Common vitamin D pathway gene variants reveal contrasting effects on serum vitamin D levels in African Americans and European Americans

A recent meta-analysis of cohort studies with participants primarily of European ancestry, concluded that the risk of incident diabetes was inversely proportional to serum 25-hydroxy-vitamin D levels (25-OH-D). African Americans have lower levels of vitamin D than European Americans. But, lower levels of vitamin D do not seem to carry the same risk for low bone density or vascular calcification for African Americans. We sought to test the hypothesis that low vitamin D elevates the risk of diabetes in African Americans. During 2001-5, 5301 African American adults in Jackson, MS, were examined and blood samples drawn; mean age was 55±13. Serum 25-OH-D2 and 25-OH-D3 were measured from stored frozen serum; mean total 25-OH-D (25-OH-D2 plus 25-OH-D3) =14.5±6.7ng/ml. A seasonal pattern was evident for 25-OH-D3 but not for 25-OH-D2 levels. A cosinor model adjusted for seasonality of 25-OH-D3; mean annualized concentrations and seasonal amplitude were significantly higher for men and for persons of normal BMI compared to overweight or obese persons. Total 25-OH-D, as the sum of predicted annualized mean 25-OH-D3 and measured 25-OH-D2, was used in subsequent analysis. The analysis evaluated 3363 participants after exclusions for missing serum vitamin D (n=141), prevalent diabetes (n=1152), incomplete ascertainment of diabetes (n=62), or no follow-up (n=725). During a mean follow-up of 7.1 years, there were 584 new cases of diabetes. Using a Cox Proportional Hazards model controlling for age and sex, the risk of incident diabetes was significantly and inversely associated with total serum 25-OH-D; after adding BMI to the model, 25-OH-D was not significantly associated with risk of diabetes (Table 1). Physical activity, smoking, and alcohol use did not predict incident diabetes in any model. In conclusion, we found that in this cohort of African-Americans, with low mean 25-OH-D and a relatively narrow range of 25-OH-D, the risk of incident diabetes was not associated with serum 25-OH-D levels after controlling for sex, age, and BMI.

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Relationship between Microalbuminuria and Serum Vitamin D Levels in African Americans with Type 2 Diabetes

The FASEB Journal ◽

10.1096/fasebj.29.1_supplement.902.6 ◽

2015 ◽

Vol 29 (S1) ◽

Author(s):

Gustavo Zarini ◽

Lemia Shaban ◽

Joel Exebio ◽

Joan Vaccaro ◽

Sahar Ajabshir ◽

...

Keyword(s):

Type 2 Diabetes ◽

Vitamin D ◽

African Americans ◽

Serum Vitamin ◽

Serum Vitamin D ◽

Vitamin D Levels

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Clinical factors correlated with vitamin D deficiency in patients with obesity scheduled for bariatric surgery: A single center experience

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000662 ◽

2020 ◽

Vol 90 (3-4) ◽

pp. 346-352

Author(s):

Vincenzo Pilone ◽

Salvatore Tramontano ◽

Carmen Cutolo ◽

Federica Marchese ◽

Antonio Maria Pagano ◽

...

Keyword(s):

Bariatric Surgery ◽

Vitamin D ◽

Vitamin D Deficiency ◽

Serum Vitamin ◽

Inverse Correlation ◽

Model Assessment ◽

Cross Sectional ◽

Serum Vitamin D ◽

Female Sex ◽

Vitamin D Levels

Abstract. We aim to assess the prevalence of vitamin D deficiency (VDD) in patients scheduled for bariatric surgery (BS), and to identify factors that might be associated with VDD. We conducted a cross-sectional observational study involving all consecutive patients scheduled for BS from 2017 to 2019. The exclusion criteria were missing data for vitamin D levels, intake of vitamin D supplements in the 3 months prior to serum vitamin D determination, and renal insufficiency. A total of 206 patients (mean age and body mass index [BMI] of 34.9 ± 10.7 years, and 44.3 ± 6.99 kg/m2, respectively) met the inclusion criteria and were enrolled for data analysis. VDD (<19.9 ng/mL), severe VDD (<10 ng/mL), and vitamin D insufficiency (20–29.9 ng/mL) were present in 68.8 %, 12.5 %, and 31.2 % of patients, respectively. A significant inverse correlation was found between vitamin D levels and initial BMI, parathyroid hormone, and homeostatic model assessment of insulin resistance (r = −0.280, p < 0.05; r = −0.407, p = 0.038; r = −0.445, p = 0.005), respectively. VDD was significantly more prevalent in patients with higher BMI [−0.413 ± 0.12, CI95 % (−0.659; −0.167), p = 0.006], whereas no significant association between hypertension [−1.005 ± 1.65, CI95 % (−4.338; 2.326), p = 0.001], and diabetes type 2 (T2D) [−0.44 ± 2.20, CI95 % (−4.876; 3.986), p = 0.841] was found. We observed significant association between female sex and levels of vitamin D [6.69 ± 2.31, CI95 % (2.06; 11.33), p = 0.006]. The present study shows that in patients scheduled for BS, VDD deficiency is common and was associated with higher BMI, and female sex.

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Maternal Serum Vitamin D Levels During Pregnancy and Offspring Neurocognitive Development

PEDIATRICS ◽

10.1542/peds.2011-2644d ◽

2012 ◽

Vol 129 (3) ◽

pp. X11-X11

Keyword(s):

Vitamin D ◽

Serum Vitamin ◽

Maternal Serum ◽

Neurocognitive Development ◽

Serum Vitamin D ◽

Vitamin D Levels

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Faculty Opinions recommendation of Decreased serum vitamin D levels in children with asthma are associated with increased corticosteroid use.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.3437965.3141061 ◽

2010 ◽

Author(s):

Leonard Bacharier ◽

Avraham Beigelman

Keyword(s):

Vitamin D ◽

Serum Vitamin ◽

Serum Vitamin D ◽

Vitamin D Levels ◽

Children With Asthma

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Association of Vitamin D Levels and Other Risk Factors with Asthma Exacerbations in Children

Pakistan Journal of Medicine and Dentistry ◽

10.36283/pjmd9-4/004 ◽

2020 ◽

Keyword(s):

Risk Factors ◽

Vitamin D ◽

Serum Vitamin ◽

Persistent Asthma ◽

Food Allergies ◽

P Value ◽

Serum Vitamin D ◽

Asthma Exacerbations ◽

Vitamin D Levels ◽

Animal Dander

Background: The risk factors for asthma exacerbations are well understood. However, the effect of vitamin D levels on number of asthma exacerbations per year is not clearly studied. The objective of the study was to ﬁnd out the association of serum vitamin D levels and asthma risk factors on asthma exacerbations. Methods: In this study, ninety-nine subjects from 5 to 15 years of age were recruited at an episode of acute exacerbation. It was a cross sectional study and carried out from 2012 to 2015. Pulmonary function test was done by spirometry. Asthma exacerbation was labeled when forced expiratory volume/ forced vital capacity (FEV1/FVC) ratio was less than 80% (American Thoracic Society). Global Initiative for Asthma (GINA) guidelines were used to classify asthma into mild, moderate and severe persistent asthma. Serum vitamin D levels were measured by chemiluminescence method. Pearson Chi-square test was applied and p value (p<0.05) was considered as statistically signiﬁcant. Results: Children who had exposure to animal dander had signiﬁcantly lower asthma exacerbations per year (p-value <0.046). There was no signiﬁcant association between vitamin D levels and number of exacerbations per years (p-value <0.099). Asthma was prevalent in girls of low socioeconomic status (SES) compared to males. However, there was no signiﬁcant association between smoke, exercise, home environment, food allergies, weather, pollen and dust with asthma exacerbations. Conclusion: Low levels of vitamin D were not associated with increased number of asthma exacerbations per year. However, children exposed to animal dander had lesser number of exacerbations per year (p-value <0.046). Keywords: Asthma; Vitamin D; Children; Exacerbations, Risk factors.

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