Article type
Year
Abstract
Introduction: The risk of osteoporosis increases with age and is higher in women than in men. Osteoporosis among older women is a major health problem. The high prevalence of bone fractures among women with osteoporosis makes prevention of this disease important.
Objective: The purpose of this systematic review is to determine the effectiveness of calcium supplementation on bone loss in postmenopausal women. It is thought that the use of calcium supplementation slows bone loss and has a beneficial effect on the axial bone density of women, thus preventing hip fractures.
Methods: Using the Cochrane Collaboration Toolkit, all randomized control trials (RCTs) in which treatment with calcium supplementation was compared to control in postmenopausal women, were sought. The daily calcium doses included ranges from 400 mg to 2000 mg. The primary outcome was bone mineral density; other outcomes included the number of fractures on X-ray of the hip, vertebrae and wrist. A Medline computer search was carried out from 1966-1994, using the keywords "calcium", "osteoporosis", and "bone mass". Reference lists were reviewed and experts in the area were contacted to retrieve missing trials and unpublished data. This process is now ongoing.
Results: Thirteen RCTs were identified using search strategies outlined by Dickersin et al. Significant heterogeneity exists among trial results for bone density and fractures. There appears to be no relationship between the quality of the trials and the results assessed. Results vary by area of bone measurement and method of measurement. In particular, for the studies evaluating the femoral neck, a weighted mean difference of the BMD was only 0.39 and the corresponding 95% CI was (-0.46 - 1.24). With the addition of trials combining other interventions, such as exercise, there is more of a positive effect of calcium on bone mineral density.
Discussion: Despite the present theory that calcium supplementation does have an effect on bone mineral loss in postmenopausal women, the results of this meta-analysis do not support this theory.
Objective: The purpose of this systematic review is to determine the effectiveness of calcium supplementation on bone loss in postmenopausal women. It is thought that the use of calcium supplementation slows bone loss and has a beneficial effect on the axial bone density of women, thus preventing hip fractures.
Methods: Using the Cochrane Collaboration Toolkit, all randomized control trials (RCTs) in which treatment with calcium supplementation was compared to control in postmenopausal women, were sought. The daily calcium doses included ranges from 400 mg to 2000 mg. The primary outcome was bone mineral density; other outcomes included the number of fractures on X-ray of the hip, vertebrae and wrist. A Medline computer search was carried out from 1966-1994, using the keywords "calcium", "osteoporosis", and "bone mass". Reference lists were reviewed and experts in the area were contacted to retrieve missing trials and unpublished data. This process is now ongoing.
Results: Thirteen RCTs were identified using search strategies outlined by Dickersin et al. Significant heterogeneity exists among trial results for bone density and fractures. There appears to be no relationship between the quality of the trials and the results assessed. Results vary by area of bone measurement and method of measurement. In particular, for the studies evaluating the femoral neck, a weighted mean difference of the BMD was only 0.39 and the corresponding 95% CI was (-0.46 - 1.24). With the addition of trials combining other interventions, such as exercise, there is more of a positive effect of calcium on bone mineral density.
Discussion: Despite the present theory that calcium supplementation does have an effect on bone mineral loss in postmenopausal women, the results of this meta-analysis do not support this theory.