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1.
Experimental data suggest a protective effect of vitamin D on breast cancer; however, epidemiologic results remain inclusive. With a Chinese population-based case-control study and meta-analysis of the observational studies, we here systematically evaluated the association of blood 25(OH)D level and breast cancer risk. With 593 breast cancer cases and 580 cancer-free controls from Shanghai, China, we found that 80% of the normal women had severe vitamin D deficiency (less than 20 ng/mL) and 15.2% had mild deficiency (20 to 30 ng/mL) and only 4.8% of women had sufficient vitamin D level (>30 ng/mL) while the proportion was 96.1%, 3.2% and 0.7% respectively for the breast cancer patients. Compared to those with the lowest quartile of plasma 25(OH)D level, women with highest quartile 25(OH)D level showed a significant decreased breast cancer risk (Q4 vs.Q1: OR = 0.10, 95% CI = 0.06–0.15) and every 1 ng/ml increment of plasma 25(OH)D level led to a 16% lower odds of breast cancer (OR = 0.84, 95% CI = 0.81–0.87; P<0.001). From the meta-analysis of the observational studies, we found that women with highest quantile of blood 25(OH)D level was associated with a significantly reduced breast cancer risk compared to those with lowest quantile of blood 25(OH)D level for the 11 nested case-control and retrospective studies (pooled OR = 0.86, 95% CI = 0.75–1.00) and 10 case-control studies (7 population based, OR = 0.35, 95% CI = 0.24–0.52; 3 hospital based, OR = 0.08, 95% CI = 0.02–0.33). These results suggest that vitamin D may have a chemo-preventive effect against breast cancer.  相似文献   

2.

Background

Interpretation of parathyroid hormone (iPTH) requires knowledge of vitamin D status that is influenced by season.

Objective

Characterize the temporal relationship between 25-hydroxyvitamin D3 levels [25(OH)D3] and intact iPTH for several seasons, by gender and latitude in the U.S. and relate 25-hydrovitamin D2 [25(OH)D2] levels with PTH levels and total 25(OH)D levels.

Method

We retrospectively determined population weekly-mean concentrations of unpaired [25(OH)D2 and 25(OH)D3] and iPTH using 3.8 million laboratory results of adults. The 25(OH)D3 and iPTH distributions were normalized and the means fit with a sinusoidal function for both gender and latitudes: North >40, Central 32–40 and South <32 degrees. We analyzed PTH and total 25(OH)D separately in samples with detectable 25(OH)D2 (≥4 ng/mL).

Findings

Seasonal variation was observed for all genders and latitudes. 25(OH)D3 peaks occurred in September and troughs in March. iPTH levels showed an inverted pattern of peaks and troughs relative to 25(OH)D3, with a delay of 4 weeks. Vitamin D deficiency and insufficiency was common (33% <20 ng/mL; 60% <30 ng/mL) as was elevated iPTH levels (33%>65 pg/mL). The percentage of patients deficient in 25(OH)D3 seasonally varied from 21% to 48% and the percentage with elevated iPTH reciprocally varied from 28% to 38%. Patients with detectable 25(OH)D2 had higher PTH levels and 57% of the samples with a total 25(OH)D > 50 ng/mL had detectable 25(OH)D2.

Interpretation

25(OH)D3 and iPTH levels vary in a sinusoidal pattern throughout the year, even in vitamin D2 treated patients; 25(OH)D3, being higher in the summer and lower in the winter months, with iPTH showing the reverse pattern. A large percentage of the tested population showed vitamin D deficiency and secondary hyperparathyroidism. These observations held across three latitudinal regions, both genders, multiple-years, and in the presence or absence of detectable 25(OH)D2, and thus are applicable for patient care.  相似文献   

3.
Vitamin D protects against cognitive decline in animals but evidence in humans has been inconsistent. Fibroblast growth factor 23 (FGF23) is a hormone that inhibits vitamin D activation yet few studies examined whether FGF23 is associated with cognitive impairment. The objective of this study was to examine associations of 25(OH)D and FGF23 with incident cognitive impairment in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a cohort of black and white adults ≥45 years old. FGF23 and 25(OH)D were measured in 474 incident impairment cases and 561 controls. In multivariable-adjusted models, there were no significant associations of FGF23 with incident cognitive impairment. In analyses using clinically-relevant categories of 25(OH)D (< 20 ng/ml, 20–29.9 ng/ml, ≥30 ng/ml), there was no statistically significant association of lower 25(OH)D concentrations with odds of incident cognitive impairment in models adjusted for demographic, clinical, and laboratory variables and season of blood draw (tertile 1 [≥30 ng/ml] reference; tertile 2 [20–29.9 ng/ml], odds ratio [OR] 0.96, 95%CI 0.67, 1.38; tertile 3 [<20 ng/ml] OR 1.26, 95%CI 0.83, 1.91). When 25(OH)D was modeled as race-specific tertiles, there were no significant associations of 25(OH)D with incident cognitive impairment in whites, whereas lower 25(OH)D was associated with higher odds in blacks (tertile 1 [>23 ng/ml] reference; tertile 2 [15–23 ng/ml], OR 2.96, 95%CI 1.48,5.94; tertile 3 [<15 ng/ml] OR 2.40, 95%CI 1.07,5.40) in the fully adjusted model. In this cohort of older adults, lower race-specific tertiles of 25(OH)D were associated with higher incidence of cognitive impairment in black individuals but not white individuals. These data suggest that treating low 25(OH)D may be a novel strategy for addressing racial disparities in neurocognitive outcomes.  相似文献   

4.
Vitamin D plays an increasingly recognized role in the innate and adaptive immune response to infection. Based on demonstrated roles in up-regulating innate immunity, decreasing inflammation, and reducing the severity of disease in illnesses such as tuberculosis and influenza, we hypothesized that poor vitamin D status would be associated with severe malaria. We measured 25-hydroxyvitamin D [25(OH)D] by immunoassay in a sample of Ugandan children aged 18 months –12 years with severe malaria (cerebral malaria or severe malarial anemia, n = 40) and in healthy community children (n = 20). Ninety-five percent of children with severe malaria (n = 38) and 80% of control children (n = 16) were vitamin D-insufficient [plasma 25(OH)D <30 ng/mL]. Mean plasma 25(OH)D levels were significantly lower in children with severe malaria than in community children (21.2 vs. 25.3 ng/mL, p = 0.03). Logistic regression revealed that for every 1 ng/mL increase in plasma 25(OH)D, the odds of having severe malaria declined by 9% [OR = 0.91 (95% CI: 0.84, 1.0)]. These preliminary results suggest that vitamin D insufficiency may play a role in the development of severe malaria. Further prospective studies in larger cohorts are indicated to confirm the relationship of vitamin D levels to severity of malaria infection and to investigate causality.  相似文献   

5.

Background

Few studies have investigated vitamin D status in association with modifiable lifestyle factors and clinical characteristics among breast cancer patients, with no studies among Chinese women, who may be at higher risk of vitamin D deficiency. We aimed to evaluate circulating 25-hydroxyvitamin D (25(OH)D) levels in association with clinical and lifestyle factors among 1,940 Chinese breast cancer patients.

Methods

Participants included breast cancer cases aged 22–77 from a population-based case-control study conducted in Shanghai, China during 1996–1998 (n = 1,044) and 2002–2005 (n = 896). Circulating 25(OH)D levels were measured in plasma samples (95% collected ≤6 months post-diagnosis). Prevalence ORs and 95% CIs were derived from multinomial logistic regression models, adjusting for age, season, and other factors.

Results

About 23% and 48% of women were vitamin D deficient (<30 nmol/L) or insufficient (30–50 nmol/L), respectively. Tumor characteristics were not associated with vitamin D status. Higher BMI was associated with increased odds of vitamin D deficiency (ORs (95% CIs): 1 (reference), 1.12 (0.85,1.47), and 1.57 (1.02,2.42), for <23, 23–<27.5, and ≥27.5 kg/m2, respectively, Ptrend <0.06). Total physical activity was associated with reduced odds of vitamin D deficiency (ORs (95% CIs):1 (reference), 0.84 (0.59,1.20), 0.65 (0.45,0.93), and 0.69 (0.48,1.00), for <7.65, 7.65–<10.6, 10.6–<13.5, ≥13.5 MET-hours/day, respectively, Ptrend <0.02). Smoking was associated with vitamin D insufficiency and deficiency (ORs (95% CIs): 2.50 (1.07,5.84) and 2.78 (1.11,6.95), respectively).

Conclusions

In the largest study to date, the prevalence of low vitamin D status was high among Chinese breast cancer patients and associated with higher BMI, smoking, and lower physical activity. Our findings support careful monitoring of vitamin D status and recommendations for supplementation and other lifestyle modifications that may improve vitamin D status in breast cancer patients.  相似文献   

6.

Background

It is well established that low levels of 25(OH) Vitamin D (<30 ng/dL) are a common finding world over, affecting over a billion of the global population. Our primary objective was to determine the prevalence of vitamin D deficiency and insufficiency in the asymptomatic adult population of Karachi, Pakistan and the demographic, nutritional and co-morbidity characteristics associated with serum vitamin D levels.

Methods

A cross-sectional population survey was conducted at two spaced out densely populated areas of the city. Serum levels of 25OHVitamin D were measured and GFR as renal function was assessed by using 4 variable MDRD formula.

Results

Our sample of 300 had a median age of 48(interquartile range 38–55) years. The median level of serum vitamin D was 18.8 (IQ range 12.65–24.62) ng/dL. A total of 253 (84.3%) respondents had low levels (<30 ng/dL) of 25OH vitamin D. Serum PTH and vitamin D were negatively correlated (r = −0.176, p = 0.001). The median PTH in the vitamin D sufficiency group was 38.4(IQ range28.0–48.8)pg/mL compared with 44.4(IQ range34.3–56.8) pg/mL in the deficiency group (p = 0.011).The median serum calcium level in the sample was 9.46(IQ range 9.18–9.68) ng/dL. Low serum levels of vitamin D were not associated with hypertension (p = 0.771) or with an elevated spot blood pressure (p = 0.164).In our sample 75(26%) respondents had an eGFR corresponding to stage 2 and stage 3 CKD. There was no significant correlation between levels of vitamin D and eGFR (r = −0.127, p-value = 0.277).Respondents using daily vitamin D supplements had higher 25 OH vitamin D levels (p-value = 0.021).

Conclusion

We observed a high proportion of the asymptomatic adult population having low levels of vitamin D and subclinical deterioration of eGFR. The specific cause(s) for this observed high prevalence of low 25OH vitamin D levels are not clear and need to be investigated further upon.  相似文献   

7.
Sclerostin is a protein secreted by osteocytes that acts as an inhibitor of bone formation. It has been shown that physical activity affects sclerostin concentration and thus bone remodelling. The aim of the study was to evaluate serum concentrations of sclerostin, selected bone turnover markers (PTH, P1NP), 25(OH)D3 and the intake of calcium and vitamin D in physically active versus sedentary men. A total of 59 healthy men aged 17-37 were enrolled in the study (43 athletes and 16 non-athletes). The mean sclerostin concentration in the group of athletes (A) was significantly higher than in non-athletes (NA) (35.3±8.9 vs 28.0±5.6 pmol·l-1, p= 0.004). A compared with NA had higher concentrations of P1NP (145.6±77.5 vs 61.2±22.3 ng·ml-1, p= <0.0001) and 25(OH)D3 (16.9±8.4 vs 10.3±4.3 ng·ml-1, p= 0.004) and lower concentrations of PTH (25.8±8.3 vs 38.2±11.5 pg·ml-1, p= <0.0001). Vitamin D deficiency was found in 77% of A and 100% of NA. A and NA had similar daily energy intake. They did not differ as to the intake of calcium and vitamin D. We observed a negative correlation between the serum concentrations of sclerostin and calcium in the studied subjects. Our results suggest that regular, long-lasting physical training may be associated with higher concentration of sclerostin. It seems that increased sclerostin is not related to other bone turnover markers (PTH, P1NP).  相似文献   

8.

Background

To evaluate effects of neoadjuvant chemotherapy on the bone turnover markers of preoperational breast cancer patients.

Methods

Forty-one breast cancer patients (29 premenopausal and 12 postmenopausal) and 60 healthy women (30 premenopausal and 30 postmenopausal) aged 30-64 years, were evaluated for their bone status. Serum levels of the bone formation markers PINP and BAP, as well as the resorption markers ICTP and β-Crosslaps in addition to E2, FSH, 25(OH)D and PTH were measured at the initial diagnosis and at 24 hours after each four chemotherapy cycles. BMD T-scores were determined in 12 patients 6 months after the neoadjuvant chemotherapies.

Results

The baseline levels of both bone formation and resorption markers in premenopausal patients were higher than in premenopausal healthy women (p<0.05), while no statistic difference was observed between postmenopausal patients and postmenopausal healthy women. Regardless of the menopausal status, chemotherapy increased the ICTP and β-Crosslaps levels (p<0.05), but decreased the BAP and PINP levels (p<0.05), the later one significantly more with Taxane medication (p<0.01, p<0.05). Chemotherapy caused significant decreases of 25(OH)D levels in premenopausal (p<0.01) and postmenopausal (p<0.05) patients, however, did not affect the PTH concentrations. In premenopausal patients the E2 level decreased, while the FSH level increased after chemotherapy (p<0.05). Patients with pronounced ICTP and β-Crosslaps combined with reduced BAP and PINP serum concentrations after neoadjuvant chemotherapies were prone to develop osteoporosis 6 month later.

Conclusions

Neoadjuvant chemotherapy appeared to promote bone resorption and inhibit bone formation in both postmenopausal and premenopausal early-stage breast patients.  相似文献   

9.
An increasing number of studies suggest that vitamin D deficiency during pregnancy is associated with multiple adverse health outcomes in mothers, neonates and children. There are no representative country data available on vitamin D status of pregnant women in Europe. The aim of this study was to estimate the prevalence of vitamin D deficiency among Belgian pregnant women and to assess the determinants of vitamin D status in the first and third trimester of pregnancy. The women were selected via a multi-stage proportionate-to-size sampling design. Blood samples were collected and a questionnaire was completed face-to-face. 55 obstetric clinics were randomly selected and 1311 pregnant women participated in the study. The median serum 25-hydroxyvitamin D [25-(OH)D] concentration was significantly lower in the first trimester (20.4 ng/ml) than in third trimester (22.7 ng/ml). Of all women, 74.1% (95%CI = 71.8–76.5%) were vitamin D insufficient (25-(OH)D <30 ng/ml), 44.6% (95%CI = 41.9–47.3%) were vitamin D deficient (25-(OH)D <20 ng/ml), while 12.1% (95%CI = 10.3–13.8%) were severely vitamin D deficient (25-(OH)D <10 ng/ml). Of all women included, 62.0% reported taking vitamin D-containing multivitamins, of which only 24.2% started taking those before pregnancy. The risk of vitamin D deficiency (25-(OH)D <20 ng/ml) was significantly higher for less educated women and women who reported not going on holidays to sunny climates. The risk of severe vitamin D deficiency (25-(OH)D <10 ng/ml) decreased for women who reported alcohol consumption during pregnancy, decreased with more frequent use of sunscreen lotion and increased for smokers and women who reported preference for shadow. In conclusion, vitamin D deficiency is highly prevalent among pregnant women in Belgium and this raises concerns about the health consequences for the mother and the offspring. A targeted screening strategy to detect and treat women at high risk of severe vitamin D deficiency is needed in Belgium and in Europe.  相似文献   

10.

Objective

To investigate the association between serum 25-hydroxyvitamin D [25(OH)D] level and history of community-acquired pneumonia (CAP).

Patients and Methods

We identified 16,975 individuals (≥17 years) from the third National Health and Nutrition Examination Survey (NHANES III) with documented 25(OH)D levels. To investigate the association of 25(OH)D with history of CAP in these participants, we developed a multivariable logistic regression model, adjusting for demographic factors (age, sex, race, poverty-to-income ratio, and geographic location), clinical data (body mass index, smoking status, asthma, chronic obstructive pulmonary disease, congestive heart failure, diabetes mellitus, stroke, chronic kidney disease, neutropenia, and alcohol consumption), and season. Locally weighted scatterplot smoothing (LOWESS) was used to depict the relationship between increasing 25(OH)D levels and the cumulative frequency of CAP in the study cohort.

Results

The median [interquartile range (IQR)] serum 25(OH)D level was 24 (IQR 18–32) ng/mL. 2.1% [95% confidence interval (CI): 1.9–2.3] of participants reported experiencing a CAP within one year of their participation in the national survey. After adjusting for demographic factors, clinical data, and season, 25(OH)D levels <30 ng/mL were associated with 56% higher odds of CAP [odds ratio 1.56; 95% confidence interval: 1.17–2.07] compared to levels ≥30 ng/mL. LOWESS analysis revealed a near linear relationship between vitamin D status and the cumulative frequency of CAP up to 25(OH)D levels around 30 ng/mL.

Conclusion

Among 16,975 participants in NHANES III, 25(OH)D levels were inversely associated with history of CAP. Randomized controlled trials are warranted to determine the effect of optimizing vitamin D status on the risk of CAP.  相似文献   

11.

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.  相似文献   

12.

Background

Hypocalcemia is a frequent abnormality that has been associated with disease severity and outcome in hospitalized foals. However, the pathogenesis of equine neonatal hypocalcemia is poorly understood. Hypovitaminosis D in critically ill people has been linked to hypocalcemia and mortality; however, information on vitamin D metabolites and their association with clinical findings and outcome in critically ill foals is lacking. The goal of this study was to determine the prevalence of vitamin D deficiency (hypovitaminosis D) and its association with serum calcium, phosphorus, and parathyroid hormone (PTH) concentrations, disease severity, and mortality in hospitalized newborn foals.

Methods and Results

One hundred newborn foals ≤72 hours old divided into hospitalized (n = 83; 59 septic, 24 sick non-septic [SNS]) and healthy (n = 17) groups were included. Blood samples were collected on admission to measure serum 25-hydroxyvitamin D3 [25(OH)D3], 1,25-dihydroxyvitamin D3 [1,25(OH) 2D3], and PTH concentrations. Data were analyzed by nonparametric methods and univariate logistic regression. The prevalence of hypovitaminosis D [defined as 25(OH)D3 <9.51 ng/mL] was 63% for hospitalized, 64% for septic, and 63% for SNS foals. Serum 25(OH)D3 and 1,25(OH) 2D3 concentrations were significantly lower in septic and SNS compared to healthy foals (P<0.0001; P = 0.037). Septic foals had significantly lower calcium and higher phosphorus and PTH concentrations than healthy and SNS foals (P<0.05). In hospitalized and septic foals, low 1,25(OH)2D3 concentrations were associated with increased PTH but not with calcium or phosphorus concentrations. Septic foals with 25(OH)D3 <9.51 ng/mL and 1,25(OH) 2D3 <7.09 pmol/L were more likely to die (OR=3.62; 95% CI = 1.1-12.40; OR = 5.41; 95% CI = 1.19-24.52, respectively).

Conclusions

Low 25(OH)D3 and 1,25(OH)2D3 concentrations are associated with disease severity and mortality in hospitalized foals. Vitamin D deficiency may contribute to a pro-inflammatory state in equine perinatal diseases. Hypocalcemia and hyperphosphatemia together with decreased 1,25(OH)2D3 but increased PTH concentrations in septic foals indicates that PTH resistance may be associated with the development of these abnormalities.  相似文献   

13.
《Endocrine practice》2008,14(1):10-17
ObjectiveTo investigate the efficacy of cholecalciferol (vitamin D3) in raising serum 25-hydroxyvitamin D (25[OH)]D) levels and reducing parathyroid hormone (PTH) levels in patients with chronic kidney disease (CKD).MethodsIn this double-blind, randomized controlled pilot study, participants with CKD stage 3 and 4 (estimated glomerular filtration rate, 15-59 mL/min/1.73 m2), vitamin D insufficiency (serum 25[OH]D < 30 ng/mL), and serum intact PTH levels > 70 pg/mL were randomly assigned to receive either 50 000 IU of cholecalciferol or placebo once weekly for 12 weeks. Primary outcomes (25[OH]D and PTH levels) were measured at baseline, week 6, and week 12. Secondary outcomes (1,25-dihydroxvitamin D and bone turnover markers) were measured at baseline and week 12. Because of skewed data distribution, statistical analyses were performed on a logarithmic scale. The difference between the group means was exponentiated to provide the geometric mean ratio. A linear mixed model using an unstructured variance-covariance matrix was used to examine change in the primary and secondary outcomes over time.ResultsGeometric mean serum 25(OH)D concentrations of the study groups were similar at baseline (P = .77). At week 6, a significant difference between the treatment and placebo groups was detected (P = .001); this difference was maintained at week 12 (P = .002). Among cholecalciferol- treated participants, serum 25(OH)D concentration increased on average from 17.3 ng/mL (95% confidence interval [CI], 11.8-25.2) at baseline to 49.4 ng/mL (95% CI, 33.9-72.0) at week 12. As-treated analysis indicated a trend toward lower PTH levels among cholecalciferol-treated participants (P = .07).ConclusionWeekly cholecalciferol supplementation appears to be an effective treatment to correct vitamin D status in patients with CKD. (Endocr Pract. 2008;14:10-17)  相似文献   

14.

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.  相似文献   

15.
BackgroundVitamin D deficiency is common in pregnant women, but an optimal serum vitamin D level during pregnancy has not been determined and remains an area of active research. Vitamin D data from large populations of pregnant Chinese women are still limited.ObjectiveTo evaluate the vitamin D status of women in Eastern China during the second trimester of pregnancy.MethodsA hospital-based, cross-sectional, observational study. Serum 25-hydroxyvitamin D [25(OH)D] concentration was measured in samples from 5823 pregnant women in Wuxi City, China (latitude: 31.5o N), from January 2011 to June 2012.ResultsThe median serum 25(OH)D concentration was 34.0 nmol/L [2.5 nmol/L 25(OH)D = 1 ng/mL 25(OH)D]. Vitamin D deficiency [defined as 25(OH)D < 30 nmol/L according to the Institute of Medicine (National Academy of Sciences, Washington, D.C., USA)] or inadequacy [25(OH)D of 30–49.9 nmol/L] was identified in 40.7% and 38.0% of the women, respectively. Only 0.9% had a 25(OH)D level ≥ 80.0 nmol/L, which is the concentration recommended as adequate by the Endocrine Society (Washington, D.C., USA). Compared with older women, younger women were more likely to be deficient in vitamin D. There were significant differences in the 25(OH)D levels according to season. The 25(OH)D levels reached peak values in September and were correlated with (r = 0.337, P < 0.001), and fluctuated with, average monthly air temperatures.ConclusionsThere is a high prevalence of Vitamin D deficiency among pregnant Chinese women, and 25(OH)D levels varied according to season and air temperature. The results of this study also suggest that currently there is a big gap between the levels of Vitamin D detected in pregnant Chinese women and the levels recommended by the Endocrine Society.  相似文献   

16.

Objective

Considering that epidemiological studies show that suicide rates in many countries are highest in the spring when vitamin D status is lowest, and that low vitamin D status can affect brain function, we sought to evaluate if a low level of 25-hydroxyvitamin D [25(OH)D] could be a predisposing factor for suicide.

Method

We conducted a prospective, nested, case-control study using serum samples stored in the Department of Defense Serum Repository. Participants were previously deployed active duty US military personnel (2002–2008) who had a recent archived serum sample available for analysis. Vitamin D status was estimated by measuring 25(OH) D levels in serum samples drawn within 24 months of the suicide. Each verified suicide case (n = 495) was matched to a control (n = 495) by rank, age and sex. We calculated odds ratio of suicide associated with categorical levels (octiles) of 25(OH) D, adjusted by season of serum collection.

Findings

More than 30% of all subjects had 25(OH)D values below 20 ng/mL. Although mean serum 25(OH)D concentrations did not differ between suicide cases and controls, risk estimates indicated that subjects in the lowest octile of season-adjusted 25(OH)D (<15.5 ng/mL) had the highest risk of suicide, with subjects in the subsequent higher octiles showing approximately the same level of decreased risk (combined odds ratio compared to lowest octile  = 0.49; 95% C.I.: 0.315–0.768).

Conclusions

Low vitamin D status is common in active duty service members. The lowest 25(OH)D levels are associated with an increased risk for suicide. Future studies could determine if additional sunlight exposure and vitamin D supplementation might reduce suicide by increasing 25(OH) D levels.  相似文献   

17.

Objective

The aim of our study was to elucidate the pathophysiology of systemic sclerosis-related osteoporosis and the prevalence of vertebral fragility fracture in postmenopausal women with systemic sclerosis (SSc).

Methodology

Fifty-four postmenopausal women with scleroderma and 54 postmenopausal controls matched for age, BMI, and smoking habits were studied. BMD was measured by dual energy-x-ray absorptiometry at spine and femur, and by ultrasonography at calcaneus The markers of bone turnover included serum osteocalcin and urinary deoxypyridinoline. All subjects had a spine X-ray to ascertain the presence of vertebral fractures.

Results

bone mineral density at lumbar spine (BMD 0.78±0.08 vs 0.88±0.07; p<0,001), femoral neck (BMD: 0.56±0.04 vs 0.72±0.07; p<0,001) and total femur (BMD: 0.57±0.04 vs 0.71±0.06; p<0,001) and ultrasound parameter at calcaneus (SI: 80.10±5.10 vs 94.80±6.10 p<0,001) were significantly lower in scleroderma compared with controls; bone turnover markers and parathyroid hormone level were significantly higher in scleroderma compared with controls, while serum of 25(OH)D3 was significantly lower. In scleroderma group the serum levels of 25(OH)D3 significantly correlated with PTH levels, BMD, stiffness index and bone turnover markers. One or more moderate or severe vertebral fractures were found in 13 patients with scleroderma, wherease in control group only one patient had a mild vertebral fracture.

Conclusion

Our data shows, for the first time, that vertebral fractures are frequent in subjects with scleroderma, and suggest that lower levels of 25(OH)D3 may play a role in the risk of osteoporosis and vertebral fractures.  相似文献   

18.
Background:Irisin as an exercise-induced myokine was proposed to improve bone health. This study investigated the role of serum irisin (s-irisin) in patients with osteoporosis (OP) through correlating to most biological bone markers and oxidative stress.Methods:A cross-sectional study recruited an eligible 175 postmenopausal women at Al-Hussien Teaching Hospital, Iraq. They were scanned by DEXA and stratified into two groups based on T-score; the first 95 patients as control group (GI) with −1 ≤ T-score and the second 80 patients as cases group (GII) with T-score ≤ −2.5. Demographic criteria were age, bone mineral density (BMD, g/cm2) and T-score. Serum irisin, total serum calcium (s-calcium), serum inorganic phosphate (s-phosphate), serum alkaline phosphatase (s-ALP), serum 25 [OH] vitamin D, the serum parathyroid hormone (s-PTH), serum Carboxy terminal collagen crosslinks (CTx), serum procollagen type I C-termidnal peptide (s-PICP), serum malondialdehyde (s-MDA) and serum superoxide dismutase (s-SOD) were collected from blood samples.Results:Serum irisin were 31.84 ± 2.65 vs. 20.88 ± 2.71 ng/mL for control and trial groups, respectively. Lower levels of BMD, T-score, 25 [OH] vitamin D, and s-irisin along with a higher serum levels of PTH, CTx, PICP, MDA and SOD were observed in patients with osteoporosis. All parameters were statistically meaningful upon correlation (p< 0.0001), except age and s-calcium (p= 0.0088 and p= 0.187, respectively).Conclusion:The results showed that, a significantly lower serum irisin levels among osteoporosis women, was intimately correlated to most bone turnover markers and it can be considered as encouraging results for clinical application in prediction and treatment of osteoporosis.Key Words: Bone turnover markers, DEXA scan, Irisin, T-score, BMD, osteoporosis, post-menopause  相似文献   

19.

Objective

In recent years, vitamin D has been shown to possess a wide range of immunomodulatory effects. Although there is extensive amount of research on vitamin D, we lack a comprehensive understanding of the prevalence of vitamin D deficiency or the mechanism by which vitamin D regulates the human immune system. This study examined the prevalence and correlates of vitamin D deficiency and the relationship between vitamin D and the immune system in healthy individuals.

Methods

Healthy individuals (n = 774) comprised of European-Americans (EA, n = 470), African–Americans (AA, n = 125), and Native Americans (NA, n = 179) were screened for 25-hydroxyvitamin D [25(OH)D] levels by ELISA. To identify the most noticeable effects of vitamin D on the immune system, 20 EA individuals with severely deficient (<11.3 ng/mL) and sufficient (>24.8 ng/mL) vitamin D levels were matched and selected for further analysis. Serum cytokine level measurement, immune cell phenotyping, and phosphoflow cytometry were performed.

Results

Vitamin D sufficiency was observed in 37.5% of the study cohort. By multivariate analysis, AA, NA, and females with a high body mass index (BMI, >30) demonstrate higher rates of vitamin D deficiency (p<0.05). Individuals with vitamin D deficiency had significantly higher levels of serum GM-CSF (p = 0.04), decreased circulating activated CD4+ (p = 0.04) and CD8+ T (p = 0.04) cell frequencies than individuals with sufficient vitamin D levels.

Conclusion

A large portion of healthy individuals have vitamin D deficiency. These individuals have altered T and B cell responses, indicating that the absence of sufficient vitamin D levels could result in undesirable cellular and molecular alterations ultimately contributing to immune dysregulation.  相似文献   

20.

Background

Previous studies exploring the association between 25[OH]D levels and mortality in adults with and without kidney disease utilized 25[OH]D thresholds that have recently been scrutinized by the Institute of Medicine Committee to Review Dietary References Intakes for Vitamin D and Calcium.

Objective

We explored all-cause mortality rates across the spectrum of 25[OH]D levels over an eighteen-year follow-up among adults with and without an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2.

Design

The study included 1,097 U.S. adults with eGFR <60 ml/min/1.73 m2 and 14, 002 adults with eGFR ≥60 ml/min/1.73 m2. Mortality rates and rate ratios (RR) across 25[OH]D groups were calculated with Poisson regression and restricted cubic splines while adjusting for covariates.

Results

Prevalence of 25[OH]D levels <30 and <20 ng/ml among adults with eGFR <60 ml/min/1.73 m2 was 76.5% (population estimate 6.2 million) and 35.4% (population estimate 2.9 million), respectively. Among adults with eGFR ≥60 ml/min/1.73 m2, 70.5% had 25[OH]D levels <30 ng/ml (population estimate 132.2 million) while 30.3% had 25[OH]D levels <20 ng/ml (population estimate 56.8 million). Significantly higher mortality rates were noted among individuals with 25[OH]D levels <12 ng/ml compared to referent group (24 to <30 ng/ml): RR1.41 (95% CI 1.17, 1.71) among individuals with eGFR <60 ml/min/1.73 m2 and RR 1.32 (95% CI 1.13, 1.56) among individuals with eGFR ≥60 ml/min/1.73 m2 after adjustment for covariates including co-morbid conditions. Mortality rates were fairly similar across all 25[OH]D groups with levels >20 ng/ml after adjustment for all covariates.

Conclusions

Regardless of presence of eGFR <60 ml/min/1.73 m2, mortality rates across groups with 25[OH]D levels 20–40 ng/ml are similar.  相似文献   

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