Racial and seasonal differences in 25-hydroxyvitamin D detected in maternal sera frozen for over 40 years

Serum banks from large, decades-old epidemiological studies provide a valuable opportunity to explore the contributions ofin uterovitamin D exposure to fetal origins of adult diseases. We compared 25-hydroxyvitamin D (25(OH)D) by race and season (two powerful predictors of vitamin D status) in sera frozen for ≥ 40 years with sera frozen for ≤ 2 years to determine whether 25(OH)D is stable enough to test vitamin D-related hypotheses. Data and sera came from seventy-nine pregnant women at 29–32 weeks' gestation in the Boston Collaborative Perinatal Project (CPP; 1959–66) and 124 women at 20–36 weeks' gestation in a 2003–2006 Pittsburgh cohort study. Multivariable linear regression models were used to test main and joint effects of race and season after confounder adjustment. In both cohorts, serum 25(OH)D levels were lower among black than white women (CPP 33·3v.46·7 nmol/l,P < 0·01; Pittsburgh 47·1v.89·6 nmol/l;P < 0·0001) and in winter than summer (CPP 32·7v.47·6 nmol/l,P < 0·0001; Pittsburgh 66·7v.89·8 nmol/l,P < 0·001), with no evidence of a race × season interaction in either cohort. Differences remained significant after confounder adjustment. When CPP and Pittsburgh results were compared, there was no significant difference in the race or season effects. The similarity in the relative change in 25(OH)D in these cohorts by two powerful predictors of vitamin D status suggests that, even if 25(OH)D deteriorated somewhat, it did so similarly across samples. Therefore, trends could be obtained from the decades-old serum data that would be relevant in exploring vitamin D-related hypotheses in future studies.

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Vitamin D status in children with autoimmune thyroiditis

International Journal of Contemporary Pediatrics ◽

10.18203/2349-3291.ijcp20173125 ◽

2017 ◽

Vol 4 (5) ◽

pp. 1595

Author(s):

Gomathi Priya J ◽

Seenivasan Venkatasamy ◽

Karamath S Pyarejan ◽

Jayachandran K.

Keyword(s):

Vitamin D ◽

Alkaline Phosphatase ◽

Serum Calcium ◽

Autoimmune Thyroiditis ◽

Causal Factor ◽

Vitamin D Status ◽

Hydroxyvitamin D ◽

Vitamin D Levels ◽

Significant Difference ◽

25 Hydroxyvitamin D

Background: Deficiency of 25 hydroxyvitamin D has been linked with predisposition to autoimmune disorders. Also, vitamin D has been found to be a causal factor in many autoimmune diseases. Objective of the study was to investigate vitamin D status in children with autoimmune thyroiditis attending endocrinology OPD at a tertiary centre in southern India.Methods: It is a case control study done in which 75 children (70 female, 5 male) with age and sex matched healthy controls were chosen. Free thyroxine, TSH, anti TPOAb, anti TGAb, 25 hydroxyvitamin D, serum calcium, phosphorus, alkaline phosphatase levels were estimated in both cases and control subjects. Children with anti TPO or anti TG positivity were divided into four groups based on their level of antibody titers.Results: The mean age in cases was 9.8±0.34 years. 25(OH)D levels were significantly lower in cases (15.07±1.14 ng/ml) compared to controls (17.82±1.13 ng/ml) (p<0.0006). Mean serum calcium levels in cases (9.35±0.16 mg/dl) were significantly lower when compared to controls (9.73±0.14 mg/dl) (p<0.0005). Similarly mean serum alkaline phosphatase level in cases (184.97±11.10 IU/L) were significantly elevated when compared with controls (122.37±6.82 IU/L) (p<0.0001). However, there was no significant difference in serum phosphorus levels between cases (4.42±0.10 mg/dl) and controls (4.43±0.14 mg/dl) (p=0.83). There was no significant difference in vitamin D level among the groups in both anti TPO (p< 0.283) and anti TG (p<0.148).Conclusions: The significant decrease in vitamin D levels in cases signifies that 25(OH)D may be an independent causal factor related to the autoimmunity in thyroid diseases.

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

Nutrients ◽

10.3390/nu12123872 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3872

Author(s):

Soriah M. Harvey ◽

Vanessa E. Murphy ◽

Peter G. Gibson ◽

Michael Clarke ◽

Megan E. Jensen

Keyword(s):

Vitamin D ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Plasma Concentrations ◽

Sample Type ◽

Vitamin D Status ◽

Hydroxyvitamin D ◽

Significant Difference ◽

25 Hydroxyvitamin D ◽

The Impact

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.

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UV and dietary predictors of serum 25-hydroxyvitamin D concentrations among young shift-working nurses and implications for bone density and skin cancer

Public Health Nutrition ◽

10.1017/s1368980013001754 ◽

2013 ◽

Vol 17 (4) ◽

pp. 772-779 ◽

Cited By ~ 6

Author(s):

Sarah C Wallingford ◽

Glenville Jones ◽

Lindsay C Kobayashi ◽

Anne Grundy ◽

Qun Miao ◽

...

Keyword(s):

Vitamin D ◽

White Women ◽

Full Time ◽

Institute Of Medicine ◽

Vitamin D Status ◽

Hydroxyvitamin D ◽

Supplement Use ◽

Tanning Bed ◽

25 Hydroxyvitamin D ◽

Vitamin D Supplements

AbstractObjectiveIn 2011, the US Institute of Medicine updated the definition of vitamin D inadequacy to serum 25-hydroxyvitamin D (25(OH)D) concentration of 30–<50 nmol/l and of deficiency to serum 25(OH)D < 30 nmol/l. We describe the prevalence of these conditions according to these definitions, seasonal variation in 25(OH)D and predictors of serum 25(OH)D concentrations among working, white women.DesignParticipants recorded lifestyle factors and dietary intake and provided fasting blood samples for measurement of serum 25(OH)D in both summer and winter. Predictors of serum 25(OH)D variation were analysed using linear regression and generalized linear mixed models.SettingKingston General Hospital in Kingston, Ontario, Canada, from April 2008 to July 2009.SubjectsFemale premenopausal nurses (n83) working full-time rotating shifts.ResultsDeficient or inadequate vitamin D status was observed in 9 % of participants following summer/autumn and in 13 % following winter/spring. Predictors of serum 25(OH)D concentration were vitamin D supplement use, tanning bed use and season. Tanning bed use increased serum 25(OH)D by 23·24 nmol/l (95 % CI 8·78, 37·69 nmol/l,P= 0·002) on average.ConclusionsAccording to the 2011 Institute of Medicine bone health guidelines, over 10 % of nurses had deficient or inadequate vitamin D status following winter. Higher serum concentrations were associated with use of tanning beds and vitamin D supplements. As health promotion campaigns and legal restrictions are successful in reducing tanning bed use among women, our data suggest that increased prevalence of vitamin D inadequacy and deficiency may be a consequence, and that low vitamin D status will need to be countered with supplementation.

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Distribution and Determinants of Vitamin D-Binding Protein, Total, “Non-Bioavailable”, Bioavailable, and Free 25-Hydroxyvitamin D Concentrations among Older Adults

Nutrients ◽

10.3390/nu13113982 ◽

2021 ◽

Vol 13 (11) ◽

pp. 3982

Author(s):

Anna Zhu ◽

Sabine Kuznia ◽

Tobias Niedermaier ◽

Bernd Holleczek ◽

Ben Schöttker ◽

...

Keyword(s):

Older Adults ◽

Vitamin D ◽

Health Outcomes ◽

Binding Protein ◽

Vitamin D Status ◽

Linear Regression Models ◽

Vitamin D Binding Protein ◽

Hydroxyvitamin D ◽

Reactive Protein ◽

25 Hydroxyvitamin D

Background: serum 25-hydroxyvitamin D (25(OH)D) (“total 25 OH(D)”) is the most commonly used indicator of vitamin D status. However, 25(OH)D is mostly bound to the vitamin D binding protein (VDBP) or albumin in blood, and it has been suggested that the remaining bioavailable or free 25(OH)D may be more relevant for vitamin D associated health outcomes. We aimed to explore distributions and determinants of VDBP, total, bioavailable, complementary “non-bioavailable”, and free 25(OH)D in a large cohort of older adults in Germany. Methods: total 25(OH)D, VDBP, and albumin concentrations were measured in blood samples of 5899 men and women aged 50–75 years and used to calculate bioavailable (and complementary “non-bioavailable”) and free 25(OH)D concentrations. Linear regression models were used to evaluate associations of potential determinants of the various vitamin D biomarkers. Results: mean concentrations of VDBP, total, non-bioavailable, bioavailable, and free 25(OH)D were 323.6 µg/mL, 49.8 nmol/L, 43.4 nmol/L, 2.5 ng/mL, and 5.7 pg/mL, respectively. Seasonal variations were observed for all markers, with peak values in spring for VDBP and in summer for total, non-bioavailable, bioavailable, and free 25(OH)D. Consistent inverse associations were seen with age and body mass index for all markers, but divergent associations were seen with C-reactive protein. Strong variations by VDBP genotypes were seen for bioavailable and free 25(OH)D, and, in opposite direction for non-bioavailable 25(OH)D. Conclusion: commonalities and differences in determinants of various markers of vitamin D status were observed, which may help to enable a better understanding of their potential role for various vitamin D related health outcomes.

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Comparison of Vitamin D and 25-Hydroxyvitamin D Concentrations in Human Breast Milk between 1989 and 2016–2017

Nutrients ◽

10.3390/nu13020573 ◽

2021 ◽

Vol 13 (2) ◽

pp. 573

Author(s):

Naoko Tsugawa ◽

Mayu Nishino ◽

Akiko Kuwabara ◽

Honami Ogasawara ◽

Maya Kamao ◽

...

Keyword(s):

Vitamin D ◽

Breast Milk ◽

Sun Exposure ◽

Stepwise Multiple Regression ◽

Human Breast Milk ◽

Vitamin D Status ◽

Human Breast ◽

Hydroxyvitamin D ◽

Lactating Mothers ◽

25 Hydroxyvitamin D

Background: Breast milk is considered the optimal source of nutrition during infancy. Although the vitamin D concentration in human breast milk is generally considered poor for infants, vitamin D in breast milk is an important source for exclusively breastfed infants. Increases in vitamin D insufficiency and deficiency in lactating mothers may reduce vitamin D concentrations in breast milk. This study aimed to compare vitamin D and 25-hydroxyvitamin D (25OHD) concentrations in breast milk collected in 1989 and 2016–2017 and simultaneously analyze them with liquid chromatography-tandem mass spectrometry (LC-MS/MS); the association between the lifestyle of recent lactating mothers (2016–2017) and vitamin D status in human breast milk was also evaluated. Method: Lactating mothers were recruited from three regions of Japan in 1989 (n = 72) and 2016–2017 (n = 90), and milk from 3–4 months was collected in summer and winter. The samples were strictly sealed and stored at −80℃ until measurement. Breast milk vitamin D and 25OHD concentrations were analyzed by LC-MS/MS. Vitamin D intake, sun exposure, and sunscreen use of the lactating mothers in 2016–2017 were assessed. Results: Both vitamin D and 25OHD concentrations in breast milk were higher in the summer regardless of the survey year. Significantly lower vitamin D and 25OHD concentrations were observed in 2016–2017 compared with 1989 in summer, but no survey year difference was observed in winter. The stepwise multiple regression analyses identified season, daily outdoor activity, and suntan in the last 12 months as independent factors associated with vitamin D3 concentrations. Conclusion: The results suggest that low vitamin D status in recent lactating mothers may have decreased vitamin D and 25OHD concentrations in breast milk compared with the 1980s. These results are helpful for developing public health strategies to improve vitamin D status in lactating mothers and infants.

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Serum 25-Hydroxyvitamin D Concentrations and Cardiometabolic Biomarkers in Chinese Rural Population

Hormone and Metabolic Research ◽

10.1055/a-1342-7098 ◽

2021 ◽

Vol 53 (02) ◽

pp. 105-111

Author(s):

Dongdong Zhang ◽

Cheng Cheng ◽

Yan Wang ◽

Yuan Xue ◽

Yiming Liu ◽

...

Keyword(s):

Vitamin D ◽

Vitamin D Deficiency ◽

Rural Population ◽

Density Lipoprotein ◽

Cubic Spline ◽

Lipoprotein Cholesterol ◽

Linear Regression Models ◽

Hydroxyvitamin D ◽

Linear Association ◽

25 Hydroxyvitamin D

AbstractThere is a paucity of data on the relation between serum 25-hydroxyvitamin D [25(OH)D] concentration and cardiometabolic biomarkers in the Chinese population. To comprehensively and quantitatively examine the association of 25(OH)D and cardiometabolic traits, we conducted a cross-sectional study in the Chinese rural population. Serum 25(OH)D and eight cardiometabolic biomarkers were measured in 1714 individuals from Henan province, China. Scatter plot was used to visualize the distribution and correlation of 25(OH)D and cardiometabolic indicators. Moreover, multivariate linear regressions and restricted cubic spline (RCS) functions were performed to examine the quantitative association between the serum 25(OH)D and cardiometabolic parameters. The median serum 25(OH)D level was 19.94 ng/ml in all participants, with an estimated 50.12% presenting vitamin D deficiency. Serum 25(OH)D level showed significantly modest association with cardiometabolic parameters (p<0.05) except for diastolic blood pressure (r=0.03, p=0.22). Multiple linear regression models showed that 25(OH)D concentration was positively associated with high-density lipoprotein cholesterol (HDL-C) and negatively associated with low-density lipoprotein cholesterol (LDL-C) and fasting serum glucose (GLU). The results of restricted cubic spline models indicated a positively linear association of 25(OH)D with HDL-C (p for overall<0.001, p for nonlinearity=0.191) and a negatively linear association with GLU (p for overall=0.024, p for nonlinearity=0.095). Overall, vitamin D deficiency was very common among Chinese rural population living near the 34 degrees north latitude. Besides, there were significant association between 25(OH)D concentrations and cardiometabolic biomarkers including HDL-C and GLU levels. Future longitudinal studies and randomized trials are warranted to clarify the causal relationship.

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COVID-19 Disease Severity and Death in Relation to Vitamin D Status among SARS-CoV-2-Positive UAE Residents

Nutrients ◽

10.3390/nu13051714 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1714

Author(s):

Habiba AlSafar ◽

William B. Grant ◽

Rafiq Hijazi ◽

Maimunah Uddin ◽

Nawal Alkaabi ◽

...

Keyword(s):

Vitamin D ◽

United Arab Emirates ◽

Blood Levels ◽

Vitamin D Status ◽

Hospital Visit ◽

Serum Samples ◽

Hydroxyvitamin D ◽

Increased Risk ◽

Multiethnic Population ◽

25 Hydroxyvitamin D

Insufficient blood levels of the neurohormone vitamin D are associated with increased risk of COVID-19 severity and mortality. Despite the global rollout of vaccinations and promising preliminary results, the focus remains on additional preventive measures to manage COVID-19. Results conflict on vitamin D’s plausible role in preventing and treating COVID-19. We examined the relation between vitamin D status and COVID-19 severity and mortality among the multiethnic population of the United Arab Emirates. Our observational study used data for 522 participants who tested positive for SARS-CoV-2 at one of the main hospitals in Abu Dhabi and Dubai. Only 464 of those patients were included for data analysis. Demographic and clinical data were retrospectively analyzed. Serum samples immediately drawn at the first hospital visit were used to measure serum 25-hydroxyvitamin D [25(OH)D] concentrations through automated electrochemiluminescence. Levels < 12 ng/mL were significantly associated with higher risk of severe COVID-19 infection and of death. Age was the only other independent risk factor, whereas comorbidities and smoking did not contribute to the outcomes upon adjustment. Sex of patients was not an important predictor for severity or death. Our study is the first conducted in the UAE to measure 25(OH)D levels in SARS-CoV-2-positive patients and confirm the association of levels < 12 ng/mL with COVID-19 severity and mortality.

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Vitamin D Status and Seasonal Variation among Danish Children and Adults: A Descriptive Study

Nutrients ◽

10.3390/nu10111801 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1801 ◽

Cited By ~ 20

Author(s):

Louise Hansen ◽

Anne Tjønneland ◽

Brian Køster ◽

Christine Brot ◽

Rikke Andersen ◽

...

Keyword(s):

Vitamin D ◽

Seasonal Variation ◽

Vitamin D Status ◽

Hydroxyvitamin D ◽

Supplement Use ◽

Wide Range ◽

Adults And Children ◽

25 Hydroxyvitamin D ◽

Vitamin D Supplement ◽

Very High

The aim of the present study was to describe vitamin D status and seasonal variation in the general Danish population. In this study, 3092 persons aged 2 to 69 years (2565 adults, 527 children) had blood drawn twice (spring and autumn) between 2012 and 2014. A sub-sample of participants had blood samples taken monthly over a year. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by liquid chromatography mass spectrometry, and information on supplement use was assessed from questionnaires. Seasonal variations in 25(OH)D concentrations were evaluated graphically and descriptively, and status according to age, sex, and supplement use was described. It was found that 86% of both adults and children were vitamin D-sufficient in either spring and or/autumn; however, many had a spring concentration below 50 nmol/L. A wide range of 25(OH)D concentrations were found in spring and autumn, with very low and very high values in both seasons. Among adults, women in general had higher median 25(OH)D concentrations than men. Furthermore, vitamin D supplement use was substantial and affected the median concentrations markedly, more so during spring than autumn. Seasonal variation was thus found to be substantial, and bi-seasonal measurements are vital in order to capture the sizable fluctuations in vitamin D status in this Nordic population.

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Weight and skin colour as predictors of vitamin D status: results of an epidemiological investigation using nationally representative data

Public Health Nutrition ◽

10.1017/s1368980016000173 ◽

2016 ◽

Vol 20 (10) ◽

pp. 1857-1864 ◽

Cited By ~ 5

Author(s):

Sonali Rajan ◽

Tom Weishaar ◽

Bryan Keller

Keyword(s):

Vitamin D ◽

Body Weight ◽

Skin Colour ◽

Vitamin D Status ◽

Epidemiological Investigation ◽

Dietary Recommendations ◽

Hydroxyvitamin D ◽

25 Hydroxyvitamin D ◽

Nationally Representative ◽

The Impact

AbstractObjectiveCurrent US dietary recommendations for vitamin D vary by age. Recent research suggests that body weight and skin colour are also major determinants of vitamin D status. The objective of the present epidemiological investigation was to clarify the role of age as a predictor of vitamin D status, while accounting for body weight and skin colour, among a nationally representative sample.DesignWe calculated the mean serum 25-hydroxyvitamin D levels for the US population by age and weight, as well as by weight and race/ethnicity group. Multiple regression analyses were utilized to evaluate age and weight as predictors of vitamin D status: serum 25-hydroxyvitamin D levels with age alone, age and body weight, and age, body weight and their two-way interaction were modelled for the entire sample and each age subgroup. Graphical data were developed using B-spline non-linear regression.SettingNational Health and Nutrition Examination Survey (31 934 unweighted cases).SubjectsIndividuals aged 1 year and older.ResultsThere were highly significant differences in mean vitamin D status among US residents by weight and skin colour, with those having darker skin colour or higher body weight having worse vitamin D status. Although a significant factor, the impact of age on vitamin D status was notably less than the impact of body weight.ConclusionsVitamin D status varied predominantly by body weight and skin colour. Recommendations by nutritionists for diet and supplementation needs should take this into account if vitamin D-related health disparities are to be meaningfully reduced across the USA.

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