Serum 25-Hydroxyvitamin D and Insulin Resistance in Apparently Healthy Adolescents

Purpose

Vitamin D deficiency is a common condition that is associated with diabetes and insulin resistance. However, the association between vitamin D and insulin resistance has not been fully studied, especially in the general adolescent population. Therefore, we assessed the association between serum 25-hydroxyvitamin D [25(OH)D] level and insulin resistance among apparently healthy Korean adolescents.

Methods

A total of 260 (135 male and 125 female) adolescents in a rural high school were assessed for serum 25(OH)D, fasting plasma glucose, and insulin. All of the participants were aged 15 to 16 years old, and without known hypertension or diabetes. Serum 25(OH)D was analyzed both as a continuous and categorical variable in association with insulin resistance. Insulin resistance was estimated by homeostasis model assessment (HOMA-IR). Increased insulin resistance was operationally defined as a HOMA-IR value higher than the sex-specific 75th percentile.

Results

In male adolescents, every 10 ng/ml decrease in 25(OH)D level was associated with a 0.25 unit increase in HOMA-IR (p = 0.003) after adjusting for age and BMI. Compared to those in the highest quartile, male adolescents in the lowest 25(OH)D quartile were at significantly higher risk for insulin resistance: unadjusted odds ratio 4.06 (95% CI, 1.26 to 13.07); age and BMI adjusted odds ratio 3.59 (95% CI, 1.03 to 12.57). However, 25(OH)D level, either in continuous or categorical measure, was not significantly associated with insulin resistance among female adolescents.

Conclusions

This study suggests that serum 25(OH)D level may be inversely associated with insulin resistance in healthy male adolescents.     

Treatment with 50000 IU Vitamin D2 Every Other Week and Effect on Serum 25-Hydroxyvitamin D2, 25-Hydroxyvitamin D3, and Total 25-Hydroxyvitamin D in Aclinical Setting

ObjectiveTo examine the effect of 50 000 IU-vitamin D₂ supplementation in a clinical setting on serum total 25-hydroxyvitamin D (25[OH]D), 25-hydroxyvitamin D₂ (25[OH]D₂), and 25-hydroxyvitamin D₃ (25[OH]D₃).MethodsThis retrospective cohort study was performed in an urban tertiary referral hospital in Boston, Massachusetts. Patients who had been prescribed 50 000 IU vitamin D₂ repletion and maintenance programs were identified through a search of our electronic medical record. Baseline and follow-up total serum 25(OH)D, 25(OH)D₂, and 25(OH)D₃ levels were compared.ResultsWe examined the medical records of 48 patients who had been prescribed 50 000 IU vitamin D₂ in our clinic. Mean ± standard deviation baseline total 25(OH) D was 31.0 ± 10.6 ng/mL and rose to 48.3 ± 13.4 ng/mL after treatment (P <.001). 25(OH)D₂ increased from 4.2 ± 4.3 ng/mL to 34.6 ± 12.3 ng/mL after treatment (P <.001), for an average of 158 days (range, 35-735 days). Serum 25(OH)D3 decreased from 26.8 ± 10.8 ng/mL to 13.7 ± 7.9 ng/mL (P <.001).ConclusionsFifty thousand IU vitamin D₂ repletion and maintenance therapy substantially increases total 25(OH)D and 25(OH)D2 despite a decrease in serum 25(OH)D3. This treatment program is an appropriate and effective strategy to treat and prevent vitamin D deficiency.(Endocr Pract. 2012;18:399-402)     

Serum 25-Hydroxyvitamin D Level and Influenza Vaccine Immunogenicity in Children and Adolescents

Background

Vaccination is an important strategy in the prevention of influenza, but immunologic response to vaccination can vary widely. Recent studies have shown an association between serum 25-hydroxyvitamin D (25[OH]D) levels and immune function. The purpose of this study was to determine if serum 25(OH)D level correlates with influenza vaccine immunogenicity in children and adolescents.

Methods

We conducted a prospective cohort study of children age 3 to 15 years of age vaccinated with trivalent influenza vaccine (A/Brisbane/59/2007[H1N1]-like virus, A/Brisbane/10/2007 [H3N2]-like virus and B/Florida/4/2006-like virus) in Hutterite communities in Alberta, Saskatchewan and Manitoba. Serum 25(OH)D levels were measured at baseline and immunogenicity was assessed using hemagluttination inhibition (HAI) titers done at baseline and 3–5 weeks post vaccination. Logistic regression was used to assess the relationship between serum 25(OH)D level as both a continuous and dichotomous variable and seroprotection, seroconversion, fold increase in geometric mean titer (GMT) and post vaccination titer.

Results

A total of 391 children and adolescents were included in the study and 221 (57% had post-vaccination HAI titers. The median serum 25(OH)D level was 61.0 nmol/L (Interquartile range [IQR] 50.0, 71.0). No relationship was found between serum 25(OH)D level and seroprotection (post-vaccination titer ≥40 and ≥320) or seroconversion (post-vaccination titer ≥40 for participants with pre-vaccine titer <10 or four-fold rise in post-vaccination titer for those with a pre-vaccine titer ≥10).

Conclusion

Serum 25(OH)D level was not associated with influenza vaccine immunogenicity in otherwise healthy children and adolescents. Other strategies to enhance influenza vaccine response should continue to be evaluated in this population.The role of serum 25(OH)D level in vaccine responsiveness in other populations, especially those hyporesponsive to influenza vaccination, requires further study.     

The Relationship Between Serum 25-Hydroxyvitamin D and Glucose Homeostasis in Obese Children and Adolescents in Zhejiang,China

Objective: Evidence of the association between vitamin D, insulin resistance, and oral disposition index (oDI) in obese children and adolescents is limited. To fill this research gap, we measured serum 25-hydroxyvitamin D (25&lsqb;OH]D) levels in obese children and analyzed the relationship between serum 25(OH)D levels and glucose homeostasis.Methods: Altogether, 348 obese and 445 nonobese children and adolescents (age, 6 to 16 years) were enrolled in this study. Obese children were divided into 4 subgroups: normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and combined IFG and IGT (IFG+IGT) according to oral glucose tolerance test results. We measured serum 25(OH)D levels and calculated the homeostasis model assessment (HOMA) of insulin resistance (IR), the whole-body insulin sensitivity index (WBISI), and the disposition index.Results: The levels of 25(OH)D in the obese group were significantly lower than in the nonobese group; serum 25(OH)D level in the NGT subgroup was higher than those of the other 3 subgroups, and it was significantly inversely correlated with logHOMA-IR (r = -0.090; P = .045) and positively correlated with logWBISI and logHOMA-oDI (r = 0.091, P = .049; and r = 0.108, P = .046, respectively). Obese patients with vitamin D deficiency thus have a significantly higher risk of disturbances in glucose metabolism.Conclusion: 25(OH)D deficiency or insufficiency is quite common in obese children and adolescents in Zhejiang, China. Obese patients with 25(OH)D deficiency (<30 nmol/L) are shown to be at higher risk for abnormal glucose metabolism.Abbreviations: 25(OH)D = 25-hydroxyvitamin D ΔI₃₀/ΔG₃₀ = insulinogenic index BMI = body mass index CI = confidence interval HbA_1c = hemoglobin A_1c HOMA = homeostasis model assessment I_F = fasting insulin IFG = impaired fasting glucose IGT = impaired glucose tolerance IR = insulin resistance NGT = normal glucose tolerance oDI = oral disposition index OGTT = oral glucose tolerance test WBISI = whole-body insulin sensitivity index     

Vitamin D Binding Protein Genotype Is Associated with Serum 25-Hydroxyvitamin D and PTH Concentrations,as Well as Bone Health in Children and Adolescents in Finland

Vitamin D binding protein (DBP)/group-specific component (Gc), correlates positively with serum vitamin D metabolites, and phenotype influences serum 25-hydroxyvitamin D (S-25(OH)D) concentration. The protein isoform has been associated with decreased bone mineral density (BMD) and increased fracture risk. We examined the role of GC genotypes in S-25(OH)D status and BMD in 231 Finnish children and adolescents aged 7−19 yr. BMD was measured with DXA from lumbar spine (LS), total hip, and whole body, and for 175 subjects, radial volumetric BMD was measured with pQCT. Background characteristic and total dietary intakes of vitamin D and calcium were collected. The concentrations of 25(OH)D, parathyroid hormone (PTH), calcium and other markers of calcium homeostasis were determined from blood and urine. Genotyping was based on single-nucleotide polymorphism (rs4588) in the GC gene. The genotype distribution was: GC 1/1 68%, GC 1/2 26% and GC 2/2 6%. A significant difference emerged in 25(OH)D and PTH concentrations between the genotypes, (p = 0.001 and 0.028 respectively, ANCOVA). There was also a linear trend in: Gc 2/2 had the lowest 25(OH)D and PTH concentrations (p = 0.025 and 0.012, respectively). Total hip bone mineral content was associated with GC genotype (BMC) (p = 0.05, ANCOVA) in boys. In regression analysis, after adjusting for relevant covariates, GC genotype was associated with LS BMC and strength and strain index (SSI) Z-score in both genders, and LS BMD in boys. In conclusion, the present study demonstrates the association between GC genotypes and S-25(OH)D and PTH concentrations. The results show the influence of DBP genetic variation on bone mass accrual in adolescence.     

Low Free (But Not Total) 25-Hydroxyvitamin D Levels in Subjects with Normocalcemic Hyperparathyroidism

Objective: Normocalcemic primary hyperparathyroidism (NPHPT) is characterized by elevated parathyroid hormone (PTH) levels with persistently normal calcium levels. The diagnosis of NPHPT assumes the absence of secondary causes of elevated PTH levels. The objective of the current study was to examine levels of free 25-hydroxyvitamin D (25&lsqb;OH]D) in NPHPT subjects and healthy controls.Methods: Ten NPHPT subjects and 20 controls who were age, sex, race, and body mass index (BMI) matched were examined. The diagnosis of NPHPT was made if subjects had (1) a serum calcium level of 8.6 to 10.4 mg/dL, total 25(OH)D 30 to 40 ng/mL, and intact PTH (iPTH) ≥66 pg/mL; and (2) normal renal and liver function. Serum total 25(OH)D levels were measured by radioimmunoassay, and free 25(OH)D levels were determined using an enzyme-linked immunoassay.Results: Mean age of NPHPT subjects was 59.9 ± 5.4 years, and mean BMI was 28.4 ± 2.3 kg/m², which was not significantly different from the mean age and BMI of the control subjects. Mean total 25(OH)D level was 31.9 ± 1.7 ng/mL in NPHPT subjects and did not differ from that of the controls (32.7 ± 3.3 ng/mL; P = .52). However, mean free 25(OH)D was 5.0 ± 0.9 pg/mL in NPHPT subjects, which was 20% lower compared to the mean of the controls (6.2 ± 1.3 pg/mL; P = .013). Serum iPTH levels were inversely correlated with levels of measured free 25(OH)D (r = -0.42; P<.05) but did not correlate with levels of total 25(OH)D (r = -0.14; P>.10).Conclusion: Measured free 25(OH)D levels are lower in NPHPT subjects than in healthy control subjects. We suggest that some NPHPT subjects may actually have secondary hyperparathyroidism based on their free 25(OH) D levels.Abbreviations: 25(OH)D = 25-hydroxyvitamin D; BMI = body mass index; CV = coefficient of variation; DBP = vitamin D–binding protein; iPTH = intact parathyroid hormone; NPHPT = normocalcemic primary hyperparathyroidism     

Prognostic Value of Serum 25-Hydroxyvitamin D in Patients with Stroke

We aimed to evaluate the association between 25-hydroxyvitamin D [25(OH) D] levels and both clinical severity at admission and outcome at discharge in patients with acute ischemic stroke (AIS). From June 2012 to October 2013, consecutive first-ever AIS patients admitted to the Department of Emergency of The Fourth Affiliated Hospital of Harbin Medical University, China were identified. Clinical information was collected. Serum 25(OH) D levels were measured at baseline. Stroke severity was assessed at admission using the National Institutes of Health Stroke Scale (NIHSS) score. Functional outcome was evaluated at discharge using the modified Rankin scale (m-Rankin). Multivariate analyses were performed using logistic regression models. During the study period, 326 patients were diagnosed as AIS and were included in the analysis. Serum 25(OH) D levels reduced with increasing severity of stroke as defined by the NIHSS score. There was a negative correlation between levels of 25(OH) D and the NIHSS (r = ? 0.389, P = 0.000). In multivariate analyses, serum 25(OH) D level was an independent prognostic marker of discharge favorable functional outcome and survival [odds ratio 3.96 (2.85–7.87) and 3.36 (2.12–7.08), respectively, P = 0.000 for both, adjusted for NHISS, other predictors and vascular risk factors] in patients with AIS. Serum 25(OH) D levels are a predictor of both severity at admission and favorable functional outcome in patients with AIS. Additional research is needed on vitamin D supplementation to improve the outcome of post-stroke patients.     

Long Term Association between Serum 25-Hydroxyvitamin D and Mortality in a Cohort of 4379 Men

Objective

A number of observational studies have shown an inverse association between circulating 25-hydroxyvitamin D and total mortality, but a reverse J-shaped association has also been reported. In a large nested case-control study, serum-25-hydroxyvitamin D (s-25(OH)D) was positively associated with incident prostate cancer. Based on the same study population, the primary aim of the present study was to investigate the association between s-25(OH)D and total mortality.

Methods

Men participating in population based health screenings during 1981–1991 and enrolled in a nested case-control study were followed throughout 2007 with respect to all-cause and cause-specific mortality. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated using Cox proportional hazards regression.

Results

In men with prostate cancer (n = 2282), there was a significant inverse association between s-25(OH)D and total mortality after controlling for potential confounders (HR = 1.25 (95% CI 1.05–1.50), s-25(OH)D <50 nmol/l versus s-25(OH)D ≥50 nmol/l). The corresponding figure among controls (n = 2147) was HR = 1.15 (95% CI 0.88–1.50) and in the total study population HR = 1.19 (95% CI 1.03–1.38). For cause-specific deaths, we found no significant associations.

Conclusions

In this study population, s-25(OH)D was inversely associated with total mortality during more than two decades of follow-up, despite, as previous reported, high s-25(OH)D was associated with increased risk of prostate cancer.     

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

Background/Aims

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

Methods

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

Results

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

Conclusion

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

Low Serum 25-Hydroxyvitamin D Levels Are Associated with Dry Eye Syndrome

Background

Dry eye syndrome (DES) is a common tear film and ocular surface disease that results in discomfort, visual disturbance, and tear film instability with potential damage to the ocular surface. Systemic diseases associated with DES include diabetes mellitus, rheumatoid arthritis, depression, anxiety, thyroid disease, allergic diseases, irritable bowel syndrome, chronic pain syndrome, and hyperlipidemia. Interestingly, it has been found that most of these are associated with low levels of serum 25-hydroxyvitamin D (25(OH)D) or inadequate sunlight exposure.

Methods

In this cross-sectional data analysis, noninstitutionalized adults aged ≥19 years (N = 17,542) who participated in Korean National Health and Nutrition Examination Survey 2010–2012 were included. Information regarding duration of sunlight exposure was collected from the survey participants. Serum 25(OH)D and zinc levels were measured. The confounding variables were age, gender, sunlight exposure time, region of residence, obesity, serum 25(OH)D level, diabetes mellitus, rheumatoid arthritis, depression, thyroid disorder, atopic dermatitis, history of ocular surgery, regular exercise, and walking exercise.

Results

Mean serum 25(OH)D levels of subjects with and without DES were 16.90 ± 6.0 and 17.52 ± 6.07 (p<0.001). Inadequate sunlight exposure time (odds ratio [OR], 1.554; 95% confidence interval [CI], 1.307–1.848), urban residence (OR, 1.669; 95% CI, 1.456–1.913), indoor occupation (OR, 1.578; 95% CI, 1.389–1.814), and low serum 25(OH)D level (OR, 1.158; 95% CI, 1.026–1.308) were the risk factors for DES. After adjusting for age, sex, obesity, diabetes mellitus, rheumatoid arthritis, depression, thyroid disorder, atopic dermatitis, history of ocular surgery, regular exercise, and occupation, low serum 25(OH)D level (OR, 1.178; 95% CI, 1.010–1.372) and deficient sunlight exposure time (OR, 1.383; 95% CI, 1.094–1.749) were the risk factors for diagnosed DES.

Conclusion

Low serum 25(OH)D levels and inadequate sunlight exposure are associated with DES in Korean adults. These results suggest that sufficient sunlight exposure or vitamin D supplementation may be useful in DES treatment.     

Serum 25-Hydroxyvitamin D Deficiency in Chinese Patients with Vitiligo: A Case-Control Study

Background

Low vitamin D levels have been noted in patients with a variety of autoimmune diseases. A recent study showed that low vitamin D levels may be associated with vitiligo.

Objectives

To assess 25-hydroxyvitamin D (25(OH)D) status in Chinese patients with vitiligo in comparison of normal controls and explore possible affecting factors.

Methods

We performed a case-control study including 171 patients, 50 controls in 25(OH)D lowest months and 30 patients, 20 controls in 25(OH)D highest months. Demographic and clinical variables of patients were analyzed to determine the correlation with 25(OH) D levels.

Results

25(OH)D mean value of patients was highest in September and October, lowest in March. None of the patients and normal controls had ‘sufficient’ 25(OH)D (> = 75 nmol/L). No significant difference was found in either 25(OH)D mean values or insufficiency/deficiency ratio between patients and controls in 25(OH)D highest and lowest periods. Female patients were at a higher risk of 25(OH)D deficiency than male patients(P = 0.019). For non-segmental type, patients with 25(OH)D deficiency were more likely to have autoimmune thyroid disease than those with insufficiency (P = 0.016). Sex (P = 0.035), thyroid conditions (p = 0.034), testing month (p = 0.049) were independent factors affecting 25(OH)D level in multivariate analysis.

Conclusion

Chinese population lack 25(OH)D universally. 25(OH)D level shows no correlation with onset of vitiligo in Chinese. However deficient 25(OH)D level may be linked to autoimmune disorders in patients.     

Seasonal Genetic Influence on Serum 25-Hydroxyvitamin D Levels: A Twin Study

Background

Although environmental factors, mainly nutrition and UV-B radiation, have been considered major determinants of vitamin D status, they have only explained a modest proportion of the variation in serum 25-hydroxyvitamin D. We aimed to study the seasonal impact of genetic factors on serum 25-hydroxyvitamin D concentrations.

Methodology/Principal findings

204 same-sex twins, aged 39–85 years and living at northern latitude 60°, were recruited from the Swedish Twin Registry. Serum 25-hydroxyvitamin D was analysed by high-pressure liquid chromatography and mass spectrometry. Genetic modelling techniques estimated the relative contributions of genetic, shared and individual-specific environmental factors to the variation in serum vitamin D. The average serum 25-hydroxyvitamin D concentration was 84.8 nmol/l (95% CI 81.0–88.6) but the seasonal variation was substantial, with 24.2 nmol/l (95% CI 16.3–32.2) lower values during the winter as compared to the summer season. Half of the variability in 25-hydroxyvitamin D during the summer season was attributed to genetic factors. In contrast, the winter season variation was largely attributable to shared environmental influences (72%; 95% CI 48–86%), i.e., solar altitude. Individual-specific environmental influences were found to explain one fourth of the variation in serum 25-hydroxyvitamin D independent of season.

Conclusions/Significance

There exists a moderate genetic impact on serum vitamin D status during the summer season, probably through the skin synthesis of vitamin D. Further studies are warranted to identify the genes impacting on vitamin D status.     

Serum Levels of 25-Hydroxyvitamin D and Functional Outcome among Postmenopausal Women with Hip Fracture

Objective

The main objective of the current study was to assess the distribution and its prognostic value of serum 25-hydroxyvitamin D (25[OH] D) levels assessed at admission in Chinese postmenopausal women with hip fracture.

Methods

From January 1, 2012 to December 31, 2013, all postmenopausal women with first-ever hip fracture were recruited to participate in the study. Serum 25[OH] D levels were measured at admission. The functional evaluation at the time of discharge was performed by the Barthel Index (BI). The prognostic value of 25[OH] D to predict the functional outcome within discharge was analyzed by logistic regression analysis, after adjusting for the possible confounders.

Results

In our study, 261 patients were included and assessed. In the 76 patients with an unfavorable functional outcome, serum 25(OH) D levels were lower compared with those in patients with a favorable outcome [11.8(IQR, 9.9–16.1)ng/ml; 16.8(IQR, 13.6–21.4)ng/ml, respectively; P<0.0001]. In multivariate analysis, there was an increased risk of unfavorable outcome associated with serum 25(OH) D levels ≤ 20ng/ml (OR 5.24, 95%CI: 3.11–8.15; P<0.0001) after adjusting for possible confounders.

Conclusions

Our data support an association between serum 25[OH] D levels and prognosis in Chinese postmenopausal women with hip fracture.     

Serum 25-Hydroxyvitamin D and the Incidence of Acute Viral Respiratory Tract Infections in Healthy Adults

Background

Declining serum concentrations of 25-hydroxyvitamin D seen in the fall and winter as distance increases from the equator may be a factor in the seasonal increased prevalence of influenza and other viral infections. This study was done to determine if serum 25-hydroxyvitamin D concentrations correlated with the incidence of acute viral respiratory tract infections.

Methodology/Findings

In this prospective cohort study serial monthly concentrations of 25-hydroxyvitamin D were measured over the fall and winter 2009–2010 in 198 healthy adults, blinded to the nature of the substance being measured. The participants were evaluated for the development of any acute respiratory tract infections by investigators blinded to the 25-hydroxyvitamin D concentrations. The incidence of infection in participants with different concentrations of vitamin D was determined. One hundred ninety-five (98.5%) of the enrolled participants completed the study. Light skin pigmentation, lean body mass, and supplementation with vitamin D were found to correlate with higher concentrations of 25-hydroxyvitamin D. Concentrations of 38 ng/ml or more were associated with a significant (p<0.0001) two-fold reduction in the risk of developing acute respiratory tract infections and with a marked reduction in the percentages of days ill.

Conclusions/Significance

Maintenance of a 25-hydroxyvitamin D serum concentration of 38 ng/ml or higher should significantly reduce the incidence of acute viral respiratory tract infections and the burden of illness caused thereby, at least during the fall and winter in temperate zones. The findings of the present study provide direction for and call for future interventional studies examining the efficacy of vitamin D supplementation in reducing the incidence and severity of specific viral infections, including influenza, in the general population and in subpopulations with lower 25-hydroxyvitamin D concentrations, such as pregnant women, dark skinned individuals, and the obese.     

广泛性焦虑障碍血清25-羟维生素D、维生素B12与认知功能和临床疗效的关系

摘要 目的：探讨广泛性焦虑障碍（GAD）患者血清25-羟维生素D[25（OH）D]、维生素B12（VB12）与认知功能和临床疗效的关系。方法：选择2018年4月~2022年6月期间空军军医大学第一附属医院心理科门诊收治的186例GAD患者作为GAD组。另选取同期于我院体检健康的志愿者120例作为对照组。采用威斯康星卡片分类测验（WCST）评估并对比两组患者的认知功能,检测并对比两组患者的血清25（OH）D、VB12水平。采用Pearson相关性分析血清25（OH）D、VB12与认知功能的相关性。GAD组给予常规治疗,按照治疗效果分为有效组和无效组,对比有效组和无效组在治疗前后血清25（OH）D、VB12水平变化。结果：GAD组的血清25（OH）D、VB12水平低于对照组（P<0.05）。对照组完成总分类数、正确反应数、总反应数均多于GAD组,错误应答数、持续性错误数少于GAD组（P<0.05）。Pearson相关性分析结果显示,血清25（OH）D、VB12水平与错误应答数、持续性错误呈负相关;而与总分类数、正确反应数、总反应数呈正相关（P<0.05）。186例患者中,痊愈36例,疗效显著53例,有效62例,无效35例。按照治疗情况将患者分为有效组（n=151）和无效组（n=35）。两组治疗后血清25（OH）D、VB12水平均升高,且有效组高于对照组（P<0.05）。结论：GAD患者的25（OH）D、VB12水平下降,且与其认知功能下降有关,25（OH）D、VB12水平较低的GAD患者其治疗效果也相对更差,提示临床诊疗过程中应密切关注患者25（OH）D、VB12水平以制定相应的治疗措施。     

Serum 25-Hydroxyvitamin D Levels and Dry Eye Syndrome: Differential Effects of Vitamin D on Ocular Diseases

Purpose

To investigate associations between serum 25-hydroxyvitamin D levels and dry eye syndrome (DES), and to evaluate the differential effect of vitamin D on ocular diseases including age-related macular disease (AMD), diabetic retinopathy (DR), cataract, and DES.

Methods

A total of 16,396 participants aged >19 years were randomly selected from the Korean National Health and Nutrition Examination Survey. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. DES was defined by a history of clinical diagnosis of dry eyes by a physician. The association between vitamin D and DES was compared to the associations between vitamin D and AMD, DR, cataract, and DES from our previous studies.

Results

The odds of DES non-significantly decreased as the quintiles of serum 25-hydroxyvitamin D levels increased (quintile 5 versus 1, OR = 0.85, 95%CI: 0.55–1.30, P for trend = 0.076) after adjusting for potential confounders including age, sex, hypertension, diabetes, smoking status, and sunlight exposure times. The relative odds of DES (OR = 0.70, 95% CI: 0.30–1.64) and cataract (OR = 0.76, 95% CI: 0.59–0.99) were relatively high, while those of DR (OR = 0.37, 95% CI: 0.18–0.76) and late AMD (OR = 0.32, 95% CI: 0.12–0.81) were lower in men.

Conclusions

The present study does not support an association between serum 25-hydroxyvitamin D levels and DES. The preventive effect of serum 25-hydroxyvitamin D may be more effective for DR and late AMD than it is for cataract and DES.     

Association of Serum 25-Hydroxyvitamin D with Symptoms of Depression After 6 Months in Stroke Patients

Our aim was to determine whether there was a relationship between 25-hydroxyvitamin D (25[OH] D) and post-stroke depression (PSD). Two hundred and forty-four ischemic stroke patients admitted to the hospital within the first 24 h after stroke onset were consecutively recruited and followed up for 6 months. Clinical information was collected. Serum 25[OH] D levels were measured at baseline. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for depression at 6-month after stroke. At 6-month, 91 patients (37.3 %) showed depression and in 60 patients (24.6 %) this depression was classified as major. There was a significant difference in median serum 25[OH] D levels between PSD patients and no depression cases [8.3 (IQR, 6.8–9.5) vs. 15.6 (IQR, 13.2–20.3) ng/ml, respectively; P < 0.001]. Serum 25[OH] D levels ≤11.2 ng/ml were independently associated with PSD [odds ratio 10.32, 95 % confidence interval 4.97–28.63; P < 0.001], after adjusting for possible confounders. Serum 25[OH] D levels reduced at admission was found to be associated with PSD. Additional research is needed on vitamin D supplementation to improve the outcome of patients with PSD.     

25-Hydroxyvitamin D3 loading test in primary hyperparathyroidism, hypoparathyroidism and pseudohypoparathyroidism

Plasma 1,25-dihydroxyvitamin D (1,25-(OH)2D) level, which is considered to be an indicator of parathyroid function, is possibly modified by the level of vitamin D. In the present study, we have investigated parathyroid function in terms of enhancement of the plasma levels of 1,25-(OH)2D after oral administration of 100 micrograms of 25-hydroxyvitamin D3 (25OHD3) in 9 cases of primary hyperparathyroidism (1 degree HPT), 7 cases of hypoparathyroidism (HP), 2 cases of pseudohypoparathyroidism (PHP) and 6 normal subjects. The plasma levels of 25-hydroxyvitamin D (25OHD) increased and reached a peak at 6-12 hours after the administration of 25OHD3. The plasma levels of 1,25-(OH)2D slightly increased but remained within the normal range after 25OHD3 administration in 3 of the normal subjects whose basal levels were rather low, but the increase in plasma 1,25-(OH)2D in control subjects was not statistically significant. In cases of 1 degrees HPT, the plasma 1,25-(OH)2D level rose significantly in all cases (P less than 0.05), although the pattern of the increase was not uniform. These increases were remarkable in the patients whose basal levels were low. On the other hand, an increase in the level was rarely observed in any of the cases of HP and in one of the cases of PHP. In another case, normocalcemic PHP, the plasma 1,25-(OH)2D level rose.(ABSTRACT TRUNCATED AT 250 WORDS)     

Association of Low Serum 25-Hydroxyvitamin D Levels in Pregnancy with Glucosehomeostasis and Obstetric And Newborn Outcomes

ObjectiveTo evaluate the association of maternal serum 25-hydroxyvitamin D (25[OH]D) status with glucose homeostasis and obstetric and newborn outcomes in women screened for gestational diabetes mellitus (GDM).MethodsConsecutive women were screened for GDM at 24 to 28 weeks’ gestation during the months of maximal sunlight exposure in Spain (June through September). Serum 25(OH)D levels and parameters of glucose homeostasis were measured. Outcomes of the delivery and newborn were collected.ResultsTwo hundred sixty-six women were screened. Vitamin D deficiency (25[OH]D < 20 ng/mL) was observed in 157 women (59%). We observed an inverse correlation between 25(OH)D levels and hemoglobin A_1c, homeostasis model assessment of insulin resistance, serum insulin, and fasting and 1-hour oral glucose tolerance test glucose levels (P <.001). With a 25(OH)D concentration less than 20 ng/mL, the odds ratios were 3.31 for premature birth (95% confidence interval, 1.52-7.19; P <.002) and 3.93 for cesarean delivery (95% confidence interval, 2.00-7.73; P <.001). A 25(OH)D concentration of 20 ng/mL had 79% sensitivity and 51% specificity for cesarean delivery and 80% sensitivity and 45% specificity for premature birth. The cutoffs with the best combination of sensitivity and specificity were 16 ng/mL for cesarean delivery (62.9% sensitivity and 61.2% specificity) and 14 ng/mL for premature birth (66.7% sensitivity and 71.0% specificity).ConclusionsIn the population we sampled, vitamin D deficiency is very common during pregnancy. Lower 25(OH)D levels are associated with disorders of glucose homeostasis and adverse obstetric and newborn outcomes.(Endocr Pract. 2012;18:676-684)