Serum Concentrations Of 25-hydroxyvitamin Research Articles

Chronic Latent Magnesium Deficiency in Obesity Decreases Positive Effects of Vitamin D on Cardiometabolic Risk Indicators.

Obesity and micronutrient deficiencies contribute to the risk of cardiometabolic diseases such are type 2 diabetes mellitus and Cardiovascular Disease (CVD). We examined the frequency of concomitant deficit of Magnesium (Mg) and vitamin D in obese patients and evaluated the connection of these combined deficiencies with indicators of cardiometabolic risk in non-diabetic subjects. Non-diabetic middle aged adults (n = 80; mean age 36 ± 4 years, 52% women) were recruited based on weight/adiposity parameters [i.e. Body Mass Index (BMI) and body fat percentage (FAT%)]. Cardiometabolic risk indicators [insulin resistance (Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)) and CVD risk (Framingham risk score for predicting 10-year CVD)], Mg status (i.e. total serum Mg concentration (TMg), Chronic Latent Mg Deficiency (CLMD) - 0.75-0.85 mmol/L), vitamin D status (i.e. serum concentration of 25-hydroxyvitamin D (25(OH)D), vitamin D deficiency <50 nmol/l) were assessed. Among obese subjects 36% presented a combination of vitamin D deficiency and CLMD. In all studied patients, 25(OH)D and TMg levels both, individually and combined, showed a negative linear correlation with HOMA-IR and CVD risk. In subjects with CLMD (TMg <0.85 mmol/L), a negative linear coefficient was found between 25(OH)D and, HOMA-IR and CVD risk, compared with subjects with normal TMg status (TMg ≥0.85 mmol/L). CLMD and vitamin D deficiency may commonly be present in obese non-diabetic subjects. Individually and combined, both deficiencies predispose non-diabetic patients to increased risk of cardiometabolic diseases. Maintaining normal Mg status may improve the beneficial effects of vitamin D on cardiometabolic risk indicators.

Association between Vitamin D Deficiency and Single Nucleotide Polymorphisms in the Vitamin D Receptor and GC Genes and Analysis of Their Distribution in Mexican Postmenopausal Women.

Genome-wide association studies in people with European ancestry suggest that polymorphisms in genes involved in vitamin D (VD) metabolism have an effect on serum concentrations of 25-hydroxyvitamin D. However, nothing is known about these polymorphisms in populations with Amerindian ancestry. Our aim was to evaluate the association between genetic variants on the vitamin D receptor (VDR) and the vitamin D binding protein (GC) genes, involved in the VD pathway, and VD deficiency in 689 unrelated Mexican postmenopausal women. We also described the frequencies of these variants in 355 postmenopausal women from different ethnic groups. Based on our preliminary results of 400 unrelated Mexican postmenopausal women, three single nucleotide polymorphisms (SNPs) were selected for genotyping. The SNPs rs4516035 in VDR and rs2282679 in GC were associated with VD deficiency. Additionally, women who carried three risk alleles had a 3.67 times higher risk of suffering VD deficiency, compared to women with no risk alleles (p = 0.002). The rs4516035-C allele frequency in the Amerindian population was enriched in the South East region of Mexico. In contrast, the highest frequency of the rs2298850-C allele, a proxy for the tag SNP rs2282679, was observed in the South region. Our results indicate that genetic variants in VDR and GC genes are associated with VD deficiency in Mexican postmenopausal women. Moreover, an association was observed for the variants rs3794060 and rs4944957 of the DHCR7/NADSYN1 gene with osteopenia/osteoporosis.

16. A study of correlation between disturbances in calcium-pth-vitamin D axis and clinical severity of non cholestatic chronic liver disease

Background and Aims: The role of disturbance in Calcium-PTH-Vitamin D axis has been debated in people with Chronic Liver Disease (CLD) as liver is a important organ involved in Vitamin D metabolism. We aim to determine the prevalence, extent and amount of disturbance in serum calcium, parathyroid hormone (PTH) and Vitamin D in CLD patients and their correlation with severity of CLD. Methods: It is a prospective, cross sectional observational study. 80 patients (55 males & 25 females; mean age 47.06 ± 12.53 years) data was collected with confirmed diagnosis of non-cholestatic CLD between Nov 2017 and April 2018 and were graded severity with Child-Turcotte-Pugh (CTP) and Model for End Stage Liver Disease (MELD) score. Serum concentrations of 25-hydroxyvitamin D{25 (OH)D}, PTH, PT/INR, calcium, phosphorus, LFT were done. Fibroscan was done in all patients. Results: Causes of cirrhosis was Alcohol (n = 30), Hepatitis B (n = 20), Hepatitis C (n = 4), NASH (n = 9), Autoimmune (n = 2), Wilson (n = 3), cirrhosis secondary to EHPVO (n = 6) and NCPF (n = 6). Total Patients with CTP A (n = 26), CTP B (n = 30), and CTP C (n = 24). Serum 25 (OH)D levels were inadequate in 78 out of 80 patients. Vitamin D deficiency (<20 ng/ml) was found in 60 patients and Vitamin D insufficiency (20–30 ng/ml) found in 18 patients. Only 2 patients had adequate serum Vitamin D levels (>30 ng/ml). Secondary hyperparathyroidism (serum PTH > 65 pg/ml) was seen in only in 5 patients. Patients with CTP score >9 had significantly lower serum 25 (OH)D compared to CTP score <7[10.33 ± 2.85 ng/ml vs. 19.02 ± 7.41 ng/ml; p < 0.001]. Significant correlation was found between high Fibroscan value (>27 kPa) and lower serum 25 (OH)D (<20 ng/ml) levels (p < 0.001). Serum Vitamin D deficiency was predictive of coagulopathy, hyperbilirubinimea, hypoalbunemia, high MELD score and high fibrosis. Conclusions: Lower Vitamin D levels are very common in chronic liver disease even in absence of cholestasis. Serum vitamin D levels showed significant correlation with severity of CLD. Management and Treatment protocol for patients of CLD should include assessment and replacement of vitamin D wherever necessary. The authors have none to declare.

Prevalence and predictors of subclinical micronutrient deficiency in German older adults: Results from the population-based KORA-Age study

Introduction Subclinical micronutrient deficiency in older adults is associated with chronic age-related diseases and adverse functional outcomes. In Germany, the older population is at-risk of insufficient micronutrient intake, but representative studies on micronutrient status in old and very old adults are scarce. This study's objectives were to estimate the prevalence of subclinical vitamin D, folate, vitamin B12 and iron deficiencies among older adults, aged 65 to 93, from the KORA-Age study in Augsburg, Germany (n = 1079), and to examine associated predictors. Methods Serum concentrations of 25-hydroxyvitamin D (25OHD), folate, vitamin B12, and iron were analyzed and compared to selected cut-offs for subclinical micronutrient deficiency. Associated predictors were investigated using multiple logistic regression analysis. Results The prevalence of subclinical vitamin D and vitamin B12 deficiencies were high, with 52.0% and 27.3% of individuals having low 25OHD ( Conclusion Subclinical micronutrient deficiency is a public health concern among KORA-Age participants, especially for vitamins D and B12. The predictors identified provide further rationale for screening high-risk subgroups and developing targeted public health interventions to tackle prevailing micronutrient inadequacies among older adults.

Evidence of a significant vitamin D deficiency among 9\u201313-year-old Polish children: results of a multicentre study

PurposeTo evaluate the extent to which the population of Polish preadolescents is vitamin D deficient and to assess seasonal variations in vitamin D status.Participants and methodsA total of 720 healthy children aged 9–13 years (409 girls, 311 boys) residing in 6 representative geographical locations in Poland were studied. A parental-assisted questionnaire provided data on nutritional habits, vitamin D supplements and sun exposure. Serum concentration of 25-hydroxyvitamin was determined twice, after the winter in March and after the summer in October.ResultsIn March, vitamin D deficiency (25–50 nmol/L) was found in 64%, and severe deficiency (< 25 nmol/L) in 20.2% of children. In October, the deficiency and severe deficiency were still noticed in 25.9 and 0.1% of children, respectively. The mean serum concentration of 25-OHD was 52% higher in October (55.4 ± 14.0 nmol/L) than in March (36.4 ± 13.5 nmol/L), (p < 0.01). In children with 25-OHD < 50 nmol/L in March, their 25-OHD concentration increased by 64% through March to October (32.5 ± 8.2 vs. 53.2 ± 7.9 nmol/L, p < 0.01). An association was found between 25-OHD concentration and regular consumption of vitamin D supplements, cod-liver oil and fish.ConclusionsThe majority of preadolescent Polish boys and girls show vitamin D deficiency after the winter period, although a distinct amelioration over summertime is found in this age group. There is a need to implement effective prevention and intervention strategies in the management of vitamin D deficiency among schoolchildren in Poland, with the supplementation throughout the entire year.

Indoor, outdoor, and night work and blood concentrations of vitamin D and parathyroid hormone.

Objectives The aim of this study was to examine blood concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) among indoor, outdoor, permanent and rotating night workers and the association with hours spent outdoors on and off work days. Methods Blood samples were collected from 425 workers (162 indoor, 112 outdoor, 118 rotating night and 33 permanent night workers) throughout all seasons. Serum concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) were analyzed by isotope dilution liquid chromatography-tandem mass spectrometry (LC MS/MS) and an automated immune analyzer, respectively. Personal light exposure levels were continuously recorded and used to estimate hours spent outdoors (all workers). Results Permanent night workers had 25.3% (95% CI 11.9-36.6) lower 25OHD concentration, 4.55 (95% CI 1.39-14.94) higher odds of vitamin D insufficiency (<50 nmol/L) and 14.5% [95% confidence interval (CI) 0.1-31.1] higher PTH concentration than indoor workers. Outdoor workers had similar 25OHD concentrations but 7.5% (95% CI -0.5-14.9) lower PTH concentration compared to indoor workers. Rotating night workers 25OHD and PTH concentrations did not differ from indoor workers. Concentration of 25OHD increased by 5.2% (95% CI 1.1-9.5) per hour spent outdoor at workdays in the summer. Conclusion Clinicians should be aware that vitamin D insufficiency may be more prevalent among permanent night workers and human resources should consider the positive effect of allowing workers to spend time outdoor during work hours.

Association between serum concentration of 25-hydroxyvitamin D [25(OH)D] and chronic periodontitis

Serum concentration of [25(OH)D] in Indonesia is at low level although Indonesia is one of Asia country which has a tropical climate. Vitamin D as an immunomodulatory agent invitro and in animal studies. However, data from clinical studies involvement vitamin D to chronic periodontitis are still controversy. The aim of this study was to evaluate the association between serum concentration of [25(OH)D] and chronic periodontitis. Totally 45 chronic periodontitis patients were analyzed. Spearman correlation models adjusted for subject and parameter included periodontal pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BOP) are analyzed. Totally 51.11% person have serum concentration of [25(OH)D] 21-50ng/mL were called insufficiency, and 15.56% is deficiency. Mean values of PPD >3mm indicating moderate criteria, CAL >4mm meaning severe criteria, and mean grade of BOP >2 degrees means the interdental papilla appears to be filled with little or much blood. Spearman correlation test results showed an inverse correlation between serum concentration of [25(OH)D] to the value of PPD, CAL, and BOP, however, was not statistically significant (r PPD -0.09; r CAL -0.118; r BOP 0.001, p>0.05). Insufficiency serum concentration of 25- hydroxyvitamin D [25(OH)D] was not associated significantly with PPD, CAL, and BOP of chronic periodontitis.

Markers of vitamin D metabolism and incidence of clinically diagnosed abdominal aortic aneurysm: The Atherosclerosis Risk in Communities Study.

Little is known about whether markers of vitamin D metabolism are associated with the development of abdominal aortic aneurysm (AAA), though these markers have been linked to other cardiovascular diseases. We tested the hypotheses that risk of AAA is higher among individuals with low serum concentrations of 25-hydroxy vitamin D [25(OH)D], and among those with elevated concentrations of calcium, fibroblast growth factor 23 (FGF23), phosphorus, and parathyroid hormone (PTH) using data from a cohort of black and white individuals with long-term follow-up. Markers of vitamin D metabolism were measured using serum collected in 1990-1992 from ARIC study participants (mean ± SD age 56.9 ± 5.7 years, 43.2% male, 23.9% black). A total of 12,770 participants were followed until 2011 for incident AAA. Multivariable-adjusted Cox regression models were used. A total of 449 incident AAA events occurred over a median follow-up of 19.7 years. For the association between serum calcium and risk of incident AAA there was evidence of interaction by sex ( p-interaction 0.02). Among women, in the fully adjusted model, the hazard ratio (95% confidence interval) comparing the highest to lowest quartile was 2.43 (1.25-4.73), whereas in men it was 1.01 (0.72-1.43). Not associated with risk of incident AAA were 25(OH)D, FGF23, phosphorus, and PTH. In this large prospective cohort, there was little evidence that markers of vitamin D metabolism are associated with risk of incident AAA. The positive association of calcium with AAA among women may warrant further investigation and replication in other populations.

Relationships of serum 25-hydroxyvitamin D, ionized calcium and parathyroid hormone after obesity surgery.

The high prevalence of secondary hyperparathyroidism (SHPT) after obesity surgery is a concern for long-term bone health. Limited knowledge exists about optimal vitamin D and suppression of parathyroid hormone (PTH) after these procedures. The aim of this study was to investigate the prevalence of SHPT and its relation to vitamin D status. A cross-sectional study at Oslo University Hospital, Norway. A total of 502 consecutive patients, age 22-64years, attending 2-year follow-up after Roux-en-Y gastric bypass. A serum intact PTH >7.0pmol/L in the absence of elevated serum ionized calcium (iCa) was considered as SHPT. Vitamin D status was defined by serum concentrations of 25-hydroxyvitamin D (S-25(OH)D). Altogether, 171 patients (34%) had SHPT. The prevalence of SHPT varied across the range of S-25(OH)D (P<0.001), being highest (71%) with S-25(OH)D<25nmol/L. Compared with S-25(OH)D<50nmol/L, the prevalence of SHPT was lower with S-25(OH)D≥50nmol/L (29.0%; RR=0.64 (95%-CI:0.50-0.81)) and S-25(OH)D≥75nmol/L (27.7%; RR=0.61 (95%-CI:0.44-0.84)). S-25(OH)D≥ 100nmol/L was associated with the lowest PTH and the lowest prevalence of SHPT (16.0%; RR=0.35 (95%-CI:0.14-0.88) compared with S-25(OH)D<50nmol/L) and the most normal calcium distribution. These associations were most pronounced with iCa in the lower range. A synergistic association was found for S-25(OH)D and iCa on SHPT. Vitamin D deficient patients had the highest prevalence of SHPT 2years after gastric bypass. PTH and the prevalence of SHPT were notably lower with S-25(OH)D≥100nmol/L, compared with lower target levels.

Pathophysiology of Osgood-Schlatter Disease: Does Vitamin D have a Role?

Objective: The objectives of this study were to determine the vitamin D status in a sample of Tunisian children with Osgood-Schlatter disease (OSD).Patients and methods: We performed a prospective study including normal and healthy children presented with OSD. An assessment of the status of vitamin D measuring serum concentrations of 25-hydroxy vitamin D, was done for all patients using the chemiluminescence immunoassays technique.Results: During the study period, 80 children have been enrolled and the mean age was 13.6 years. All children had low-level vitamin D with a mean of 19.2 ng/mL (range of 5-27 ng/mL). All the children were then placed under a vitamin D substitution. At follow-up, majority of knees were asymptomatic and functioned unaltered with all activities. Radiologically, all patients showed healing of the tibial tuberosity secondary ossification center.Conclusion: In our study, all children with OSD had low-level vitamin D and after supplementation of vitamin D, the symptoms were resolved. Vitamin D deficiency screening should be instituted among children at risk of OSD and early vitamin D supplementation should be started for prevention.

Vitamin D status in patients with type-2 diabetes mellitus in Riyadh City, Saudi Arabia

Background Type-2 diabetes mellitus (T2DM) is a progressive and chronic disease characterized by both β-cell dysfunction and increased insulin resistance. Vitamin D is a crucial factor in the development of T2DM because it is necessary for normal insulin secretion. Despite ample sunshine, vitamin D deficiency is common in the Middle East. Objective To report the vitamin D status and its impact on the people in Riyadh City, Saudi Arabia, with T2DM. Patients and methods The study was carried out on 100 patients of 31–79 years old with T2DM. According to their vitamin D status, they were classified into three groups: group 1 (deficient, vitamin D: 30 ng/ml). All were subjected to history taking, clinical examination, and assessment of fasting blood samples of serum concentrations of 25-hydroxy vitamin D [s-25(OH)D], blood glucose, glycated hemoglobin, lipid profile, liver enzymes (alanine transaminase and aspartate transaminase), urea and creatinine. Results Inadequate vitamin D level was observed in 80% of the participants, with a mean s-25(OH)D of 18.3±10.9 ng/ml. S-25(OH)D correlated negatively with fasting blood sugar (FBS) (P=0.008), with cholesterol and low-density lipoprotein (P=0.012 and 0.003, respectively). The low vitamin D status was strongly associated with poor glycemic control (P=0.001) and in females (P=0.002). There was no significant association between s-25(OH)D level and different age groups. Conclusion There is an overwhelming prevalence of vitamin D deficiency in our sample of Saudi diabetic patients. Association of low vitamin D status with poor glycemic control and atherogenic lipid profile suggests a role of vitamin D in the control of T2DM and dyslipidemia and the importance of early detection of its deficiency and vitamin D supplementation.

Serum Concentrations of 25-Hydroxyvitamin D and Depression in a General Middle-Aged to Elderly Population in Finland.

Low concentrations of serum 25-hydroxyvitamin D [25(OH)D] have been postulated to associate with an increased prevalence of depression. As there are a limited number of publications on this issue, we examined the association between serum 25(OH)D and depression in a general middle-aged or older population. A population-based cross-sectional study. A total of 1602 men and women from the population-based Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) in Eastern Finland, aged 53-73 y in 1998-2001, were analysed. Depressive symptoms were assessed with the DSM-III depression scale, and those individuals who had scores over 4 (range 0-12) or had reported undergoing current antidepressant therapy, were considered as suffering from depression. Associations were estimated in serum 25(OH)D tertiles using logistic regression. Among the participants, 183 subjects (11.4%) were considered to have depression. The mean age of the subjects was 62.6 years (SD 6.4, range 53.4-73.8 years). The mean serum 25(OH)D concentration was 43.8 nmol/L (SD 17.7, range 8.5-112.8 nmol/L), concentrations <50 nmol/L were observed in 65.0% of the subjects, and only 5.0% displayed concentrations ≥75 nmol/L. After multivariable adjustments, the odds ratios for having depression in the tertiles (from highest to the lowest) of serum 25(OH)D were 1, 1.35 (95 % CI: 0.87, 2.09) and 1.64 (95 % CI: 1.03, 2.59), P for trend=0.036. These findings indicate that a lower concentration of serum 25(OH)D is associated with a higher prevalence of depression in an elderly general population.

Effects of Low-Dose Dairy Protein Plus Micronutrient Supplementation during Resistance Exercise on Muscle Mass and Physical Performance in Older Adults: A Randomized, Controlled Trial.

To investigate whether supplementation with low-dose dairy protein plus micronutrients augments the effects of resistance exercise (RE) on muscle mass and physical performance compared with RE alone among older adults. Randomized controlled trial. Tokyo, Japan. Eighty-two community-dwelling older adults (mean age, 73.5 years) were randomly allocated to an RE plus dairy protein and micronutrient supplementation group or an RE only group (n = 41 each). The RE plus supplementation group participants ingested supplements with dairy protein (10.5 g/day) and micronutrients (8.0 mg zinc, 12 μg vitamin B12, 200 μg folic acid, 200 IU vitamin D, and others/day). Both groups performed the same twice-weekly RE program for 12 weeks. Whole-body, appendicular, and leg lean soft-tissue mass (WBLM, ALM, and LLM, respectively) with dual-energy X-ray absorptiometry, physical performance, biochemical characteristics, nutritional intake, and physical activity were measured before and after the intervention. Data were analyzed by using linear mixed-effects models. The groups exhibited similar significant improvements in maximum gait speed, Timed Up-and-Go, and 5-repetition and 30-s chair stand tests. As compared with RE only, RE plus supplementation significantly increased WBLM (0.63 kg, 95% confidence interval [CI]: 0.31-0.95), ALM (0.37 kg, 95% CI: 0.16-0.58), LLM (0.27 kg, 95% CI: 0.10-0.46), and serum concentrations of 25-hydroxyvitamin D (4.7 ng/mL, 95% CI: 1.6-7.9), vitamin B12 (72.4 pg/mL, 95% CI: 12.9-131.9), and folic acid (12.9 ng/mL, 95% CI: 10.3-15.5) (all P < 0.05 for group-by-time interactions). Changes over time in physical activity and nutritional intake excluding the supplemented nutrients were similar between groups. Low-dose dairy protein plus micronutrient supplementation during RE significantly increased muscle mass in older adults but did not further improve physical performance.

Obesity is associated with vitamin D deficiency in Danish children and adolescents.

Sufficient serum concentrations of vitamin D are required to maintain bone health during growth. The aims of this study were to determine whether vitamin D deficiency is more prevalent among children and adolescents with obesity compared to their normal weight peers and to identify clinical and biochemical variables associated with vitamin D deficiency. One thousand four hundred and eighty-four children and adolescents with overweight/obesity and 2143 population-based controls were recruited from the Danish Childhood Obesity Biobank. Anthropometric variables and fasting concentrations of serum 25-hydroxy vitamin D (25-OH-D), plasma parathyroid hormone (PTH), calcium and phosphate were assessed at baseline. Vitamin D deficiency was defined as serum 25-OH-D concentrations <30 nmol/L. Linear and logistic regressions were used to identify variables associated with vitamin D deficiency. A total of 16.5% of the children and adolescents with obesity (body mass index [BMI] standard deviation score [SDS]>2.33) exhibited vitamin D deficiency, with an odds ratio (OR) 3.41 (confidence interval [CI]: 2.27-5.71; p<0.0001) for being vitamin D deficient compared to their normal weight peers. BMI-SDS was independently and inversely associated with serum 25-OH-D concentrations. Other independent risk factors for vitamin D deficiency were being older than 14 years (OR: 2.39; CI: 1.28-4.48; p=0.006), more than 4 daily hours of screen time (OR: 4.56; CI: 2.59-8.05; p<0.0001) and blood sample assessment during winter-spring (OR: 6.44; CI: 4.47-9.26; p<0.0001). Vitamin D deficiency was common among Danish children and adolescents with obesity. The degree of obesity was independently associated with lower serum 25-OH-D concentrations.

Vitamin D supplementation during pregnancy: state of the evidence from a systematic review of randomised trials

Objectives To estimate the effects of vitamin D supplementation during pregnancy on 11 maternal and 27 neonatal/infant outcomes; to determine frequencies at which trial outcome data were missing, unreported, or...

Prevalence and Predictors of Subclinical Micronutrient Deficiency in German Older Adults: Results from the Population-Based KORA-Age Study.

Subclinical micronutrient deficiency in older adults is associated with chronic age-related diseases and adverse functional outcomes. In Germany, the older population is at risk of insufficient micronutrient intake, but representative studies on micronutrient status in old and very old adults are scarce. This study’s objectives were to estimate the prevalence of subclinical vitamin D, folate, vitamin B12 and iron deficiencies among older adults, aged 65 to 93, from the KORA-Age study in Augsburg, Germany (n = 1079), and to examine associated predictors, using multiple logistic regression. Serum concentrations of 25-hydroxyvitamin D (25OHD), folate, vitamin B12, and iron were analyzed. The prevalence of subclinical vitamin D and vitamin B12 deficiencies were high, with 52.0% and 27.3% of individuals having low 25OHD (<50 nmol/L) and low vitamin B12 concentrations (<221 pmol/L), respectively. Furthermore, 11.0% had low iron (men <11.6 µmol/L, women <9.0 µmol/L) and 8.7% had low folate levels (<13.6 nmol/L). Common predictors associated with subclinical micronutrient deficiency included very old age, physical inactivity, frailty and no/irregular use of supplements. Subclinical micronutrient deficiency is a public health concern among KORA-Age participants, especially for vitamins D and B12. The predictors identified provide further rationale for screening high-risk subgroups and developing targeted public health interventions to tackle prevailing micronutrient inadequacies among older adults.

Overweight and obesity are associated with lower vitamin D status in Canadian children and adolescents.

There is evidence that 25-hydroxyvitamin D levels are lower in overweight and obese youth. This study examined the relationship between weight status and 25-hydroxyvitamin D, while controlling for confounders, in Canadian youth. Plasma 25-hydroxyvitamin D from subjects aged 6 to 17 years from the Canadian Health Measures Survey cycles 1 (2007 to 2009) and 2 (2009 to 2011) was used. Sex-specific multiple linear regression and logistic regressions examined the relationship of overweight and obesity (body mass index ≥ 85th percentile) with 25-hydroxyvitamin D levels and the odds of 25-hydroxyvitamin D <40 nmol/L and <50 nmol/L. The prevalence of risk of vitamin D deficiency (25-hydroxyvitamin D < 30 nmol/L) was 6% (95% confidence interval [CI] 3.26% to 10.12%). Vitamin D inadequacy, estimated by levels <40 nmol/L, was 15% (95% CI 10.34% to 20.39%; 19% [95% CI 13.1 to 25.6] for teenagers). Seventy per cent (95% CI 63.59 to 75.17) had levels >50 nmol/L, consistent with achieving the Recommended Dietary Allowance. In adjusted analyses, overweight/obesity (1/3 of subjects) was independently associated with lower 25-hydroxyvitamin D for both sexes after adjustment for age, race, income, season, vitamin D supplementation and daily milk consumption. For 25-hydroxyvitamin D <40 nmol/L, the overweight/obese odds ratio for males was 2.63 (95% CI 1.34 to 5.18). For 25-hydroxyvitamin D <50 nmol/L, overweight/obese odds ratios were 2.19 (95% CI 1.46 to 3.28) for males and 1.39 (95% CI 1.05 to 1.84) for females. This study confirms the inverse association between adiposity and serum concentrations of 25-hydroxyvitamin D in Canadian youth and the independent association of overweight/obesity to 25-hydroxyvitamin D level and vitamin D status after adjustment for other factors.

Association between serum concentration of 25-hydroxyvitamin D and community-acquired pneumonia: a case-control study.

BackgroundCommunity-acquired pneumonia (CAP) is a common disease with significant morbidity and mortality. There is evidence that vitamin D deficiency can be associated with infectious diseases. The aim of this study was to compare the levels of vitamin D between patients with CAP and healthy controls.MethodsIn a case-control study on 73 patients with CAP and 76 healthy controls, the serum concentration of 25-hydroxyvitamin D (25[OH]D) was measured. Severity and outcomes of disease and also duration of hospital stay were compared in patients with different levels of 25(OH)D. The severity of CAP was assessed using the CURB-65 score (confusion, uremia, respiratory rate, low blood pressure, age ≥65 years) and was also reflected by the length of hospital stay, admission to intensive care unit (ICU), and 30-day mortality.ResultsIn total, 81.2% of the study population had vitamin D levels <30 ng/dL. The risk of pneumonia among subjects with deficient vitamin D levels was 3.69 (95% CI: 1.46, 9.31) times of those with sufficient vitamin D level (P=0.006). Prevalence of severe deficiency of vitamin D in scores three and four of CURB-65 (59.38%), was far more than scores one and two (31.71%). Also, results indicated patients with severe deficiency had a higher risk for ICU admission, 30-day mortality, and longer hospitalization stay, but these were not statistically significant.ConclusionAccording to findings, a low level of 25(OH)D is associated with a higher incidence of CAP and more severe disease. It is recommended to pay more attention to vitamin D deficiency in infectious diseases, particularly in CAP patients.

Vitamin D status of gastrostomy-fed children with special needs: a cross-sectional pilot study.

To assess the vitamin D status of gastrostomy-fed children. Vitamin D status was measured in 32 children aged five to 16 years recruited from special schools in Manchester, UK (53° 48' N). All children were receiving a nutritionally complete, commercially prepared enteral feed via gastrostomy, and had been established on this regimen for over 12 months. Serum concentrations of 25-hydroxyvitamin D (25OHD) were measured at the end of winter. Children with serum concentrations of 25OHD >50 nmol/L were considered to be sufficient, and those with concentrations <25 nmol/L were considered to be deficient. Approximately 83% of subjects had sufficient concentrations of serum 25OHD (>50 nmol/L). One subject was vitamin D deficient (serum 25OHD <25 nmol/L), and four were vitamin D insufficient (serum 25OHD >25 nmol/L - <50 nmol/L). The median vitamin D derived from enteral feeds was 9.45 μg/day; range 3.5-30; 13 children (41%) received less than 10 μg of vitamin D per day from their enteral feed. Nutritionally complete gastrostomy feeds may be protective against vitamin D deficiency in the majority of children with special needs. We recommend that all children over 1 year of age receive 10 μg (400 IU) of vitamin D, as recommended by the Scientific Advisory Committee on Nutrition (SACN).

Vitamin D Supplementation Trials Aimed at Reducing Mortality Have Much Higher Power When Focusing on People with Low Serum 25-Hydroxyvitamin D Concentrations

Background: Evidence of an inverse association between serum vitamin D and mortality from epidemiological studies has prompted efforts to reduce mortality by vitamin D supplementation, either in targeted interventions for people with vitamin D insufficiency or deficiency, or in untargeted interventions regardless of baseline vitamin D status.Objective: We aimed to assess the expected impact of the 2 different approaches on effect sizes and power of intervention studies.Methods: Serum concentrations of 25-hydroxyvitamin D [25(OH)D] were measured in 9579 participants aged 50-75 y in the German Epidemiologische Studie zu Chancen der Verhütung, Früherkennung und optimierten Therapie chronischer Erkrankungen in der älteren Bevölkerung (ESTHER) study who were followed for mortality for a median of 12.4 y. We estimated adjusted HRs of mortality from all causes, cardiovascular disease, and cancer for defined increases in serum 25(OH)D by Cox regression, both across the full range of 25(OH)D concentrations and for those with vitamin D insufficiency [30 nmol/L ≤ 25(OH)D < 50 nmol/L] or deficiency [25(OH)D <30 nmol/L] only, and we calculated the power of intervention studies achieving those effect sizes.Results: An inverse association between serum 25(OH)D and mortality was observed only for participants with vitamin D insufficiency or deficiency and was strongest for the latter. Accordingly, the expected effects were much stronger and the expected power was much higher for interventions that targeted these groups than for untargeted interventions. For example, a targeted intervention study with 10,000 older adults (age 50-75 y) with serum 25(OH)D <50 nmol/L that increases serum 25(OH)D concentrations by 20 nmol/L in the intervention group (n = 5000) would be expected to yield a 26% reduction of all-cause mortality that could be detected with 89% power within 5 y of follow-up compared with a 10% mortality reduction and 20% power in an untargeted intervention study of the same size.Conclusions: Vitamin D supplementation trials aimed at reducing mortality in older adults have much higher power when focused on those with low serum 25(OH)D concentrations.