25-hydroxyvitamin-D3 (25-OHD) <25 nmol/L), excluding obese patients or with a recent acute medical event. We evaluated changes in coagulation times, thrombin generation assay, clot formation and clot lysis time, 25-OHD and parathormone before and 1–3 months after cholecalciferol oral supplementation with one-time 300,000 IU then 800 IU daily. Paired t-tests with a two-sided alpha of 0.05 compared absolute mean differences.

Results

The 48 participants had a mean age of 43.8 ± 13.8 years. After supplementation, 25-OHD levels increased from 17.9 ± 4.6 nmol/L to 62.5 ± 20.7 nmol/L 6.4 ± 3.0 weeks after inclusion. Endogenous thrombin potential and thrombin generation peak values both decreased significantly (−95.4 nM × min (95%CI −127.9 to −62.8), P < 0.001; −15.1 nM (−23.3 to −6.8), P < 0.001). The maximum absorbance by turbidimetry decreased significantly (P = 0.001) after supplementation. There was no change in clot lysis time, coagulation times or plasminogen activator inhibitor-1 and homocysteine levels.

Conclusions

In severe vitamin D deficiency, a high-dose cholecalciferol supplementation was associated with a reduction in thrombin generation and an average decreased number of fibrin protofibrils per fibers and fibrin fiber size measured by turbidimetry. This suggests that severe vitamin D deficiency may be associated with a potentially reversible prothrombotic profile.

Open access

Giuseppe Grande, Andrea Graziani, Antonella Di Mambro, Riccardo Selice, and Alberto Ferlin

Low bone mass is common in men with Klinefelter syndrome (KS), with a prevalence of 6-15% of osteoporosis and of 25-48% of osteopenia. Reduced bone mass has been described since adolescence and it might be related to both reduced bone formation and higher bone resorption. Although reduced testosterone levels are clearly involved in the pathogenesis, this relation is not always evident. Importantly, fracture risk is increased independently from bone mineral density (BMD) and testosterone levels. Here we discuss the pathogenesis of osteoporosis in patients with KS, with a particular focus on the role of testosterone and testis function. In fact, other hormonal mechanisms, such as global Leydig cell dysfunction, causing reduced Insulin-like factor 3 (INSL3) and 25-OH vitamin D levels, and high FSH and estradiol levels, might be involved. Furthermore, genetic aspects related to the supernumerary X chromosome might be involved, as well as androgen receptor expression and function. Notably, body composition, skeletal mass and strength, and age at diagnosis are other important aspects. Although Dual-Energy X-ray Absorptiometry (DXA) is recommended in the clinical workflow for patients with KS to measure BMD, recent evidence suggests that alterations in the microarchitecture of the bones and vertebral fractures might be present even in subjects with normal BMD. Therefore, analysis of trabecular bone score (TBS), high resolution peripheral quantitative CT and vertebral morphometry seem promising tools to better estimate the fracture risk of patents with KS. This review also summarizes the evidence on the best available treatments for osteoporosis in men with KS, with or without hypogonadism.

Open access

R Perchard, L Magee, A Whatmore, F Ivison, P Murray, A Stevens, M Z Mughal, S Ehtisham, J Campbell, S Ainsworth, M Marshall, M Bone, I Doughty, and P E Clayton

Background

Higher 25(OH)D3 levels are associated with lower HbA1c, but there are limited UK interventional trials assessing the effect of cholecalciferol on HbA1c.

Aims

(1) To assess the baseline 25(OH)D3 status in a Manchester cohort of children with type 1 diabetes (T1D). (2) To determine the effect of cholecalciferol administration on HbA1c.

Methods

Children with T1D attending routine clinic appointments over three months in late winter/early spring had blood samples taken with consent. Participants with a 25(OH)D3 level <50 nmol/L were treated with a one-off cholecalciferol dose of 100,000 (2–10 years) or 160,000 (>10 years) units. HbA1c levels before and after treatment were recorded.

Results

Vitamin D levels were obtained from 51 children. 35 were Caucasian, 11 South Asian and 5 from other ethnic groups. 42 were vitamin D deficient, but 2 were excluded from the analysis. All South Asian children were vitamin D deficient, with mean 25(OH)D3 of 28 nmol/L. In Caucasians, there was a negative relationship between baseline 25(OH)D3 level and HbA1c (r = −0.484, P < 0.01). In treated participants, there was no significant difference in mean HbA1c at 3 months (t = 1.010, P = 0.328) or at 1 year (t = −1.173, P = 0.248) before and after treatment. One-way ANCOVA, controlling for age, gender, ethnicity, BMI and diabetes duration showed no difference in Δ HbA1c level.

Conclusion

We report important findings at baseline, but in children treated with a stat dose of cholecalciferol, there was no effect on HbA1c. Further studies with larger sample sizes and using maintenance therapy are required.

Open access

Jean-Philippe Bertocchio, Natalie Grosset, Lionel Groussin, Peter Kamenický, Fabrice Larceneux, Anne Lienhardt-Roussie, Agnès Linglart, Gérard Maruani, Eric Mirallie, François Pattou, Riyad N H Seervai, Coralie Sido, Caroline Silve, Aurélie Vilfaillot, Antoine Tabarin, Marie-Christine Vantyghem, Pascal Houillier, and the investigators of the Épi-Hypo study

Context

Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians’ practices or their adherence to such guidelines.

Objective

To describe the physicians’ practice patterns and their compliance with international guidelines.

Design

The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019).

Methods

Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients).

Results

The physicians’ specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion.

Conclusions

The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.

Open access

Sarah Bakhamis, Faiqa Imtiaz, Khushnooda Ramzan, Edward De Vol, Osamah Al-Sagheir, Abdulrahman Al-Rajhi, Abdullah Alashwal, Bassam Bin Abbas, Nadia Sakati, and Afaf Al-Sagheir

Vitamin D deficiency remains a major cause of rickets worldwide. Nutritional factors are the major cause and less commonly, inheritance causes. Recently, CYP2R1 has been reported as a major factor for 25-hydroxylation contributing to the inherited forms of vitamin D deficiency. We conducted a prospective cohort study at King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia, to review cases with 25-hydroxylase deficiency and describe their clinical, biochemical, and molecular genetic features. We analyzed 27 patients from nine different families who presented with low 25-OH vitamin D and not responding to usual treatment. Genetic testing identified two mutations: c.367+1G>A (12/27 patients) and c.768dupT (15/27 patients), where 18 patients were homozygous for their identified mutation and 9 patients were heterozygous. Both groups had similar clinical manifestations ranging in severity, but none of the patients with the heterozygous mutation had hypocalcemic manifestations. Thirteen out of 18 homozygous patients and all the heterozygous patients responded to high doses of vitamin D treatment, but they regressed after decreasing the dose, requiring lifelong therapy. Five out of 18 homozygous patients required calcitriol to improve their biochemical data, whereas none of the heterozygous patients and patients who carried the c.367+1G>A mutation required calcitriol treatment. To date, this is the largest cohort series analyzing CYP2R1-related 25-hydroxylase deficiency worldwide, supporting its major role in 25-hydroxylation of vitamin D. It is suggested that a higher percentage of CYP2R1 mutations might be found in the Saudi population. We believe that our study will help in the diagnosis, treatment, and prevention of similar cases in the future.