Association between vitamin D status and serum parathyroid hormone concentration and calcaneal stiffness in Japanese adolescents: sex differences in susceptibility to vitamin D deficiency

Seasonal Serum 25(OH) Vitamin D Level and Reproductive or Immune Markers in Reproductive-Aged Women with Infertility: A Cross-Sectional Observational Study in East Japan

Several studies have reported that vitamin D may modify human reproductive functions; however, the results are conflicting. We aimed to comprehensively evaluate serum vitamin D levels and examine the relationship between serum vitamin D levels and ovarian reserve markers, and immune markers of implantation, in reproductive-aged Japanese women with infertility.in reproductive-aged women with infertility. This cross-sectional, single-center study included reproductive-aged women who underwent preconception screening for fertility. Serum vitamin D levels and reproductive and immune markers were measured. Standard and advanced statistical techniques were used. We observed a statistically significant difference in the seasonal and monthly 25(OH) vitamin D levels; the 25(OH) vitamin D level during winter was the lowest among all seasons. However, there was no linear correlation between 25(OH) vitamin D levels and ovarian reserve markers, such as follicle-stimulating hormone and anti-Müllerian hormone, or the Th1/Th2 cell ratio, which is used as an implantation-related immunological marker. In this large-scale study, we evaluated the serum 25(OH) vitamin D concentration in reproductive-aged women with infertility in Japan; however, there was no association between reproductive function and vitamin D levels.

Estimation of the vitamin D (VD) status of pregnant Japanese women based on food intake and VD synthesis by solar UV-B radiation using a questionnaire and UV-B observations

Although vitamin D (VD; serum 25 hydroxyvitamin D) deficiency (< 20 ng/mL) is widespread among Japanese women, the VD status among pregnant women is unknown. This study aimed to determine the VD status of pregnant Japanese women during different meteorological seasons and to determine the factors controlling VD status. A total of 309 pregnant Japanese women were recruited at 28 weeks of gestation at the gynecology department of a university hospital in Tokyo between August 2018 and October 2019. Blood samples were collected to measure serum 25(OH)D levels. Two questionnaires were completed: a brief self-administered dietary history questionnaire (BDHQ) and an outdoor exposure history questionnaire to determine skin sunlight exposure and the use of sunscreen. Among the recruited subjects, 268 were included in the statistical analysis. The average VD intake from food was 9.0 μg/day, the average VD synthesis from UV-B was 15.2 μg/day, and the average sum of VD intake and nominal VD synthesis was 24.1 μg/day; this exceeded the recommended 2011 Dietary Reference Intake for the USA and Canada (15.0 μg/day). However, the average serum 25(OH)D level (11.4 ng/mL) was very low, indicating widespread VD deficiency. Serum 25(OH)D and VD synthesis by solar UV-B were significantly correlated only during the high UV-B season. The 25(OH)D level was weakly correlated with the VD intake from food in all seasons. We obtained a statistically significant correlation between serum 25(OH)D level and VD intake from food using the BDHQ. We also obtained a statistically significant correlation between the serum 25(OH)D level and VD synthesis from solar UV-B exposure, especially during the high UV-B season. Our logistic regression analysis model predicted VD deficiency in 88.0% of subjects. Our method might be possible to be used to predict the VD status of pregnant Japanese women, although another validation cohort is needed to verify the ability of the estimation equation.

Vitamin D deficiency in children with severe disabilities under limited ultraviolet exposure

INTRODUCTION

Nutritional prevention of osteoporosis management is an important issue for children with severe disabilities. Due to the coronavirus disease 2019 (COVID-19) pandemic that started in 2020, children admitted to institutions had fewer opportunities for ultraviolet (UV) exposure owing to restrictions on attending school and going out. Hence, the vitamin D (VD) status of these children has been a cause of concern. This study aimed to assess the correlation between VD intake and VD status among children with severe disabilities who had limited UV exposure.

MATERIALS AND METHODS

This research included patients admitted to Iwate Prefectural Rehabilitation and Nursery Center for Disabled Children. Serum 25-hydroxyvitamin D [25(OH)D] levels were assessed during school/outing restriction periods and after restriction removal and the introduction of sunbathing periods. The trends in 25(OH)D levels and oral VD intake before the two measurements were analyzed.

RESULTS

Although 17 of 32 patients had VD intake above the recommended level of Dietary Reference Intakes for Japanese during the first measurement, 31 patients had VD deficiency. The 25(OH)D levels of 13 patients without UV exposure before the first evaluation and those with UV exposure before the second evaluation were 2.03 times higher, despite of constant VD intakes. In contrast, there were no remarkable changes in both VD intakes and 25(OH)D levels in five patients without UV exposure before both assessments.

CONCLUSION

Japanese children with severe disabilities who consume the recommended oral VD intake but who have limited UV exposure can still present VD deficiency.

Factors Associated with Low Vitamin D Status among Older Adults in Kuwait

Low vitamin D levels among older people represent a significant health problem worldwide. This study aimed to examine the factors associated with vitamin D deficiency in older people (aged ≥ 65) in the Kuwaiti population. A cross-sectional study was conducted in seven primary healthcare centers across Kuwait (November 2020 to June 2021). The participants (n = 237) had their serum vitamin D (25(OH)D) concentrations (analyzed using LC-MS) classified as sufficiency 75 nmol/L (30 ng/mL) or deficiency < 75 nmol/L (below 30 ng/mL). The data were collected using self-administered questionnaires and face-to-face interviews with participants in geriatric clinics. Binomial logistic regression analysis was applied to assess factors associated with vitamin D deficiency. Vitamin D deficiency was found to be present in two thirds of the participants (n = 150, 63%), with a higher prevalence of deficiency in participants who did not receive vitamin D supplements, compared to those who did (84% vs. 16%, p = 0.001). The results from the binary logistic regression showed that a low duration of sun exposure (OR = 0.24, 95% C.I. [0.08−0.7], p = 0.011), dark skin pigmentation (OR = 4.46, 95% [1.35−20.49], p = 0.026), and lower caloric intake (OR = 0.9, 95% C.I. [0.85−0.96], p = 0.001) were risk factors for vitamin D deficiency. Furthermore, a significant inverse relationship was found between vitamin D levels and parathyroid hormone (PTH) levels (OR = 1.16, 95% C.I. [1.04−1.31], p = 0.016). These findings support the recommendation that vitamin D supplementation and adequate sunlight exposure are necessary for raising low vitamin D levels in older people in Kuwait.

Development of a predictive model for vitamin D deficiency based on the vitamin D status in young Japanese women: A study protocol

Background

Vitamin D deficiency (VDD) is associated with an increased risk for lifestyle-related diseases. In Japan, VDD is quite prevalent in all age groups, with its high risk in young women. Furthermore, its association during pregnancy with gestational hypertension and low birth weight has also been reported. VDD can be diagnosed by serum 25-hydroxyvitamin D [25(OH)D] levels, which, however, is not suited for screening. Therefore, we will create a predictive model for serum 25(OH)D concentration and prevalence of VDD based on such data as region, sun exposure habit, and vitamin D intake in young women.

Methods

From 2020 to 2022, we conduct a cross-sectional study of 600 young women in four regions of Japan, identify the indices associated with serum 25(OH)D concentrations such as sun exposure habits, habitual vitamin D intake, ultraviolet-B irradiation, seasons (summer and winter) and latitude, and construct prediction models for serum 25(OH)D concentrations and VDD risk. This study has been registered with UMIN-CTR (ID: UMIN000041527).

Results

One hundred and fifteen subjects have been collected from 6 institutions in winter as of May 2021. When data from more than 200 subjects have become available, we will conduct the interim analysis, summarize the data by region and facility, review the inclusion criteria for analysis, and check for missing values and outliers. Prediction models for serum 25(OH)D concentration and VDD will be determined in the final analysis when all cases have been collected.

Conclusions

A screening tool for VDD risk to be developed in our study based on the predictive model would help the public and medical professionals prevent lifestyle-related diseases through improving VDD. Additionally, the results may serve as the scientific basis for determining the appropriate vitamin D intake and sun exposure standards.

Low serum 25-hydroxyvitamin D level is associated with obesity and atherogenesis in adolescent boys

PURPOSE

We investigated the relationship of 25-hydroxyvitamin D (25[OH]D) level with obesity and atherosclerosis in Japanese adolescents.

METHODS

We examined 492 children (247 boys and 245 girls) aged 12-13 years. The serum 25(OH)D level was compared among underweight, healthy weight, and overweight children. Spearman correlation coefficient analysis was performed to examine the relationships between the 25(OH)D level and body mass index (BMI), plasma lipids, and blood pressure and to compare the latter between the normal (≥20 ng/mL) and low (<20 ng/mL) 25(OH)D groups. Further, we performed a multiple regression analysis to assess the effect on the 25(OH)D level.

RESULTS

The serum 25(OH)D level was significantly lower in overweight (20.5±2.7 ng/mL) than in healthy-weight boys (22.4±3.3 ng/mL) (P=0.004). Spearman correlation coefficients comparing the relationship of the 25(OH)D level with BMI, high-density lipoprotein cholesterol (HDL-C), and atherogenic index indicated significance in boys (ρ=-0.238 [P<0.0001], ρ=0.197 [P=0.002], and ρ=-0.146 [P=0.022], respectively). In boys, the multiple regression analysis results showed that BMI had negative and HDL-C had positive effects on the 25(OH)D level. The first was higher and the latter was lower in boys with low 25(OH)D level than in those with normal levels, respectively (P<0.05). No significant correlations were detected in girls.

CONCLUSION

Low serum 25(OH)D level was associated with obesity and increased atherogenic risk in adolescent boys only. This sex difference was probably mediated by body composition, sun exposure, estrogen, and adiponectin, which are characteristics of puberty.

VITAMIN D STATUS IN A HEALTHY TUNISIAN POPULATION

Background

Vitamin D deficiency is one of the most common medical conditions worldwide. In Tunisia, several studies evaluated Vitamin D status, but this was concerning specific populations (pregnant women, obese or diabetic patients and children with asthma). The only study that evaluated Vitamin D status in a healthy Tunisian population was conducted by Meddeb and associeties in 2002. The update of data available, based on the currently recommended limits, is necessary. This study aimed to estimate the prevalence of hypovitaminosis D in a healthy Tunisian population, and correlate the values with potential risk factors.

Methods

It was conducted on 209 Tunisian healthy subjects. Data collected included clinical characteristics and dietary intakes. We measured 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH), glycemia, creatinine, calcium, phosphorus, and alkaline phosphatase concentrations. Hypovitaminosis D was retained for 25(OH)D concentrations <75 nmol/L. Vitamin D deficiency was defined by 25(OH)D concentrations <25 nmol/L.

Results

The prevalence of hypovitaminosis D and vitamin D deficiency were respectively 92.3% and 47.6%. The main factors that were significantly associated with low vitamin D levels in our multivariate analysis were veiling, living in rural areas and sunscreen use. However, sex, age, socioeconomic level, phototype, solar exposure score, smoking and bone mass index, were not statistically associated with hypovitaminosis D. The study of relationship between vitamin D status and serum PTH levels showed a significative and negative correlation (P < 0.005).

Conclusions

Given the high prevalence of vitamin D, an adapted health policy is essential. A widespread vitamin D supplementation and food fortification seems to be necessary in Tunisia.

PTHR1 Genetic Polymorphisms Are Associated with Osteoporosis among Postmenopausal Arab Women

The parathyroid hormone 1 receptor (PTHR1) plays a crucial role in calcium homeostasis and bone metabolism. However, its genetic role in regulating bone turnover markers (BTMs) in postmenopausal osteoporosis (PMO) remains unclear. Herein, we explored parathyroid hormone (PTH) and PTHR gene variant susceptibility to osteoporosis and their association with various circulating BTM and inflammatory markers in postmenopausal women of Arab ethnicity. In total, 600 postmenopausal Arab women (300-PMO and 300-control) were genotyped for selected SNPs in PTH (rs1459015, rs307253, rs6054, rs307247, rs10500783 and rs10500784), PTHR1 (rs6442037, rs1138518, and rs724449 SNPs) and PTHR2 (rs9288393, rs10497900, and rs897083). Anthropometrics, BTMs, and inflammatory markers were measured. Bone mineral density (BMD) was measured at the lumbar spine L1–L4 and the femoral neck using dual-energy X-ray absorptiometry (DXA). PTHR1 rs1138518 genotype C/T was found to be a significant risk factor for PMO (OR = 1.49, 95% CI 1.0-2.1, P = 0.03). The genotypes C/T and T/T of PTHR1 rs1138518 were associated with 25-hydroxy-vitamin D (25(OH)D) regulation. In the PMO group, carriers of the C/T genotype had significantly lower 25(OH)D levels than carriers of the same genotypes in the control group (59.9 (36.7-92.4) nmol/l and 66.4 (43.5-87.8) nmol/l, respectively; P = 0.048]. Our study concludes that the PTHR1 rs1138518 genotype could be a potential risk factor for osteoporosis and 25(OH)D regulation in Arab women with PMO.

Incidence rate of vitamin D deficiency and FGF23 levels in 12- to 13-year-old adolescents in Japan

INTRODUCTION

The incidence rate of vitamin D deficiency is increasing throughout the world. We measured the incidence rate of vitamin D deficiency and fibroblast growth factor 23 (FGF23) levels in 12- to 13-year-old adolescents in Japan.

MATERIALS AND METHODS

A total of 492 adolescents (247 boys and 245 girls) from Japanese community enrolled in this study. 25 hydroxyvitamin D (25(OH)D) was measured with radioimmunoassay. In the subjects with low 25(OH)D levels (≦ 20 ng/ml), intact parathyroid hormone (iPTH), calcium (Ca), phosphorus (P), albumin (Alb), alkaline phosphatase (ALP) and FGF23 were measured.

RESULTS

25(OH)D levels were significantly lower in girls (20.9 ± 3.1 ng/ml) than in boys (22.2 ± 3.3 ng/ml) (p < 0.0001). Fifty-five boys (22.3%) and 83 (33.9%) girls showed vitamin D deficiency (< 20 ng/ml). One-hundred eighty-six (75.3%) boys and 162 (66.1%) girls showed vitamin D insufficiency (≧ 20 ng/ml, < 30 ng/ml). In the subjects whose 25(OH)D levels were ≦ 20 ng/ml, the levels of iPTH, Ca, P, Alb, ALP and FGF23 were 22.3 ± 9.0 pg/ml, 9.5 ± 0.4 mg/dl, 4.7 ± 0.6 mg/dl, 4.6 ± 0.3 g/dl, 920.8 ± 339.3 U/l and 42.6 ± 26.0 pg/ml, respectively. There was a significant negative association between serum 25(OH)D levels and iPTH [r =  - 0.290 (p < 0.0001)]. There was no significant association between serum 25(OH)D levels and FGF23.

CONCLUSION

We show that 28% of Japanese 12- to 13-year-old early adolescents suffer from vitamin D deficiency. Findings from this study indicate that vitamin D deficiency requires close oversight in public health during adolescence to ensure proper bone health.

A high-fat diet in the presence of vitamin D deficiency status is associated with a negative influence on calcaneal quantitative ultrasound parameters in young adults: a cross-sectional study

Vitamin D deficiency and a high-fat diet are considered health problems worldwide. The aims of this study were to examine the prevalence of vitamin D deficiency/insufficiency in young adults, factors related to the vitamin D status, and the influence of vitamin D deficiency and/or a high-fat diet on bone parameters. Here, we investigated the hypothesis that a high-fat diet in the presence of a vitamin D-deficient status would have a more negative influence on bone parameters than a normal-fat diet with such a status. In the present study, we targeted young Japanese adults aged 21-23 (n = 175). We conducted a diet survey based on 3-day food records, biochemical examination of serum, and quantitative ultrasound measurements at the calcaneus. As a result, the rates of vitamin D deficiency {serum 25-hydroxyvitamin D₃ [25(OH)D] concentration less than 20 ng/mL} and insufficiency [serum 25(OH)D concentration less than 30 ng/mL but not less than 20 ng/mL] were 60.6 and 30.9%, respectively. A positive correlation was observed between the serum 25(OH)D level and serum bone-specific alkaline phosphatase level, which is a serum marker of bone formation (r = 0.253, P< .01) or the speed of sound (SOS) as an index of bone density (r = 0.259, P< .01). A negative correlation was observed between the ratio of fat intake to total energy intake (%E) and serum 25(OH)D levels (r = -0.206, P< .01). Furthermore, we revealed that a high-fat diet in the presence of a vitamin D deficient status reduced the SOS parameter compared with a normal-fat diet with a vitamin D-deficient status (P< .05).

Vitamin D in the Dietary Reference Intakes for Japanese (DRIs) 2020

Dietary Reference Intakes for Japanese (DRIs) are revised every five years. In DRIs 2020, major revision has been made on vitamin D (VD). In DRIs, five indices are defined for nutrients; estimated average requirement (EAR), recommended dietary allowance (RDA) and adequate intake (AI) for the prevention of deficiency/insufficiency, tolerable upper intake level (UL) for avoiding excess intake, and tentative dietary goal for preventing life-style related diseases (DG) for the primary prevention of life-style related diseases. For VD, AI has been determined. VD deficiency causes rickets and osteomalacia. VD insufficiency, milder than deficiency, is a risk for various diseases including osteoporotic fracture. Previously, the basis of AI for VD was the prevention of rickets and osteomalacia, but was changed to the median intake of healthy subjects in DRIs 2005. Recent studies have shown, however, that VD deficiency/insufficiency is quite prevalent, and the above basis is considered inadequate. Then in DRIs 2020, AI was defined as the amount necessary for fracture prevention (15 μg/d) minus that possibly produced in Sapporo during winter in the skin by ultraviolet (5 μg/d). UL and AI for infants were revised in DRIs 2015. For the future DRIs, more clinical and epidemiological studies are urgently needed.

Vitamin D deficiency as a risk factor for endometriosis in Iranian women

PURPOSE

Vitamin D (Vit D), as an immunomodulator, has been hypothesized to play a critical role in the pathogenesis of endometriosis. Thus, in this study, we evaluated whether there is an association between 25-hydroxyvitamin D [25(OH)D] and susceptibility to endometriosis in Iranian women.

METHODS

Women at reproductive age, including 56 healthy women and 54 patients with endometriosis, were enrolled in the study. Serum levels of 25(OH)D, calcium, parathyroid hormone (PTH), and peritoneal fluid (PF) levels of 25(OH)D were assessed.

RESULTS

The serum and PF levels of 25(OH)D in the patients with endometriosis were significantly lower than the control group (P = 0.001 and P = 0.03, respectively). Subjects with serum levels of 25(OH)D lower than 20 ng/mL had a 2.7 times higher risk of endometriosis than people with 25(OH)D serum levels higher than 20 ng/mL (non-deficient) (OR = 2.7, 95 % confidence interval: 1.24-5.80, P = 0.01). The serum levels of calcium and PTH were significantly lower and higher in patients with endometriosis compared with controls, respectively (P < 0.001, P = 0.02, respectively). Also, the serum levels of 25(OH)D were lower in stages I-II endometriosis than stage III-IV; however, no significant difference was observed.

CONCLUSION

Our findings showed that people with Vit D deficiency are at higher risk of endometriosis.

Insufficiency of B vitamins with its possible clinical implications

Vitamin deficiency causes classical deficiency diseases such as beriberi and rickets. Vitamin insufficiency, which is milder than deficiency, is a risk for various chronic diseases, but its significance has not been recognized in Japan. Vitamin D insufficiency is quite common in Japan, and a serious risk for osteoporotic fracture through its unbeneficial effect on bone and muscle. Insufficiency of B vitamins has been little studied. However, hyperhomocysteinemia caused by the insufficiency of vitamin B12 or folate is a risk for cardiovascular disease, osteoporotic fracture, and cognitive impairment. Additionally, we have recently reported that vitamin B1 insufficiency is a risk for heart failure in the elderly. The effect of improvement of nutritional status including vitamins is less marked compared to drug treatment, but it costs far less, and is suited for the primary prevention of diseases. Randomized controlled trial is considered the study with the most robust evidence in the evaluation of drug treatment, but more emphasis should be put on the well-designed cohort studies in evaluating the role of nutrients. Vitamin insufficiency is quite prevalent, and vitamin requirement is much higher for its prevention than for the prevention of deficiency.

Vitamin D in the Foot and Ankle: A Review of the Literature

BACKGROUND

Vitamin D is an essential vitamin that targets several tissues and organs and plays an important role in calcium homeostasis. Vitamin D deficiency is common, particularly at higher latitudes, where there is reduced exposure to ultraviolet B radiation. We reviewed the role of vitamin D and its deficiency in foot and ankle pathology.

METHODS

The effects of vitamin D deficiency have been extensively studied, but only a small portion of the literature has focused on the foot and ankle. Most evidence regarding the foot and ankle consists of retrospective studies, which cannot determine whether vitamin D deficiency is, in fact, the cause of the pathologies being investigated.

RESULTS

The available evidence suggests that insufficient vitamin D levels may result in an increased incidence of foot and ankle fractures. The effects of vitamin D deficiency on fracture healing, bone marrow edema syndrome, osteochondral lesions of the talus, strength around the foot and ankle, tendon disorders, elective foot and ankle surgery, and other foot and ankle conditions are less clear.

CONCLUSIONS

Based on the available evidence, we cannot recommend routine testing or supplementation of vitamin D in patients with foot and ankle pathology. However, supplementation is cheap, safe, and may be of benefit in patients at high risk for deficiency. When vitamin D is supplemented, the evidence suggests that calcium should be co-supplemented. Further high-quality research is needed into the effect of vitamin D in the foot and ankle. Cost-benefit analyses of routine testing and supplementation of vitamin D for foot and ankle pathology are also required.

Effects of ultraviolet irradiation with a LED device on bone metabolism associated with vitamin D deficiency in senescence-accelerated mouse P6

Aims

This study investigated effects of narrow-range ultraviolet irradiation (UVR) by a new UV–LED device on vitamin D supply and changes of bone in senescence-accelerated mouse P6 (SAMP6) with vitamin D deficiency.

Main methods

We used female SAMP6 mice as a senile osteoporotic model. We set a total of 3 groups (n = 4 per group); D-UVR+ group (vitamin D deficient–dietary and UVR), D- (vitamin D deficient–dietary), and D+ groups (vitamin D contained–dietary). Mice in the D-UVR + group were UV–irradiated (305nm) with 1 kJ/m² twice a week for 12 weeks from 20 to 32 weeks of age. Serum 25(OH)D, 1,25(OH)₂D, and micro–computed tomography (CT) were assessed over time. Mechanical test, and histological assay were performed for femurs removed at 32 weeks of age.

Key findings

UVR increased both serum 25(OH)D and 1,25(OH)₂D levels at 4 and 8 weeks–UVR in the D-UVR+ group compared with that in the D- group (P < 0.05, respectively). Relative levels of trabecular bone mineral density in micro–CT were higher in the D-UVR+ group than in the D- group at 8 weeks–UVR (P = 0.048). The ultimate load was significantly higher in the D-UVR+ group than in the D- group (P = 0.036). In histological assay, fewer osteoclasts and less immature bone (/mature bone) could be observed in the D-UVR+ group than in the D- group, significantly.

Significance

UVR may have possibility to improve bone metabolism associated with vitamin D deficiency in SAMP6 mice.

Optimal vitamin D intake for preventing serum 25-hydroxyvitamin D insufficiency in young Japanese women

Populations of East Asian countries have been known to have low calcium intakes and low serum 25(OH)D concentrations, suggesting that Ca and vitamin D (VitD)-deficiencies are commonly observed. These nutritional imbalances may lead to low peak bone mass (PBM). The low PBM seen in Ca/VitD-deficient individuals may lead to osteoporosis, as well as an increased risk of fracture. A survey was conducted in young Japanese women (n = 296, 21.2 ± 2.3 years old) on their Ca/VitD intakes and serum 25(OH)D levels, which demonstrated a significant positive correlation between VitD intake and serum 25(OH)D levels (R ² = 0.020, P = 0.016), and the proportion with serum 25(OH)D over 20 ng/mL was significantly increased with VitD intake (P = 0.013). Serum 25(OH)D was negatively correlated to serum intact parathyroid hormone (R ² = 0.053, P < 0.001). On receiver operating characteristic curve analysis, the VitD intake threshold for maintaining 25(OH)D levels at 20 ng/mL or higher was 11.6 μg/day or greater. It was suggested that the recommended VitD intake allowance, defined in the Adequate Intakes as 5.5 μg/day, may not be sufficient to maintain serum 25(OH)D levels for bone health.

Eldecalcitol increases bone mass in patients with Turner syndrome who have insufficient bone mass acquisition after estrogen replacement therapy

Most patients with Turner syndrome (TS) exhibit amenorrhea due to premature ovarian failure. Therefore, estrogen replacement therapy (ERT) is required; however, even after undergoing ERT, it is not rare for bone mass acquisition to be insufficient. This study was conducted in two stages, involving a cross-sectional and a prospective interventional study. We recruited 52 TS patients undergoing ERT due to amenorrhea (categorized into low (LB group; n = 23), and normal (NB group; n = 29) bone mass groups) and 7 TS patients who maintained ovarian function (spontaneous menstrual cycle group (MC group)) as controls. We compared bone associated markers between the three groups (LB, NB, and MC). Furthermore, the LB group had concomitant treatment with eldecalcitol (ELD) and ERT for 12 months. The bone mineral density (BMD) of the lumber spine (L2-4) and the bone metabolism markers were then compared before and after the treatment. The bone metabolism markers were significantly higher in the LB group than the NB and MC groups. Furthermore, with the concomitant use of ELD and ERT in the LB group, BMD increased significantly (pre-treatment 0.710 ± 0.056 g/cm² vs. 0.736 ± 0.062 g/cm² after 12 months; p < 0.001). TS patients with insufficient bone mass acquisition even after ERT were characterized by a higher turnover in bone metabolism. Therefore, the concomitant use of ELD was considered an effective adjuvant therapy for increasing bone mass.

Incidence rate and characteristics of symptomatic vitamin D deficiency in children: a nationwide survey in Japan

There is concern that vitamin D deficiency is prevalent among children in Japan as well as worldwide. We conducted a nationwide epidemiologic survey of symptomatic vitamin D deficiency to observe its incidence rate among Japanese children. A questionnaire inquiring the number of new patients with vitamin D deficiency rickets and/or hypocalcemia for 3 years was sent to 855 randomly selected hospitals with a pediatrics department in Japan. In this survey, we found that 250 children were diagnosed with symptomatic vitamin D deficiency. The estimated number of patients with symptomatic vitamin D deficiency per year was 183 (95% confidence interval (CI): 145-222). The overall annual incidence rate among children under 15 years of age was 1.1 per 100,000 population (95% CI: 0.9-1.4). The second survey has provided detailed information on 89 patients with symptomatic vitamin D deficiency under 5 years of age in hospitals in the current research group. The nationwide and second surveys estimated the overall annual incidence rate of symptomatic vitamin D deficiency in children under 5 years of age to be 3.5 (2.7-4.2) per 100,000 population. The second survey revealed 83% had bowed legs, 88% had exclusive breastfeeding, 49% had a restricted and/or unbalanced diet and 31% had insufficient sun exposure among the 89 patients. This is the first nationwide survey on definitive clinical vitamin D deficiency in children in Japan. Elucidating the frequency and characteristics of symptomatic vitamin D deficiency among children is useful to develop preventative public health strategies.

Vitamin D Status and Its Association with Parathyroid Hormone Concentration in Brazilians

Vitamins are organic compounds that play a vital role in the control of metabolic processes. The D complex is considered a nutrient with a hormonal action and has an important participation in the constant maintenance of serum and extracellular calcium levels. The present study aims to analyze the results of 105.588 vitamin D (25(OH)D) measurements obtained from a database from a clinical analysis laboratory in Brazil, between the years of 2011 and 2013. The values of 25(OH)D were correlated with age, gender, and values of PTH. The results show a high prevalence of values of 25(OH)D considered inadequate, characterizing 76% of the studied population. It was observed that 26,5% of the individuals had deficiency and 49,5% had insufficiency of vitamin D. It was also shown that there was a negative correlation between 25(OH)D and PTH levels. In conclusion, this study is in accordance with others that show a high prevalence of vitamin D deficiency in different populations and alerts us for the importance of these measurements and analysis in clinical practice and as a base for diagnosis and treatment of hypovitaminosis.

Assessment criteria for vitamin D deficiency/insufficiency in Japan - proposal by an expert panel supported by Research Program of Intractable Diseases, Ministry of Health, Labour and Welfare, Japan, The Japanese Society for Bone and Mineral Research and The Japan Endocrine Society [Opinion]

Vitamin D is indispensable for the maintenance of bone and mineral health. Inadequate vitamin D action increases the risk for various musculoskeletal/mineral events including fracture, fall, secondary hyperparathyroidism, diminished response to antiresorptives, rickets/osteomalacia, and hypocalcemia. Its most common cause in recent years is vitamin D deficiency/insufficiency, clinically defined by low serum 25-hydroxyvitamin D [25(OH)D] level. Guidelines for vitamin D insufficiency/deficiency defined by serum 25(OH)D concentrations have been published all over the world. In Japan, however, the information on the associations between serum 25(OH)D and bone and mineral disorders has not been widely shared among healthcare providers, partly because its measurement had not been reimbursed with national medical insurance policy until August 2016. We have set out to collect and analyze Japanese data on the relationship between serum 25(OH)D concentration and bone and mineral events. Integrating these domestic data and published guidelines worldwide, here we present the following assessment criteria for vitamin D sufficiency/insufficiency/deficiency using serum 25(OH)D level in Japan. 1) Serum 25(OH)D level equal to or above 30 ng/mL is considered to be vitamin D sufficient. 2) Serum 25(OH)D level less than 30 ng/mL but not less than 20 ng/mL is considered to be vitamin D insufficient. 3) Serum 25(OH)D level less than 20 ng/mL is considered to be vitamin D deficient. We believe that these criteria will be clinically helpful in the assessment of serum 25(OH)D concentrations and further expect that they will form a basis for the future development of guidelines for the management of vitamin D deficiency/insufficiency.

Assessment criteria for vitamin D deficiency/insufficiency in Japan: proposal by an expert panel supported by the Research Program of Intractable Diseases, Ministry of Health, Labour and Welfare, Japan, the Japanese Society for Bone and Mineral Research and the Japan Endocrine Society [Opinion]

Vitamin D is indispensable for the maintenance of bone and mineral health. Inadequate vitamin D action increases the risk for various musculoskeletal/mineral events including fracture, fall, secondary hyperparathyroidism, diminished response to antiresorptives, rickets/osteomalacia, and hypocalcemia. Its most common cause in recent years is vitamin D deficiency/insufficiency, clinically defined by a low serum 25-hydroxyvitamin D [25(OH)D] level. Guidelines for vitamin D insufficiency/deficiency defined by serum 25(OH)D concentrations have been published all over the world. In Japan, however, the information on the associations between serum 25(OH)D and bone and mineral disorders has not been widely shared among healthcare providers, partly because its measurement had not been reimbursed with national medical insurance policy until August 2016. We have set out to collect and analyze Japanese data on the relationship between serum 25(OH)D concentration and bone and mineral events. Integrating these domestic data and published guidelines worldwide, here, we present the following assessment criteria for vitamin D sufficiency/insufficiency/deficiency using serum 25(OH)D level in Japan. (1) Serum 25(OH)D level equal to or above 30 ng/ml is considered to be vitamin D sufficient. (2) Serum 25(OH)D level less than 30 ng/ml but not less than 20 ng/ml is considered to be vitamin D insufficient. (3) Serum 25(OH)D level less than 20 ng/ml is considered to be vitamin D deficient. We believe that these criteria will be clinically helpful in the assessment of serum 25(OH)D concentrations and further expect that they will form a basis for the future development of guidelines for the management of vitamin D deficiency/insufficiency.