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1.
R. Przybelski S. Agrawal D. Krueger J. A. Engelke F. Walbrun N. Binkley 《Osteoporosis international》2008,19(11):1621-1628
Summary This prospective study finds that ergocalciferol 50,000 IU three times weekly for four weeks effectively and safely corrects
vitamin D inadequacy in nursing home residents.
Introduction Low vitamin D status is common among nursing home residents and contributes to bone loss, falls and fractures. The objective
of this study was to evaluate the efficacy and safety of short course, high dose, oral vitamin D2 (ergocalciferol) treatment.
Methods This prospective study included 63 nursing home residents. The 25 with low vitamin D status (serum 25(OH)D ≤ 25 ng/ml) received
oral ergocalciferol 50,000 IU three times weekly for four weeks; the others received no change to their routine care. Serum
total 25(OH)D, 25(OH)D2, 25(OH)D3, calcium, parathyroid hormone (PTH), bone turnover markers and neuro-cognitive assessments were obtained at baseline and
four weeks.
Results Mean total 25(OH)D concentration increased (p < 0.0001) from 17.3 to 63.8 ng/ml in the treated group and remained unchanged
in the comparison group. Serum 25(OH)D3 remained stable in the comparison group, but declined (p < 0.0001) with D2 treatment from 15.4 to 9.1 ng/ml. Serum PTH trended down in the treatment group (p = 0.06). No treatment-induced improvement
in ambulation, cognition or behavior was observed. No hypercalcemia or other adverse effects were observed with ergocalciferol
treatment.
Conclusion Four weeks of oral vitamin D2 supplementation effectively and safely normalizes serum 25(OH)D in nursing home residents. 相似文献
2.
Goldner WS Stoner JA Lyden E Thompson J Taylor K Larson L Erickson J McBride C 《Obesity surgery》2009,19(2):173-179
Background Vitamin D deficiency is common following bariatric surgery and is due to a combination of baseline deficiency and postoperative
malabsorption. There are few prospective studies evaluating the appropriate dose of vitamin D to prevent and treat vitamin
D deficiency following bariatric surgery.
Methods We evaluated three doses of vitamin D3 (800, 2,000, and 5,000 IU/day) in a prospective, randomized pilot trial of 45 patients
undergoing Roux-en-Y gastric bypass. Serum 25 hydroxy Vitamin D (25OHD), intact PTH (iPTH), calcium, and urine calcium/creatinine
ratios were measured at 6, 12, and 24 months postoperatively. Due to a high dropout rate at 24 months, we focus on the 12-month
data.
Results At 12 months, the 800-, 2,000-, and 5,000-IU groups had a mean ± SD increase in 25OHD of 27.5 ± 40.0, 60.2 ± 37.4, and 66.1 ± 42.2 nmol/L,
respectively (p = 0.09) with a maximum increase in each group of 87.4, 114.8, and 129.8 nmol/L. Forty-four percent, 78%, and 70% achieved
25OHD levels ≥75 nmol/L (p = 0.38). Results for the 6- and 24-month time points were similar to the 12-month results. Mean weight loss at 24 months
of the study was not different among groups (p = 0.52). Serum calcium did not change significantly, and there were no cases of hypercalcemia or sustained hypercalciuria.
Conclusions Higher doses of vitamin D supplementation trend towards higher levels of 25OHD. Vitamin D replacement as high as 5,000 IU
/day is safe and necessary in many patients to treat vitamin D deficiency following Roux-en-Y gastric bypass yet is still
suboptimal in others. 相似文献
3.
C. J. Bacon G. D. Gamble A. M. Horne M. A. Scott I. R. Reid 《Osteoporosis international》2009,20(8):1407-1415
Summary Daily dosing with vitamin D often fails to achieve optimal outcomes, and it is uncertain what the target level of 25-hydroxyvitamin
D should be. This study found that large loading doses of vitamin D3 rapidly and safely normalize 25OHD levels, and that monthly dosing is similarly effective after 3–5 months. With baseline
25OHD > 50 nmol/L, vitamin D supplementation does not reduce PTH levels.
Introduction There is concern that vitamin D supplementation doses are frequently inadequate, and that compliance with daily medication
is likely to be suboptimal.
Methods This randomized double-blind trial compares responses to three high-dose vitamin D3 regimens and estimates optimal 25-hydroxyvitamin D (25OHD) levels, from changes in parathyroid hormone (PTH), and procollagen
type I amino-terminal propeptide (P1NP) in relation to baseline 25OHD. Sixty-three elderly participants were randomized to
three regimens of vitamin D supplementation: a 500,000-IU loading dose; the loading dose plus 50,000 IU/month; or 50,000 IU/month.
Results The Loading and Loading + Monthly groups showed increases in 25OHD of 58 ± 28 nmol/L from baseline to 1 month. Thereafter,
levels gradually declined to plateaus of 69 ± 5 nmol/L and 91 ± 4 nmol/l, respectively. In the Monthly group, 25OHD reached
a plateau of ~80 ± 20 nmol/L at 3–5 months. There were no changes in serum calcium concentrations. PTH and P1NP were only
suppressed by vitamin D treatment in those with baseline 25OHD levels <50 and <30 nmol/L, respectively.
Conclusions Large loading doses of vitamin D3 rapidly and safely normalize 25OHD levels in the frail elderly. Monthly dosing is similarly effective and safe, but takes
3–5 months for plateau 25OHD levels to be reached. 相似文献
4.
S. Iuliano-Burns X. F. Wang J. Ayton G. Jones E. Seeman 《Osteoporosis international》2009,20(9):1523-1528
Summary Serum 25(OH)D levels decline without sunlight exposure. We studied 120 expeditioners to Antarctica to determine the skeletal
and hormonal responses to sunlight deprivation. With emerging vitamin D insufficiency, serum calcium decreased, PTH increased,
and bone loss at the proximal femur was observed. Baseline serum 25(OH)D levels >100 nmol/L prevented vitamin D insufficiency.
Introduction Vitamin D stores deplete without adequate sunlight exposure unless supplementation is provided. We studied 120 healthy adults
who spent a year in Antarctica as a model for sunlight deprivation to define the timing and magnitude of the skeletal and
hormonal responses to emerging vitamin D insufficiency.
Methods Fasting blood samples were assessed at baseline, 6 and 12 months for serum 25-hydroxyvitamin D (25(OH)D), osteocalcin (OC),
bone formation (P1NP) and resorption (CTx), PTH and calcium. Lumbar spine and proximal femur BMD was measured using DXA. Differences
over time were determined using repeated measures ANOVA. Percent changes were expressed as (Δ value/(value A + value B)/2) × 100. Relationships between outcome measures were determined using Spearman’s correlations.
Results Vitamin D insufficiency (<50 nmol/L) was observed in 85% of expeditioners by 6 months when serum calcium decreased and PTH
increased (p < 0.01). By 12 months, OC increased by 7.4 ± 3.0% (p < 0.05), and BMD decreased by 1.0 ± 2.0% at the total proximal femur (p < 0.05). For those with vitamin D sufficiency at baseline (>50 nmol/L), sunlight deprivation produced vitamin D insufficiency
within 4 months unless baseline values were >100 nmol/L.
Conclusion Supplementation may be necessary for expeditioners with limited access to UV light. 相似文献
5.
Monica L. Nelson M.P.H. R.D. Lynn M. Bolduc M.S. R.D. C.D.E. Michelle E. Toder M.D. F.A.C.S. Donald M. Clough M.D. F.A.C.S. Susan S. Sullivan D.Sc. R.D. 《Surgery for obesity and related diseases》2007,3(4):138-437
BACKGROUND: To evaluate the adequacy of supplementation to correct preoperative vitamin D deficiency in adult patients during the year after Roux-en-Y gastric bypass (RYGB) surgery. METHODS: The medical records were reviewed and the preoperative and 12-month postoperative serum 25-hydroxyvitamin D [25(OH)D] levels were compared in patients who underwent RYGB from 2002 to 2004. The serum 25(OH)D levels were defined as being optimal (> or = 80 nmol/L), suboptimal (50-79 nmol/L), or deficient (<50 nmol/L). Patients with deficient 25(OH)D levels were prescribed 50,000 IU ergocalciferol weekly. The remaining patients averaged 710 IU supplemental vitamin D intake daily. RESULTS: The mean patient age was 43.8 +/- 10.7 years, and the mean preoperative body mass index was 51.8 +/- 9.8 kg/m2. Of the 95 patients with baseline and 12-month 25(OH)D levels, 89% were women. The mean preoperative 25(OH)D level was 49.7 +/- 26.5 nmol/L; 34% had suboptimal 25(OH)D levels and 54% had deficient levels before surgery. Twelve months after surgery, those receiving 50,000 IU weekly (n = 40) had a mean 25(OH)D level of 69.2 +/- 22.2 nmol/L; 63% had suboptimal and 8% deficient levels. Those taking 710 IU daily (n = 55) had a mean 25(OH)D level of 85.5 +/- 33.0 nmol/L; 44% had suboptimal and 6% deficient levels. CONCLUSION: Vitamin D deficiency is prevalent in RYGB patients before surgery. The vitamin D status improved markedly after RYGB surgery with either 710 IU vitamin D daily or 50,000 IU weekly. Current supplementation practices do not appear to optimize the serum 25(OH)D levels and need to be more closely examined. 相似文献
6.
Nakamura K Nashimoto M Tsuchiya Y Saito T Nishiwaki T Ueno K Okuda Y Oshiki R Yamamoto M 《Journal of bone and mineral metabolism》2006,24(5):395-400
This study was designed to determine the threshold value for 25-hydroxyvitamin D [25(OH)D] concentration in relation to elevated
serum parathyroid hormone (PTH) concentrations in elderly Japanese women. The subjects were 582 noninstitutionalized, ambulant
women who lived in a community in Japan. Serum 25(OH)D concentrations were determined using the Nichols Advantage chemiluminescent
assay, and serum intact PTH concentrations were determined with a two-site immunoradiometric assay. Demographic characteristics,
calcium intake, and serum 1,25(OH)2D levels were also determined. The average age, body mass index (BMI), and calcium intake of the subjects were 74.5 years
(SD 4.5), 23.3 kg/m2 (SD 3.4), and 579 mg/day (SD 248), respectively. The serum log-transformed intact PTH concentration was significantly predicted
by the serum 25(OH)D concentration (r = −0.147, P = 0.0004), but not by age, BMI, the serum log-transformed 1,25(OH)2D concentration, or the log-transformed calcium intake. Analysis of variance with Dunnett's multiple comparisons showed that
mean serum intact PTH concentrations with serum 25(OH)D concentrations less than 30 nmol/l (mean intact PTH = 5.89 pmol/l,
P < 0.0001) and in the range 30–39 nmol/l (mean intact PTH = 4.54 pmol/l, P = 0.0067) were significantly higher than mean intact PTH concentrations for serum 25(OH)D concentrations greater than 50 nmol/l
(mean intact PTH = 3.65 pmol/l, the baseline level), but the mean serum intact PTH concentration for 25(OH)D concentrations
in the range 40–49 nmol/l (mean intact PTH = 3.70 pmol/l, P = 0.9975) was not. We conclude that serum 25(OH)D for ambulant elderly Japanese women should be maintained at 40 nmol/l or
higher. 相似文献
7.
To date, no study has investigated the nutritional status of vitamin D in frail elderly people living at home. The purposes
of this study were to assess serum 25-hydroxyvitamin D (25[OH]D) levels and associated factors in noninstitutionalized elderly
people who had various levels of physical disability, and to propose an adequate vitamin D nutritional status for the elderly
by interpreting the serum 25(OH)D levels in relation to serum parathyroid hormone (PTH) levels in this population. Health
examinations were conducted in the winter and summer of 2003. The subjects were 143 elderly people in the winter, and 120
elderly people in the summer, who all used the long-term care insurance system at home. Serum 25(OH)D concentrations were
determined with a chemiluminescence protein-binding assay, and serum intact PTH concentrations were determined with an immunoradiometric
assay. The subjects' disease histories and lifestyle information were obtained through an interview. Activities of daily living
(ADL) levels were evaluated using the Barthel index, and grip strength was measured with a digital hand dynamometer. Average
serum 25(OH)D levels in the winter and summer were 54.2 nmol/l (SD 29.0) and 53.3 nmol/l (SD 32.3), respectively, and intact
PTH concentrations in the winter and summer were 4.2 pmol/l (SD 1.8) and 4.3 pmol/l (SD 1.8), respectively. The proportion
of people who had a low 25(OH)D (<30 nmol/l) and high intact PTH levels (>6.9 pmol/l) were 15%–20% and 8%, respectively. Significant
predictors of low serum 25(OH)D concentrations were low ADL levels, female sex, and low fish consumption in both seasons.
Serum 25(OH)D concentrations of less than 50 nmol/l were associated with elevated serum intact PTH concentrations. In conclusion,
elderly people requiring care at home are at high risk of hypovitaminosis D, and their low serum 25(OH)D levels are mainly
associated with low ADL levels. In addition, maintenance of serum 25(OH)D concentrations above 50 nmol/l may prevent hypovitaminosis
D-induced hyperparathyroidism. 相似文献
8.
Papapetrou PD Triantaphyllopoulou M Karga H Zagarelos P Aloumanis K Kostakioti E Vaiopoulos G 《Journal of bone and mineral metabolism》2007,25(3):198-203
Vitamin D deficiency characterized by low 25-hydroxyvitamin D [25(OH)D] levels has been found to be prevalent among the elderly
in many regions of the world. To investigate the vitamin status in elderly community-living persons in Athens, we measured
25(OH)D and parathyroid hormone (PTH) in elderly persons and young blood donors during the winter and summer. The changes
in these parameters in a subgroup of the elderly were studied longitudinally. The blood donors had mean 25(OH)D levels similar
in winter and summer and twice as high in winter compared to the elderly. At the end of the winter, about 20% of the elderly
had severe vitamin D deficiency, with 25(OH)D below 25 nmol/l, and only 6.5% could be judged as vitamin D sufficient with
values above 80 nmol/l. The situation improved during summer, although 64.8% of the elderly continued to have levels below
80 nmol/l. Mean plasma PTH in the elderly in summer was not different from that of blood donors; however, it was doubled during
the winter. Regression of PTH on 25(OH)D demonstrated that PTH starts to rise when 25(OH)D falls below approximately 80 nmol/l.
We conclude that severe vitamin deficiency associated with secondary hyperparathyroidism is not uncommon in the elderly in
Athens during the winter; it subsides during summer, although only one-third of the elderly population attain vitamin D sufficiency
during summer. We found that a threshold value of 25(OH)D exists at approximately 80 nmol/l, below which secondary hyperparathyroidism
ensues, as described previously. 相似文献
9.
Unusually prolonged vitamin D intoxication after discontinuation of vitamin D: possible role of primary hyperparathyroidism 总被引:1,自引:1,他引:0
A 77-year-old woman had taken 50,000 IU of vitamin D2 daily, instead of once weekly, for over 2 years. She developed severe hypercalcemia, and after stopping vitamin D, her serum 25-hydroxyvitamin D (25(OH)D) remained higher than 250 nmol/l for almost 2(1/2) years. Inappropriately high parathyroid (PTH) concentrations were particularly evident after serum calcium was suppressed to slightly above the reference range by the administration of intravenous pamidronate and prednisone. It seems that an underlying primary hyperparathyroidism that was masked initially by the hypercalcemia of vitamin D intoxication was responsible for the unusually prolonged half-life of 25(OH)D in the blood. After vitamin D2 had been stopped, the decline in serum 25(OH)D was unusually slow. In this unusual case, primary hyperparathyroidism probably prevented an appropriate increase in the vitamin D-catabolizing enzyme, 25(OH)D-24-hydroxylase, thereby slowing metabolic clearance of 25(OH) vitamin D. 相似文献
10.
Vitamin D, parathyroid hormone levels and bone mineral density in community-dwelling older women: The Rancho Bernardo Study 总被引:3,自引:3,他引:0
Denise G. von Mühlen Gail A. Greendale Cedric F. Garland Lori Wan Elizabeth Barrett-Connor 《Osteoporosis international》2005,16(12):1721-1726
Vitamin D (25(OH)D) increases the efficiency of intestinal calcium absorption. Low levels of serum calcium stimulate the secretion of parathyroid hormone (PTH), which maintains serum calcium levels at the expense of increased bone turnover, bone loss and increased risk of fractures. We studied the association between 25(OH)D and PTH levels, and their associations with bone mineral density (BMD), bone loss, and prevalence of hip fractures in 615 community-dwelling postmenopausal aged 50–97 years. Mean level of 25(OH)D and PTH were 102.0 nmol/l±35.0 nmol/l and 49.4 ng/l±23.2 nmol/l, respectively; 49% of women were current hormone therapy users. The overall prevalence of vitamin D insufficiency (25(OH)D<50 nmol/l) was 2%, and prevalence of high PTH levels (>65 ng/l) was 17.4%. In multiple linear regression analyses hip BMD was negatively and independently associated with PTH levels ( p =0.04), and positively and independently associated with 25(OH)D levels ( p =0.03). There were only 23 women (3.7%) who experienced a hip fracture. In age-adjusted analyses there were no significant differences of 25(OH)D and PTH levels by hip fracture status. Across the entire range of values, the overall correlation between 25(OH)D and PTH was moderate ( r =–0.20). However, after the threshold vitamin D level of 120 nmol/l, all PTH values were below 65 ng/l. Further studies are necessary to identify the optimal vitamin D levels necessary to prevent secondary hyperparathyroidism. 相似文献
11.
Berger C Greene-Finestone LS Langsetmo L Kreiger N Joseph L Kovacs CS Richards JB Hidiroglou N Sarafin K Davison KS Adachi JD Brown J Hanley DA Prior JC Goltzman D;CaMos Research Group 《Journal of bone and mineral research》2012,27(6):1381-1389
Vitamin D is essential for facilitating calcium absorption and preventing increases in parathyroid hormone (PTH), which can augment bone resorption. Our objectives were to examine serum levels of 25-hydroxyvitamin D [25(OH)D] and PTH, and factors related to longitudinal change in a population-based cohort. This is the first longitudinal population-based study looking at PTH and 25(OH)D levels. We analyzed 3896 blood samples from 1896 women and 829 men in the Canadian Multicentre Osteoporosis Study over a 10-year period starting in 1995 to 1997. We fit hierarchical models with all available data and adjusted for season. Over 10 years, vitamin D supplement intake increased by 317 (95% confidence interval [CI] 277 to 359) IU/day in women and by 193 (135 to 252) IU/day in men. Serum 25(OH)D (without adjustment) increased by 9.3 (7.3 to 11.4) nmol/L in women and by 3.5 (0.6 to 6.4) nmol/L in men but increased by 4.7 (2.4 to 7.0) nmol/L in women and by 2.7 (-0.6 to 6.2) nmol/L in men after adjustment for vitamin D supplements. The percentage of participants with 25(OH)D levels <50 nmol/L was 29.7% (26.2 to 33.2) at baseline and 19.8% (18.0 to 21.6) at year 10 follow-up. PTH decreased over 10 years by 7.9 (5.4 to 11.3) pg/mL in women and by 4.6 (0.2 to 9.0) pg/mL in men. Higher 25(OH)D levels were associated with summer, younger age, lower body mass index (BMI), regular physical activity, sun exposure, and higher total calcium intake. Lower PTH levels were associated with younger age and higher 25(OH)D levels in both women and men and with lower BMI and participation in regular physical activity in women only. We have observed concurrent increasing 25(OH)D levels and decreasing PTH levels over 10 years. Secular increases in supplemental vitamin D intake influenced both changes in serum 25(OH)D and PTH levels. 相似文献
12.
M. Pfeifer B. Begerow H. W. Minne K. Suppan A. Fahrleitner-Pammer H. Dobnig 《Osteoporosis international》2009,20(2):315-322
Summary In 242 community-dwelling seniors, supplementation with either 1000 mg of calcium or 1000 mg of calcium plus vitamin D resulted
in a decrease in the number of subjects with first falls of 27% at month 12 and 39% at month 20. Additionally, parameters
of muscle function improved significantly.
Introduction The efficacy of vitamin D and calcium supplementation on risk of falling in the elderly is discussed controversially. Randomized
controlled trials using falls as primary outcome are needed. We investigated long-term effects of calcium and vitamin D on
falls and parameters of muscle function in community-dwelling elderly women and men.
Methods Our study population consisted of 242 individuals recruited by advertisements and mailing lists (mean [ ± SD] age, 77 ± 4 years).
All serum 25-hydroxyvitamin D (25[OH]D) levels were below 78 nmol/l. Individuals received in a double blinded fashion either
1000 mg of calcium or 1000 mg of calcium plus 800 IU of vitamin D per day over a treatment period of 12 months, which was
followed by a treatment-free but still blinded observation period of 8 months. Falls were documented using diaries. The study
took place in Bad Pyrmont, Germany (latitude 52°) and Graz, Austria (latitude 46°).
Results Compared to calcium mono, supplementation with calcium plus vitamin D resulted in a significant decrease in the number of
subjects with first falls of 27% at month 12 (RR = 0.73; CI = 0.54–0.96) and 39% at month 20 (RR = 0.61; CI = 0.34–0.76).
Concerning secondary endpoints, we observed significant improvements in quadriceps strength of 8%, a decrease in body sway
of 28%, and a decrease in time needed to perform the TUG test of 11%.
Discussion Combined calcium and vitamin D supplementation proved superior to calcium alone in reducing the number of falls and improving
muscle function in community-dwelling older individuals.
Parts of this work were presented as oral presentations at the 26th Annual Meeting of the American Society for Bone and Mineral
Research (ASBMR) in Seattle, Washington, October 2004 and at the IOF World Congress on Osteoporosis in Toronto, Canada, June
2006. 相似文献
13.
《Surgery for obesity and related diseases》2007,3(4):434-437
BackgroundTo evaluate the adequacy of supplementation to correct preoperative vitamin D deficiency in adult patients during the year after Roux-en-Y gastric bypass (RYGB) surgery.MethodsThe medical records were reviewed and the preoperative and 12-month postoperative serum 25-hydroxyvitamin D [25(OH)D] levels were compared in patients who underwent RYGB from 2002 to 2004. The serum 25(OH)D levels were defined as being optimal (≥80 nmol/L), suboptimal (50–79 nmol/L), or deficient (<50 nmol/L). Patients with deficient 25(OH)D levels were prescribed 50,000 IU ergocalciferol weekly. The remaining patients averaged 710 IU supplemental vitamin D intake daily.ResultsThe mean patient age was 43.8 ± 10.7 years, and the mean preoperative body mass index was 51.8 ± 9.8 kg/m2. Of the 95 patients with baseline and 12-month 25(OH)D levels, 89% were women. The mean preoperative 25(OH)D level was 49.7 ± 26.5 nmol/L; 34% had suboptimal 25(OH)D levels and 54% had deficient levels before surgery. Twelve months after surgery, those receiving 50,000 IU weekly (n = 40) had a mean 25(OH)D level of 69.2 ± 22.2 nmol/L; 63% had suboptimal and 8% deficient levels. Those taking 710 IU daily (n = 55) had a mean 25(OH)D level of 85.5 ± 33.0 nmol/L; 44% had suboptimal and 6% deficient levels.ConclusionVitamin D deficiency is prevalent in RYGB patients before surgery. The vitamin D status improved markedly after RYGB surgery with either 710 IU vitamin D daily or 50,000 IU weekly. Current supplementation practices do not appear to optimize the serum 25(OH)D levels and need to be more closely examined. 相似文献
14.
R. Patel D. Collins S. Bullock R. Swaminathan G. M. Blake I. Fogelman 《Osteoporosis international》2001,12(4):319-325
Vitamin D status is known to be an important determinant of bone mineral density (BMD). There is a significant seasonal variation
in serum vitamin D, and some studies have reported an associated seasonal variation in BMD. The present study was devised
to investigate whether a seasonal variation in BMD could be detected in healthy normal subjects, along with associated variations
in serum parathyroid hormone (PTH), intestinal calcium absorption and biochemical markers of bone turnover. A second aim was
to investigate whether, if such variations were identified, they could be suppressed by vitamin D supplementation. The subjects
were 70 healthy female volunteers (mean age 47.2 years, range 24–70 years) recruited into a double-masked crossover study
and followed over 2 years. During the first year 35 subjects received a daily oral supplement containing 800 IU (20 mg) cholecalciferol
(group 1) and 35 subjects received a placebo preparation (group 2). During the second year the treatment each group received
was reversed. Lumbar spine (L1–L4), left proximal femur and total body BMD were measured by DXA at 3-month intervals. Serum
25-hydroxyvitamin D (25-OHD), serum PTH, bone markers (bone-specific ALP (BSAP) and urinary crosslinks (DYPD/creatinine))
and calcium absorption were also measured at each visit. Cholecalciferol treatment increased serum 25-OHD by 25.4 nmol/l (p <0.001), while a reciprocal decrease in serum PTH of 6.6 ng/l (p = 0.011) was seen in subjects in the lowest quartile of baseline serum 25-OHD. The treatment had no significant effect on
spine, femur or total body BMD, calcium absorption or bone markers. When Fourier analysis was used to analyze the data for
seasonal effect (defined as twice the amplitude of the 1-year period variation) a highly significant effect for 25-OHD of
18 nmol/l (p <0.001) was found. However, no effect was found for BMD, PTH, calcium absorption or bone markers. The analysis set a 95%
confidence limit to the seasonal effect of less than 0.6% for spine, total hip and total body BMD. It was concluded that in
the population of healthy women studied there was no evidence of seasonal variation in spine, femur or total body BMD, serum
PTH, calcium absorption or bone markers. Vitamin D supplementation was found to have no effect on BMD.
Received: 7 July 2000 / Accepted: 14 November 2000 相似文献
15.
Low levels of 25-hydroxy vitamin D are associated with elevated parathyroid hormone in healthy adolescent females 总被引:1,自引:0,他引:1
This study aimed to investigate the relationship between 25-hydroxyvitamin D [25(OH)D)] and parathyroid hormone (PTH) levels in adolescent females residing in a northern climate. Concern regarding vitamin D status in this population is due to limited sunlight exposure in northern latitudes, decreased outdoor recreational activities, as well as decreased conversion in black girls from increased skin pigmentation. In this cross-sectional analysis, serum samples were assayed for 25(OH)D using competitive protein binding (CPB) assay and PTH with immuno-radiometric (RIA) procedures. Four hundred postmenarcheal females (12–18 years) residing in northeastern Ohio were recruited. Subjects were excluded if they had a history of bone, kidney, or liver disease, or used medications that affect bone. The primary goal was to determine serum 25(OH)D concentrations in relation to circulating PTH levels in a population of adolescent girls. The Spearman correlation test was used to compare PTH and 25(OH)D. Fit multiple split models were run to determine change in slope of the regression line when 25(OH)D and PTH were plotted. Analysis of variance was determined using modeled means with differences by race and season in the final model. Unadjusted mean serum 25(OH)D and PTH levels were 55.0±30.4 nmol/l and 39.4±20.6 ng/l, respectively. Blacks had lower 25(OH)D and higher PTH compared with non-blacks (P<0.0001), especially during the winter months. Decreasing 25(OH)D was inversely correlated with PTH (r=–0.314) (P<0.0001), and at concentrations of 25(OH)D 90 nmol/l, an increase in PTH was observed. Adolescents are at risk for decreased serum 25(OH)D concentrations, especially black girls. We found that the widely used cutoff for vitamin D deficiency is associated with increasing PTH levels and is below the inflection point for a change in the slope of the regression line. Our results support the need for further research to establish optimal vitamin D status in adolescent girls. 相似文献
16.
G. Guardia N. Parikh T. Eskridge E. Phillips G. Divine D. Sudhaker Rao 《Osteoporosis international》2008,19(1):13-19
Summary We assessed vitamin D nutritional status in unselected consecutive patients seeking advice on osteoporosis. The prevalence
of vitamin D depletion ranged from 15–72% depending upon the cut-off levels used for serum 25-hydroxyvitamin D, and the prevalence
did not change over the 5 years of the study.
Introduction Vitamin D depletion is a significant public health problem and has been studied in different populations using different cut-off
levels, but the optimal level is yet to be established.
Methods In a cross-sectional study of 2924 patients seen for osteoporosis advice we determined the prevalence of vitamin D depletion,
as assessed by 25-hydroxyvitamin D (25-OHD), using three different cut-off levels stratified by gender, race and the year
of the study over 5 years.
Results Mean age was 68.3 ± 10.0 years; 90% women and 88% white. Mean 25-OHD level was 24.6 ± 10 ng/ml and mean PTH was 48.4 ± 32 pg/ml.
The prevalence of vitamin D depletion was 15% with a cut-off level of <15 ng/ml, and rose to 32% and 72% with cut-off levels
<20 ng/ml and <30 ng/ml, respectively. The prevalence was higher in men and blacks and remained constant over 5 years, regardless
of the cut-off level. The expected inverse relationship between 25-OHD and PTH was observed irrespective of gender or ethnicity.
Conclusions The prevalence of vitamin D depletion in patients seeking advice for osteoporosis is high and did not change over the 5 years
of the study. 相似文献
17.
H. A. Bischoff-Ferrari 《Osteoporosis international》2007,18(4):401-407
The dose of vitamin D in the management of osteoporosis should be no less than 700–800 IU per day. An optimal dose of vitamin
D should raise serum concentrations of 25(OH)D to the desirable range of at least 75 nmol/l. Higher intermittent oral doses
of vitamin D may overcome low adherence. Vitamin D supplementation in the management of osteoporosis holds a significant public
health potential because of its low cost, excellent tolerability, and combined musculo-skeletal benefits. Fall and fracture
prevention with vitamin D is especially appealing in the treatment of older individuals at risk for fall-related fractures.
However, bone density, strength, and function benefits with vitamin D include active and inactive subgroups of community-dwelling
older men and women. Based on a recent expert panel and supportive evidence presented in this review, serum concentrations
of at least 75 nmol/l 25(OH)D will be referred to as desirable. Today, desirable serum 25(OH)D levels of at least 75 nmol/l
may only be reached in about one third of US older individuals and even fewer European older individuals. Two main factors
discussed in this review may help public health efforts to ensure desirable vitamin D levels for fall and fracture prevention,
including (1) a sufficient dose of vitamin D and (2) improved adherence to supplementation. 相似文献
18.
Summary This study reports on oral treatment with different doses of vitamin D3 ranging from 25 to 200 μg in females with 25-hydroxyvitamin
D3 levels < 60 nmol/L screened for participation in an osteoporosis trial. A guidance to safely and efficiently achieve 25-hydroxyvitamin
D3 levels > 60 nmol/L is presented.
Introduction The importance of vitamin D for skeletal health has been implemented in clinical trials in osteoporosis. The threshold of
25-hydroxyvitamin D for inclusion has changed from 30 to 60 nmol/L. This study reports on oral treatment with different doses
of vitamin D3 in females with 25-hydroxyvitamin D3 levels < 60 nmol/L.
Methods In 131 postmenopausal females screened for participation in an osteoporosis trial, the 25-hydroxyvitamin D3 concentration
was < 60 nmol/L. They were treated with 25 (n = 22), 50 (n = 19), 75 (n = 19), 100 (n = 41) or 200 μg (n = 30) of vitamin D3 daily for at least 10 days.
Results In the females treated with 25, 50, 75, 100 and 200 μg of vitamin D3 daily the 25-hydroxyvitamin D3 concentrations increased
significantly from 32.4 ± 2.7 (mean ± SEM) to 50.8 ± 2.9, from 46.7 ± 2.8 to 65.8 ± 2.6, from 41.6 ± 2.7 to 67.4 ± 2.9, from
46.7 ± 1.4 to 64.4 ± 2.2 and from 42.1 ± 2.0 to 71.2 ± 2.8 nmol/L, respectively (p < 0.001). S-calcium increased significantly but within the reference range (p < 0.006).
Conclusion Oral vitamin D3 safely increased 25-hydroxyvitamin D3 concentrations in all females above 60 nmol/L. This study demonstrates
how to achieve the new recommended 25-hydroxyvitamin D concentrations within the screening period of a clinical trial. 相似文献
19.
Lorna S Aucott Alison J Black William D Fraser Alexandra Mavroeidi David M Reid Karen R Secombes William G Simpson Frank Thies 《Journal of bone and mineral research》2013,28(10):2202-2213
Few year‐long vitamin D supplementation trials exist that match seasonal changes. The aim of this study was to determine whether daily oral vitamin D3 at 400 IU or 1000 IU compared with placebo affects annual bone mineral density (BMD) change in postmenopausal women in a 1‐year double‐blind placebo controlled trial in Scotland. White women aged 60 to 70 years (n = 305) were randomized to one of two doses of vitamin D or placebo. All participants started simultaneously in January/February 2009, attending visits at bimonthly intervals with 265 (87%) women attending the final visit and an additional visit 1 month after treatment cessation. BMD (Lunar iDXA) and 1,25‐dihydroxyvitamin D[1,25(OH)2D], N‐terminal propeptide of type 1 collagen [P1NP], C‐terminal telopeptide of type I collagen [CTX], and fibroblast growth factor‐23 [FGF23] were measured by immunoassay at the start and end of treatment. Circulating PTH, serum Ca, and total 25‐hydroxyvitamin D [25(OH)D] (latter by tandem mass spectrometry) were measured at each visit. Mean BMD loss at the hip was significantly less for the 1000 IU vitamin D group (0.05% ± 1.46%) compared with the 400 IU vitamin D or placebo groups (0.57% ± 1.33% and 0.60% ± 1.67%, respectively) (p < 0.05). Mean (± SD) baseline 25(OH)D was 33.8 ± 14.6 nmol/L; comparative 25(OH)D change for the placebo, 400 IU, and 1000 IU vitamin D groups was ?4.1 ± 11.5 nmol/L, +31.6 ± 19.8 nmol/L, and +42.6 ± 18.9 nmol/L, respectively. Treatment did not change markers of bone metabolism, except for a small reduction in PTH and an increase in serum calcium (latter with 1000 IU dose only). The discordance between the incremental increase in 25(OH)D between the 400 IU and 1000 IU vitamin D and effect on BMD suggests that 25(OH)D may not accurately reflect clinical outcome, nor how much vitamin D is being stored. © 2013 American Society for Bone and Mineral Research. 相似文献
20.
Prevalence of Vitamin D Insufficiency in an Adult Normal Population 总被引:14,自引:5,他引:9
M.-C. Chapuy P. Preziosi M. Maamer S. Arnaud P. Galan S. Hercberg P.J. Meunier 《Osteoporosis international》1997,7(5):439-443
The vitamin D status of a general adult urban population was estimated between November and April in 1569 subjects selected
from 20 French cities grouped in nine geographical regions (between latitude 43° and 51° N). Major differences in 25-hydroxyvitamin
D (25(OH)D) concentration were found between regions, the lowest values being seen in the North and the greatest in the South,
with a significant ‘sun’ effect (r = 0.72; p = 0.03) and latitude effect (r = -0.79; p = 0.01). In this healthy adult population, 14% of subjects exhibited 25(OH)D values ≤ 30 nmol/l (12 ng/ml), which represents
the lower limit (< 2 SD) for a normal adult population measured in winter with the same method (RIA Incstar). A significant
negative correlation was found between serum intact parathyroid hormone (iPTH) and serum 25(OH)D values (p < 0.01). Serum iPTH held a stable plateau level at 36 pg/ml as long as serum 25(OH)D values were higher than 78 nmol/l (31
ng/ml), but increased when the serum 25(OH)D value fell below this. When the 25(OH)D concentration became equal to or lower
than 11.3 nmol/l (4.6 ng/ml), the PTH values reached the upper limit of normal values (55 pg/ml) found in vitamin D replete
subjects. These results showed that in French normal adults living in an urban environment with a lack of direct exposure
to sunshine, diet failed to provide an adequate amount of vitamin D. It is important to pay attention to this rather high
prevalence of vitamin D insufficiency in the general adult population and to discuss the clinical utility of winter supplementation
with low doses of vitamin D. 相似文献