Low Serum Concentrations Of 25-hydroxyvitamin Research Articles

Association between Vitamin D Intake and Its Beneficial Effect on Cardiometabolic Disorders in Children and Adolescents with Obesity

Introduction-Purpose: It is a fact that there has been a dramatic increase in the global prevalence of overweight children and adolescents with obesity in the last decade. From the existing literature, it has been shown that it is somehow related to the low serum concentration of 25-hydroxyvitamin D (s25(OH)D). Several studies suggest the consumption of vitamin D supplements in children-adolescent patients with obesity, despite its controversial effectiveness. The aim is to detect a correlation and evaluate the intake of vitamin D supplements and its effectiveness in the treatment of metabolic disorders of overweight and obese children-adolescents. Material and Method: A review of current literature on vitamin D and cardiometabolic syndrome (MetS) in children and adolescents was carried out, using several databases such as PubMed, Cross Ref, Cochrane Library and Google Scholar. Results: A combination of available sources shows that insufficient vitamin D levels have the potential to affect various aspects of health, including cardiovascular well-being. In children-adolescents with obesity, there is difficulty in increasing vitamin D levels due to its possible thinning in adipose tissue, either due to limited exposure to sunlight or due to low consumption of foods rich in vitamin D. Recommended doses daily vitamin D consumption is usually >4,000IU. A positive impact has been found with vitamin D restoration therapy on insulin secretion and function, improvement of lipid profile and reduction of body mass index (BMI). However, the effect of vitamin D appears to have limited clinical significance and controversial cardiovascular and metabolic effects. Conclusions: In conclusion, it has been found that the consumption of vitamin D supplements slightly increases s25(OH)D levels in overweight-obese children-adolescents and that there is a link between its increase and its effects on certain complications that follow the disease. Nevertheless, more extensive research, continued vigilance of relevant bodies and parents and efforts to promote effective interventions to improve the health of parents are recommended. overweight children-adolescents.

Sharpening the global focus on ethnicity and race in the time of COVID-19

Sharpening the global focus on ethnicity and race in the time of COVID-19

Quality assessment of systematic reviews of vitamin D, cognition and dementia.

There is conflicting evidence regarding the association of vitamin D with cognition performance and dementia.AimsWe aimed to summarise the evidence on the association of vitamin D with cognitive performance, dementia and Alzheimer disease through a qualitative assessment of available systematic reviews and meta-analyses. We conducted an overview of the systematic reviews of all study types with or without meta-analyses on vitamin D and either Alzheimer disease, dementia or cognitive performance up to June 2017. Eleven systematic reviews were identified, nine of which were meta-analyses with substantial heterogeneity, differing statistical methods, variable methodological quality and quality of data abstraction. A Measurement Tool to Assess Systematic Reviews checklist scores ranged from 4 to 10 out of 11, with seven reviews of 'moderate' and four of 'high' methodological quality. Out of six meta-analyses on the association between low serum concentration of 25-hydroxyvitamin D and risk of dementia, five showed a positive association. Results of meta-analyses on the association between low serum concentration of 25-hydroxyvitamin D and memory function tests showed conflicting results. This systematic evaluation of available systematic reviews provided a clearer understanding of the potential link between low serum vitamin D concentrations and dementia. This evaluation also showed that the quality of the available evidence is not optimal because of both the low methodological quality of the reviews and low quality of the original studies. Interpretation of these systematic reviews should therefore be made with care.Declaration of interestNone.

The Risk of Acute Rejection Following Kidney Transplant by 25-Hydroxyvitamin D and 1,25-Dihydroxyvitamin D Status: A Prospective Cohort Study.

Background:Prediction of acute kidney transplant rejection remains imperfect despite several known risk factors. There is an increasing appreciation of the potential importance of the vitamin D pathway in immunological disease and transplantation.Objective:The purpose of this study was to determine the association of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D with acute rejection.Design:This was a prospective cohort study.Setting:Three academic adult kidney transplant programs in Ontario, Canada, were chosen.Patients:All consecutive adult patients at the 3 institutions who received a solitary kidney transplant, were able to provide written informed consent, and planned to be followed at the same center post-operatively were included.Measurements:Serum concentration of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were measured at baseline, 3, and 6 months post-transplantation. Acute rejection was classified using Banff criteria.Methods:The co-primary outcome was the association between 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D and time to first occurrence of biopsy-proven acute rejection (BPAR) within the first year after kidney transplantation. Cox proportional hazards models were fitted taking into account the time-varying nature of serum concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D.Results:From 556 screened patients, data on 327 kidney transplant recipients are included. First BPAR occurred in 54 (16.5%) patients. In adjusted Cox proportional hazards models, the serum concentration of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D was not associated with acute renal transplant rejection (hazard ratio 1.00; 95% [confidence interval] CI, 0.87-1.14, per 10 nmol/L increase, and hazard ratio 0.97; 95% CI, 0.84-1.12, per 10 pmol/L increase, respectively).Limitations:Given the observational design, we cannot rule out the possibility of residual confounding that limited our ability to detect a clinically significant effect of vitamin D metabolites on acute rejection.Conclusions:A low serum concentration of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D is not associated with an increased risk of acute kidney transplant rejection following kidney transplantation.

Low serum concentrations of 25-hydroxyvitamin D in children and adolescents with systemic lupus erythematosus.

We evaluated the concentrations of 25-hydroxyvitamin D [25(OH)D] in children and adolescents with juvenile systemic lupus erythematosus (JSLE) and associated them with disease duration and activity, use of medication (chloroquine and glucocorticoids), vitamin D intake, calcium and alkaline phosphatase levels, and bone mineral density. Thirty patients with JSLE were evaluated and compared to 30 healthy individuals, who were age and gender matched. Assessment was performed of clinical status, disease activity, anthropometry, laboratory markers, and bone mineral density. The 30 patients included 25 (83.3%) females and 16 (53.3%) Caucasians, with a mean age of 13.7 years. The mean age at diagnosis was 10.5 years and mean disease duration was 3.4 years. Mean levels of calcium, albumin, and alkaline phosphatase were significantly lower in patients with JSLE compared with controls (P<0.001, P=0.006, and P<0.001, respectively). Twenty-nine patients (97%) and 23 controls (77%) had 25(OH)D concentrations lower than 32 ng/mL, with significant differences between them (P<0.001). Fifteen patients (50%) had vitamin D levels <20 ng/mL and 14 had vitamin D levels between 20 and 32 ng/mL. However, these values were not associated with greater disease activity, higher levels of parathormone, medication intake, or bone mineral density. Vitamin D concentrations were similar with regard to ethnic group, body mass index, height for age, and pubertal stage. Significantly more frequently than in controls, we observed insufficient serum concentrations of 25(OH)D in patients with JSLE; however, we did not observe any association with disease activity, higher levels of parathormone, lower levels of alkaline phosphatase, use of medications, or bone mineral density alterations.

A predictive equation to guide vitamin D replacement dose in patients.

Vitamin D is essential for bone health and probably the health of most nonskeletal tissues. Vitamin D deficiency is widespread, and recommended doses are usually inadequate to maintain healthy levels. We conducted a retrospective observational study to determine whether the recommended doses of vitamin D are adequate to correct deficiency and maintain normal levels in a population seeking health care. We also sought to develop a predictive equation for replacement doses of vitamin D. We reviewed the response to vitamin D supplementation in 1327 patients and 3885 episodes of vitamin D replacement and attempted to discern factors affecting the response to vitamin D replacement by conducting multiple regression analyses. For the whole population, average daily dose resulting in any increase in serum 25-hydroxyvitamin D level was 4707 IU/day; corresponding values for ambulatory and nursing home patients were 4229 and 6103 IU/day, respectively. Significant factors affecting the change in serum concentrations of 25-hydroxyvitamin D, in addition to the dose administered, are (1) starting serum concentration of 25-hydroxyvitamin D, (2) body mass index (BMI), (3) age, and (f) serum albumin concentration. The following equation predicts the dose of vitamin D needed (in international units per day) to affect a given change in serum concentrations of 25-hydroxyvitamin D: Dose = [(8.52 - Desired change in serum 25-hydroxyvitamin D level) + (0.074 × Age) - (0.20 × BMI) + (1.74 × Albumin concentration) - (0.62 × Starting serum 25-hydroxyvitamin D concentration)]/(-0.002). Analysis of the dose responses among 3 racial groups-white, black, and others-did not reveal clinically meaningful differences between the races. The main limitation of the study is its retrospective observational nature; however, that is also its strength in that we assessed the circumstances seen in usual health care setting. The recommended daily allowance for vitamin D is grossly inadequate for correcting low serum concentrations of 25-hydroxyvitamin D in many adult patients. About 5000 IU vitamin D3/day is usually needed to correct deficiency, and the maintenance dose should be ≥2000 IU/day. The required dose may be calculated from the predictive equations specific for ambulatory and nursing home patients.

Vitamin D Status Is Associated With Grip Strength in Centenarians

Low serum concentrations of 25-hydroxyvitamin D (25(OH)D) have been associated with poor physical function in older adults, but few, if any, studies have examined this relationship in the very old. Therefore, the purpose of this study is to examine this relationship in the very old. Serum 25(OH)D concentrations were obtained from 194 centenarians and near centenarians (98 years and older). The associations between 25(OH)D concentrations and measures of physical function were evaluated with unadjusted and adjusted regression models. We found that 35% of centenarians had 25(OH)D concentrations less than 50 nmol/L. Adjusted mean grip strength was lower for centenarians with 25(OH)D concentrations less than 75 nmol/L than for centenarians with higher concentrations (P<0.05). However, there were no differences in the Georgia Centenarian Study (GCS) Composite Scale, a global measure of physical function, between those with higher and lower 25(OH)D concentrations. We conclude that low 25(OH)D concentrations are associated with poor grip strength, but not GCS Composite Scale, in the very old. Considering the high burden of poor physical function in older adults, understanding the relationship between vitamin D and different measures of physical function, including strength, becomes increasingly important.

Serum 25-Hydroxyvitamin D and Incidence of Fatal and Nonfatal Cardiovascular Events: A Prospective Study With Repeated Measurements

Several studies suggested that low serum concentrations of 25-hydroxyvitamin D (25(OH)D) are associated with an increased risk of cardiovascular disease (CVD). However, the evidence is still inconclusive, mostly based on CVD mortality and studies with single 25(OH)D measurements. We aimed to assess the association of 25(OH)D with fatal and nonfatal CVD in the same study population, using repeated 25(OH)D measurements and competing risks analysis. This was a population-based cohort study (ESTHER study, baseline 2000-2002). Follow-up data, including survival status, were collected after 2, 5, and 8 years. The response rate for survival was 99.9%. Participants were recruited during a health screening examination by their general practitioners. 25(OH)D was measured in blood samples collected at baseline and the 5-year follow-up visit. A total of 9949 men and women, aged 50 to 74 years at baseline, with sufficient knowledge of the German language and resident in the German state of Saarland were included in the study. Outcomes included CVD, coronary heart disease (CHD), and stroke, in total and differentiated into fatal and nonfatal events. Overall, 854 study participants had a nonfatal and 176 a fatal CVD event during 8 years of follow-up. Comparing subjects with 25(OH)D levels below 30 nmol/L and above 50 nmol/L resulted in a hazard ratio of 1.27 (95% confidence interval = 1.05-1.54) for total CVD and 1.62 (95% confidence interval = 1.07-2.48) for fatal CVD in a model adjusted for important potential confounders. No significant association for nonfatal CVD was observed. In dose-response analysis, we observed an increased cardiovascular risk at 25(OH)D levels below 75 nmol/L. Results for CHD and stroke were comparable to the results obtained for the composite outcome CVD. Our results support evidence that low 25(OH)D levels are associated with moderately increased risk of CVD and indicate that the observed association is much stronger for fatal than for nonfatal events.

Vitamin D supplementation in a healthy, middle-aged population: actual practices based on data from a French comprehensive regional health-care database

The debate surrounding recommendations for vitamin D supplementation in middle-aged patients (that is, 20-60 years of age) with low serum concentrations of 25-hydroxyvitamin D (25(OH)D) is growing. Our aim was to describe practices regarding vitamin D supplementation in this age group, which are basically unknown. We performed an analysis using exhaustive reimbursement data from the individuals in Rhône-Alpes area, a French region regrouping more than 6 million of inhabitants. The data were collected from the French Insurance Health-care System. Patients who were 20-60 years of age, had no severe comorbidities, had a 25(OH)D assay between 1 December 2008 and 31 January 2009 were identified. Those who received a subsequent prescription for vitamin D were included in this analysis. We described patterns of vitamin D supplementation by frequency and daily dose. The sample in this study included 1311 patients. The mean age was 47.7 years (s.d.: 9.5) and the median age was 50.2 years. Most of the participants (that is, 85.9%) were women. A total of 372 distinct prescription patterns for vitamin D supplementation were observed. The two most frequent (that is, 32.6% in total) involved a unique dispensation of a high dose of either 200,000 (17.5%) or 100,000 IU (15.1%). Most prescribed supplements were based on vitamin D3 (65%), and the most prescribed forms were high dose ampoules (81.6%). Only 48.9% of the participants were given a maintenance prescription after the initial loading phase. Our results reveal a significant variability in the prescriptions for vitamin D supplementation from physicians in the French population. Moreover, less than half of the patients receive maintenance therapy after the initial loading phase of supplementation.

Maternal vitamin D deficiency causes smaller muscle fibers and altered transcript levels of genes involved in protein degradation, myogenesis, and cytoskeleton organization in the newborn rat

Epidemiologic data reveal associations between low serum concentrations of 25-hydroxyvitamin D (25(OH)D) and higher risk of falls and muscle weakness. Fetal stage is critical for the development of skeletal muscle, but little information is available on the impact of maternal vitamin D deficiency on muscles of offspring. To investigate the morphology and transcriptome of gastrocnemius muscle in newborns in response to maternal vitamin D deficiency, 14 female rats were fed either a vitamin D₃ deficient (0 IU/kg) or a vitamin D₃ adequate diet (1000 IU/kg) 8 weeks prior to conception, during pregnancy, and lactation. Analysis of cholecalciferol, 25(OH)D₃ and 1,25-dihydroxyvitamin D₃ show that dams fed the vitamin D deficient diet and their newborns suffered from a relevant vitamin D deficiency. Muscle cells of vitamin D deficient newborns were smaller than those of vitamin D adequate newborns (p < 0.05). Muscle transcriptome of the newborns revealed 426 probe sets as differentially expressed (259 upregulated, 167 downregulated) in response to vitamin D deficiency (fold change ≥1.5, p < 0.05). The effected genes are involved in protein catabolism, cell differentiation and proliferation, muscle cell development, and cytoskeleton organization. Maternal vitamin D deficiency has a major impact on morphology and gene expression profile of skeletal muscle in newborns.

Daily consumption of vitamin D– or vitamin D + calcium–fortified yogurt drink improved glycemic control in patients with type 2 diabetes: a randomized clinical trial

Low serum concentrations of 25-hydroxyvitamin D [25(OH)D] have been associated with impaired glucose tolerance and diabetes. This study aimed to compare the effects of daily intake of vitamin D- or vitamin D(3) + calcium-fortified yogurt drink on glycemic status in subjects with type 2 diabetes (T2D). Ninety diabetic subjects were randomly allocated to 3 groups to consume plain yogurt drink (PY; containing no vitamin D and 150 mg Ca/250 mL), vitamin D-fortified yogurt drink (DY; containing 500 IU vitamin D(3) and 150 mg Ca/250 mL), or vitamin D + calcium-fortified yogurt drink (DCY; containing 500 IU vitamin D(3) and 250 mg Ca/250 mL) twice per day for 12 wk. Fasting serum glucose (FSG), glycated hemoglobin (Hb A(1c)), homeostasis model assessment of insulin resistance (HOMA-IR), serum lipid profile, and percentage fat mass (FM) were assessed before (baseline) and after the intervention. In both the DY and DCY groups, mean serum 25(OH)D(3) improved (+32.8 ± 28.4 and +28.8 ± 16.1 nmol/L, respectively; P < 0.001 for both), but FSG [-12.9 ± 33.7 mg/dL (P = 0.015) and -9.6 ± 46.9 mg/dL (P = 0.035)], Hb A(1c) [-0.4 ± 1.2% (P < 0.001) and -0.4 ± 1.9% (P < 0.001)], HOMA-IR [-0.6 ± 1.4 (P = 0.001) and -0.6 ± 3.2 (P < 0.001)], waist circumference (-3.6 ± 2.7 and -2.9 ± 3.3; P < 0.001 for both), and body mass index [in kg/m(2); -0.9 ± 0.6 (P < 0.001) and -0.4 ± 0.7 (P = 0.005)] decreased significantly more than in the PY group. An inverse correlation was observed between changes in serum 25(OH)D(3) and FSG (r = -0.208, P = 0.049), FM (r = -0.219, P = 0.038), and HOMA-IR (r = -0.219, P = 0.005). Daily intake of a vitamin D-fortified yogurt drink, either with or without added calcium, improved glycemic status in T2D patients. This trial was registered at clinicaltrials.gov as NCT01229891.

Vitamin D Deficiency in Obese Children and Its Relationship to Insulin Resistance and Adipokines

Low-serum concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with insulin resistance in adults. Less data are available in pediatric populations. Serum 25(OH)D serum concentrations were assessed in 125 obese and 31 nonobese children (age 11.9 ± 2.7 y, range 6–16 y, 49% male) living in Bonn, Germany. The relationship between 25(OH)D, measured by liquid chromatography-tandem mass spectrometry, and measures of insulin sensitivity and adipokines adiponectin and resistin were analyzed. Seventy-six % of subjects were 25(OH)D deficient (<20 ng/mL). Higher insulin, homeostasis model assessment-insulin resistance (HOMA-IR r = −0.269, P = 0.023), and hemoglobin A1c (HbA1c) as well as lower quantitative insulin-sensitivity check index (QUICKI r = 0.264, P = 0.030) values were found in obese children with lower 25(OH)D concentrations even after adjustment for gender, age, and body mass index. Furthermore, 25(OH)D correlated significantly with adiponectin, but not with resistin. Our results suggest that hypovitaminosis D is a risk factor for developing insulin resistance independent of adiposity.

Vitamin D Status of Infants in Northeastern Rural Bangladesh: Preliminary Observations and a Review of Potential Determinants

Vitamin D deficiency is a global public-health concern, even in tropical regions where the risk of deficiency was previously assumed to be low due to cutaneous vitamin D synthesis stimulated by exposure to sun. Poor vitamin D status, indicated by low serum concentrations of 25-hydroxyvitamin D [25(OH)D], has been observed in South Asian populations. However, limited information is available on the vitamin D status of young infants in this region. Therefore, to gain preliminary insights into the vitamin D status of infants in rural Bangladesh, 25(OH)D was assessed in a group of community-sampled control participants in a pneumonia case-control study in rural Sylhet, Bangladesh (25 degrees N) during the winter dry season (January-February). Among 29 infants aged 1-6 months, the mean 25(OH)D was 36.7 nmol/L [95% confidence interval (CI) 30.2-43.2]. The proportion of infants with vitamin D deficiency defined by 25(OH)D < 25 nmol/L was 28% (95% CI 10-45), 59% (95% CI 40-78) had 25(OH)D < 40 nmol/L, and all were below 80 nmol/L. From one to six months, there was a positive correlation between age and 25(OH)D (Spearman = 0.65; p = 0.0001). Within a larger group of 74 infants and toddlers aged 1-17 months (cases and controls recruited for the pneumonia study), young age was the only significant risk factor for vitamin D deficiency [25(OH)D < 25 nmol/L]. Since conservative maternal clothing practices (i.e. veiling) and low frequency of intake of foods from animal source (other than fish) were common among the mothers of the participants, determinants of low maternal-infant 25(OH)D in Bangladesh deserve more detailed consideration in future studies. In conclusion, the vitamin D status in young infants in rural Sylhet, Bangladesh, was poorer than might be expected based on geographic considerations. The causes and consequences of low 25(OH)D in infancy and early childhood in this setting remain to be established.

Similarities in solar ultraviolet irradiance and other environmental factors may explain much of the family link between uveal melanoma and other cancers

Sir: The recent paper [1], exploring the family history of cancer for persons diagnosed with uveal melanoma (UM) was aimed at elucidating a hypothesis that there may increased risk for some cancers in carriers of yet unidentified UM predisposition genetic alteration. While that is certainly a hypothesis worthy of further study, it has to be acknowledged that a familial predisposition can also be due to shared environmental factors. Dietary factors play a major role in cancer risk in general [2]. In the case of UM it seems that dietary factors may improve the survival rate [3]. Smoking and alcohol consumption increase cancer risk, and the same has recently been found to be true for a low serum concentration of 25-hydroxyvitamin D [25(OH)D]. Solar ultraviolet-B (UVB) radiation is the primary human source of vitamin D [4], and solar UVB dose has been found to be inversely correlated with risk of uveal melanoma based on an ecological study [5]. Nearly all of the cancers among those diagnosed with UM and their first and second degree relatives listed in Table 3 of Abdel-Rahman[1] are vitamin D sensitive [6–10], possibly with the exception of prostate cancer in terms of incidence [11, 12], although vitamin D status plays a role in survival for this cancer [13]. Still, diet and genetics certainly play important roles in risk for prostate cancer risk [12, 14]. Related to this study [1] are investigations of second cancers for persons diagnosed with non-melanoma skin cancer (NMSC). At latitudes below about 35–40 , NMSC is generally inversely correlated with risk of second cancer [8, 15], while at higher latitudes, NMSC seems to be positively correlated with risk of many types of cancer [15]. This finding was tentatively explained in terms of the skin surface exposed to the sun: At lower latitudes, larger skin surfaces are probably exposed, so that more vitamin D is produced [16]. In addition, diet and smoking are risk factors for both NMSC and many internal cancers, further explaining the correlations at higher latitudes [16]. Thus, any study looking for genetic risk factors for a cancer based on second primary cancers or cancers in first and second degree relatives, should also take into account whether environmental risk factors such as diet, smoking, and solar UVB exposure (producing vitamin D) might, at least partly, explain the links.

Vitamin D deficiency and frailty in older Americans

To explore the relation between 25-hydroxyvitamin D deficiency and frailty. Frailty is a multidimensional phenotype that describes declining physical function and a vulnerability to adverse outcomes in the setting of physical stress such as illness or hospitalization. Low serum concentrations of 25-hydroxyvitamin D are known to be associated with multiple chronic diseases such as cardiovascular disease and diabetes, in addition to all cause mortality. Using data from the Third National Health and Nutrition Survey (NHANES III), we evaluated the association between low serum 25-hydroxyvitamin D concentration and frailty, defined according to a set of criteria derived from a definition previously described and validated. Nationally representative survey of noninstitutionalized US residents collected between 1988 and 1994. 25-Hydroxyvitamin D deficiency, defined as a serum concentration <15 ng mL(-1), was associated with a 3.7-fold increase in the odds of frailty amongst whites and a fourfold increase in the odds of frailty amongst non-whites. This association persisted after sensitivity analyses adjusting for season of the year and latitude of residence, intended to reduce misclassification of persons as 25-hydroxyvitamin D deficient or insufficient. Low serum 25-hydroxyvitamin D concentrations are associated with frailty amongst older adults.

HYPOVITAMINOSIS D IN THAILAND WAS ASSOCIATED WITH DECREASED RISK FOR HYPERTENSION: PP.7.274

Background: Low serum concentration of 25-hydroxyvitamin D [25(OH)D] is associated with hypertension. Hypovitaminosis D has been observed in tropical regions, its association with hypertension is unknown. Objective: The purpose of this study was to explore the existence of hypovitamnosis D and its association with hypertension in Thailand. Design: A matched nested case-control study was conducted on participants from a cardiovascular study. Serum 25(OH) D concentrations in 1985 from randomly selected 137 cases and controls were used to determine vitamin D status and calculate the odd ratios (OR) of having hypertension in 1997. Serum 25(OH)D ≤ 28 ng/dL was used as a cutoff value. Cases and controls were matched for age and gender. Body mass index (BMI), HDL, LDL, triglyceride were used as covariates. Results: 36% of the participants had suboptimal 25(OH)D concentration. Controls had a significantly higher proportion of vitamin D deficiency than cases. Adjusted for matching variables, the odd ratios (OR) of having hypertension were marginally significant for hypovitaminosis D (OR, 0.59; 95%CI, 0.35–0.99; p = .05) but statistically significant for higher BMI (OR, 2.07; 95%CI, 1.12–3.83; p = .02). The OR of having hypertension for hypovitaminosis D was slightly attenuated but remained marginally significant after further adjustment for BMI, HDL and triglyceride (OR, 0.58; 95%CI, 0.34–0.99; p = .05). Stepwise regression identified BMI as the only variable of significance in relation to hypertension. Conclusion: Although not a rarity in Thailand, hypovitamonisis D was associated with decreased risk of hypertension in Thais.

Low serum concentrations of 25-hydroxyvitamin D in older persons and the risk of nursing home admission

The prevalence of vitamin D deficiency in nursing home patients is high. We aimed to ascertain whether lower serum 25-hydroxyvitamin D [25(OH)D] concentrations increase the risk of future nursing home admission and early death. We included 1260 independent, community-dwelling persons aged > or =65 y who were participating in the Longitudinal Aging Study Amsterdam (1995-1996). Study outcomes were time to nursing home admission during 6 y of follow-up and time to death until 1 April 2003. Vitamin D deficiency [25(OH)D < 25 nmol/L] and insufficiency [25(OH)D = 25-49.9 nmol/L] were present in 127 (10.1%) and 462 (36.7%) subjects, respectively. During follow-up, 138 subjects (11.0%) were admitted to nursing homes, and 380 subjects (30.2%) died. The risk of nursing home admission for participants with 25(OH)D deficiency was 53 cases per 1000 person-years higher than that for those with high 25(OH)D (> or =75 nmol/L) concentrations (58 compared with 5 cases). After adjustment for potential confounders, the hazard ratio (95% CI) of nursing home admission was 3.48 (1.39, 8.75) for vitamin D-deficient, 2.77 (1.17, 6.55) for vitamin D-insufficient, and 1.92 (0.79, 4.66) for vitamin D-borderline persons as compared with persons with high 25(OH)D (P for trend = 0.002). The results remained after additional adjustment for frailty indicators. Lower 25(OH)D was associated with higher mortality risk, but this association was not significant after adjustment for frailty indicators. Lower serum 25(OH)D concentrations in older persons are associated with a greater risk of future nursing home admission and may be associated with mortality.

Requirement of 25-hydroxyvitamin D in prevention of osteoporosis based on a pathophysiological perspective

Vitamin D insufficiency is one of the risk factors of osteoporosis. Secondary hyperparathyroidism induced by low serum concentration of 25-hydroxyvitamin D (25-D), which is a most important nutritional marker to evaluate vitamin D status, results in bone loss and increase of fracture risk. In this topic, the recent findings related to the circulating concentration of 25-D for the prevention of osteoporosis are reviewed.

Low serum concentrations of 25-hydroxyvitamin D in young adult Japanese women: a cross sectional study

OBJECTIVES: The vitamin D nutrition status of young adult women is unclear, but a recent preliminary report suggested that they may have vitamin D insufficiency. This study assessed the serum concentrations of 25-hydroxyvitamin D (25[OH]D), an index of vitamin D nutrition status, in young adult Japanese women in comparison with those in older women and investigated whether serum 25(OH)D concentrations are associated with other calcium-related hormones and bone mass. METHODS: A cross sectional study of 77 healthy women, age 19 to 66 y, working in nursing homes in Japan was conducted in the winter of 1999 and 2000. The investigation included blood tests, forearm bone mass measurements, and a lifestyle questionnaire. RESULTS: The mean serum 25(OH)D concentration in women younger than 30 y was 34.0 nmol/L (standard deviation [SD] = 11.0) and significantly lower than that in women 30 y and older (50.0 nmol/L, SD = 14.4). The proportion of subjects younger than 30 y who had serum 25(OH)D concentrations less than 30 nmol/L was 42.1% and was significantly higher ( P < 0.001) than the proportion of those 30 y and older (10.3%). There was a weak but significant linear association between serum 25(OH)D concentrations and forearm bone mineral content ( R 2 = 0.114, P = 0.0052) but not between serum 25(OH)D concentrations and bone mineral density. The association held after adjusting for body weight ( R 2 = 0.139, P = 0.0111). Serum intact parathyroid hormone concentrations were within the normal range and not associated with serum 25(OH)D concentrations. CONCLUSIONS: Serum 25(OH)D concentrations in young adult Japanese women (<30 y old) are lower than those of older adult women (30 to 66 y), and lower serum 25(OH)D concentrations are likely associated with lower forearm bone mineral content.

Serum 25-hydroxyvitamin D 3 levels decreased in impaired glucose tolerance and diabetes mellitus

A cross-sectional survey was carried out in a New Zealand Polynesian and Caucasian workforce of 5677 staff aged 40–64 years to determine whether serum concentrations of 25-hydroxyvitamin D 3 are altered in people with newly diagnosed diabetes mellitus and impaired glucose tolerance (IGT). Serum 25-hydroxyvitamin D 3 concentration was significantly lower in newly detected cases with diabetes and IGT ( n = 238) compared with controls individually matched by sex, age (± 2 years), ethnicity, and date of interview (mean (S.D.): 69 (31) vs. 76 (34) nmol/l; P = 0.0016). Among controls, serum concentrations were significantly lower in Maori (mean (S.E.) = 65 (5) nmol/l; P = 0.0013) and Pacific Islanders (59 (4) nmol/l; P = 0.0001) compared with Europeans (82 (3) nmol/l), after adjusting for age, sex, and time of year. We conclude that diabetes and IGT are associated with low serum concentrations of 25-hydroxyvitamin D 3 and that low concentrations of this hormone in New Zealand Polynesians may partly explain their increased prevalence of diabetes/IGT compared with Europeans.