AJM Theme Issue: GI and NutritionClinical research studyRandomized Controlled Trial of Calcium in Healthy Older Women
Section snippets
Methods
This is a randomized controlled trial in healthy postmenopausal women that is designed to assess the effects of calcium on bone density and fracture incidence over a period of 5 years. The methods have been described.13 Briefly, subjects were aged more than 55 years, not receiving therapy for osteoporosis or taking calcium supplements, and free of major ongoing disease. Serum creatinine was less than 2.3 mg/dL (0.2 mmol/L), and serum 25-hydroxyvitamin D was greater than 10 μg/L (25 nmol/L).
Subject Disposition and Adherence
Subject disposition is shown in Figure 1. Of the women entering the study, noncompletion was attributable to death in 63, illness in 103, and personal reasons in 50. Among those still taking trial medication at 5 years, tablet compliance was approximately 85% in both treatment groups in each 6-month period. When subjects who discontinued trial medication are included, compliance over the entire study was 58% in the placebo group and 55% in the calcium group (P = .13).
Bone Mineral Density
In the intention-to-treat
Discussion
This study confirms the beneficial effects of calcium supplementation on bone density in healthy older women. It shows that these benefits are present throughout the skeleton, that they are independent of age, and that they are present in individuals with both high and low dietary calcium intakes. These results provide confirmation of similar findings in a number of smaller studies, but the size of the present trial allows these conclusions to be reached with much greater certainty. In
Acknowledgments
The authors are grateful to Professors Tim Cundy and Andrew Grey for their comments on the article, to Dr. James Davidson for undertaking the bone turnover marker analyses, and to Mission Pharmacal, San Antonio, Tex, for supplying the calcium citrate tablets and placebo.
References (16)
- et al.
Long-term effects of calcium supplementation on bone loss and fractures in postmenopausal women- a randomized controlled trial
Am J Med
(1995) - et al.
A controlled trial of the effect of calcium supplementation on bone density in postmenopausal women
N Engl J Med
(1990) - et al.
Prevention of postmenopausal osteoporosisA comparative study of exercise, calcium supplementation, and hormone-replacement therapy
N Engl J Med
(1991) - et al.
Effect of calcium supplementation on bone loss in postmenopausal women
N Engl J Med
(1993) - et al.
Meta-analysis of calcium supplementation for the prevention of postmenopausal osteoporosis
Endocrine Rev
(2002) - et al.
Effects of calcium supplements on femoral bone mineral density and vertebral fracture rate in vitamin-D-replete elderly patients
Osteoporos Int
(1994) - et al.
Correcting calcium nutritional deficiency prevents spine fractures in elderly women
J Bone Mineral Res
(1996) - et al.
Vitamin D3 and calcium to prevent hip fractures in the elderly women
N Engl J Med
(1992)
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