Effect of alendronate and vitamin D3 on fractional calcium absorption in a double-blind, randomized, placebo-controlled trial in postmenopausal osteoporotic women.
J Bone Miner Res
; 26(8): 1836-44, 2011 Aug.
Article
en En
| MEDLINE
| ID: mdl-21448918
ABSTRACT
Menopause and increasing age are associated with a decrease in calcium absorption that can contribute to the pathogenesis of osteoporosis. We hypothesized that alendronate plus vitamin D(3) (ALN + D) would increase fractional calcium absorption (FCA). In this randomized, double-blind, placebo-controlled multicenter clinical trial, 56 postmenopausal women with 25-hydroxyvitamin D [25(OH)D] concentrations of 25 ng/mL or less and low bone mineral density (BMD) received 5 weekly doses of placebo or alendronate 70 mg plus vitamin D(3) 2800 IU (ALN + D). Calcium intake was stabilized to approximately 1200 mg/d prior to randomization. FCA was determined using a dual-tracer stable-calcium isotope method. FCA and 25(OH)D were similar between treatment groups at baseline (0.31 ± 0.12 ng/mL and 19.8 ± 4.7 ng/mL, respectively). After 1 month of treatment, subjects randomized to ALN + D experienced a significant least squares (LS) mean [95% confidence interval (CI)] increase in FCA [0.070 (0.042, 0.098)], whereas FCA did not change significantly in the placebo group [-0.016 (-0.044, 0.012)]. After ALN + D treatment, patients had higher 25(OH)D levels (LS mean difference 7.3 ng/mL, p < .001). The rise in serum 1,25-dihydroxyvitamin D(3) (p < .02) and parathyroid hormone (p < .001) were greater in the ALN + D group than in placebo-treated patients. ALN + D was associated with an increase in FCA of 0.07. To our knowledge, there is no other trial showing such a marked rise in calcium absorption owing to treatment with a bisphosphonate or owing to a small rise in 25(OH)D. This unique response of ALN + D is important for the treatment of osteoporosis, but the exact mechanism requires further study.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Osteoporosis Posmenopáusica
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Calcio
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Colecalciferol
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Alendronato
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Conservadores de la Densidad Ósea
Tipo de estudio:
Clinical_trials
Límite:
Aged
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Aged80
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Female
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Humans
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Middle aged
Idioma:
En
Revista:
J Bone Miner Res
Asunto de la revista:
METABOLISMO
/
ORTOPEDIA
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos