Single high-dose vitamin D at birth corrects vitamin D deficiency in infants in Mexico

Abstract

This study examined the prevalence of vitamin D deficiency in mothers and infants in Tijuana, Mexico and determined the effect of a single oral dose of 50?000?IU vitamin D₃ at birth on 25-hydroxyvitamin D (25[OH]D) levels during infancy. Healthy infants were randomized to receive vitamin D₃ or placebo at birth. At birth 23% of infants were vitamin D deficient and 77% had vitamin D insufficiency (mean 25[OH]D level 18.9?ng/ml); 10% of mothers were vitamin D deficient and 61% were insufficient. Infants receiving vitamin D₃ had higher 25(OH)D levels at two months (N?=?29; 33.9 versus 24.2?ng/ml) and six months (N?=?21; 36.5 versus 27.4?ng/ml). Exclusively breastfed infants had lower 25(OH)D levels at two months (14.9 versus 33.4?ng/ml). Vitamin D deficiency is common in infants and mothers in Tijuana, Mexico. A single dose of vitamin D₃ at birth was safe and significantly increased 25(OH)D levels during infancy.     

Plasma 25-hydroxyvitamin D responses of younger and older men to three weeks of supplementation with 1800 IU/day of vitamin D.

OBJECTIVE: The objective of this study was to compare changes in plasma 25-hydroxyvitamin D (25(OH)D) levels of younger and older men after three weeks of oral vitamin D supplementation. METHODS: Nine younger men (22 to 28 years) and nine older men (65 to 73 years) with self-reported vitamin D intakes below 200 IU/d were enrolled in February and randomized to 1800 IU/d of ergocalciferol (vitamin D2, n=11) or to a control group (n=7) and followed for three weeks. Blood was collected at baseline, and after one, two and three weeks for measurement of plasma concentrations of total 25(OH)D, 25(OH)D2 and 25(OH)D3. RESULTS: In both the younger and older supplemented men, 25(OH)D2 and total 25(OH)D concentrations increased significantly during the study, whereas values of these metabolites did not change in younger or older control subjects. No group showed significant changes in 25-hydroxyvitamin D3. There was a significant interaction between age group and supplement group, suggesting that the effect of vitamin D2 supplementation on changes in 25(OH)D2 changes with age. The mean increase in 25(OH)D2 was greater in the younger supplemented men than in the older supplemented men (37+/-9 nmol/L vs. 19.5 nmol/L, p=0.027), and this accounted for their significantly greater increase in total 25(OH)D. CONCLUSION: These data are consistent with an age-related decline in the absorption, transport or liver hydroxylation of orally-consumed vitamin D.     

Body Size and Serum 25 Hydroxy Vitamin D Response to Oral Supplements in Healthy Older Adults

Background: Vitamin D insufficiency is prevalent in the northeast United States. Since vitamin D insufficiency is readily amenable to supplementation, it is important to understand what factors are associated with serum 25 hydroxy vitamin D (25(OH)D) response to vitamin D supplementation.

Objective: In this study we examined the association of serum 25(OH)D response to vitamin D supplementation with body size in a population of elderly subjects.

Methods: 257 healthy, ambulatory men and women 65 years of age or older were randomly assigned to treatment with either 700 IU/day (17.5 μg/d) of supplemental vitamin D₃ and 500 mg/day (12.5 mmol/d) of supplemental calcium, or to placebo.

Results: In multivariate regression analyses, after adjusting for baseline 25(OH)D, season, and sex, we found change in 25(OH)D to be inversely associated with baseline BMI (p = 0.01) in subjects treated with supplements for one year. Change in 25(OH)D was also negatively associated with other baseline anthropometric measurements in these subjects.

Conclusion: Our study implies that body size should be taken into account when estimating the amount of vitamin D intake needed to raise 25(OH)D to the desired level.     

Vitamin D Metabolite Ratio in Pregnant Women with Low Blood Vitamin D Concentrations Is Associated with Neonatal Anthropometric Data

Existing evidence on the correlation between maternal vitamin D concentrations and birth outcomes is conflicting. Investigation of these associations requires accurate assessment of vitamin D status, especially in individuals with low 25-hydroxyvitamin D (25(OH)D) concentrations. This study examined the correlations between birth outcomes and the maternal vitamin D metabolite ratio (VMR) 1 (defined as the ratio of 24,25(OH)₂D₃ to 25(OH)D) and VMR2 (defined as the ratio of 3-epi-25(OH)D₃ to 25(OH)D) using data from the Japan Environment and Children’s Study at Chiba Regional Center. A total of 297 mother–neonate pairs were analyzed. Using liquid chromatography–tandem mass spectrometry, we measured 25(OH)D₂, 25(OH)D₃, 24,25(OH)₂D₃, and 3-epi-25(OH)D₃ concentrations in maternal serum samples. These data were analyzed in relation to birth anthropometric data using multivariable linear regression. Of the study participants, 85.2% showed insufficient vitamin D concentrations. VMR1 was strongly correlated with 25(OH)D concentrations, whereas VMR2 showed a weak correlation. Only VMR2 was associated with all anthropometric data. VMR2 in pregnant women with low vitamin D blood concentrations is a useful marker for neonatal anthropometric data and is independent of 25(OH)D. Accurate measurement of vitamin D metabolites could help better understand the effects of vitamin D on birth outcomes.     

Vitamin D2 vs. vitamin D3: They are not one and the same

Conflicting evidence has led to uncertainty as to whether vitamin D₂ and vitamin D₃ are equally efficacious in improving vitamin D status, despite historically being considered equipotent. A systematic review and meta‐analysis completed in 2012 indicated that D₃ was more effective at raising vitamin D levels {using total 25‐hydroxyvitamin D [25(OH)D] as a marker of status} but the meta‐analysis identified high levels of heterogeneity between studies and a lack of statistically powered sample sizes to provide a conclusive answer. Thus, to meet the need for robust data, our research team conducted the largest (to date) randomised, controlled trial comparing the two forms of vitamin D. The D₂–D₃ Study was conducted in 335 healthy South Asian (n = 90) and White European women (n = 245). The study was designed to compare the respective efficacy of vitamin D₂ with vitamin D₃ at raising total 25(OH)D when added to a juice or a biscuit, at a relatively low dose of 15 μg/day for 12 weeks. Overall, the results showed that those who consumed vitamin D₃ showed an average increase in vitamin D status of 74%–75%, whereas an average increase of 33%–34% in vitamin D status was found in those who consumed vitamin D₂. Therefore, this study emphatically shows that vitamin D₃ is more than twice as effective as vitamin D₂ at raising total 25(OH)D concentrations, when given in a low dose that is both physiologically relevant and in line with public health guidance.     

Evidence of low vitamin D intakes in the Australian population points to a need for data-driven nutrition policy for improving population vitamin D status

Background

Nearly one in four Australian adults is vitamin D deficient (serum 25-hydroxyvitamin D concentrations [25(OH)D] < 50 nmol L^–1) and current vitamin D intakes in the Australian population are unknown. Internationally, vitamin D intakes are commonly below recommendations, although estimates generally rely on food composition data that do not include 25(OH)D. We aimed to estimate usual vitamin D intakes in the Australian population.

Methods

Nationally representative food consumption data were collected for Australians aged ≥ 2 years (n = 12,153) as part of the cross-sectional 2011–2013 Australian Health Survey (AHS). New analytical vitamin D food composition data for vitamin D₃, 25(OH)D₃, vitamin D₂ and 25(OH)D₂ were mapped to foods and beverages that were commonly consumed by AHS participants. Usual vitamin D intakes (µg day^–1) by sex and age group were estimated using the National Cancer Institute method.

Results

Assuming a 25(OH)D bioactivity factor of 1, mean daily intakes of vitamin D ranged between 1.84 and 3.25 µg day^–1. Compared to the estimated average requirement of 10 µg day^–1 recommended by the Institute of Medicine, more than 95% of people had inadequate vitamin D intakes. We estimated that no participant exceeded the Institute of Medicine's Upper Level of Intake (63–100 µg day^–1, depending on age group).

Conclusions

Usual vitamin D intakes in Australia are low. This evidence, paired with the high prevalence of vitamin D deficiency in Australia, suggests that data-driven nutrition policy is required to safely increase dietary intakes of vitamin D and improve vitamin D status at the population level.     

The Impact of Sample Type on Vitamin D Quantification and Clinical Classification during Pregnancy

Measurement of vitamin D status has significant use in clinical and research settings, including during pregnancy. We aimed to assess the agreement of total 25-hydroxyvitamin D (25(OH)D) concentration, and its three analytes (25-hydroxyvitamin D₃ (25(OH)D₃), 25-hydroxyvitamin D₂ (25(OH)D₂) and Epi-25-hydroxyvitamin D₃ (Epi-25(OH)D₃)), in plasma and serum samples collected during pregnancy, and to examine the proportion of women who change vitamin D status category based on sample type. Matching samples were collected from n = 114 non-fasting women between 12–25 weeks gestation in a clinical trial in Newcastle, Australia. Samples were analysed by liquid chromatography-tandem mass-spectrometry (LC-MS/MS) to quantify total 25(OH)D and its analytes and examined using Bland-Altman plots, Pearson correlation (r), intraclass correlation coefficient and Cohen’s Kappa test. Serum total 25(OH)D ranged from 33.8–169.8 nmol/L and plasma ranged from 28.6–211.2 nmol/L. There was a significant difference for total 25(OH)D based on sample type (measurement bias 7.63 nmol/L for serum vs plasma (95% Confidence Interval (CI) 5.36, 9.90, p ≤ 0.001). The mean difference between serum and plasma concentrations was statistically significant for 25(OH)D₃ (7.38 nmol/L; 95% CI 5.28, 9.48, p ≤ 0.001) and Epi-25(OH)D₃ (0.39 nmol/L; 95% CI 0.14, 0.64, p = 0.014). Of 114 participants, 28% were classified as vitamin D deficient (<50 nmol/L) or insufficient (<75 nmol/L) based on plasma sample and 36% based on serum sample. Nineteen (16.7%) participants changed vitamin D status category based on sample type. 25-hydroxyvitamin D quantification using LC-MS/MS methodology differed significantly between serum and plasma, yielding a higher value in plasma; this influenced vitamin D status based on accepted cut-points, which may have implications in clinical and research settings.     

Food fortification and biofortification as potential strategies for prevention of vitamin D deficiency

Hypovitaminosis D (vitamin D deficiency) is widespread throughout the world. The cutaneous production of vitamin D through sunlight can be limited by several factors (e.g. skin pigmentation, sunscreen usage and, increasingly, indoor lifestyle). Thus, diet has become an important strategy to increase vitamin D intake and status {blood 25‐hydroxyvitamin D [25(OH)D]}. However, there are a limited number of foods that naturally contain vitamin D, and concentrations can vary significantly between and within species. The need for vitamin D‐fortified foods (including via direct fortification and biofortification) to support the adequacy of vitamin D status is a corollary of several limitations to synthesise vitamin D from sunlight. Ergocalciferol (vitamin D₂) and cholecalciferol (vitamin D₃) can be found in some mushrooms and animal‐derived foods, respectively. Evidence has shown vitamin D₃ is more effective than vitamin D₂ at raising 25(OH)D blood concentrations. The vitamin D metabolite, 25(OH)D_3, is present in animal‐derived foods (e.g. meat, eggs and fish), and several intervention trials have shown 25(OH)D₃ to be more effective at raising blood 25(OH)D concentrations than vitamin D₃. In addition, 25(OH)D₃ supplements may prove to be preferable to vitamin D₃ for patients with certain clinical conditions. However, there is limited evidence on the effects of 25(OH)D₃‐fortified foods on human vitamin D status and health, both in the general population and patients with certain conditions, and long‐term randomised controlled trials are needed in this area.     

Vitamin D Status and Severity of Clostridium difficile Infections

Background: Clostridium difficile is the most common cause of nosocomial diarrhea, affecting up to 10% of hospitalized patients. Preliminary studies suggest an association between vitamin D status and C difficile infections (CDIs). Our goal was to investigate whether serum 25‐hydroxyvitamin D (25(OH)D) levels are associated with CDI severity. Methods: We prospectively enrolled patients diagnosed with CDI and divided them into 2 severity groups: group A (positive toxin A/B enzyme immunoassay only) and group B (positive toxin A/B enzyme immunoassay with abdominal computed tomography scan findings consistent with colitis). Serum 25(OH)D levels (25(OH)D₃, 25(OH)D₂, and total 25(OH)D) were measured on all patients after diagnosis of CDI. We performed multivariable logistic regression analyses to investigate the association between 25(OH)D levels and CDI severity, while adjusting for age, Deyo‐Charlson Comorbidity Index, recent hospitalization, and vitamin D supplementation. Results: One hundred patients were enrolled between July 2011 and February 2013. The mean (standard deviation) cohort age and Deyo‐Charlson Comorbidity Index were 62 (19) years and 4 (3), respectively; 54% of patients were male. Mean serum total 25(OH)D level was 22 (10) ng/mL. Mean 25(OH)D₃ level was significantly higher in group A (n = 71) than in group B (n = 29): 21 (1) vs 15 (2) ng/mL, respectively (P = .005). There was no observed difference in mean 25(OH)D₂ levels and total 25(OH)D levels between the 2 groups. Multivariable logistic regression analysis demonstrated an association between 25(OH)D₃ levels and CDI severity (adjusted odds ratio, 0.92; 95% confidence interval, 0.87–0.98). Conclusions: We found a significant inverse association between 25(OH)D₃ levels and CDI severity. Further studies are needed to determine whether vitamin D supplementation can improve outcomes in patients with CDI.     

Plasma 25-Hydroxyvitamin D,Hormonal Contraceptive Use,and Cardiometabolic Disease Risk in an Ethnically Diverse Population of Young Adults

Objectives: The relationship between vitamin D and cardiometabolic disease risk across ethnic groups is unclear, and it is not known whether the use of hormonal contraceptives (HCs), which affect vitamin D metabolism and are also associated with cardiometabolic disease risk, modifies this relationship. Our objectives were to determine the prevalence of vitamin D deficiency (plasma 25-hydroxyvitamin D [25(OH)D] < 30 nmol/L) to assess seasonal variation in concentrations of 25(OH)D, and to examine whether 25(OH)D is associated with cardiometabolic biomarkers across ethnic groups and across men, female HC nonusers, and female HC users in an ethnically diverse population of young adults living in Canada.

Methods: The study population consisted of Caucasian, East Asian, and South Asian individuals (n = 1384, 69% female) aged 20–29 years. Participants provided overnight fasting blood samples, from which plasma 25(OH)D and cardiometabolic biomarkers were measured. Vitamin D status distributions were compared using χ² tests, and analysis of covariance (ANCOVA) was used to examine seasonal variations in 25(OH)D, as well as the association between 25(OH)D and cardiometabolic biomarkers, across groups.

Results: Plasma 25(OH)D concentrations fluctuated seasonally among Caucasians and East Asians and across men, female HC nonusers, and female HC users, but they remained low year-round in South Asians, half of whom were vitamin D deficient. Vitamin D deficiency was associated with higher insulin, homeostasis model assessment–estimated insulin resistance (HOMA-IR), and homeostasis model assessment (HOMA)-beta among Caucasians and East Asians and among men and female HC nonusers and with higher triglycerides among men only. No biomarkers were associated with 25(OH)D among South Asians and female HC users, although nonsignificant trends were observed for higher markers of glycemic dysregulation in those who were vitamin D deficient in both groups.

Conclusions: Vitamin D deficiency varies between ethnic groups and is particularly high among South Asians, and it is associated with biomarkers of glycemic dysregulation; however, HC use among women may attenuate this association. Given the widespread use of HCs by women throughout the world, a better understanding of the extent to which these medications may modify the relationship between vitamin D and processes related to disease is warranted.     

Vitamin D Deficiency in Pregnant Ukrainian Women: Effects of Alcohol Consumption on Vitamin D Status

Objective: Heavy alcohol consumption can alter vitamin D status; however, the relationships between alcohol consumption and vitamin D concentrations in pregnant women have not been well studied. The aim of this study was to investigate the vitamin D status in a population of alcohol-exposed (N = 180) and low/unexposed control (N = 179) Ukrainian pregnant women.

Methods: Women who attended prenatal care facilities in 2 regions of Ukraine (Rivne and Khmelnytsky) for a routine prenatal visit were screened for the study. At the time of enrollment (20.4 ± 7.0 weeks of gestation), blood samples and alcohol consumption data (during a typical week around conception and the most recent 2 weeks) were collected. Vitamin D status was assessed by 25-hydroxyvitamin D [25(OH)D] concentrations.

Results: A high prevalence of suboptimal vitamin D status in pregnant Ukrainian women was observed. Overall, 50.1% and 33.4% of the women were classified as vitamin D deficient [25(OH)D < 20 ng/mL] or insufficient [25(OH)D ≥ 20 ng/mL and ≤30 ng/mL], respectively, based on 2011 Endocrine Society guidelines. Alcohol-exposed women had significantly lower 25(OH)D concentrations than low/unexposed women in Spring (p = 0.006) and Winter (p = 0.022). When vitamin D concentrations were grouped into sunny season (Summer + Fall) compared to not sunny season (Winter + Spring), there was a significant ethanol by season interaction (p = 0.0028), with alcohol-drinking women having lower circulating vitamin D compared to low/unexposed women in seasons of low sun availability.

Conclusions: These data suggest that when vitamin D concentrations are generally low (e.g., during seasons of low sun availability), alcohol consumption during pregnancy has a negative impact on vitamin D status.     

Clinical Trial of Vitamin D2 vs D3 Supplementation in Critically Ill Pediatric Burn Patients

Background: Hypovitaminosis D exists postburn. However, evidence‐based guidelines for vitamin D repletion are unknown. This investigation examined differences between D₂ and D₃ supplementation on outcome in children with burn injuries. Methods: Fifty patients with total body surface area burn of 55.7% ± 2.6% and full‐thickness injury of 40.8% ± 3.8% were enrolled, ranging in age from 0.7–18.4 years. All participants received multivitamin supplementation per standardized clinical protocol. In addition, 100 IU/kg D₂, D₃, or placebo was administered daily during hospitalization using a randomized, double‐blinded study design. Assay of total 25‐hydroxyvitamin D (D25), 1,25‐dihydroxyvitamin D (D1,25), 25‐hydroxyvitamin D₂ (25‐OH‐D₂), 25‐hydroxyvitamin D₃ (25‐OH‐D₃), and parathyroid hormone (PTH) was performed at 4 preplanned time intervals (baseline, midpoint, discharge, and 1 year postburn). Differences in vitamin D status were compared over time and at each specific study interval. Results: There were no significant differences in serum vitamin D levels between groups, but >10% of patients had low D25 at discharge, and percent deficiency worsened by the 1‐year follow up for the placebo (75%), D₂ (56%), and D₃ (25%) groups. There were no statistical differences in PTH or clinical outcomes between treatment groups, although vitamin D supplementation demonstrated nonsignificant but clinically relevant decreases in exogenous insulin requirements, sepsis, and scar formation. Conclusions: The high incidence of low serum D25 levels 1 year following serious thermal injury indicates prolonged compromise. Continued treatment with vitamin D₃ beyond the acute phase postburn is recommended to counteract the trajectory of abnormal serum levels and associated morbidity.     

Association of Dietary Vitamin D Intake,Serum 25(OH)D3, 25(OH)D2 with Cognitive Performance in the Elderly

Background: As life expectancy increases, cognitive performance decline in the elderly has become one of the major global challenges. We aimed to evaluate the association of dietary vitamin D (VD), serum 25-hydroxyvitamin D3 (25(OH)D₃), 25-hydroxyvitamin D2 (25(OH)D₂), and total 25-hydroxyvitamin (25(OH)D) concentration with cognitive performance in older Americans. Methods: The data from the National Health and Nutrition Examination Survey (NHANES), 2011–2014 was used. The cognitive performance was assessed by the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) Word Learning sub-test, Animal Fluency test, and Digit Symbol Substitution Test (DSST). A binary logistic regression model was applied to evaluate the association between VD and cognitive performance, and restricted cubic spline model was adopted to evaluate the dose–response relationship. Results: While comparing to the lowest dietary VD intake group, the multivariate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of the highest dietary VD intake group were 0.51 (0.36–0.72) for the Animal Fluency test score and 0.45 (0.31–0.66) for DSST score, respectively; and those of serum total 25(OH)D and 25(OH)D₃ concentration were 0.68 (0.47–0.97) and 0.62 (0.44–0.86) for DSST score. L-shaped relationships were identified for dietary VD intake, serum total 25(OH)D and 25(OH)D₃ concentration with cognition performance. The associations between dietary VD intake, serum total 25(OH)D and cognitive performance were non-significant when stratified by gender. Conclusions: The study indicates that dietary VD intake, serum total 25(OH)D and 25(OH)D₃ concentration were positively associated with cognitive performance. Further studies are needed to clarify the possible effects of dietary VD intake and serum 25(OH)D₂, 25(OH)D₃ on cognitive performance.     

Association of Serum Vitamin D Concentration With Clinical Symptoms and Quality of Life in Patients With Irritable Bowel Syndrome

Objective: A high prevalence of vitamin D deficiency (VDD) in gastrointestinal (GI) disorders and the role of vitamin D in the function of the gut have been shown previously. Therefore, we aimed to evaluated the VDD and the possible association of the GI symptoms severity and quality of life (QoL) score with the serum levels of vitamin D in irritable bowel syndrome (IBS).

Methods: A total of 90 patients with IBS based on Rome III criteria enrolled in the study from the tertiary referral university hospital. In addition, 90 sex- and age-matched healthy controls (HCs) were recruited. To measure the serum levels of 25(OH)D₃, blood samples were taken from all the participants. Severity of clinical symptoms, IBS quality of life (IBS-QoL), and IBS symptom severity score (IBSSS) were assessed.

Results: In 66.7% of IBS patients, serum 25(OH)D₃ concentrations were <20?ng/mL. The mean serum 25(OH)D₃ of IBS patients was statistically (p?<?0.05) lower vs. HCs. When different subtypes were analyzed, the serum 25(OH)D₃ concentrations in diarrhea-predominant IBS were statistically (p?<?0.05) lower as compared to HCs. Furthermore, the lower serum concentrations of 25(OH)D₃ were associated (p?<?0.05) with higher severity of abdominal pain and distention, flatulence, overall GI symptoms, and IBSSS. However, a direct significant association was seen between IBS-QoL and serum 25(OH)D₃.

Conclusion: Results of this study showed a high prevalence of VDD in patients with IBS. In addition, VDD was associated with a higher severity of clinical symptoms and lower QoL in IBS.     

Assessing the Relationship between Vitamin D3 and Stratum Corneum Hydration for the Treatment of Xerotic Skin

Vitamin D₃ has been called the “sunshine” vitamin since the formation of vitamin D is mediated by exposure to sunlight. Vitamin D₃ is linked to many health benefits, however serum levels of vitamin D₃ have been decreasing over the last few decades and the lower levels of vitamin D₃ may have consequences on normal physiology. We investigated the association between serum 25-hydroxyvitamin D (25(OH)D) levels and stratum corneum conductance as well as the effect of topical application of cholecalciferol (vitamin D₃) on dry skin. Eighty three subjects were recruited and blood serum levels and skin conductance measurements were taken after a one week washout. A correlation was observed between vitamin D levels and skin moisture content, individuals with lower levels of vitamin D had lower average skin moisture. Subsequently, a 3-week split leg, randomized, vehicle controlled clinical study was conducted on a subset of 61 of the above individuals who were identified with non-sufficient vitamin D serum levels. Topical supplementation with cholecalciferol significantly increased measurements of skin moisturization and resulted in improvements in subjective clinical grading of dry skin. Taken together our finding suggest a relationship between serum vitamin D₃ (25(OH)D) levels and hydration of the stratum corneum and further demonstrate the skin moisture benefit from topical application of vitamin D₃.     

Vitamin D Metabolites and Clinical Outcome in Hospitalized COVID-19 Patients

(1) Background: Vitamin D, a well-established regulator of calcium and phosphate metabolism, also has immune-modulatory functions. An uncontrolled immune response and cytokine storm are tightly linked to fatal courses of COVID-19. The present retrospective study aimed to inves-tigate vitamin D status markers and vitamin D degradation products in a mixed cohort of 148 hospitalized COVID-19 patients with various clinical courses of COVID-19. (2) Methods: The serum concentrations of 25(OH)D₃, 25(OH)D₂, 24,25(OH)₂D₃, and 25,26(OH)₂D₃ were determined by a validated liquid-chromatography tandem mass-spectrometry method in leftover serum samples from 148 COVID-19 patients that were admitted to the University Hospital of the Medical Uni-versity of Graz between April and November 2020. Anthropometric and clinical data, as well as outcomes were obtained from the laboratory and hospital information systems. (3) Results: From the 148 patients, 34 (23%) died within 30 days after admission. The frequency of fatal outcomes did not differ between males and females. Non-survivors were significantly older than survivors, had higher peak concentrations of IL-6 and CRP, and required mechanical ventilation more frequently. The serum concentrations of all vitamin D metabolites and the vitamin D metabolite ratio (VMR) did not differ significantly between survivors and non-survivors. Additionally, the need for res-piratory support was unrelated to the serum concentrations of 25(OH)D vitamin D and the two vitamin D catabolites, as well as the VMR. (4) Conclusion: The present results do not support a relevant role of vitamin D for the course and outcome of COVID-19.     

Vitamin D Status in Malaysian Men and Its Associated Factors

Vitamin D insufficiency is a global health problem. The data on vitamin D status in Malaysian men is insufficient. This study aimed to investigate vitamin D status among Chinese and Malay men in Malaysia and its associating factors. A cross-sectional study was conducted on 383 men aged 20 years and above, residing in Klang Valley, Malaysia. Their age, ethnicity, body anthropometry and calcaneal speed of sound (SOS) were recorded. Their fasting blood was collected for serum 25-hydroxyvitamin D (25(OH)D), intact parathyroid (PTH), total calcium and inorganic phosphate assays. Vitamin D deficiency was defined as a serum 25(OH)D level <30 nmol/L and insufficiency as a serum 25(OH)D level between 30 and 50 nmol/L. The overall prevalence of vitamin D deficiency was 0.5%, and insufficiency was 22.7%. Vitamin D deficiency and insufficiency were more prevalent in the Malays compared to the Chinese. Being Chinese, older in age, having lower body mass index (BMI) and a high physical activity status were associated significantly with a higher serum 25(OH)D level (p < 0.05). The serum PTH level was inversely associated with the serum 25(OH)D level (p < 0.05). As a conclusion, a significant proportion of Malaysian men have vitamin D insufficiency, although deficiency is uncommon. Steps should be taken to correct the vitamin D status of these men.     

Vitamin D Deficiency and Insufficiency in the Georgia Older Americans Nutrition Program

ABSTRACT

Serum 25-hydroxyvitamin D (25(OH)D) status in older adults enrolled in community-based meal programs is not well characterized. The objective was to identify predictors of poor serum 25(OH)D status and the response to vitamin D supplementation in a convenience sample from the Older Americans Act Nutrition Program (OAANP) in northeast Georgia (N = 158, mean age = 77 years, 81% women, 69% Caucasian, 31% African American). Mean serum 25(OH)D was 55 nmol/l, and intakes of vitamin D and calcium from foods were very low. Vitamin D insufficiency (25(OH)D 25- < 50 nmol/l) occurred in 36.7%. Vitamin D deficiency occurred in 8.2% (25(OH)D < 25 nmol/l) and was associated with low milk intake, low sunlight exposure, receiving meals at home, tobacco use, depression, dementia, antianxiety medication, poor instrumental activities of daily living, and low calf circumference (p ≤ 0.05). When non-supplement users (n = 28) were given a multivitamin with vitamin D (10 µg/d) and calcium (450 mg/d) for 4 months, 25(OH)D increased from 50 to 78 nmol/l, the prevalence of poor vitamin D status (25(OH)D < 50 nmol/l) decreased from 61% to 14%, and serum alkaline phosphatase decreased by 10% (p < 0.01). High body weight appeared to attenuate the increase in 25(OH)D in response to the multivitamin supplement (p ≤ 0.05). In conclusion, OAANP services did not prevent poor vitamin D and calcium status, but a supplement with vitamin D and calcium was beneficial.     

Calcium Absorption Varies within the Reference Range for Serum 25-Hydroxyvitamin D

Background: Calcium absorption is generally considered to be impaired under conditions of vitamin D deficiency, but the vitamin D status that fully normalizes absorption is not known for humans.

Objective: To quantify calcium absorption at two levels of vitamin D repletion, using pharmacokinetic methods and commercially marketed calcium supplements.

Design: Two experiments performed in the spring of the year, one year apart. In the first, in which participants were pretreated with 25-hydroxyvitamin D (25OHD), mean serum 25OHD concentration was 86.5 nmol/L; and in the other, with no pretreatment, mean serum concentration was 50.2 nmol/L. Participants received 500 mg oral calcium loads as a part of a standard low calcium breakfast. A low calcium lunch was provided at mid-day. Blood was obtained fasting and at frequent intervals for 10 to 12 hours thereafter.

Methods: Relative calcium absorption at the two 25OHD concentrations was estimated from the area under the curve (AUC) for the load-induced increment in serum total calcium.

Results: AUC₉ (± SEM), was 3.63 mg hr/dL ± 0.234 in participants pretreated with 25OHD and 2.20 ± 0.240 in those not pretreated (P < 0.001). In brief, absorption was 65% higher at serum 25OHD levels averaging 86.5 nmol/L than at levels averaging 50 nmol/L (both values within the nominal reference range for this analyte).

Conclusions: Despite the fact that the mean serum 25OHD level in the experiment without supplementation was within the current reference ranges, calcium absorptive performance at 50 nmol/L was significantly reduced relative to that at a mean 25OHD level of 86 nmol/L. Thus, individuals with serum 25-hydroxyvitamin D levels at the low end of the current reference ranges may not be getting the full benefit from their calcium intake. We conclude that the lower end of the current reference range is set too low.     

Assessment of Vitamin D Metabolism in Patients with Cushing’s Disease in Response to 150,000 IU Cholecalciferol Treatment

In this study we aimed to assess vitamin D metabolism in patients with Cushing’s disease (CD) compared to healthy individuals in the setting of bolus cholecalciferol treatment. The study group included 30 adults with active CD and the control group included 30 apparently healthy adults with similar age, sex and BMI. All participants received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D₃, 25(OH)D₂, 1,25(OH)₂D₃, 3-epi-25(OH)D₃ and 24,25(OH)₂D₃), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. All data were analyzed with non-parametric statistics. Patients with CD had similar to healthy controls 25(OH)D₃ levels (p > 0.05) and higher 25(OH)D₃/24,25(OH)₂D₃ ratios (p < 0.05) throughout the study. They also had lower baseline free 25(OH)D levels (p < 0.05) despite similar DBP levels (p > 0.05) and lower albumin levels (p < 0.05); 24-h urinary free cortisol showed significant correlation with baseline 25(OH)D₃/24,25(OH)₂D₃ ratio (r = 0.36, p < 0.05). The increase in 25(OH)D₃ after cholecalciferol intake was similar in obese and non-obese states and lacked correlation with BMI (p > 0.05) among patients with CD, as opposed to the control group. Overall, patients with CD have a consistently higher 25(OH)D₃/24,25(OH)₂D₃ ratio, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. The observed difference in baseline free 25(OH)D levels is not entirely clear and requires further study.