Poor Status of Vitamin D: A Survey of Area With Lowest Sunlight Radiation in Sichuan, China.

Objective: Vitamin D plays an important role in bone and mineral metabolism. Ultraviolet B (UVB) is the primary determinant for vitamin D synthesis. However, population-based data of vitamin D status was sparse in areas with sunlight deprivation in China. This study aimed to assess serum 25-hydroxyvitamin D [25(OH)D] levels among adult women in Sichuan basin with the lowest sunlight radiation in China, and the associations with sunlight exposure and age. Methods: In the context of the same ethnicity, similar latitude and lifestyle in sunlight-limited basin and sunlight-abundant plateau, 1,057 women in basin and 337 in plateau aged 29-95 years were included in this study, from November 2012 to February 2013. Daily sunlight exposure duration of previous month was obtained using questionnaires. Serum 25(OH)D was measured by enzyme-linked immunosorbent assay. Results: The prevalence of vitamin D severe deficiency [25(OH)D <30 nmol/L] and deficiency [30 ≤ 25(OH)D <50 nmol/L] was significantly higher in basin than plateau (21.85% vs. 10.09%, and 59.32% vs. 40.36%; P<0.0001). Women from basin exhibited lower serum 25(OH)D levels than those from plateau (40.66 ± 15.62 vs. 52.54 ± 19.94 nmol/L, P<0.0001). In basin, women more than 50 years old had higher 25(OH)D than younger counterparts, and 25(OH)D level of these groups was not associated with sunlight exposure duration. While in plateau, women younger than 60 years old had higher 25(OH)D than the older women. Furthermore, for those younger groups, women with long sunlight exposure (≥3 h daily) had higher 25(OH)D concentration than those with short sunlight exposure (<3 h daily). Serum PTH was negatively associated with 25(OH)D in basin, but not in plateau. Conclusions: Alarmingly high prevalence of vitamin D deficiency was observed in women in sunlight-deprived basin in Sichuan. Only the vitamin D status of younger women from plateau with adequate solar radiation could benefit from sunlight exposure. Vitamin D supplementation and vitamin D-fortified food should be encouraged to improve vitamin D status for women living in sunlight-limited areas, or with old age.

Sinonasal hemangiopericytoma caused hypophosphatemic osteomalacia: A case report.

RATIONALE: Tumor-induced osteomalacia (TIO) is a rare, paraneoplastic syndrome featured with fibroblast growth factor 23 (FGF23) secretion primarily by benign mesenchymal tumors and sometimes by malignancies. TIO diagnosis and treatment is often delayed because TIO usually has nonspecific generalized bone pain and weakness, and location of TIO tumor is quite challenging. Very few TIO caused by sinonasal hemangiopericytoma have been reported in the literature. PATIENT CONCERNS: A 40-year-old Chinese woman presented with diffuse bone pain for more than 1 year. Laboratory examination showed hypophosphatemia, hyperphosphaturia, hypocalcemia, an elevated serum alkaline phosphatase (ALP) level and bone-specific ALP level. Imaging studies revealed low bone mineral density (BMD) and multiple pseudofractures at the ribs. F-18 fluorodeoxyglucose positron emission tomography was negative in searching for tumors. Because no tumor was located, the patient was treated with oral phosphate, calcium, and alfacalcidol, and achieved great relief in her symptoms and improvement in BMD. Six years later, the patient had breast cancer surgery and received chemotherapy, and still had hypophosphatemia. During this time, nasopharyngo-fiberscope showed nasal mass in her left nasal cavity. Then she had her nasal polyps removed and surprisingly the serum phosphate became normal. DIAGNOSES AND INTERVENTIONS: The patient had the nasal mass resected, and pathological diagnosis of the nasal mass was sinonasal hemangiopericytoma. Immunohistochemical analysis was positive for FGF23. Thus the final diagnosis was osteomalacia induced by sinonasal hemangiopericytoma. Phosphate supplementation and alfacalcidol were discontinued. OUTCOMES: The patient had normal serum phosphate after 6-month follow-up. LESSONS: By presenting this case, we hope to remind clinicians that in patients with osteomalacia with undetermined reason and intranasal polypoid mass, sinonasal hemangiopericytoma should be suspected.

[Association of Serum Vitamin D with Hand-grip Strength and Balance Ability: a Cross-sectional Study on Community-dwelling Women in Sichuan, China].

OBJECTIVE: To determine the relationship between serum levels of 25(OH)D and 1, 25(OH)2 D and the hand-grip strength and balance ability of women in Sichuan, China. METHODS: A cross-sectional study on a representative sample of 1 095 women aged 29-95 yr. in Sichuan Province was undertaken. Their hand-grip strength and balance ability were assessed using a hand-held dynamometer and the short physical performance battery (SPPB), respectively. The participants were divided into four groups according to the level of serum 25(OH)D: sufficient (>75 nmol/L), insufficient (51-75 nmol/L), deficiency (25-50 nmol/L), and serious deficiency (<25 nmol/L). General liner models were established to compare the differences of the four groups in balance ability. Logistic regression models were established to examine the associations of serum 25(OH)D and 1, 25(OH)2 D withhand-grip strength and physical performance. RESULTS: About 70.9% of the participants had vitamin D deficiency. Those with vitamin D insufficiency or deficiency were more likely to reside in a higher latitudinal area (P<0.001), spend less time in outdoor activities (P=0.013), and take less vitamin D supplements (P<0.001). Older women (≥65 years) had lower serum 25(OH)D (P=0.001) and were more likely to have ≤50 nmol/L 25(OH)D than their younger counterparts (74.6% vs. 68.9%, P=0.046). However, no significant age differences were found in serum 1, 25(OH)2 D. Serum levels of 25(OH)D and 1, 25(OH)2 D were not found to be associated with hand-grip strength and balance ability after adjusting for confounding factors. Hand-grip strength and balance ability decreased with age (OR=1.066, P<0.001; OR=1.111, P<0.001). Higher body mas was associated with higher hand-grip strength (OR=0.958, P<0.001). Higher serum albumin (OR=0.896, P=0.001) and longer walking time (OR=0.799, P=0.001) were associated with higher balance ability. CONCLUSION: Serum levels of 25(OH)D and 1, 25(OH)2D are not associated with hand-grip strength and balance ability.

Clinical characteristics associated with bone mineral density improvement after 1-year alendronate/vitamin d3 or calcitriol treatment: Exploratory results from a phase 3, randomized, controlled trial on postmenopausal osteoporotic women in China.

Baseline and on-treatment characteristics, including age, obesity, calcium intake, and bone turnover markers, may predict the bone mineral density (BMD) response in women with postmenopausal osteoporosis (PMO) to 1 to 2 years of antiresorptive therapy and/or vitamin D supplementation. This study aimed to explore clinical characteristics associated with 12-month BMD improvement in Chinese women with postmenopausal osteoporosis (PMO).In this post hoc analysis of a previous phase 3 multicenter, randomized controlled trial, Chinese PMO women who were treated with once weekly alendronate 70 mg/vitamin D3 5600 IU (ALN/D5600) or once daily calcitriol 0.25 mcg, and had measurements of 1-year lumbar spine BMD (LS-BMD) and on-treatment bone turnover markers (BTMs) were included in the analysis.In Chinese PMO patients on ALN/D5600, 1-year LS-BMD change was negatively correlated with age (ß = -0.00084, P < .01), dietary calcium (ß = -0.0017, P = .07), and procollagen type 1 N-terminal propeptide (P1NP) change at month 6 (ß = -0.000469, P = .0016), but positively with body mass index (BMI) (ß = 0.00128, P = .08); baseline P1NP above the median was associated with a significantly greater BMD percentage change at the lumbar spine (P = .02) and the total hip (P = .0001). In the calcitriol group, a significant 1-year LS-BMD increase was associated with BMI (ß = 0.0023, P = .02), baseline P1NP (ß = 0.00035, P = .0067), history of prior vertebral fracture(s) (ß = 0.034, P < .0001) and baseline serum 25(OH)D level (ß = -0.00083, P = .02).The presented findings from Chinese postmenopausal osteoporotic women suggested clinically meaningful baseline and on-treatment characteristics predicting BMD improvement after 1 year of ALN/D5600 treatment, which differed from calcitriol treatment with baseline identifiable associations. The study remained exploratory and further accumulation of evidence is needed.

Effect of low-dose alendronate treatment on bone mineral density and bone turnover markers in Chinese postmenopausal women with osteopenia and osteoporosis.

OBJECTIVE: The aim of this study was to evaluate the effect of low-dose alendronate (ALN) treatment on bone mineral density (BMD) and bone turnover markers in Chinese postmenopausal women with osteopenia and osteoporosis. METHODS: This study was a large-sample, randomized, open-label, prospective, multicenter, clinical trial with a 12-month follow-up. A total of 639 postmenopausal women (aged 62.2 ± 7.0 y) with osteopenia or osteoporosis were randomized into two groups: low-dose ALN (70 mg every two weeks) and standard-dose ALN (70 mg weekly). All patients were also supplemented with calcium (600 mg) and vitamin D3 (125 IU) daily. BMD (measured by dual-energy x-ray absorptiometry; Hologic and Lunar) and levels of serum bone turnover markers (bone resorption marker, carboxy-telopeptide of type I collagen; bone formation marker, alkaline phosphatase) were assessed at baseline and at 3, 6, and 12 months of treatment. BMD and bone turnover markers were compared between the baseline and the end of treatment, and the changes in BMD and bone turnover markers were also compared between the low-dose ALN group and the standard-dose ALN group. RESULTS: No significant differences in age, years since menopause, body mass index, BMD, 25-hydroxy vitamin D level, and serum biochemical markers were found at baseline between the two dose groups. A total of 558 (87.3%) and 540 (84.5%) women completed the treatment at the 6th and 12th months, respectively. After the 12-month treatment, lumbar spine and hip BMD increased and serum bone turnover markers decreased significantly in both of the treatment groups (P < 0.01), and no differences in percentage changes in BMD at the lumbar spine, femoral neck, and hip were found between the low-dose group (5.60%, 3.87%, and 3.28%, respectively) and the standard-dose group (5.07%, 2.93%, and 3.80%, respectively; P > 0.05). However, levels of serum alkaline phosphatase and carboxy-telopeptide of type I collagen in the standard-dose group decreased moderately compared with those in the low-dose group (P < 0.05 and P < 0.01). The women tolerated the two doses of ALN quite well. Adverse effects were similar in the two groups. CONCLUSIONS: Treatment with low-dose ALN (70 mg every two weeks) in women with postmenopausal osteopenia or osteoporosis effectively increases lumbar spine and hip BMD, similar to treatment with standard-dose ALN. Low-dose ALN may be a cost-effective and safe protocol for treating osteopenia or osteoporosis in Chinese women.

Systematic review of soy isoflavone supplements on osteoporosis in women.

OBJECTIVE: To clarify the effect of soy isoflavones on prevention of osteoporosis, and the effective dosage of soy isoflavones and its duration. METHODS: Random control trials that investigated the association of soy isoflavones and osteoporosis were included in the meta-analysis by researching MEDLINE, EMBASE and the Chinese Biomedical Database up to October 2011. The Rev Man software was used for all of the statistical analysis. RESULTS: The present meta-analysis found that soy isoflavones significantly increased the bone mineral density by 54% and decreased the bone resorption marker urinary deoxypyridinoline (DPD) by 23% compared to baseline in women. Using random effects model, the effect of isoflavones on bone mineral density (BMD) regarding menopausal status and isoflavone dose revealed higher weighted mean difference changes were found in postmenopausal women and isoflavone dose above 75 mg/d. Subgroup analysis of trials with menopausal status, supplement type, isoflavone dose and intervention duration that used soy isoflavone extracts resulted in significant different overall effect of DPD using by random effects model. Sensitivity analysis indicated that the effect of soy isoflavones on BMD and DPD was robust. CONCLUSIONS: The present meta-analysis reveals that soy isoflavone supplements significantly increase bone mineral density and decrease the bone resorption marker urinary DPD. It shows no significant effect on bone formation markers serum bone alkaline phosphatase. The significant effect of soy isoflavones on BMD and urinary DPD is relative to menopausal status, supplement type, isoflavone dose and intervention duration.