Serum 25(OH)D Level and Parathyroid Hormone in Chinese Adult Population: A Cross-Sectional Study in Guiyang Urban Community from Southeast of China

Level of 25-hydroxyvitamin D and vitamin D receptor in diabetic foot ulcer and factor associated with diabetic foot ulcers

BACKGROUND

At present, there is no clinical study to elucidate the correlation between vitamin D deficiency and the incidence of diabetic foot osteomyelitis (DFO).This study aims to clarify levels of 25-hydroxyvitamin D [25(OH)VD] in peripheral blood and vitamin D receptor (VDR) expression in wound margin tissues (T-VDR) of patients with type 2 diabetes mellitus (T2DM) with diabetic foot ulcer (DFU) and DFO, and to determine its correlation with treatment outcomes of DFU and DFO, and and its value as a potential biomarker for the diagnosis of DFU and DFO.

METHODS

156 T2DM patients with DFU (DFU group), 100 T2DM patients without DFU (T2DM group), and 100 healthy controls (NC group). The DFU group patients were subdivided into DFO (n = 80) and NDFO groups (n = 76). The level of serum 25(OH)VD was measured via chemiluminescence immunoassay, and T-VDR expression level was determined by quantitative real-time PCR.

RESULTS

The levels of serum 25(OH)VD in the DFU group were significantly lower than the T2DM group [(10.3 (5.8, 18.7) vs 15.7 (8.6, 24.6) ng/mL, P = 0.002)]. Similarly, the levels of serum 25(OH)VD and T-VDR expression in the DFO group were statistically lower than the NDFO group [9.2 (5.2, 20.5) vs 12.8 (6.9, 22.1) ng/mL, P = 0.006)], [1.96 (0.61, 3.97) vs 3.11 (1.36, 5.11), P = 0.004)], respectively. Furthermore, the levels of serum 25(OH)VD and T-VDR expression in DFU patients were positively correlated with the ulcer healing rate of foot ulcer after 8 weeks of treatment ( P = 0.031, P = 0.016, respectively). Multivariate logistic regression analysis showed that low level of serum 25(OH)VD was an independent risk factor for DFU and DFO (OR_DFU = 2.42, OR_DFO = 3.05, P = 0.008, 0.001, respectively), and decreased T-VDR expression level was an independent risk factor for DFO (OR = 2.83, P = 0.004). Meanwhile, the ROC curve analysis indicated that the AUC of serum 25(OH)VD level for the diagnosis of DFU and DFO was 0.821 (95% CI, 0.754-0.886, P < 0.001) and 0.786 (95%CI, 0.643-0.867, P < 0.001), respectively. When establishing a diagnosis of DFO, the AUC of T-VDR expression level was 0.703 (95%CI: 0.618-0.853, P < 0.001).

CONCLUSIONS

The levels of serum 25(OH)VD and T-VDR expression in DFU and DFO decreased. Serum 25(OH)VD and T-VDR are potentially valuable biomarkers for diagnosis and prognosis of DFU and DFO. .

Changes in Metabolic Parameters in Patients with Diabetic Kidney Disease Depending on the Status of D3

BACKGROUND

Type 2 diabetes is a metabolic disease characterized by hyperglycemia as a result of insulin resistance and decreased insulin secretion. A relatively large number of patients with this type of diabetes have abdominal obesity, which also affects insulin resistance development. Chronic hyperglycemia can lead to damage and dysfunction of various organs, and a striking example is diabetic nephropathy. Diabetic nephropathy is a specific kind of kidney damage that occurs due to complications of diabetes and is accompanied by the formation of diffuse or nodular glomerulosclerosis, which can lead to terminal renal failure and requires immediate substitution through renal therapy or renal transplantation. Diabetic nephropathy is diagnosed with albuminuria and a decrease in the rate of glomerular filtration.

METHODS

This review was based on a literature search for the most important evidence of vitamin D as a possible method of prevention for obesity, type 2 diabetes, and diabetic nephropathy. Collected published articles were summarized according to their overall themes.

RESULTS

In this review, we considered vitamin D as a possible method of treatment for type 2 diabetes, as well as its complications, including diabetic nephropathy.

CONCLUSION

Studies show that vitamin D inhibits the renin-angiotensin-aldosterone system, resulting in improved renal function in diabetic nephropathy. Vitamin D also has antiinflammatory, antiproliferative, and anti-metastatic effects, which improve endothelial function.

A Retrospective Analysis of the Relationship Between 25-OH-Vitamin D and Diabetic Foot Ulcer

Background

The fat-soluble molecule vitamin D has attracted much attention since its pleiotropism was discovered. Its effectiveness can be attributed to the presence of vitamin D receptors in most of the body's tissues. Based on the classical role of vitamin D in regulating calcium and phosphorus metabolism and maintaining bone health, the role of vitamin D in immunity, type 2 diabetes mellitus (T2DM), tumor and cardiovascular diseases has been further discovered. Some experiments have shown that vitamin D can restore the production of antimicrobial peptides (AMP) in primary diabetic foot ulcer (DFU) cells, which can improve in vitro wound healing, indicating its potential therapeutic use in DFU therapy. In addition, vitamin D can also inhibit the secretion of T-helper type 1 (Th1) cytokines IFN-Y and IL-2 while stimulating the production of Th2 cytokines, thereby promoting wound healing.

Objective

To investigate the relationship between 25-OH-vitamin D level and DFU in diabetes mellitus (DM) patients, and to provide a theoretical basis for the early prevention and treatment of DFU.

Methods

The clinical data of 429 hospitalized patients with DM were retrospectively analyzed in this case-control study. The patients were divided into the DFU group (n = 242) and non-DFU group (n = 187). Fasting venous blood was drawn from all subjects to detect serum 25-OH-vitamin D levels and blood biochemical parameters, the difference of parameters between DFU group and non-DFU group were analyzed, and the risk factors of DFU were analyzed by logistic regression.

Results

The difference between the two groups in age, DM duration, gender, diastolic blood pressure, serum creatinine, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, albumin, white blood cell count, hemoglobin, hematocrit, 25-OH-vitamin D was statistically significant (p < 0.05). Multivariate logistic regression analysis showed that 25-OH-vitamin D is an independent protective factor for DFU [OR 95%, CI 0.984 (0.969, 0.998), p < 0.05]. 25-OH-vitamin D nutrition status distribution was different between non-DFU group and DFU group (P < 0.05). Vitamin D deficiency (< 50 nmol/L) accounted for 86.78% of all DFU patients, which was only 74.33% in non-DFU patients. The 25-OH-vitamin D levels of DFU patients from Wagner Grades 1 to 5 showed a downward trend (p < 0.01).

Conclusion

In conclusion, our study confirms that 25-OH-vitamin D is closely correlated with DFU and that 25-OH-vitamin D is an independent protective factor for DFU. Therefore, vitamin D screening or supplementation might be beneficial to prevent DFU and improve the prognosis of DM patients.

The Prevalence of Vitamin D and Calcium Supplement use and Association with Serum 25-Hydroxy-vitamin D (25(OH)D) and Demographic and Socioeconomic Variables in Iranian Elderly

Aims:

The objective of this study was to determine the prevalence of vitamin D and calcium supplement use, and association with serum 25-hydroxy-vitamin D(25(OH)D) and demographic and socioeconomic variables in Iranian elderly.

Settings and Design:

This cross-sectional study was conducted in health centers of Tehran, capital of Iran.

Methods:

A total of 600 men and women were recruited using a two-stage cluster sampling method from 60 health centers. Participant's inclusion criteria included enrolling older adults over 60 years old who able to answer questions. We used valid and reliable questionnaires to record dietary intake of vitamin D and calcium. Any dietary supplements which included vitamin D/calcium were recorded. 25(OH)D level was measured. Participants were categorized as supplement users if they had taken supplements during last month.

Results:

The mean age of participants was 67.16 ± 6.07 years. Vitamin D supplements were used more often by females (OR = 11.89, 95% confidence interval (CI): 4.82–29.34), high educated subjects (OR = 3.49, 95% CI: 1.45–8.44), participants who did more physical activities (OR = 2.75, 95% CI: 1.52–5.00), and subjects who took antiosteoporosis medications (OR = 6.90, 95% CI: 2.84‑16.78). Calcium supplements were used more often by females (OR = 13.05, 95% CI: 5.19–32.81), more physical activities participants (OR = 2.17, 95% CI: 1.20–3.92), and antiosteoporosis users (OR = 8.31, 95% CI: 3.43–20.14). Significant positive associations were seen between 25(OH) D levels and osteoporosis (P = 0.020), vitamin D supplement use (P < 0.0001), and sun exposure (P = 0.093).

Conclusion:

In this population of Tehranian adults, the prevalence of vitamin D and calcium supplement use may be attributed to educational level and underlying disease. Vitamin D supplementation, osteoporosis, and sun exposure were the strong predictors of vitamin D status.

Sleep duration is associated with vitamin D deficiency in older women living in Macao, China: A pilot cross-sectional study

Chinese women are known to have both a high prevalence of metabolic syndrome (MetS) and vitamin D deficiency (serum 25-hydroxyvitamin D (25OHD) <50 nmol/l). Associations between sleep duration and circulating 25OHD have recently been reported but, to our knowledge, these associations have not been studied in older Chinese populations. We thus investigated whether sleep duration was associated with vitamin D status in a population from Macao, China, and whether sleep duration modified the association between MetS and vitamin D deficiency. In 207 older (>55 years) Macanese, anthropometry, blood samples and validated questionnaires, including sleep duration and cardiovascular risk factors, were simultaneously collected. On multivariable categorical analyses, those women, not men, who had short sleep duration (≤6 hours (h)) were at a 2-fold risk for vitamin D deficiency (both <50 nmol/L and <37 nmol/L; OR = 1.94, 95%CI 1.29–2.92; OR = 2.05, 95%CI 1.06–3.98, respectively) and those who had longer sleep duration (>8 h) were 3-fold more likely to have vitamin D deficiency (OR = 3.07, 95%CI 1.47–6.39; OR = 2.75, 95%CI 1.08–7.00, respectively) compared to those with normal sleep duration (6–8 h). Both women and men with MetS were 2-fold more likely to have vitamin D deficiency (women: OR = 2.04, 95%CI 1.31–3.17; OR = 2.15, 95%CI 1.11–4.17, respectively; men: OR = 2.01, 95%CI 1.23–3.28; OR = 2.04, 95%CI 1.00–4.29, respectively). Moreover, women with both short sleep duration and MetS had an increased risk of vitamin D deficiency (OR = 3.26, 95%CI 1.10–9.64). These associations were not found in those with longer sleep. Men with longer sleep and MetS had a 5-fold risk of vitamin D deficiency (OR = 5.22; 95%CI 2.70–10.12). This association was non-significant for men with shorter sleep. We conclude that both short and long sleep duration were associated with vitamin D deficiency in older Chinese women. Further research is needed in larger cohorts or with intervention studies to further examine the associations between reduced sleep, metabolic syndrome and vitamin D deficiency.

Is There Any Relationship between Plasma 25-Hydroxyvitamin D₃, Adipokine Profiles and Excessive Body Weight in Type 2 Diabetic Patients?

A growing interest in the role of vitamin D in metabolic diseases led us to study the relationships between 25-hydroxyvitamin D₃ (25(OH)D₃) and the profiles of selected adipokines in type 2 diabetic (T2DM) patients. The study comprised 92 type 2 diabetics divided into quartiles regarding 25(OH)D₃ concentration. Each group was divided into male and female subgroups. All the studied patients had their anthropometric and biochemical parameters determined. Plasma 25-hydroxyvitamin D₃ concentration was determined by HPLC, while the selected adipokines (leptin, adiponectin, resistin and visfatin) by ELISA methods. The ratio of leptin to adiponectin (L/A) was calculated for all the patients. In 85.3% of diabetics a full (<20 ng/mL) or moderate (20-30 ng/mL) vitamin D deficit was found. Irrespective of sex, plasma leptin concentration decreased across increasing quartiles of 25(OH)D₃ level. In women, 25(OH)D₃ was negatively correlated with BMI, leptin level as well as L/A ratio, and positively with adiponectin concentration. In men, 25(OH)D₃ was positively correlated with HDL and negatively with systolic blood pressure (SBP), leptin level and L/A ratio. Considering all the patients, there ocurred a significant negative correlation between 25(OH)D₃ and SBP, BMI, WHR, TG, leptin and L/A ratio and positive ones between 25(OH)D₃ and both adiponectin and HDL. The results of the study support the existence of the relationship among vitamin D, obesity and leptin in type 2 diabetic patients.

Efficacy of high dose Vitamin D supplementation in improving serum 25(OH)D among migrant and non migrant population: a retrospective study

BACKGROUND

Higher dose of vitamin D supplementation 50000 IU is required for those whose serum 25(OH)D levels are 50 nmol/L and below. The increment in serum 25(OH)D though not significantly affected by race, sex or age it is negatively correlated to the baseline 25(OH)D concentration. This study investigated whether the mean increase in serum 25(OH)D will be higher among participants with lower baseline 25(OH)D levels and whether the duration of supplementation has an influence on the serum 25(OH)D achieved.

METHODS

A clinical audit of patients' medical records from a community health centre in Melbourne for the period 01.01.2010 to 31-12.2012 was undertaken. Paired sample t test was used to determine difference in pre and post dose serum 25(OH)D. Simple and multiple linear regressions were used to examine the association between the difference in pre and post dose serum 25(OH)D and duration of supplementation and baseline serum 25(OH)D, adjusting for socio-demographic factors.

RESULTS

A total of 205 patients were included in the study. Mean difference in serum 25(OH)D was highest 52.8 nmol/L (95 % CI: 46.63-58.92) among those whose serum 25(OH)D was below 25 nmol/L at baseline. Baseline 25(OH)D alone accounted for 13.7 % of variance in the effect size (F(2, 202) = 16.0. p < 0.001), with the effect size significantly higher among participants with a baseline 25(OH)D level of 25-49 nmol/L (β = 11.93, 95 % CI: 0.48, 23.40, p < 0.05). Mean serum 25(OH)D difference was highest, 47.53 nmol/L (95 % CI: 40.95-54.11) when measured within 3 months of supplementation. Duration of supplementation explained 2.9 % of the variance in the effect size (F (1, 203) = 6.11, p < 0.05) and there was an inverse relationship between the length of supplementation and mean pre and post supplementation serum 25(OH)D difference (β = -1.45, 95 % CI: -2.62, -0.29, p = 0.014).

CONCLUSION

Following 50000 IU vitamin D3 for 12 months mean serum 25(OH)D increase was highest among those whose baseline serum 25(OH)D was lower. Migrants especially dark-skinned are at a high risk for vitamin D deficiency in Australia. High dose vitamin D3 50000 IU (cholecalciferol) is effective in achieving sufficient serum 25(OH)D among these populations who tend to have lower baseline serum 25(OH)D.

A Clinical Analysis of Vitamin D Status in Patients Before Spinal Surgery

The goal of this paper was to study preoperative concentrations of vitamin D in patients undergoing spinal surgery and analyze relevant risk factors associated with vitamin D deficiency. Vitamin D plays an important role in maintaining normal functions of skeletal muscles, and vitamin D insufficiency or deficiency may affect outcomes of spinal surgery patients. A retrospective analysis was conducted on 503 patients undergoing spinal surgery in the First Affiliated Hospital with Nanjing Medical University from September 2012 to October 2013. Preoperative concentrations of serum 25-hydroxyvitamin D [25(OH)D] were measured. Normal vitamin D was defined as a serum 25(OH)D level ≥ 32 ng/mL, vitamin D insufficiency as ≥20 and &lt;32 ng/mL, and vitamin D deficiency as &lt;20 ng/mL. Relevant risk factors associated with vitamin D insufficiency and deficiency were analyzed. In 503 spinal surgery patients, rate of vitamin D deficiency and insufficiency was 71.4% and 23.9%. Rate of vitamin D deficiency in female patients was significantly higher than that in male (P &lt; 0.001). Rate of vitamin D deficiency in patients with high body mass index (P = 0.009) or patients with smoking habit (P &lt; 0.001) was much higher than other patients. Multivariate analysis demonstrated that female (P &lt; 0.001), smoking (P = 0.005), and winter (P = 0.001) were potential risk factors for vitamin D deficiency. Screening preoperative vitamin D status and relevant treatment should be reinforced in spine surgery patients.

Vitamin D and parathyroid hormone status in a representative population living in Macau, China

Associations between documented sun-exposure, exercise patterns and fish and supplement intake and 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) were investigated in a random household survey of Macau residents (aged 18-93). Blood samples (566) taken in summer were analyzed for 25OHD and PTH. In this Chinese population, 55% were deficient (25OHD <50nmol/L: median (interquartile range)=47.7 (24.2) nmol/L). Vitamin D deficiency was greatest in those aged <50 years: median (interquartile range)=43.3 (18.2) nmol/L, females: median (interquartile range)=45.5 (19.4) nmol/L and those with higher educational qualifications: median (interquartile range)=43.1 (18.7) nmol/L. In the total Macau population, statistically significant (p<0.01) modifiable associations with lower 25OHD levels were sunlight exposure (β=0.06), physical activity (PA) (measured as hours(hrs)/day: β=0.08), sitting (measured as hrs/day β=-0.20), intake of fish (β=0.08) and calcium (Ca) supplement intake (β=0.06) [linear regression analysis adjusting for demographic risk factors]. On similar analysis, and after adjustment for 25OHD, the only significant modifiable associations in the total population with PTH were sitting (β=-0.17), Body Mass Index (β=0.07) and Ca supplement intake (β=-0.06). In this Macau population less documented sun exposure, fish and Ca supplement intake and exercise were associated with lower 25OHD levels, especially in the younger population, along with the interesting finding that more sitting was associated with both lower 25OHD and high PTH blood levels. In conclusion, unlike findings from Caucasian populations, younger participants were significantly more vitamin D deficient, in particular highly educated single females. This may indicate the desire of young females to be pale and avoid the sun. There are also big differences in lifestyle between the older generation and the younger, in particular with respect to sun exposure and PA. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

Serum 25-hydroxyvitamin D levels are associated with carotid atherosclerosis in normotensive and euglycemic Chinese postmenopausal women: the Shanghai Changfeng study

Background

The role of serum 25-hydroxyvitamin D (25 (OH) D) in atherogenesis is unclear. We investigated whether the 25 (OH) D is independently associated with the carotid intima–media thickness (CIMT) and carotid plaques in normotensive and euglycemic postmenopausal women.

Methods

A total of 671 normotensive and euglycemic postmenopausal women (mean age, 58.8 years) were enrolled from the Changfeng Study. A standard interview, anthropometrics measurements and laboratory analyses were performed for each participant. Bilateral CIMTs were measured using ultrasonography, and the presence of carotid plaques was assessed. The serum 25 (OH) D was measured using electrochemiluminescence immunoassay.

Results

Serum 25 (OH) D was 43.6 ± 18.2 nmol/L in the postmenopausal women. Compared with subjects with 25 (OH) D in the first, second and third quartiles, subjects with 25 (OH) D in the fourth quartile had decreased CIMT and prevalence of carotid plaque (0.684 ± 0.009 mm vs 0.719 ± 0.009 mm, 0.708 ± 0.009 mm and 0.709 ± 0.009 mm; 10.8% vs 19.0%, 14.8% and 16.8%, respectively). After adjusting for conventional CVD risk factors, PTH, liver and renal function, postmenopausal women with 25 (OH) D in the fourth quartile still had lower CIMT than those in the first, second and third quartiles (p = 0.039) and the subjects in the fourth quartile had a 0.421-fold decreased risk of carotid plaques relative to those in the lowest quartile (95% confidence interval 0.209 to 0.848).

Conclusions

These results suggest serum 25 (OH) D is independently and inversely associated with carotid atherosclerosis in postmenopausal women with normal blood pressure and normal glucose tolerance.