Vitamin D Sufficiency Research Articles

Association of Vitamin D Levels with the Metabolic Profile and Sexual Maturation Stage of Adolescents

The deficiency of Vitamin D (VD) is widely prevalent worldwide in adults, but many studies show that this deficiency also affects adolescents and may be considered a global public health problem. The VD levels are particularly significant in adolescents since it influences several aspects of growth, development, and puberty. During this phase of life, both girls and boys develop reproductive aspects, and secondary sexual characteristics and the adequate nutritional status appear to be the prerequisite for normal pubertal development. Due to the importance of VD in adolescents, the objective of this study was to investigate the association of the levels of this vitamin with glycemic, lipid, and anthropometric profile and sexual maturation stages of adolescents. Anthropometric (weight and height) and biochemical (fasting glycemia, total cholesterol, HDL-c, LDL-c, and triglycerides) data and VD levels were collected in 67 adolescents. 66% of the adolescents showed VD sufficiency, 28% insufficiency, and 6% showed the deficiency. There was a significant difference in VD levels between the stages of sexual maturation for boys and girls. Overweight patients had lower serum VD levels. The correlation analysis indicated a positive correlation between VD and fasting glycemia and HDL-c, but with no significant difference. A negative correlation was observed between VD and cholesterol, LDL-c and triglycerides, but also with no significant difference. Once VD is crucial for bone health, and as it seems it is necessary to the homeostasis of glycemia, lipids, and body weight, we suggest that more studies should be conducted to confirm the precise role of this vitamin in the promotion and maintenance of health in this population.

Vitamin D Supplementation Reduces Induction of Epithelial-Mesenchymal Transition in Allergen Sensitized and Challenged Mice.

Asthma is a chronic disease of the lung associated with airway hyperresponsiveness (AHR), airway obstruction and airway remodeling. Airway remodeling involves differentiation of airway epithelial cells into myofibroblasts via epithelial-mesenchymal transition (EMT) to intensify the degree of subepithelial fibrosis. EMT involves loss in E-cadherin with an increase in mesenchymal markers, including vimentin and N-cadherin. There is growing evidence that vitamin D has immunomodulatory and anti-inflammatory properties. However, the underlying molecular mechanisms of these effects are still unclear. In this study, we examined the contribution of vitamin D on the AHR, airway inflammation and expression of EMT markers in the airways of mice sensitized and challenged with a combination of clinically relevant allergens, house dust mite, ragweed, and Alternaria (HRA). Female Balb/c mice were fed with vitamin D-sufficient (2000 IU/kg) or vitamin D-supplemented (10,000 IU/kg) diet followed by sensitization with HRA. The density of inflammatory cells in the bronchoalveolar lavage fluid (BALF), lung histology, and expression of EMT markers by immunofluorescence were examined. Vitamin D-supplementation decreased AHR, airway inflammation in the BALF and the features of airway remodeling compared to vitamin D-sufficiency in HRA-sensitized and -challenged mice. This was accompanied with increased expression of E-cadherin and decreased vimentin and N-cadherin expression in the airways. These results indicate that vitamin D may be a beneficial adjunct in the treatment regime in allergic asthma.

Low vitamin D level in pediatric patients with new onset type 1 diabetes is common, especially if in ketoacidosis.

Vitamin D deficiency (VDD) adversely affects bone health. US data on prevalence of VDD or vitamin D insufficiency (VDI) at diagnosis of type 1 diabetes (T1D) is lacking. Low serum 25-hydroxyvitamin D (25OHD) is speculated to increase the risk of developing T1D. Assess the prevalence of pediatric VDD and VDI at diagnosis of T1D, and investigate correlations with demographic and clinical parameters. We performed a retrospective Institutional Review Board (IRB)-approved chart review of all T1D cases diagnosed from January 2011 to August 2012, all having the same 25OHD assay performed at Quest Diagnostics. Definitions for VDD, VDI, and vitamin D sufficiency (VDS) were 25OHD levels (ng/mL) ≤ 20, 21-29, and ≥ 30, respectively. We termed 25OHD <30 ng/mL as Low-D. We identified 185 autoantibody positive T1D subjects (51% female) with 25OHD measured, 51% Caucasian, 25% Hispanic, 4% mixed-Hispanic, 4% African American, and 16% other/mixed race. Mean age 9.8 yr (0.9-18.6). Most had Low-D (58%), 40% VDI, 18% VDD, and 42% VDS. No gender or age differences among the 25OHD groups. Low-D was more common (p < 0.0001) in Hispanics (81%) vs Caucasians (44%), but VDD rates were similar. Low-D subjects were heavier than VDS (p = 0.018). All four with elevated celiac titers were VDS. Diabetic ketoacidosis was present in 33%, but more common (44%) in Low-D vs. VDS (18%) (p < 0.0001), and trended higher in VDD (61%) vs. VDI (36%). Seventy-seven percentage with DKA had Low-D. VDD and insufficiency are common, even in Caucasians, at onset of T1D in pediatrics, worse in those with DKA.

Insignificant medium-term vitamin D status change after 25-hydroxyvitamin D testing in a large managed care population.

ObjectivesTo examine the clinical utility of 25-hydroxyvitamin D (25(OH)D) testing in achieving medium-term vitamin D (VD) sufficiency in a managed care population.MethodsRetrospective study of a continuously-enrolled patient population in a 3-year period between 2011 and 2013. Primary outcome was VD status at ∼1 year after 25(OH)D testing. Patient demographics, comorbidities, medications, and 25(OH)D test results were gathered from relevant databases and multivariate logistic regression analysis used to study the risk factors of persistent VD deficiency or insufficiency.ResultsOf 22,784 patients, 7533 (females 69.3%) did 14,563 25(OH)D tests, with an estimated cost of $582,520. Of the 7533 patients, 1126 had another 25(OH)D test at 300–400 days after the first one. Based on the two test results, 234 patients (20.8%) maintained sufficient 25(OH)D levels; 132 (11.7%) turned from VD-sufficient into VD-insufficient or -deficient; 538 (47.8%) remained VD-insufficient or -deficient, and only 222 (19.7%) improved to be VD-sufficient. Overall, only 8.0% more patients were VD-sufficient at ∼1 year after 25(OH)D testing. Only younger age and higher BMI were independent risk factors for persistent low 25(OH)D levels and high-dose VD use was not associated with achieving VD sufficiency.Conclusions25(OH)D testing only benefits a small portion of patients thus lacks clinical utility in achieving VD sufficiency in the medium term but incurs a significant cost. A practical strategy to treat VD deficiency or insufficiency is needed; without it, 25(OH)D testing adds little value to most patients’ health and should be used with discretion.

The Role of 25-Hydroxy Vitamin D Deficiency in Iron Deficient Children of North India

Extensive data from animal and human studies indicate a role of vitamin D in erythropoiesis. Iron and vitamin D deficiencies are implicated with adverse health effects in children even if they are asymptomatic. The potential relationship between the two remains poorly understood. A cross-sectional study was performed in the period from 1st May 2012 through 30th April 2013 and subjects were classified into vitamin D deficiency (VDD), vitamin D insufficiency (VDI) and vitamin D sufficiency (VDS) groups according to their 25(OH) D levels. A total of 263 children were included in the analysis. Anaemia was present in 66% of 25(OH) D deficient subjects compared with 35% in vitamin D sufficient individuals (p<0.0001). The association of breast feeding and development of VDD was also significant (p<0.05). Serum levels of 25(OH) D were found lower in female sex and if the analysis was performed in the winter/spring season. Physicians should therefore assess vitamin D levels in all anaemic children and ensure adequate supplementation to prevent deficiencies.

The prevalence of vitamin D deficiency in iron-deficient and normal children under the age of 24 months

BackgroundIron and vitamin D deficiencies cause a variety of health issues in children, which might have long-lasting effects even in asymptomatic cases. The present study sought to elucidate the potential association between iron status and serum vitamin D levels in infants.MethodsWe evaluated 102 infants aged 3-24 months who visited the CHA Bundang Medical Center from August 2010 to July 2011. Questionnaire and laboratory data were collected. The infants were classified into iron deficiency anemia (IDA), iron deficiency (ID), and normal groups according to hemoglobin (Hb) and ferritin levels. They were then classified into vitamin D deficiency (VDD), vitamin D insufficiency (VDI), and vitamin D sufficiency (VDS) groups according to 25-hydroxyvitamin D [25(OH)D] levels.ResultsVDD was present in 67% of IDA, 53% of ID, and 29% of normal subjects. The proportion of breastfed infants was the highest in the IDA (97%) and VDD (96%) groups. The odds ratio for the likelihood of iron-deficient infants to have subnormal vitamin D levels was 4.115. There was a significant correlation between Hb and 25(OH)D levels. Plasma 25(OH)D levels were lower in the winter/spring. Body mass index values were higher in the IDA/ID groups. Iron, age, and season were predictors of 25(OH)D levels.ConclusionThe prevalence of iron and vitamin D deficiency was high in breastfed infants. There was also a significant association between Hb and 25(OH)D levels in infants. Since all breastfed infants should receive vitamin D supplementation, there should also be concern about concurrent deficiencies in infants with IDA.

Vitamin D status and skeletal health in black men starting androgen deprivation therapy for prostate cancer.

e15139 Background: Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with increased incidence of osteoporosis and fractures. However, much of this information is in Caucasian men. Our aim was to evaluate the prevalence low 25-hydroxyvitamin-D levels and low bone mass in black men starting ADT. Methods: A chart-based retrospective review was conducted on all patients diagnosed with PCa and were deemed appropriate to start ADT in a tertiary care center between September 2007 and July 2010. Baseline data were collected on vitamin-D status and bone mineral density (BMD). Vitamin-D sufficiency was defined as levels ≥30 ng/ml, insufficiency as &lt;30ng/ml and deficiency as ≤20ng/ml. Osteopenia was defined when T scores were between -1 to -2.5 and osteoporosis when T scores ≤ -2.5. Results: A total of 113 black men had evaluable data (mean age 68.9±9.0; range 45-92). At baseline, mean vitamin-D levels were 20.8±9.0 ng/ml (range 4.0-43.0), lumbar Spine T-score was -0.37±1.46 (range -4.20-3.34;) and femoral neck T-score was -0.94±1.04 (range -3.00-1.50). A total of 49.4% of our patients were vitamin-D deficient (13.5±4.6), 33.7% had insufficiency (24.5±3.1) and 16.9% had sufficient vitamin-D levels ( 34.7±4.3). 59.3% of patients had normal BMD, 31.5% had osteopenia and 9.3% had osteoporosis. Conclusions: A significant proportion of black men starting ADT have low Vitamin-D levels and low bone mass. These observations should be taken into account when starting ADT in black men.

The prevalence of metabolic risk factors in black men with prostate cancer undergoing consideration for androgen-deprivation therapy.

e15082 Background: Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with endocrine complications such as osteoporosis, weight gain, diabetes and dyslipidemia. However, in previous studies, the patient population has been predominantly white. The aim of this study was to examine relevant baseline characteristics, associated with the above-mentioned complications, in a predominantly black population presenting with prostate cancer for consideration of ADT. The information gained will help us to further risk stratify this population in regards to the possible complications of ADT. Methods: A chart-based retrospective review was conducted on all patients diagnosed with PCa presenting to one provider in an urban hospital between September 2007 and July 2010 who were being considered for ADT. Baseline data were collected on body mass index (BMI), Vitamin-D status, bone mineral density (BMD), lipid profile and diabetes status. Overweight and obesity were classified as BMI≥25 and BMI≥30, respectively, Vitamin-D sufficiency as ≥30 ng/ml, osteopenia as T scores between -1 to -2.5 and osteoporosis as T scores ≤ -2.5. Results: A total of 180 patients had sufficient data of which 71.1%, (n=128 patients, mean age 68.0 years; range 45-93) were black. Their origin was from 16 countries with 44.9 % being African Americans and 55.1% immigrants. At baseline, average BMI was 28.1±5.9 SD (range 15.4-58.5; n=104) with 42.3% of patients being overweight and an additional 31.7% obese. Mean Vitamin-D levels were 21.1±9.7 SD (range 4.0-48.0; n=93) and 80.7% of patients were Vitamin-D insufficient. Osteopenia and osteoporosis were present in 46.8% and 6.4%, respectively. Dyslipidemia was present in 40.6% of patients and 28.1% had diabetes. Conclusions: A large proportion of black men with PCa presenting for consideration of ADT are either overweight or obese at baseline. The prevalence of Vitamin-D insufficiency, low BMD, dyslipidemia and diabetes is also remarkably high. These data should be helpful for physicians considering ADT in this population.