Clinical Guidelines for Management of Bone Health in Rett Syndrome Based on Expert Consensus and Available Evidence

Objectives

We developed clinical guidelines for the management of bone health in Rett syndrome through evidence review and the consensus of an expert panel of clinicians.

Methods

An initial guidelines draft was created which included statements based upon literature review and 11 open-ended questions where literature was lacking. The international expert panel reviewed the draft online using a 2-stage Delphi process to reach consensus agreement. Items describe the clinical assessment of bone health, bone mineral density assessment and technique, and pharmacological and non-pharmacological interventions.

Results

Agreement was reached on 39 statements which were formulated from 41 statements and 11 questions. When assessing bone health in Rett syndrome a comprehensive assessment of fracture history, mutation type, prescribed medication, pubertal development, mobility level, dietary intake and biochemical bone markers is recommended. A baseline densitometry assessment should be performed with accommodations made for size, with the frequency of surveillance determined according to individual risk. Lateral spine x-rays are also suggested. Increasing physical activity and initiating calcium and vitamin D supplementation when low are the first approaches to optimizing bone health in Rett syndrome. If individuals with Rett syndrome meet the ISCD criterion for osteoporosis in children, the use of bisphosphonates is recommended.

Conclusion

A clinically significant history of fracture in combination with low bone densitometry findings is necessary for a diagnosis of osteoporosis. These evidence and consensus-based guidelines have the potential to improve bone health in those with Rett syndrome, reduce the frequency of fractures, and stimulate further research that aims to ameliorate the impacts of this serious comorbidity.     

Vitamin D Deficiency in Early Pregnancy

Objective

Vitamin D deficiency is a common problem in reproductive-aged women in the United States. The effect of vitamin D deficiency in pregnancy is unknown, but has been associated with adverse pregnancy outcomes. The objective of this study was to analyze the relationship between vitamin D deficiency in the first trimester and subsequent clinical outcomes.

Study Design

This is a retrospective cohort study. Plasma was collected in the first trimester from 310 nulliparous women with singleton gestations without significant medical problems. Competitive enzymatic vitamin D assays were performed on banked plasma specimens and pregnancy outcomes were collected after delivery. Logistic regression was performed on patients stratified by plasma vitamin D concentration and the following combined clinical outcomes: preeclampsia, preterm delivery, intrauterine growth restriction, gestational diabetes, and spontaneous abortion.

Results

Vitamin D concentrations were obtained from 235 patients (mean age 24.3 years, range 18-40 years). Seventy percent of our study population was vitamin D insufficient with a serum concentration less than 30 ng/mL (mean serum concentration 27.6 ng/mL, range 13-71.6 ng/mL). Logistic regression was performed adjusting for age, race, body mass index, tobacco use, and time of year. Adverse pregnancy outcomes included preeclampsia, growth restriction, preterm delivery, gestational diabetes, and spontaneous abortion. There was no association between vitamin D deficiency and composite adverse pregnancy outcomes with an adjusted odds ratio of 1.01 (p value 0.738, 95% confidence intervals 0.961-1.057).

Conclusion

Vitamin D deficiency did not associate with adverse pregnancy outcomes in this study population. However, the high percentage of affected individuals highlights the prevalence of vitamin D deficiency in young, reproductive-aged women.     

Concordance of Results from Randomized and Observational Analyses within the Same Study: A Re-Analysis of the Women’s Health Initiative Limited-Access Dataset

Background

Observational studies (OS) and randomized controlled trials (RCTs) often report discordant results. In the Women’s Health Initiative Calcium and Vitamin D (WHI CaD) RCT, women were randomly assigned to CaD or placebo, but were permitted to use personal calcium and vitamin D supplements, creating a unique opportunity to compare results from randomized and observational analyses within the same study.

Methods

WHI CaD was a 7-year RCT of 1g calcium/400IU vitamin D daily in 36,282 post-menopausal women. We assessed the effects of CaD on cardiovascular events, death, cancer and fracture in a randomized design- comparing CaD with placebo in 43% of women not using personal calcium or vitamin D supplements- and in a observational design- comparing women in the placebo group (44%) using personal calcium and vitamin D supplements with non-users. Incidence was assessed using Cox proportional hazards models, and results from the two study designs deemed concordant if the absolute difference in hazard ratios was ≤0.15. We also compared results from WHI CaD to those from the WHI Observational Study(WHI OS), which used similar methodology for analyses and recruited from the same population.

Results

In WHI CaD, for myocardial infarction and stroke, results of unadjusted and 6/8 covariate-controlled observational analyses (age-adjusted, multivariate-adjusted, propensity-adjusted, propensity-matched) were not concordant with the randomized design results. For death, hip and total fracture, colorectal and total cancer, unadjusted and covariate-controlled observational results were concordant with randomized results. For breast cancer, unadjusted and age-adjusted observational results were concordant with randomized results, but only 1/3 other covariate-controlled observational results were concordant with randomized results. Multivariate-adjusted results from WHI OS were concordant with randomized WHI CaD results for only 4/8 endpoints.

Conclusions

Results of randomized analyses in WHI CaD were concordant with observational analyses for 5/8 endpoints in WHI CaD and 4/8 endpoints in WHI OS.     

The Prevalence of Vitamin D Deficiency among Cancer Survivors in a Nationwide Survey of the Korean Population

Background

Recent studies have shown that inadequate vitamin D levels are associated with a poor cancer prognosis, but data regarding actual vitamin D levels in cancer survivors are limited. This study investigated the vitamin D levels and prevalence of vitamin D deficiency among Korean cancer survivors compared with non-cancer controls, and identified the factors associated with vitamin D deficiency.

Methods

Using the Korea National Health and Nutrition Examination Survey (KNHANES), 915 cancer survivors and 29,694 controls without a history of cancer were selected. Serum 25(OH)D levels were measured; vitamin D deficiency was defined as 25(OH)D levels less than 20 ng/mL. Chi-square tests and multiple logistic regression analyses were used to evaluate the prevalence of vitamin D deficiency and associated factors.

Results

Vitamin D deficiency was observed in 62.7% of cancer survivors and 67.1% of controls. Among cancer survivors, vitamin D deficiency was most prevalent among 19–44 year olds (76.2%) and among managers, professionals, and related workers (79.3%). Multiple logistic regression analysis revealed that younger cancer survivors and those who work indoors were predisposed to vitamin D deficiency.

Conclusion

Vitamin D deficiency was prevalent among both cancer survivors and controls in Korea. The regular evaluation and management of vitamin D levels is needed for both bone health and general health in cancer survivors.     

Vitamin D Supplementation for Childhood Asthma: A Systematic Review and Meta-Analysis

Importance

There is growing evidence that vitamin D plays a role in the pathogenesis of asthma but it is unclear whether supplementation during childhood may improve asthma outcomes.

Objectives

The objective of this systematic review and meta-analysis was to evaluate the efficacy and safety of vitamin D supplementation as a treatment or adjunct treatment for asthma.

Data Sources

We searched MEDLINE, Embase, CENTRAL, and CINAHL through July 2014.

Study Selection

We included RCTs that evaluated vitamin D supplementation in children versus active control or placebo for asthma.

Data Extraction and Synthesis

One reviewer extracted data and one reviewer verified data accuracy. We qualitatively summarized the main results of efficacy and safety and meta-analyzed data on comparable outcomes across studies. We used GRADE for strength of evidence.

Main Outcome Measures

Main planned outcomes measures were ED visits and hospitalizations. As secondary outcomes, we examined measures of asthma control, including frequency of asthma exacerbations, asthma symptom scores, measures of lung function, β₂-agonist use and daily steroid use, adverse events and 25-hydroxyvitamin D levels.

Results

Eight RCTs (one parallel, one crossover design) comprising 573 children aged 3 to 18 years were included. One study (moderate-quality, n = 100) reported significantly less ED visits for children treated with vitamin D. No other studies examined the primary outcome (ED visits and hospitalizations). There was a reduced risk of asthma exacerbations in children receiving vitamin D (low-quality; RR 0.41, 95% CI 0.27 to 0.63, 3 studies, n = 378). There was no significant effect for asthma symptom scores and lung function. The serum 25(OH)D level was higher in the vitamin D group at the end of the intervention (low-quality; MD 19.66 nmol/L, 95% CI 5.96 nmol/L to 33.37 nmol/L, 5 studies, n = 167).

Limitations

We identified a high degree of clinical diversity (interventions and outcomes) and methodological heterogeneity (sample size and risk of bias) in included trials.

Conclusions and Relevance

Randomized controlled trials provide some low-quality evidence to support vitamin D supplementation for the reduction of asthma exacerbations. Evidence on the benefits of vitamin D supplementation for other asthma-related outcomes in children is either limited or inconclusive. We recommend that future trials focus on patient-relevant outcomes that are comparable across studies, including standardized definitions of asthma exacerbations.     

Vitamin D Status at Birth and Future Risk of Attention Deficit/Hyperactivity Disorder (ADHD)

Objective

To investigate whether children with Attention Deficit/Hyperactivity Disorder have lower levels of Vitamin D₃ at birth than matched controls.

Material

Umbilical cord blood samples collected at birth from 202 children later diagnosed with Attention Deficit/Hyperactivity Disorder were analysed for vitamin D content and compared with 202 matched controls. 25-OH vitamin D₃ was analysed by liquid chromatography tandem mass spectrometry.

Results

No differences in cord blood vitamin D concentration were found between children with Attention Deficit/Hyperactivity Disorder (median 13.0 ng/ml) and controls (median 13.5 ng/ml) (p = 0.43). In a logistic regression analysis, Attention Deficit/Hyperactivity Disorder showed a significant association with maternal age (odds ratio: 0.96, 95% confidence interval: 0.92–0.99) but not with vitamin D levels (odds ratio: 0.99, 95% confidence interval: 0.97–1.02).

Conclusion

We found no difference in intrauterine vitamin D levels between children later developing Attention Deficit/Hyperactivity Disorder and matched control children. However, the statistical power of the study was too weak to detect an eventual small to medium size association between vitamin D levels and Attention Deficit/Hyperactivity Disorder.     

Bone fragility in sarcoidosis and relationships with calcium metabolism disorders: a cross sectional study on 142 patients

Introduction

The prevention of fragility fractures in patients with sarcoidosis is a serious concern and the potential risk of hypercalcemia limits vitamin D and calcium supplementation. The objective of this study was to evaluate the risk factors for low bone mineral density (BMD) and fractures in sarcoidosis. In particular, we aimed to determine the link among bone fragility and calcium and vitamin D metabolism in this population.

Methods

We performed a cross-sectional analysis on 142 consecutive patients with histologically proven sarcoidosis. BMD and prevalence of vertebral fractures on X-rays were assessed and the association with potential risk factors was studied by regression analysis.

Results

Fragility fractures occurred in 23.5% of patients, despite a normal mean BMD in the study population. In a multivariate analysis, low dietary calcium, fracture, age, gender and menopause were associated with increased risk of low BMD. Low dietary calcium, high current corticosteroid dose and low creatinine clearance were associated with increased risk of fracture. Serum 25(OH)D between 10 and 20 ng/ml was significantly associated with higher BMD. Conversely, values greater than 20 ng/ml were associated with increased risk of fracture. Serum 25(OH)D level was inversely correlated with disease activity. Of note, vitamin D supplements increased serum 25(OH)D in a dose-dependent manner but had no effect on serum calcium level.

Conclusions

Sarcoidosis patients have a high risk of fracture despite not having a lowered BMD suggesting that other independent factors are involved. Current corticosteroid dose, low dietary calcium and serum 25(OH)D levels are associated with bone fragility. In sarcoidosis, calcium and vitamin D supplementation might be warranted, but desirable 25(OH)D serum levels might be lower than those advised for the general population.     

Risk Factors for Vitamin D Deficiency among Veterans with and without HIV Infection

Objectives

We aimed to describe and compare the prevalence of vitamin D deficiency between HIV-negative and HIV-infected veterans in the southern United States, and to determine risk factors for vitamin D deficiency for HIV infected patients.

Methods

Cross-sectional, retrospective study including all patients followed at the Atlanta VA Medical Center with the first 25-hydroxyvitamin D [25(OH)D] level determined between January 2007 and August 2010. Multivariate logistic regression analysis was used to determine risk factors associated with vitamin D deficiency (< 20 ng/ml).

Results

There was higher prevalence of 25(OH)D deficiency among HIV-positive compared to HIV-negative patients (53.2 vs. 38.5%, p <0.001). Independent risk factors for vitamin D deficiency in HIV + patients included black race (OR 3.24, 95% CI 2.28–4.60), winter season (OR 1.39, 95% CI 1.05–1.84) and higher GFR (OR 1.01, CI 1.00–1.01); increasing age (OR 0.98, 95% CI 0.95–0.98), and tenofovir use (OR 0.72, 95% CI 0.54–0.96) were associated with less vitamin D deficiency.

Conclusions

Vitamin D deficiency is a prevalent problem that varies inversely with age and affects HIV-infected patients more than other veterans in care. In addition to age, tenofovir and kidney disease seem to confer a protective effect from vitamin D deficiency in HIV-positive patients.     

Red Blood Cell Fatty Acids and Incident Diabetes Mellitus in the Women’s Health Initiative Memory Study

Context

The relations between dietary and/or circulating levels of fatty acids and the development of type 2 diabetes is unclear. Protective associations with the marine omega-3 fatty acids and linoleic acid, and with a marker of fatty acid desaturase activity delta-5 desaturase (D5D ratio) have been reported, as have adverse relations with saturated fatty acids and D6D ratio.

Objective

To determine the associations between red blood cell (RBC) fatty acid distributions and incident type 2 diabetes.

Design

Prospective observational cohort study nested in the Women’s Health Initiative Memory Study.

Setting

General population.

Subjects

Postmenopausal women.

Main Outcome Measures

Self-reported incident type 2 diabetes.

Results

There were 703 new cases of type 2 diabetes over 11 years of follow up among 6379 postmenopausal women. In the fully adjusted models, baseline RBC D5D ratio was inversely associated with incident type 2 diabetes [Hazard Ratio (HR) 0.88, 95% confidence interval (CI) 0.81–0.95) per 1 SD increase. Similarly, baseline RBC D6D ratio and palmitic acid were directly associated with incident type 2 diabetes (HR 1.14, 95% CI 1.04–1.25; and HR 1.24, 95% CI 1.14–1.35, respectively). None of these relations were materially altered by excluding incident cases in the first two years of follow-up. There were no significant relations with eicosapentaenoic, docosahexaenoic or linoleic acids.

Conclusions

Whether altered fatty acid desaturase activities or palmitic acid levels are causally related to the development of type 2 diabetes cannot be determined from this study, but our findings suggest that proportions of certain fatty acids in RBC membranes are associated with risk for type 2 diabetes.     

Vitamin D Deficiency and Insufficiency in Hospitalized COPD Patients

Introduction

31–77% of patients with COPD have vitamin D deficiency and insufficiency, with results being highly variable between studies. Vitamin D may also correlate with disease characteristics.

Aim

To find out the prevalence of vitamin D deficiency and insufficiency in patients with COPD admitted for exacerbation and a risk factors for lower vitamin D levels among comorbidities and COPD characteristics.

Methods

152 patients were studied for vitamin D serum levels (25(OH)D). All of them were also assessed for diabetes mellitus (DM) and metabolic syndrome (MS). Data were gathered also for smoking status and exacerbations in last year. All patients completed CAT and mMRC questionnaires and underwent spirometry.

Results

A total of 83,6% of patients have reduced levels of vitamin D. 42,8% (65/152) have vitamin D insufficiency (defined as 25–50 nmol/L) and 40,8% (62/152) have vitamin D deficiency (<25 nmol/L). The mean level of 25(OH)D for all patients is 31,97 nmol/L (95%CI 29,12–34,68). Vitamin D deficiency and insufficiency are more prevalent in females vs. males (97,7 vs 77,8%; p = 0.003). The prevalence and severity of vitamin D deficiency and insufficiency in this study is significantly higher when compared to an unselected Bulgarian population (prevalence 75,8%; mean level 38,75 nmol/L). Vitamin D levels correlate with quality of life (measured by the mMRC scale) and lung function (FVC, FEV1, FEV6, FEF2575, FEV3, but not with FEV1/FVC ratio and PEF), it does not correlate with the presence of arterial hypertension, DM, MS and number of moderate, severe and total exacerbations. Vitamin D deficiency is a risk factor for longer hospital stay.

Conclusions

The patients with COPD admitted for exacerbation are a risk group for vitamin D deficiency and insufficiency, which is associated with worse disease characteristics.     

Prevalence of Sarcopenia and Its Relationship with Sites of Fragility Fractures in Elderly Chinese Men and Women

Objective

Sarcopenia might be associated with bone fragility in elderly individuals. This study aimed to investigate the prevalence of sarcopenia and its association with fragility fracture sites in elderly Chinese patients.

Methods

Patients (322 men and 435 women) aged 65–94 years and with a history of fragility fractures in the ankle, wrist, vertebrae or hip, and healthy men (n = 1263) and women (n = 1057) aged 65–92 years without a history of fractures were enrolled. Whole-body dual energy X-ray absorptiometry was used to analyze skeletal muscle mass index (SMI), fat mass and bone mineral density. Sarcopenia was defined as SMI less than two standard deviations below the mean of a young reference group.

Results

Sarcopenia occurrence varied with fracture location. Sarcopenia was more common in females with vertebral and hip fractures and in men with hip and ankle fractures than in the non-fracture group). Sarcopenia was significantly more prevalent in men with wrist, hip and ankle fractures than in women. SMI was correlated with BMD in different fracture groups. Logistic regression analyses revealed that lower SMI was associated with an increased risk of hip fracture both in men and women and ankle fracture in men.

Discussion

Sarcopenia may be an independent risk factor for hip and ankle fractures in men, and for hip fractures in women.     

Cassava Intake and Vitamin A Status among Women and Preschool Children in Akwa-Ibom,Nigeria

Background

As part of the HarvestPlus provitamin A-biofortified cassava program in Nigeria we conducted a survey to determine the cassava intake and prevalence of vitamin A deficiency among children 6-59 months and women of childbearing age in the state of Akwa Ibom.

Methods

A cluster-randomized cross-sectional survey was conducted in 2011 in Akwa Ibom, Nigeria. The usual food and nutrient intakes were estimated using a multi-pass 24-hour recall with repeated recall on a subsample. Blood samples of children and women were collected to analyze for serum retinol, serum ferritin, and acute phase proteins as indicators of infection. Vitamin A deficiency was defined as serum retinol <0.70 μmol/L adjusted for infection.

Results

A total of 587 households of a mother-child dyad participated in the dietary intake assessment. Cassava was very widely consumed in Akwa Ibom, mainly as gari or foofoo. Daily cassava consumption frequency was 92% and 95% among children and women, respectively. Mean (±SD) cassava intake (expressed as raw fresh weight) was 348 ± 317 grams/day among children and 940 ± 777 grams/day among women. Intakes of most micronutrients appeared to be adequate with the exception of calcium. Median vitamin A intake was very high both for children (1038 μg RAE/day) and women (2441 μg RAE/day). Red palm oil and dark green leafy vegetables were the main sources of vitamin A in the diet, with red palm oil alone contributing almost 60% of vitamin A intake in women and children. Prevalence of vitamin A deficiency ranged from moderate (16.9 %) among children to virtually non-existent (3.4 %) among women.

Conclusion

Consumption of cassava and vitamin A intake was high among women and children in Akwa Ibom with a prevalence of vitamin A deficiency ranging from moderate in children to non-existent among women. The provitamin A biofortified cassava and other vitamin A interventions should focus dissemination in states where red palm oil is not widely consumed.     

The Association between Pre-Treatment Serum 25-Hydroxyvitamin D and Survival in Newly Diagnosed Stage IV Prostate Cancer

Background/Aims

Emerging evidence in the literature suggests a positive association between serum 25-hydroxyvitamin D [25(OH)D], a standard indicator of vitamin D status, and survival in certain types of cancer. We investigated this relationship in newly diagnosed stage IV prostate cancer patients.

Methods

A consecutive cohort of 125 newly diagnosed stage IV prostate cancer patients underwent a baseline serum 25(OH)D evaluation prior to receiving any treatment at our institution between January 2008 and December 2011. We used the vitamin D categories of “deficient (<20 ng/ml)”, “insufficient (20 to 32 ng/ml)”, and “sufficient (>32 ng/ml)”. Cox regression was used to evaluate the prognostic significance of serum 25(OH)D after adjusting for relevant confounders.

Results

Mean age at diagnosis was 60 years. Of the 125 patients, 32 (25.6%) were deficient, 49 (39.2%) were insufficient and 44 (35.2%) were sufficient in vitamin D at the time of diagnosis. The median survival in deficient, insufficient and sufficient cohorts was 47.8, 44.0 and 52.6 months respectively (p = 0.60). On univariate analysis, four variables demonstrated a statistically significant association with survival: nutritional status, bone metastasis, corrected serum calcium and serum albumin (p<0.05 for all). On multivariate analysis, five variables demonstrated statistically significant associations with survival: hospital location, age, bone metastasis, serum albumin and corrected serum calcium (p<0.05 for all). Serum vitamin D status was not significant on either univariate or multivariate analysis.

Conclusion

Contrary to previously published research, we found no significant association between pre-treatment serum 25(OH)D and survival in newly diagnosed stage IV prostate cancer patients. The lack of a significant association between serum vitamin D and survival in our study could perhaps be due to the fact that the disease was far too advanced in our patients for vitamin D levels to have any impact on prognosis.     

Parathyroid Hormone as a Novel Biomarker for Chronic Obstructive Pulmonary Disease: Korean National Health and Nutrition Examination Survey

Objective

To understand and predict chronic obstructive pulmonary disease (COPD), a biomarker that reflects disease severity is needed.

Research Design and Methods

Data from 10269 adults aged over 40 years of age were retrieved from the Korea National Health and Nutrition Examination Survey (KNHANES), and 1302 patients met the criteria for COPD. The association between values of vitamin D and parathyroid hormone (PTH), and COPD severity including lung function and quality of life, were analyzed.

Results

In COPD patients, lung function was inversely related to PTH values (P = 0.02 for FVC [% predicted]; P < 0.001 for FEV₁ [% predicted]); however, the association of lung function with vitamin D levels was not statistically significant in a multivariable analysis. Value of PTH was independently associated with EQ5D-index (P = 0.04), but vitamin D level showed no significant relationship with EQ5D-index (P = 0.59) or EQ5D-VAS (P = 0.81).

Conclusions

Elevation of PTH, unlike vitamin D, is independently associated with COPD severity, and may be a better biomarker for COPD.     

Vitamin D Status among Young Children Aged 1–3 Years: A Cross-Sectional Study in Wuxi,China

Background

The increasingly recognized importance of vitamin D has been discussed and vitamin D status among young children has attracted widespread attention in recent years. However, study on vitamin D status in young children aged 1–3 y is limited in China.

Objective

To evaluate the nutritional vitamin D status of young children aged 1–3 y in Wuxi, southeastern China.

Methods

A large cohort of 5,571 young children aged 1–3 y were recruited in this study who visited the child health clinics at the Wuxi Maternity and Child Health Hospital (latitude 31.57°N) during January 2014 to January 2015. Wuxi was located in southeastern China at a latitude of 31.57°N. Finger-stick blood sampling was conducted in all the subjects and serum 25-Hydroxyvitamin D (25(OH)D) levels were measured to evaluate their vitamin D status.

Results

In this study, serum 25(OH)D levels of young children at the age of 1–3 years ranged from 20.6–132.9 nmol/L (Median: 71.5 nmol/L). 16.1% of the population had vitamin D deficiency (<50 nmol/L), while 38.8% of the subjects had a sufficient (50–74.9 nmol/L) vitamin D level. An optimal vitamin D status (≥75 nmol/L) was found in 45.1% of the young children. The prevalence of vitamin D deficiency was higher in autumn (19.5%) than in summer (12.1%). There was no significant difference in vitamin D status between genders. The binary logistic regression analysis revealed that child age was strongly associated with vitamin D deficiency (adjusted OR: 1.173; 95%CI: 1.053–1.308; P = 0.004).

Conclusions

The prevalence of vitamin D deficiency was 16.1% among young children aged 1–3 y in Wuxi. Season and child age were associated with their vitamin D status. It is implied that young children should receive adequate amounts of vitamin D supplementation and spend more time outdoors to prolong the sunlight exposure when they grow older.     

Cardio-Metabolic Disease Risks and Their Associations with Circulating 25-Hydroxyvitamin D and Omega-3 Levels in South Asian and White Canadians

Objectives

This study compared cardio-metabolic disease risk factors and their associations with serum vitamin D and omega-3 status in South Asian (SAC) and White Canadians (WC) living in Canada’s capital region.

Methods

Fasting blood samples were taken from 235 SAC and 279 WC aged 20 to 79 years in Ottawa, and 22 risk factors were measured.

Results

SAC men and women had significantly higher fasting glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), apolipoprotein B (ApoB), ratios of total (TC) to HDL cholesterol (HDLC) and ApoB to ApoA1, leptin, E-selectin, P-selectin, ICAM-1 and omega-3 (p < 0.05), but lower HDLC, ApoA1, vitamin D levels than WC (p < 0.05). SAC women had higher CRP and VEGF than WC women. Adequate (50–74.9 nmol/L) or optimal (≥ 75 nmol/L) levels of 25(OH)D were associated with lower BMI, glucose, insulin, HOMA-IR, TG, TC, low density lipoprotein cholesterol (LDLC), ApoB/ApoA1 ratio, CRP, leptin, and higher HDLC, ApoA1, omega-3 index, L-selectin levels in WC, but not in SAC. Intermediate (>4%-<8%) or high (≥ 8%) levels of omega-3 indices were related to lower E-selectin, P-selectin, ICAM-1 and higher HDLC, 25(OH)D levels in WC, but not in SAC. The BMIs of ≤ 25 kg/m² were related to lower LDLC, ApoB, VEGF, creatinine and higher 25(OH)D in WC, but not in SAC.

Conclusions

The associations of vitamin D, omega-3 status, BMI and risk factors were more profound in the WC than SAC. Compared to WC, vitamin D status and omega-3 index may not be good predictive risk factors for the prevalence of CVD and diabetes in SAC.     

Prevalence of Vitamin D Deficiency in Singapore: Its Implications to Cardiovascular Risk Factors

Objective

Vitamin D deficiency is a global health challenge and has been linked to type 2 diabetes and other chronic diseases. However, the relationship between vitamin D status, body composition, and cardiovascular risks has not been well characterized in Asian populations. The objectives of this study were to examine the factors associated with the low vitamin D levels in a sunny tropical region and to assess the role of vitamin D status in cardiovascular risk factors.

Design and Methods

This was a cross-sectional study. One hundred and fourteen healthy participants (59 males and 55 females) residing in Singapore took part in this study. Plasma 25OH-D₃ concentration was measured by using LC-MS/MS. Body fat (%) was measured by using three different techniques including bioelectrical impedance analysis (BIA), BOD POD, and dual-energy X-ray absorptiometry (DEXA). Basic anthropometric measurements, fasting blood glucose (FBG), fasting serum insulin (FSI), and lipid profiles were obtained using standard protocols.

Results

Approximately 42% of the participants were vitamin D deficient (< 20 ng/mL). Vitamin D status was inversely associated with body fat (%), homeostasis model assessment of insulin resistance (HOMA-IR), and total cholesterol/high density lipoprotein (TC/HDL) ratio, while positively associated with lean body mass (LBM) and hand grip strength (HGS).

Conclusions

The high prevalence of vitamin D deficiency in a sunny tropical region reinforces the need to recognize that sunlight alone is not the precursor for optimal vitamin D status. This raises the need to investigate public health measures that will encourage exposure to sunlight without overexposure that is harmful to skin. More importantly, vitamin D deficiency is associated with increased cardiovascular risks, i.e. HOMA-IR, TC/HDL, and LDL/HDL. Future studies should attempt to elucidate the potential mechanisms.     

Dietary Adequacy of Vitamin D and Calcium among Inuit and Inuvialuit Women of Child-Bearing Age in Arctic Canada: A Growing Concern

Background

Arctic populations are at an increased risk of vitamin D inadequacy due to geographic latitude and a nutrition transition. This study aimed to assess the adequacy of dietary vitamin D and calcium among women of child-bearing age in Arctic Canada.

Methods

This study collected data from 203 randomly selected women of child-bearing age (19-44 years) in Nunavut and the Northwest Territories of Arctic Canada. Cross-sectional surveys using a validated quantitative food frequency questionnaire were analysed to determine the dietary adequacy of vitamin D and calcium and summarize the top foods contributing to vitamin D and calcium intake among traditional food eaters (TFE) and non-traditional food eaters (NTFE).

Results

The response rate was between 69-93% depending on the community sampled. Mean BMIs for both TFE and NTFE were above the normal range. Traditional food eaters had a significantly higher median vitamin D intake compared with non-traditional eaters (TFE = 5.13±5.34 µg/day; NTFE = 3.5±3.22 µg/day, p = 0·004). The majority of women (87%) were below the Estimated Average Requirements (EAR) for vitamin D. Despite adequate median daily calcium intake in both TFE (1299±798 mg/day) and NTFE (992±704 mg/day; p = 0.0005), 27% of the study population fell below the EAR for calcium. Dairy products contributed the most to intake of vitamin D (TFE = 30.7%; NTFE = 39.1%) and calcium (TFE = 25.5%; NTFE = 34.5%).

Conclusions

Inadequate dietary vitamin D intake is evident among Inuit and Inuvialuit women of child-bearing age in Arctic Canada. Promotion of nutrient-rich sources of traditional foods, supplementation protocols and/or expanded food fortification should be considered to address this nutrition concern.     

Vitamin D,Vitamin D Binding Protein,and Longitudinal Outcomes in COPD

Background

Associations between Vitamin D₃ [25(OH)D], vitamin D binding protein (VDBP) and chronic obstructive pulmonary disease (COPD) are previously reported. We aimed to further investigate these associations on longitudinal outcomes.

Methods

426 COPD patients from western Norway, GOLD stage II-IV, aged 40–76, were followed every six-month from 2006 through 2009 with spirometry, bioelectrical impedance measurements and registration of exacerbation frequency. Serum 25(OH)D and VDBP levels were determined at study-entry by high-performance liquid chromatography coupled with mass spectrometry and enzyme immunoassays respectively. Yearly change in lung function and body composition was assessed by generalized estimating equations (GEE), yearly exacerbation rate by negative binomial regression models, and 5 years all-cause mortality by Cox proportional-hazard regression.

Results

1/3 of the patients had vitamin D deficiency (<20ng/mL) and a greater decline in both FEV1 and FVC, compared to patients with normal levels; for FEV1 this difference only reached statistical significance in the 28 patients with the lowest levels (<10ng/mL, p = 0.01). Neither 25(OH)D nor VDBP levels predicted exacerbation rate, change in fat free mass index or risk of death.

Conclusion

Severe vitamin D deficiency may affect decline in lung function parameters in COPD. Neither 25(OH)D nor VDBP levels did otherwise predict markers of disease progression.