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1.
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
2.
A. L. Haagensen H. A. Feldman J. Ringelheim C. M. Gordon 《Osteoporosis international》2008,19(3):289-294
Summary Fifty adolescents with AN and 200 healthy girls underwent vitamin D screening. Girls with AN reported exceptional compliance
with vitamin D supplementation and PTH concentrations were lower. Vitamin D deficiency was less common in the group with AN,
but when race was considered, the trend was no longer significant.
Introduction The objective of this study was to determine whether patients with anorexia nervosa (AN) are more compliant with supplementation
and have a lower prevalence of vitamin D deficiency than healthy controls.
Methods Fifty adolescents with AN and 200 controls were compared using anthropometric and lifestyle data, serum 25-hydroxyvitamin
D (25OHD) and parathyroid hormone (PTH) concentrations, and prevalence of vitamin D deficiency.
Results The prevalence of deficiency (<20 ng/mL) was 2% in the AN group vs. 24% among controls (p = 0.003). 25OHD was similar among white participants with AN and white controls (39.5 vs. 36.0 ng/mL, p = 0.20), but higher than in non-white controls (20.6 ng/mL). Significantly more girls with AN reported vitamin D supplementation
(86%) than the full control (14%) or white subgroup (27%) (p < 0.001). Participants with AN had lower PTH concentrations than controls, (27.8 vs. 47.4 pg/mL, p = 0.009), a trend that lost significance after age and race adjustment (41.7 pg/mL, p = 0.12).
Conclusions Compared to healthy controls, adolescents with AN had a lower prevalence of vitamin D deficiency and PTH concentration. However,
25OHD and PTH concentrations were similar after adjustment for race and age. The trend of lower PTH levels in adolescents
with AN, accompanied by exceptional compliance with supplementation, may have bone health implications for these patients.
Research Support: Funded by NIH Grants RO1 HD043869 and MO1-RR-2172 to the Children’s Hospital General Clinical Research Center;
Department of Defense (US Army, Bone Health and Military Readiness); and Project S-T71-MC-0000-10-S1-R0 from the Maternal
and Child Health Bureau. 相似文献
3.
D. M. Antoniucci E. Vittinghoff L. Palermo D. M. Black D. E. Sellmeyer 《Osteoporosis international》2009,20(7):1259-1266
Summary We investigated whether osteoporosis therapy with alendronate in postmenopausal patients is equally effective in patients
who are vitamin D insufficient as in those who are vitamin D sufficient. We found that vitamin D insufficiency is common among
patients with low bone density but that vitamin D insufficiency did not impair response to alendronate.
Introduction Treatment of vitamin D deficiency leads to significant improvements in bone mineral density (BMD); however, whether insufficiency
affects BMD’s response to bisphosphonate therapy is unknown.
Methods To determine whether vitamin D insufficiency at initiation of alendronate therapy for low BMD affects treatment efficacy,
we used data from 1,000 postmenopausal women randomly selected from the vertebral fracture arm (n = 2,027) of the placebo-controlled Fracture Intervention Trial of alendronate. Participants were randomly assigned to placebo
(50%) or alendronate therapy and most (83%) to calcium (500 mg/day) and cholecalciferol (250 IU/day). We measured serum 25-hydroxy
vitamin D (25OHD) at enrollment, then categorized baseline vitamin D status according to 25OHD concentration ( ≤ 10 ng/ml = deficient;
>10 but ≤ 30 ng/ml = insufficient; >30 ng/ml = sufficient) and used linear regression to compare the effects of alendronate
treatment among these categories.
Results and conclusion At baseline, participants were vitamin D sufficient (14%), insufficient (83%), and deficient (2%). We found that BMD response
to therapy at total hip or spine did not vary by vitamin D status at baseline (p for heterogeneity = 0.6). We determined that vitamin D insufficiency is common among participants with low BMD. However,
vitamin D status at initiation of therapy does not affect BMD’s response to alendronate, when it is coadministered with cholecalciferol
and calcium.
Scholar’s Grant from the National Osteoporosis Foundation (to D.M.A) and National Institutes of Health grant K23 RR020343
(to D.M.A). 相似文献
4.
Paul Glendenning Gerard T. Chew Hannah M. Seymour Melissa J. Gillett Peter R. Goldswain Charles A. Inderjeeth Samuel D. Vasikaran Mario Taranto Alexander A. Musk William D. Fraser 《BONE》2009,45(5):870-875
Vitamin D insufficiency is commonly associated with hip fracture. However, the equipotency of ergocalciferol and cholecalciferol supplementation in this patient group has not been studied in a randomized trial using high-performance liquid chromatography (HPLC) measurement of serum 25-hydroxyvitamin D (25OHD). The objective of this study was to determine if ergocalciferol and cholecalciferol are equipotent therapies in vitamin D-insufficient hip fracture patients.Ninety five hip fracture inpatients with vitamin D insufficiency (25OHD < 50 nmol/L) were randomized, double-blind, to treatment with ergocalciferol 1000 IU/day (n = 48) or cholecalciferol 1000 IU/day (n = 47) for three months. All participants were also given a placebo matching the alternative treatment to maintain blinding of treatment allocation. The primary endpoint was total serum 25OHD measured by HPLC. Secondary endpoints included 25OHD measured by radioimmunoassay (RIA), intact parathyroid hormone (iPTH), and bioactive (1–84) whole PTH (wPTH).Seventy patients (74%) completed the study with paired samples for analysis. Cholecalciferol supplementation resulted in a 31% greater increase in total HPLC-measured 25OHD (p = 0.010) and 52% greater rise in RIA-measured 25OHD (p < 0.001) than supplementation with an equivalent dose of ergocalciferol. Changes in iPTH and wPTH were not significantly different between calciferol treatments (p > 0.05).In vitamin D-insufficient hip fracture patients, supplementation with cholecalciferol 1000 IU/day for three months was more effective in increasing serum 25OHD than an equivalent dose of ergocalciferol. However, the lack of difference in PTH lowering between calciferol treatments raises questions about the biological importance of this observation. 相似文献
5.
Sanjeev Patel Jeffrey L. Barron Mehdi Mirzazedeh Hugh Gallagher Steve Hyer Tom Cantor William D. Fraser 《Journal of bone and mineral metabolism》2011,29(1):71-79
Vitamin D deficiency is associated with an increased risk of many diseases (skeletal and nonskeletal). Emerging data also
associate high concentrations of serum parathyroid hormone (PTH) with morbidity and increased mortality in patients both with
and without known chronic kidney disease (CKD). Understanding the relationship between vitamin D and PTH and the determinants
of PTH is therefore important. We performed a cross-sectional study of 203 patients with varying stages of CKD randomly recruited
from the Renal Unit database at our institution. Detailed case review was performed, and samples of fasting blood were taken
for biochemical analyses. We measured standard biochemistry, 25-hydroxyvitamin D (25-OHD), 1,25-OHD, and three PTH measurements
[1–84 PTH, total PTH, and derived N-terminal truncated, 7–84 PTH (cPTH)]. Vitamin D deficiency was high, with 86% of patients
having 25-OHD levels below 30 ng/ml. Estimated glomerular filtration rate (eGFR) was not associated with 25-OHD levels, whereas
1,25-OHD was lower in those with CKD stage 5 versus stage 4, who were not treated with vitamin D metabolites (18 vs. 65 pg/ml,
respectively; P < 0.05). All three PTH measurements increased with worsening eGFR, with this finding being more pronounced in those patients
who were not treated with vitamin D metabolites. The slope of the regression line of cPTH on eGFR tended to be steeper, –0.90,
compared to –0.81 for total PTH and –0.80 for 1–84 PTH (P = 0.06). The ratio of total PTH to cPTH did decrease significantly through the range of CKD stages (P = 0.03). The determinants of PTH were similar for all three PTH measurements, with eGFR having a strong inverse relationship,
with weaker relationships for 25-OHD and ionized calcium on multivariate analyses. We confirm that there is a complex relationship
between 25-OHD, eGFR, and PTH. Total PTH, 1–84 PTH, and cPTH increase with increasing CKD stages, with a relatively greater
increase in cPTH, although the clinical significance of this finding remains uncertain. The three PTH measurements had similar
correlations with the biochemical and clinical variables studied, suggesting that either total PTH or 1–84 PTH can be used
in clinical practice when evaluating vitamin D and PTH status. 相似文献
6.
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
7.
8.
N. Saquib D. von Mühlen C. F. Garland E. Barrett-Connor 《Osteoporosis international》2006,17(12):1734-1741
Introduction This study examined the distribution and determinants of serum 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) and their associations with bone mineral density (BMD) at the hip and spine in 414 older men (mean age 74 years) living in southern California.Methods At a clinic visit (1997–2000), demographic and lifestyle information, fracture history, and medication use were recorded; venous blood for serum 25OHD and PTH was obtained; and BMD was measured at the hip and spine.Results Only one man had vitamin D deficiency (25OHD <20 nmol/l), but 15.5% of the men had high parathyroid levels (PTH ≥65 pg/ml). The mean 25OHD and PTH levels were 109.0 nmol/l and 50.3 pg/ml, respectively. Overall, 21.5% used calcium and 9.7% used vitamin D supplements. Serum 25OHD decreased with age and was lowest in the winter; levels were higher in supplement users (vitamin D and/or calcium; p<0.01). Serum PTH did not vary by age or season, and it was lower in supplement users (p<0.01). After excluding 12 men who were outliers for serum 25OHD and PTH, there was no significant correlation between serum 25OHD and PTH (r=−0.05, p=0.3). In multiple adjusted models, serum 25OHD was positively associated with BMD at the hip (p=0.01) and spine (p=0.001). Serum PTH was moderately and inversely associated with BMD at the hip (p=0.04) but not at the spine (p=0.77).Conclusion We conclude that serum 25OHD is associated with bone health in older, community-dwelling men. 相似文献
9.
Shamir Tuchman Heidi J. Kalkwarf Babette S. Zemel Justine Shults Rachel J. Wetzsteon Debbie Foerster C. Frederic Strife Mary B. Leonard 《Pediatric nephrology (Berlin, Germany)》2010,25(12):2509-2516
The objectives were to determine the prevalence of vitamin D deficiency [25(OH)D < 10 ng/ml] in pediatric renal transplant
(RTx) recipients, compared with controls and identify correlates of changes in 25(OH)D and intact parathyroid hormone (iPTH)
levels following transplantation. Serum 25(OH)D, 1,25(OH)2D, and iPTH were measured once in 275 healthy controls and at transplantation, and 3 and 12 months posttransplantation in
58 RTx recipients. Multivariate logistic regression models determined the odds ratio (OR) of vitamin D deficiency in RTx recipients
vs. controls adjusted for age, sex, race, and season. Generalized estimating equations were used to assess changes following
transplantation. At transplantation, 22% of nonblack and 27% of black RTx recipients were vitamin D deficient. The adjusted
OR of vitamin D deficiency was greater in RTx recipients (p < 0.001) compared with controls; however, the transplant association was greater in nonblack vs. black individuals (interaction
p = 0.02). Overall, 25(OH)D levels did not change significantly following transplantation. Younger age (p < 0.01), nonblack race (p < 0.001), visits in nonwinter months (p < 0.001), and supplementation with ≥400 IU/day ergo/cholecalciferol (p < 0.001) were associated with increases (or lesser declines) in 25(OH)D following transplantation. Increases in 25(OH)D levels
(p < 0.001) and vitamin D supplementation (p < 0.01) were associated with greater reductions in iPTH levels following transplantation, independent of 1,25(OH)2D levels. 相似文献
10.
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
11.
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
12.
M. D. Walker I. Saeed J. A. Lee C. Zhang D. Hans T. Lang S. J. Silverberg 《Osteoporosis international》2016,27(10):3063-3071
Summary
Lower vitamin D and higher parathyroid hormone (PTH) levels are associated with higher volumetric BMD and bone strength at the lumbar spine as measured by central quantitative computed tomography in primary hyperparathyroidism (PHPT), but there are no differences in bone microarchitecture as measured by trabecular bone score (TBS).Introduction
The purpose of this study was to evaluate the association between 25-hydroxyvitamin D (25OHD) and volumetric bone mineral density (vBMD) and the TBS at the lumbar spine (LS) in PHPT.Methods
This is a cross-sectional analysis of PHPT patients with and without low 25OHD. We measured vBMD with quantitative computed tomography (cQCT) and TBS by dual-energy X-ray absorptiometry (DXA) at the LS in 52 and 88 participants, respectively.Results
In the cQCT cohort, those with lower vitamin D (<20 vs. 20-29 vs. ≥30 ng/ml) tended to be younger (p?=?0.05), were less likely to use vitamin D supplementation (p?<?0.01), and had better renal function (p?=?0.03). Those with 25OHD <20 ng/ml had 80 and 126 % higher serum PTH levels respectively vs. those with 25OHD 20–29 ng/ml (p?=?0.002) and 25OHD ≥30 ng/ml (p?<?0.0001). Covariate-adjusted integral and trabecular vBMD were higher in those with 25OHD 20–29 vs. those with 25OHD ≥30 ng/ml, but those with 25OHD <20 did not differ. Because there were few participants with 25OHD deficiency, we also compared those with vitamin D <30 vs. ≥30 ng/ml. Covariate-adjusted integral and trabecular vBMD were 23 and 30 % higher respectively (both p?<?0.05) in those with vitamin D <30 vs. ≥30 ng/ml. TBS was in the partially degraded range but did not differ by vitamin D status.Conclusion
In mild PHPT, lower 25OHD is associated with higher PTH, but vitamin D deficiency and insufficiency using current clinical thresholds did not adversely affect lumbar spine skeletal health in PHPT. Further work is needed to determine if higher vBMD in those with lower vitamin D is due to an anabolic effect of PTH.13.
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
14.
E. M. Keane M. Healy R. O'Moore D. Coakley J. B. Walsh 《Calcified tissue international》1998,62(4):300-302
To assess the efficacy and acceptability of vitamin D-fortified liquid milk in the management of hypovitaminosis D we carried
out a double-blind, randomized, controlled trial on 51 community-based, elderly subjects with serum 25 hydroxyvitamin D (25OHD)
levels of less than 12.9 ng/ml (normal range 10–80 ng/ml). Each subject had a dietary assessment, mental test score, outdoor
score, serum 25 hydroxyvitamin D level, and a general biochemical screening at baseline in April 1993 which was repeated in
September 1993, April 1994, and September 1994. All subjects received 500 ml of milk per day, delivered to their homes in
specially manufactured, blank, tetrapak cartons, from June 1993 to June 1994: 23 subjects received unfortified milk (control
group) and 28 subjects received fortified milk (active group). Our results showed a baseline mean 25OHD level in the active
group of 9.6 (range < 5.5–12.7) ng/ml and in the control group of 10.0 (range < 5.5–12.9) ng/ml (P < 0.4). One year later the mean 25OHD level in the active group had risen significantly from its baseline to 18.5 (range
9.6–26.7) ng/ml (P < 0.001) and was significantly different from the control group with a 1-year mean of 12.7 (range < 4–24.1) ng/ml (P < 0.001). Serum calcium levels in the active group also showed a significant rise over the 1-year period (P < 0.001) whereas those in the control group did not. We conclude that vitamin D-fortified liquid milk is a safe, effective,
and acceptable method of administering vitamin D to the elderly, community-based population.
Received: 31 January 1997 / Accepted: 17 June 1997 相似文献
15.
16.
High PTH levels increase bone turnover and decrease bone mineral density (BMD). Low plasma 25-hydroxyvitamin D (25OHD) levels
cause secondary hyperparathyroidism, but the relative contribution of low 25OHD and high PTH levels on risk of fracture is
largely unknown. Within the cohort of women (n = 2,016) included in the Danish Osteoporosis Prevention Study (DOPS), we studied risk of fracture according to parathyroid
status. Analyses were performed on effects of high PTH levels (i.e., in the upper tertile, ≥4.5 pmol/L) on risk of incident
fractures at different 25OHD levels during 16 years of follow-up. Incident fractures were assessed using a nationwide hospital
discharge register. In addition, effects of high PTH levels on BMD and vertebral fractures were assessed by DXA scans and
spinal X-ray examination after 10 years of follow-up. High PTH levels were associated with a decreased body mass index, adjusted
BMD, and an increased risk of any fracture (HR = 1.41, 95% CI 1.11–1.79) as well as an increased risk of osteoporotic fractures
(HR = 1.59, 95% CI 1.20–2.10). Plasma 25OHD levels per se did not affect fracture risk, but high PTH levels were associated
with an increased fracture risk only at 25OHD levels <50 nmol/L and 50–80 nmol/L. High PTH levels did not increase risk of
fracture at 25OHD levels >80 nmol/L. In conclusion, PTH levels in the upper part or above the upper level of the reference
interval increase risk of fracture in the presence of low vitamin D levels. 相似文献
17.
Lapatsanis D Moulas A Cholevas V Soukakos P Papadopoulou ZL Challa A 《Calcified tissue international》2005,77(6):348-355
Children and adolescents with the high bone turnover comprise a high risk population for vitamin D insufficiency. A sample
of 178 clinically healthy children aged 3 to 18 years who came from public schools and lived in North West of Greece participated
in the study. They were grouped into three age groups (I: 3–10, II: 11–14 and III: 15–18 years of age). Blood samples were
taken during winter and summer months for determining calciotropic hormones, calcium, phosphate and biochemical markers of
bone synthesis.
A high percentage (47%) of the subjects aged 15–18 years was found to have 25OHD <10 ng/ml in winter but much less (13–14%)
of the younger ages (13–14 years), while in the summer they were all >10 ng/ml. The prevalence was even higher in the girls
of the older group accompanied by lower Pi concentrations again in winter (win:1.19±0.03, sum:1.93±0.03 mmol/l, p < 0.001). The 24,25(OH)2D levels were changing in parallel to 25OHD, but again in the older subjects, during winter, they were by 2/3 lower than the
summer ones (0.73±0.10 vs. 2.41±0.20 ng/ml, p < 0.001). No significant differences were found between seasons and groups in the 1,25(OH)2D levels. The biochemical markers of bone synthesis, osteocalcin (OC) and total alkaline phosphatase (ALP), were found significantly
lower in the girls of the older group both in winter and summer respectively.Even in a sunny country like Greece the adolescents
living in an urban area are in high risk for vitamin D deficiency during winter. Supplementation with vitamin D of milk, of
popular beverages and perhaps some foods would be of help. 相似文献
18.
Carina Signori Kerstyn C. Zalesin Barry Franklin Wendy L. Miller Peter A. McCullough 《Obesity surgery》2010,20(7):949-952
Obesity as well as bariatric surgery may increase the risk for vitamin D deficiency. We retrospectively compared vitamin D
levels in obese patients (n = 123) prior to bariatric surgery and 1 year postoperatively. We also evaluated parathyroid hormone levels (PTH) 1 year after
surgery. A higher percentage of patients had baseline vitamin D deficiency (86%), defined as 25-hydroxy vitamin D <32 ng/mL,
compared with the 1-year (post-surgical) levels, (70%; p < 0.001). Body mass index (BMI) inversely correlated with vitamin D deficiency at baseline (r = −0.3, p = 0.06) and at the postoperative follow-up (r = −0.2, p = 0.013). One third of the postoperative population had secondary hyperparathyroidism, defined by a serum PTH level >62 pg/mL;
however, postoperative PTH and vitamin D levels were unrelated (r = −0.001, p = 0.994). Pre- and postoperative vitamin D levels were inversely correlated with BMI. Secondary hyperparathyroidism was observed
in 33% of patients postoperatively; however, this did not correlate with vitamin D. 相似文献
19.
Background Bone disease has been described in patients after surgical treatment for obesity, but few studies have dealt with the impact
of vertical banded gastroplasty on mineral metabolism. We have examined bone mineral metabolism in morbidly obese patients
before and after 3 months after vertical banded gastroplasty without vitamin D supplementation.
Methods Sixteen morbidly obese patients (14 women, 2 men) with a mean (±SD) age of 38 ± 9 years and a body mass index (BMI) of 47.1 ± 8.1 kg/m2 were studied. No vitamin D supplementation was given. Body weight, fat mass, calcium, 25OHD, iPTH, bone remodeling markers,
and leptin levels were measured at baseline and after weight loss.
Results Mean weight loss was 28 ± 11 kg; BMI and body fat mass decreased by 20 and 35%, respectively. Bone resorption markers and
albumin-corrected serum calcium increased after operation, whereas iPTH fell. Serum 25OHD levels rose. Leptin levels decreased.
Serum iPTH was positively correlated with weight, BMI, and fat mass before operation (p < 0.05), and its decline after weight reduction was negatively associated with the increase in bone resorption markers (p < 0.01). Leptin concentration was correlated with BMI and body fat mass (p < 0.05) both before and after surgery.
Conclusions Weight reduction obtained in morbidly obese subjects 3 months after vertical banded gastroplasty increases bone turnover markers
and decreases PTH secretion. Serum 25OHD levels rose. Therefore, no reasons for a metabolic bone disease related to hypovitaminosis
D were readily apparent. However, an increase in bone turnover, which is generally regarded as a potential risk factor for
osteoporosis, was observed. Further work is needed to clarify the importance of this turnover increase in the long run. 相似文献
20.
Judy Jin Thomas A. Stellato Peter T. Hallowell Margaret Schuster Kristen Graf Scott Wilhelm 《Journal of gastrointestinal surgery》2009,13(6):1052-1057
Introduction Vitamin D deficiency occurring after gastric bypass procedures can predispose patients to calcium and parathyroid hormone
(PTH) level abnormalities. The aim of the study is to identify preoperative patient risk factors for postoperative vitamin
D deficiency.
Methods We retrospectively reviewed patients who underwent Roux-en-Y gastric bypass procedures between 2005 and 2006. Patient demographics,
laboratory values of calcium, vitamin D, and PTH were followed at quarterly intervals for 1 year.
Results One hundred forty-five patients were included in the study. The mean age for the group was 44 years with an average body mass
index of 49.5 kg/m2. Eighty-six percent of patients were female and 23% was African–American. Forty-two percent of the patients had vitamin D
deficiency (<20 ng/mL) either preoperatively or at year 1. The mean calcium levels decreased from 9.39 to 9.16 mg/dL (p < 0.001) while the mean PTH levels increased from 25.7 to 43.9 ng/mL (p < 0.001). A logistic regression model recognized preoperative vitamin D levels, race, and bypass limb length to be the only
significant factors (p < 0.05) for postoperative vitamin D deficiency.
Conclusion It is important to recognize patients who are at risk for vitamin D deficiency before surgery so that early intervention could
be in place to minimize further postoperative deficiency.
This paper had been presented as a poster at the DDW meeting May 2008, San Diego, CA, USA. 相似文献