Relationship between vitamin D and body fat distribution evaluated by DXA in postmenopausal women

Association of serum 25-hydroxy vitamin D status with cardiometabolic risk factors and total and regional obesity in southern Iran: evidence from the PoCOsteo study

Cardiometabolic risk factors increase the chance of developing cardiovascular disease (CVD) and type 2 diabetes. Most CVD risk factors are influenced by total and regional obesity. A higher risk of developing CVD may be linked to vitamin D deficiency, which is more prevalent in the older population. With the goal of evaluating the association between vitamin D and cardiometabolic risk factors and total and regional obesity in older adults, this research included 25 (OH) vitamin D3 concentrations and biochemical markers associated with cardiometabolic diseases, as well as total and regional adiposity, which was measured by DXA. A total of 1991 older participants in the PoCOsteo study were included. Overall, 38.5% of participants had vitamin D deficiency. After adjusting for confounders, the results of multiple linear and logistic regression suggested an inverse association between vitamin D and body mass index (P = 0.04), waist circumference (P = 0.001), total fat (P = 0.02), android fat (P = 0.001), visceral fat (P < 0.001), subcutaneous fat (P = 0.01), trunk fat (P = 0.006), arm fat (P = 0.03), high systolic blood pressure (P = 0.004), high total cholesterol (P < 0.001), high LDL-cholesterol (P < 0.001), high serum triglycerides (P = 0.001), and high fasting glucose (P < 0.001). Additionally, higher vitamin D concentrations decreased the risk of dyslipidemia by 2%. Our results showed a significant association between serum vitamin D and a number of cardiometabolic risk factors, including total and regional obesity.

Fat-Soluble Vitamers: Parent-Child Concordance and Population Epidemiology in the Longitudinal Study of Australian Children

Fat-soluble vitamers (FSV) are a class of diverse organic substances important in a wide range of biological processes, including immune function, vision, bone health, and coagulation. Profiling FSV in parents and children enables insights into gene-environment contributions to their circulating levels, but no studies have reported on the population epidemiology of FSV in these groups as of yet. In this study, we report distributions of FSV, their parent-child concordance and variation by key characteristics for 2490 children (aged 11-12 years) and adults (aged 28-71 years) in the Child Health CheckPoint of the Longitudinal Study of Australian Children. Ten A, D, E and K vitamers were quantified using a novel automated LC-MS/MS method. All three K vitamers (i.e., K1, MK-4, MK-7) and 1-α-25(OH)₂D₃ were below the instrument detection limit and were removed from the present analysis. We observed a strong vitamer-specific parent-child concordance for the six quantifiable A, D and E FSVs. FSV concentrations all varied by age, BMI, and sex. We provide the first cross-sectional population values for multiple FSV. Future studies could examine relative genetic vs. environmental determinants of FSV, how FSV values change longitudinally, and how they contribute to future health and disease.

Hypovitaminosis D and Metabolic Syndrome in Postmenopausal Women

Metabolic syndrome (MetSyn) is a precursor for several cardiometabolic diseases. The prevalence of MetSyn is higher in postmenopausal women compared to premenopausal women. The role of vitamin D in postmenopausal women is not clearly understood. Hypovitaminosis D is more prevalent in postmenopausal women compared to premenopausal women. For this review, Pubmed, Cochrane, SCOPUS, Embase, and Google Scholar databases were searched up to August 2022. Findings from one randomized controlled trial (RCT) and ten cross-sectional studies were included in this review. Several cross-sectional studies (8 out of 10 reviewed) unequivocally demonstrated an inverse association between serum 25-hydroxyvitamin D concentrations and MetSyn. However, RCTs are severely lacking in the effect of vitamin D intake on the biomarkers of MetSyn and the prevalence of MetSyn. Therefore, caution should be used in recommending mega doses of vitamin D supplements for postmenopausal women because of the potential adverse effects associated with this vitamer.

A Novel Biosensor and Algorithm to Predict Vitamin D Status by Measuring Skin Impedance

The deficiency and excess of vitamin D cause various diseases, necessitating continuous management; but it is not easy to accurately measure the serum vitamin D level in the body using a non-invasive method. The aim of this study is to investigate the correlation between vitamin D levels, body information obtained by an InBody scan, and blood parameters obtained during health checkups, to determine the optimum frequency of vitamin D quantification in the skin and to propose a vitamin D measurement method based on impedance. We assessed body composition, arm impedance, and blood vitamin D concentrations to determine the correlation between each element using multiple machine learning analyses and an algorithm which predicted the concentration of vitamin D in the body using the impedance value developed. Body fat percentage obtained from the InBody device and blood parameters albumin and lactate dehydrogenase correlated with vitamin D level. An impedance measurement frequency of 21.1 Hz was reflected in the blood vitamin D concentration at optimum levels, and a confidence level of about 75% for vitamin D in the body was confirmed. These data demonstrate that the concentration of vitamin D in the body can be predicted using impedance measurement values. This method can be used for predicting and monitoring vitamin D-related diseases and may be incorporated in wearable health measurement devices.

Serum 25-hydroxyvitamin D concentrations are inversely associated with body adiposity measurements but the association with bone mass is non-linear in postmenopausal women

Vitamin D deficiency has been linked to increased adiposity and decreased bone density. It is not known if vitamin D is linked to adiposity measures and bone mass in postmenopausal Qatar women. We investigated an association between serum vitamin D [25-hydroxyvitmain D (25(OH)D)] and adiposity measurements in postmenopausal women using Qatar Biobank data (n = 935). The post-menopausal status was self-reported by participants. Multivariate adjusted regression was applied to determine the association between serum 25(OH)D and body adiposity markers and bone mass. Serum 25(OH)D was significantly, inversely associated with body mass index (p < 0.0005), waist circumference (0.044), fat mass (p < 0.003), gynoid fat (p < 0.001), and android fat (p < 0.009). Serum 25(OH)D appeared to have an inverse 'U' association with several adiposity measures. Overall, body adiposity markers were the lowest in the 4^th quartile serum 25(OH)D and significantly lower compared to the 1^st quartile serum 25(OH)D. In multivariable adjusted analysis, no association was found between serum 25(OH)D concentration and bone mass when serum 25(OH)D was categorized. In a continuous variable analysis, the association between 25(OH)D and bone mass was significant, non-linear, inverse 'U'. In conclusion, serum 25-hydroxyvitamin D was inversely associated with adiposity measures and non-linearly associated to bone mass in postmenopausal Qatari women.

Effect of 1-year oral cholecalciferol on a metabolic profile and blood pressure in poor-controlled type 2 diabetes mellitus: an open-label randomized controlled pilot study

PURPOSE

Hypovitaminosis D has been associated with many cardio-metabolic disorders, although their pathogenetic link still remains unclear. Our aim was to evaluate whether 1-year vitamin D (D) supplementation could improve glycemic control, lipid profile, systolic (SBP) and diastolic (DBP) blood pressure levels and body composition.

METHODS

In an open-label randomized-controlled pilot study, thirty poor-controlled (HbA1c > 59 mmol/mol) type 2 diabetic patients (age 71.5 ± 3.2 years, M/F 21/9, BMI 29.8 ± 3.6 kg/m²) with hypovitaminosis D (25OHD 22.0 ± 11.3 nmol/l) were randomized to cholecalciferol supplementation (500 UI/kg p.o. weekly, + D) or observation (- D) for one year. Changes in parameters of glucose, lipid and blood pressure control at 3, 6, 9 and 12 months vs. baseline were assessed.

RESULTS

One-year D supplementation restored D status and had a beneficial effect on fasting glucose (FG, mean percentage changes ± SD, - 1.8% ± 23.1 vs. + 18.8% ± 30.0), glycosylated haemoglobin (HbA1c, - 13.7% ± 14.5 vs. - 4.2% ± 14.1), SBP (- 13.4% ± 8.5 vs. - 2.4% ± 12.6) and HDL-cholesterol levels (- 2.1% ± 14.0 vs. - 10.9% ± 12.9; p < 0.05 for all comparisons) in + D vs. - D patients, respectively. In the former, a reduction in HBA1c, SBP and DBP levels, BMI, fat mass index (FMI) and ratio (FMR) was observed after 1 year (p < 0.05 for all comparisons vs. baseline). We noticed a relationship between 1-year mean percentage changes of serum 25OHD and SBP levels (R = - 0.36, p < 0.05).

CONCLUSION

One-year cholecalciferol supplementation, able to restore D status, significantly improves FG, HbA1c, SBP and HDL-cholesterol levels in patients with poor-controlled type 2 diabetes mellitus and D deficiency.

Association between vitamin D deficiency and prevalence of metabolic syndrome in female population: a systematic review

BACKGROUND

The increasing prevalence of metabolic syndrome (MS) especially in female population, has become a major problem in health care systems. In this regards, it is necessary to identify the risk factors. Vitamin D deficiency is now proposed as one of the possible risk factors for metabolic syndrome, we investigated the relationship between vitamin D status and MS in female.

METHODS

We searched observational studies with keywords Vitamin D, metabolic syndrome, metabolic syndrome X, insulin-resistance syndrome, metabolic cardiovascular syndrome and Reaven Syndrome X and female in pubmed, scopus, science direct, cochrane, web of science, google scholar and SID databases, regardless of publication time. Two hundred ninety five studies were found, and finally only 12 articles were selected according to exclusion and inclusion criteria.

RESULTS

In nine studies that reported the prevalence of MS, the prevalence of MS among women with vitamin D deficiency was higher than female with normal vitamin D (34.5 vs. 30.2%). The prevalence of abdominal obesity, high blood pressure, high TG and HDL deficiency is higher in women with vitamin D deficiency. Also, the mean waist circumference, blood pressure, fast blood sugar (FBS), TG and BMI were higher. The most incident factor was high blood pressure (61.4 vs. 56.5%) and the lowest prevalence is associated with high FBS (32.2 vs. 33.5% in the other group).

CONCLUSION

The prevalence of MS is significantly associated with vitamin D deficiency, and among related factors, HDL, TG and blood pressure are statistically associated with vitamin D status.

The synergistic effects of vitamin D and estradiol deficiency on metabolic syndrome in Chinese postmenopausal women

OBJECTIVE

Recent studies show that vitamin D (VitD) deficiency is associated with metabolic syndrome (MetS). Current evidence suggests that estrogen and VitD have similar physiological functions and potentially interact with bone health. We investigated the association between estradiol (E2) and 25-hydroxyvitamin-D [25(OH)D] with MetS and its components in Chinese postmenopausal women.

METHODS

In this cross-sectional study, we examined 616 postmenopausal women (aged 49-86 y) from southern China who were not taking estrogen and VitD/calcium supplements. At the end of data collection, serum E2 and 25(OH)D were measured for each participant. MetS was defined according to the 2006 International Diabetes Federation standard.

RESULTS

There was a positive correlation between 25(OH)D and E2. Higher 25(OH)D was associated with a favorable lipid profile, blood pressure, and glucose level. E2 was negatively associated with cholesterol, triglycerides, and blood pressure. The odds ratio for MetS was 2.19 (95% CI, 1.19-4.01, P value for trend=0.009) for deficient compared with sufficient women after multivariable adjustment. This association remained unchanged after further adjusting for E2 levels. After stratified analysis by VitD status, low E2 increased MetS risk in women with VitD deficiency (odds ratio = 3.49, 95% CI, 1.45-8.05 for the lowest vs the highest tertile).

CONCLUSIONS

These results suggest a synergistic role of VitD and E2 deficiency in MetS in Chinese postmenopausal women.

Association of Hypovitaminosis D with Metabolic Syndrome in Postmenopausal Women

The prevalence of vitamin D deficiency and metabolic syndrome is spreading like a pandemic globally; postmenopausal women are particularly vulnerable population. Hypovitaminosis D is reported to predispose to various components of metabolic syndrome like dyslipidemia, hypertension, diabetes and obesity. The purpose of this review is to highlight the recently published evidence, evaluating the association of vitamin D deficiency with metabolic syndrome in postmenopausal women. Besides, it emphasizes the long-term risks involved with low vitamin D levels and importance of vitamin D supplementation. Data were obtained from PubMed, Google Scholar and individual searches.

Association between Body Fatness and Vitamin D3 Status in a Postmenopausal Population

Vitamin D is a micronutrient that plays a key role in phosphocalcic metabolism. The postmenopausal population presents a risk of deficiency in this vitamin due to hormonal alterations which, in the case of obesity, would be exacerbated. The objective was to assess the status of vitamin D in a postmenopausal population and determine the relationship of 25-hydroxivitamin D [25(OH)D] and its metabolites with anthropometric parameters. The study included 78 healthy postmenopausal women aged from 44 to 76. The nutrient intake assessment was carried out using the 24 h reminder (R24h). 25(OH)D was analyzed using ultra-high-performance liquid chromatography (UHPLC). A total of 80% and 68% of the women studied did not reach sufficient values of 25(OH)D and 25-hydroxivitamin D₃ [25(OH)D₃], respectively, which was inversely correlated with Body Mass Index (BMI) (r = −0.25, p = 0.04), hip perimeter (r = −0.26 and r = −0.24, all p < 0.05), arm circumference (r = −0.29, p = 0.01) and fat mass (r = −0.28 and r = −0.26, all p < 0.05). 25(OH)D₃ is the metabolite that contributed most to this association. In conclusion, 25(OH)D₃ levels are related to anthropometric parameters in the postmenopausal women in this study, confirming insufficient status in the majority of the population. Approach strategies are necessary to correct and avoid this risk in order to ensure future quality of life.

Association between serum 25-hydroxyvitamin D concentrations and metabolic syndrome in the middle-aged and elderly Chinese population in Dalian, northeast China: A cross-sectional study

AIMS/INTRODUCTION

To investigate the association between serum 25-hydroxyvitamin D (25-[OH]D) concentrations and metabolic syndrome (MetS) in the middle-aged and elderly Chinese population.

METHODS

The present study included 2,764 participants (aged >50 years). The joint interim statement was used for the standard definition of MetS. Serum 25-(OH)D concentrations were measured by electrochemiluminescence immunoassay. The study participants were categorized into quartiles based on serum 25-(OH)D concentrations, and the quartiles were calculated for the differences using anova and the χ2 -test for continuous and categorical data, respectively. A logistic regression analysis model was applied to estimate the odds ratios and 95% confidence intervals (95% CI) for each quartile of serum 25-(OH)D concentrations compared with the highest quartile.

RESULTS

Serum 25-(OH)D levels were markedly lower in men in the MetS group than in those without MetS. We observed a negative correlation between the higher quartiles of serum 25-(OH)D levels and the presence of MetS among men. The correlation between serum 25-(OH)D levels and the prevalence of MetS persisted even after adjusting for potential confounders, including age, cigarette smoking status, alcohol consumption, physical activity, low-density lipoprotein, creatinine and total serum cholesterol. Adjusted odds ratios of MetS in the second through fourth compared with the lowest quartile for serum 25-(OH)D levels were 0.93 (95% CI 0.54-1.59), 0.89 (95% CI 0.50-1.56) and 0.48 (95% CI 0.28-0.84), respectively.

CONCLUSIONS

Decreased serum 25-(OH)D level is significantly correlated with MetS in middle-aged men.

Serum vitamin D concentrations are inversely related to prevalence of metabolic syndrome in Qatari women

Hypovitaminosis D has reached epidemic proportions in Qatar. Vitamin D is linked to several cardiometabolic diseases such as metabolic syndrome (MetSyn), diabetes, and atherosclerosis. It is not known if vitamin D status is linked to cardiometabolic risk factors in Qatari women. Therefore, a relationship between serum 25-hydroxyvitmain D [25(OH)D] concentrations and MetSyn was investigated in Qatari women using the Qatar Biobank database. Study sample consisted of 700 women, aged 20-80 years old. A multivariate-adjusted logistic regression was used to determine relation between serum 25(OH)D and MetSyn prevalence. Multivariate linear regression was performed to determine the association between serum 25(OH)D and markers of MetSyn. Prevalences of MetSyn in the first (≈32%), second (≈27%), and third (≈28%) serum 25(OH)D quartiles were significantly higher compared to fourth serum 25(OH)D quartile (≈17.5%) (p < .035). The likelihood of having MetSyn was significantly higher in the first serum 25(OH)D quartile (OR, 1.92; 95% CI, 1.06, 3.49) compared to the fourth serum 25(OH)D quartile (p < .001) in multivariate-adjusted analysis. No relationship was observed between serum 25(OH)D and waist circumference, blood pressure, glycated hemoglobin (HbA1C), blood glucose, HDL-cholesterol, and serum triglycerides. This study showed an inverse relationship between prevalence of MetSyn and serum 25(OH)D in Qatari women. Given the widespread prevalence of vitamin D deficiency in Qatar, consideration should be given to vitamin D fortification of some selected staple foods and through targeted supplementation of vitamin D in those who are at risk for cardiometabolic diseases.

Prevalence of hypovitaminosis D in postmenopausal women: a systematic review

BACKGROUND

Hypovitaminosis D is considered a global public health issue. Knowledge of its true dimensions will allow us to design interventions and plan preventive measures that can have a significant impact on human health.

OBJECTIVES

The aim of this study was to evaluate the prevalence of hypovitaminosis D, defined as a serum 25-hydroxyvitamin D concentration < 30 ng/ml, in postmenopausal women around the world, as well as to identify the potential associated factors.

METHODS

A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses recommendations. Specific search terms were consulted in Medline, Excerpta Medica, and Latin-American and Caribbean Health Sciences Literature databases, with no restriction for the year or language of publication.

RESULTS

Of 451 studies initially identified, 32 were selected for analysis. Collectively, those 32 studies evaluated 21,236 postmenopausal women, of whom 16,440 (77.4%) had serum 25-hydroxyvitamin D concentrations < 30 ng/ml. The reported prevalence of hypovitaminosis D ranged from 29% (in the United States) to 99.4% (in China). In six of the studies, the prevalence was above 90%.

CONCLUSIONS

If the criterion is the 30 ng/ml cut-off point, the majority of postmenopausal women in the world could be classified as having hypovitaminosis D. Among the studies evaluated, the lowest prevalence reported was nearly 30%. Neither latitude, region of the world, nor laboratory methodology were found to be associated with the prevalence of hypovitaminosis D.

Bone metabolism markers are associated with neck circumference in adult Arab women

The study aimed to determine whether neck circumference is associated with bone metabolism markers among adult Arab women and found modest but significant associations with bone resorption markers, suggesting that neck circumference, a surrogate measure of upper subcutaneous fat, influences bone turnover expression among adult females.

INTRODUCTION

Body fat distribution is associated with decreased bone resorption and neck circumference (NC), a surrogate measure for upper body fat, has never been tested as a marker that can reflect bone turnover. This is the first study aimed to analyze the associations between NC and several bone biomarkers among adult Saudi women.

METHODS

This cross-sectional study included a total of 265 middle-aged Saudi women [86 non-obese (mean age 52.7 ± 8.1; mean BMI 26.9 ± 2.3) and 179 obese (mean age 50.6 ± 7.5; mean BMI 35.7 ± 4.5)] recruited from primary care centers in Riyadh, Saudi Arabia. Anthropometrics included BMI, NC, waist and hip circumferences, total body fat percentage (%), and blood pressure. Biochemical parameters included glucose and lipid profile which were measured routinely. Serum levels of 25(OH) D, parathyroid hormone, RANKl, sclerostin, C-terminal telopeptide of collagen I (CTX-I), Dkk1, IL1β, osteoprotegerin, osteopontin, and osteocalcin were measured using commercially available assays.

RESULTS

In all groups, NC was inversely associated with PTH (R = - 0.22; p < 0.05) and positively associated with osteoprotegerin (R = 0.20; p < 0.05) even after adjustments for age and BMI. Using all anthropometric indices as independent variables showed that only NC explained the variance perceived in CTX-I (p = 0.049). In the non-obese, waist-hip ratio (WHR) was significantly associated with sclerostin (R = 0.40; p < 0.05) and body fat was significantly associated with osteopontin (R = 0.42; p < 0.05).

CONCLUSION

NC is modestly but significantly associated with bone biomarkers, particularly the bone resorption markers, among adult Arab women. The present findings highlight the importance of NC as measure of upper body subcutaneous fat in influencing bone biomarker expression in adult females.

Obesity attenuates serum 25-hydroxyvitamin D response to cholecalciferol therapy in critically ill patients

OBJECTIVES

The presence of obesity may confound cholecalciferol dosing in vitamin D-deficient patients owing to potentially decreased bioavailability. The aim of this retrospective study was to evaluate cholecalciferol therapy in vitamin D-deficient, critically ill trauma patients with and without obesity.

METHODS

Adult patients with severe traumatic injuries who had a serum 25-hydroxyvitamin D (25-OH vit D) <50nmol/L were prescribed 10 000 IU of liquid cholecalciferol daily. Efficacy was defined as achievement of a 25-OH vit D of 75 to 200nmol/L. Safety was evaluated by the presence of hypercalcemia (serum ionized calcium >1.32 mmol/L). Fifty-three patients (18 obese, 35 non-obese) were identified for study.

RESULTS

Despite similar baseline concentrations (36 ± 7 versus 37 ± 7 nmol/L; P = NS), 25-OH vit D response was attenuated for those with obesity after 1 and 2 wk of cholecalciferol therapy (51 ± 18 versus 66 ± 27nmol/L, P < 0.01; 68 ± 19 versus 92 ± 25nmol/L, P < 0.01, respectively). Patients with obesity also tended to experience less hypercalcemia (22% versus 49% of patients, respectively) post-cholecalciferol therapy.

CONCLUSION

Obesity alters the response to cholecalciferol therapy in critically ill patients with severe traumatic injuries.

Body Mass Index, Vitamin D, and Type 2 Diabetes: A Systematic Review and Meta-Analysis

The deficiency of vitamin D is prevalent all over the world. Studies have shown that vitamin D may play an important role in the development of obesity. The current study was conducted to quantitatively evaluate the association between serum 25-(OH) vitamin D levels and the risk of obesity in both diabetic and non-diabetic subjects. A systematic review and meta-analysis of observational studies was carried out for that purpose. We searched the Medline, PubMed, and Embase databases throughout all of March 2018. A total of fifty five observational studies for both diabetic and non-diabetic subjects were finally included in the meta-analysis. The data were analyzed by comprehensive meta-analysis software version 3 and the random effects model was used to analyze the data. The meta-analysis showed an overall inverse relationship between serum vitamin D status and body mass index (BMI) in studies of both diabetic (r = −0.173, 95% = −0.241 to −0.103, p = 0.000) and non-diabetic (r = −0.152, 95% = −0.187 to −0.116, p = 0.000) subjects. The evidence of publication bias was not found in this meta-analysis. In conclusion, the deficiency of vitamin D is associated with an increased level of BMI in the studies of both diabetic and non-diabetic subjects. Reliable evidence from well-designed future randomized controlled trials is required to confirm the findings from observational studies and to find out the potential regulatory effects of vitamin D supplementation to lower BMI.

Vitamin D status and body composition: a cross-sectional study among employees at a private university in Lebanon

Background

The prevalence of low vitamin D status is increasing globally, and Lebanon is not spared. The objectives of this study are to determine the prevalence and correlates of low vitamin D status, and to assess the association between percent body fat and vitamin D status, independently of obesity.

Methods

A cross-sectional study was performed on NDU employees. Data on dietary intake, physical activity, lifestyle, health status, and demographic variables were collected during a face-to-face interview. Anthropometric measures (weight, height and waist circumference) were measured and body composition was assessed using the bioelectrical impedance analysis (BIA) machine InBody 720 (Biospace, Seoul, Korea). The Nutritionist Pro diet analysis software version 31.0 was used to estimate dietary intake of vitamin D. Serum 25 hydroxyvitamin D (25(OH)D) was measured using enzyme linked immunosorbent assay kit (ELISA) (Calbiotech, Spring Valley, California, USA). Vitamin D status was assessed according to the National Osteoporosis Foundation (sufficiency: ≥ 75 nmol/L / ≥30 ng/mL) and the Institute of Medicine cut-offs (adequacy: ≥50 nmol/L / ≥20 ng/mL). Statistical analyses were performed by SPSS version 22.

Results

A total of 344 employees (50% Male) aged between 20 and 74 years participated in the study. More than half of the participants were overweight and obese. Mean serum vitamin D concentrations were 28.2 ± 13.9 ng/mL. Among participants, 37.5% of our study population had 25(OH)D ≥ 30 ng/mL, and 68.3% had 25(OH)D ≥ 20 ng/mL. Individuals with low vitamin D status had significantly higher percent body fat (PBF) (p < 0.005), and higher waist circumference (WC) (p = 0.012) than in the sufficient group, however BMI did not differ by vitamin D status. Logistic regression analysis indicated that a 1% increase in body fat increases the odds of having 25(OH)D ≤ 30 ng/mL by 8% while controlling for BMI and other confounders (p = 0.019).

Conclusion

This study reinforces the need for regular screening for low vitamin D status in Lebanese adults, particularly individuals at risk, including those with high risk WC, high PBF, who work indoors and have low vitamin D intake, and recommending vitamin D supplementation if needed.

Fat Mass Is Associated with Serum 25-Hydroxyvitamin D Concentration Regardless of Body Size in Men

There are no large community-based studies examining the association of body size vs. body fat with vitamin D status. Association of serum 25-hydroxyvitamin D (25OHD) with body weight and subcategories of body weight defined by fat mass were evaluated in a large, free living population. Out of a total of 29,235 subjects from the 2008–2010 Korean National Health and Nutrition Examination Survey, the relevant data included 6458 subjects over 50 years of age who were analyzed cross-sectionally. Serum 25OHD concentrations were compared in men (n = 3164) and in women (n = 3294) by tertiles of body weight and body fat mass, as measured by Dual-energy X-ray Absorptiometry (DXA) within sex-specific tertiles of body weight. Serum 25OHD was weakly inversely correlated with body weight in the men and the women after adjustment for age (r = −0.075 and −0.073, respectively, p < 0.001 for both). Within each tertile of body weight, serum 25OHD decreased progressively as fat mass increased in men. This pattern was similar in the women but not consistently significant. Whereas body weight predicted a small decrease in serum 25OHD in the men and the women, greater adiposity, for any given weight, predicted larger decreases in the men, but not consistently in women.

Serum Lipid, Vitamin D Levels, and Obesity in Perimenopausal and Postmenopausal Women in Non-Manual Employment

BACKGROUND Increasing age, increased body mass index (BMI), and abnormal lipid profiles contribute to an increased risk of vitamin D deficiency. Women who have a perimenopausal and postmenopausal reduction in estrogen levels are a high-risk group for vitamin D deficiency. The aims of this study were to compare the serum vitamin D levels, lipid profile, and BMI between perimenopausal and postmenopausal women in non-manual employment, and to determine whether there were any interdependent factors. MATERIAL AND METHODS Three hundred women in non-manual employment, aged between 44-66 years, were divided into three groups: early perimenopausal; late perimenopausal; and postmenopausal. Laboratory tests included measurement of serum lipid profiles and vitamin D levels, the BMI, waist-hip ratio (WHR) and body fat were measured. Statistical analysis included F-test analysis of variance and the least significance difference (LSD) test was used for multiple comparisons. RESULTS For the 300 women who were in non-manual employment, and in the early and late perimenopausal and postmenopausal periods, serum vitamin D levels were reduced (mean 16.8±8.7 ng/mL); 29% of women had abdominal obesity; 41% had excessive body fat accumulation; and 56% had an increased body mass index (BMI) (>25 kg/m²) with raised total cholesterol, low-density lipoprotein (LDL) cholesterol, LDL/high-density lipoprotein (HDL), and total cholesterol/HDL ratios (p<0.05). CONCLUSIONS The findings of this study showed that in perimenopausal and postmenopausal women in non-manual employment, serum vitamin D levels were associated with serum lipid profile and degrees of obesity.

Vitamin D deficiency is associated with metabolic syndrome in postmenopausal women

OBJECTIVE

To evaluate the association between vitamin D (VD) deficiency and risk factors for metabolic syndrome (MetS) in postmenopausal women.

STUDY DESIGN

Observational, cross-sectional cohort study.

MAIN OUTCOME MEASURES

In this study, 463 women, aged 45-75 years, with amenorrhea >12months, without VD supplementation or established cardiovascular disease were included. Clinical and anthropometric data were collected. Biochemical parameters, including total cholesterol (TC), HDL, LDL, triglycerides, glucose, insulin and 25-hydroxyvitamin-D [25(OH)D] were measured. Women meeting three or more of the following criteria were diagnosed with MetS: waist circumference >88cm, triglycerides ≥150mg/dL, HDL <50mg/dL, blood pressure ≥130/85mmHg and glucose ≥100mg/dL. Serum 25(OH)D levels were classified as sufficient (≥30ng/mL), insufficient (20-29ng/mL) or deficient (<20ng/mL). ANOVA, chi-square test and logistic regression (odds ratio, OR) were used for statistical analysis.

RESULTS

Serum 25(OH)D levels were sufficient in 148 women (32.0%), insufficient in 151 (32.6%) and deficient in 164 (35.4%). Women with low 25(OH)D levels had higher TC, triglycerides, insulin and HOMA-IR levels (p<0.05). MetS was detected in 57.8% (182/315) of women with hypovitaminosis D (insufficient and deficient) and in 39.8% (59/148) of those with sufficient VD​​ (p=0.003). In a multivariate logistic regression analysis, a low 25(OH)D level (<30ng/mL) was significantly associated with MetS (OR1.90, 95%CI=1.26-2.85), high triglyceride levels (OR1.55, 95%CI=1.13-2.35), and low HDL levels (OR1.60, 95%CI=1.19-2.40) (p<0.05) compared with women with sufficient 25(OH)D levels, after adjusting for age, time since menopause, body mass index, smoking and physical exercise. The mean concentration of 25(OH)D decreased with increasing numbers of MetS components (p=0.016).

CONCLUSIONS

VD deficiency in postmenopausal women was associated with a higher prevalence of MetS. Women with VD deficiency had a higher risk of MetS, hypertriglyceridemia and low HDL than those with adequate levels.

25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 exert distinct effects on human skeletal muscle function and gene expression

Age-associated decline in muscle function represents a significant public health burden. Vitamin D-deficiency is also prevalent in aging subjects, and has been linked to loss of muscle mass and strength (sarcopenia), but the precise role of specific vitamin D metabolites in determining muscle phenotype and function is still unclear. To address this we quantified serum concentrations of multiple vitamin D metabolites, and assessed the impact of these metabolites on body composition/muscle function parameters, and muscle biopsy gene expression in a retrospective study of a cohort of healthy volunteers. Active serum 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), but not inactive 25-hydroxyvitamin D3 (25OHD3), correlated positively with measures of lower limb strength including power (rho = 0.42, p = 0.02), velocity (Vmax, rho = 0.40, p = 0.02) and jump height (rho = 0.36, p = 0.04). Lean mass correlated positively with 1α,25(OH)2D3 (rho = 0.47, p = 0.02), in women. Serum 25OHD3 and inactive 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) had an inverse relationship with body fat (rho = -0.30, p = 0.02 and rho = -0.33, p = 0.01, respectively). Serum 25OHD3 and 24,25(OH)2D3 were also correlated with urinary steroid metabolites, suggesting a link with glucocorticoid metabolism. PCR array analysis of 92 muscle genes identified vitamin D receptor (VDR) mRNA in all muscle biopsies, with this expression being negatively correlated with serum 25OHD3, and Vmax, and positively correlated with fat mass. Of the other 91 muscle genes analysed by PCR array, 24 were positively correlated with 25OHD3, but only 4 were correlated with active 1α,25(OH)2D3. These data show that although 25OHD3 has potent actions on muscle gene expression, the circulating concentrations of this metabolite are more closely linked to body fat mass, suggesting that 25OHD3 can influence muscle function via indirect effects on adipose tissue. By contrast, serum 1α,25(OH)2D3 has limited effects on muscle gene expression, but is associated with increased muscle strength and lean mass in women. These pleiotropic effects of the vitamin D 'metabolome' on muscle function indicate that future supplementation studies should not be restricted to conventional analysis of the major circulating form of vitamin D, 25OHD3.

Vitamin D deficiency in critically ill patients with traumatic injuries

Background

Vitamin D depletion has been associated with increased rate of infections, lengthened hospital stay, and worsened mortality for critically ill patients. The purpose of this study was to evaluate the prevalence and variables associated with vitamin D deficiency in critically ill patients with severe traumatic injuries.

Methods

Critically ill adult patients admitted to the trauma intensive care unit (ICU) between June 2013 and June 2014, referred to the nutrition support service for enteral or parenteral nutrition, and had a serum 25-hydroxyvitamin D (25-OH vitamin D) concentration determination were retrospectively evaluated. Patients were stratified as vitamin D sufficient, insufficient, deficient, or severely deficient based on a 25-OH vitamin D concentration of 30–80, 20–29.9, 13.1–19.9, and ≤13 ng/mL, respectively.

Results

One hundred and twenty-one patients out of 158 (76 %) patients were vitamin D deficient or severely deficient. Thirty-one patients (20 %) were insufficient and 6 (4 %) had a normal 25-OH vitamin D concentration. 25-OH vitamin D was determined 7.5 ± 5.1 days after ICU admission. African-Americans had a greater proportion of patients with deficiency or severe deficiency compared to other races (91 versus 64 %, P = 0.02). Penetrating gunshot or knife stab injury, African-American race, and obesity (elevated body mass index) were significantly associated with vitamin D deficiency or severe deficiency: OR 9.23 (1.13, 75.40), 4.0 (1.4, 11.58), and 1.12 (1.03, 1.23), P < 0.05, respectively.

Conclusions

The majority of critically ill patients with traumatic injuries exhibit vitamin D deficiency or severe deficiency. Penetrating injuries, African-American race, and obesity are significant risk factors for deficiency. Severity of injury, extent of inflammation (elevated C-reactive protein concentration), or hospital admission during the winter season did not significantly influence the prevalence of vitamin D deficiency.

25-hydroxyvitamin D is associated with metabolic syndrome among premenopausal women with systemic lupus erythematosus in China

Objectives

This study aimed to investigate the status of 25-hydroxyvitamin D (25(OH)D) and its association with metabolic syndrome (MS) and different MS components among premenopausal women with systemic lupus erythematosus (SLE) in China.

Patients and methods

Altogether 113 premenopausal women with SLE and the age-matched healthy cohorts were recruited in this cross-sectional study. Clinical manifestations and laboratory data including serum 25(OH)D concentration were collected. A multivariable analysis was performed to analyze the association of 25(OH)D with MS and its components.

Results

The prevalence of 25(OH)D deficiency (25(OH)D < 20 ng/ml) and MS were common (24.8% and 30.1%, respectively) in premenopausal patients with SLE in China. Analysis of the association between 25(OH)D, MS and its components demonstrated that the lower level of 25(OH)D was associated with increased MS prevalence (OR = 0.920, p = 0.012), a decreased level of high-density lipoprotein (OR = 1.059, p = 0.033) and a higher level of fasting glucose (OR = 0.810, p = 0.004). These associations were still detectible after adjustment for age, body mass index and SLE-related variables.

Conclusion

The level of 25(OH)D is associated with MS and its components in premenopausal women with SLE.