Background Once-daily injections of parathyroid hormone or its amino-terminal fragments increase bone formation and bone mass without causing hypercalcemia, but their effects on fractures are unknown. Methods We randomly assigned 1637 postmenopausal women with prior vertebral fractures to receive 20 or 40 μg of parathyroid hormone (1-34) or placebo, administered subcutaneously by the women daily. We obtained vertebral radiographs at base line and at the end of the study (median duration of observation, 21 months) and performed serial measurements of bone mass by dual-energy x-ray absorptiometry. Results New vertebral fractures occurred in 14 percent of the women in the placebo group and in 5 percent and 4 percent, respectively, of the women in the 20-μg and 40-μg parathyroid hormone groups; the respective relative risks of fracture in the 20-μg and 40-μg groups, as compared with the placebo group, were 0.35 and 0.31 (95 percent confidence intervals, 0.22 to 0.55 and 0.19 to 0.50). New nonvertebral fragili...

Effect of parathyroid hormone (1-34) on fractures and bone mineral density in postmenopausal women with osteoporosis.

Background Inadequate dietary intake of calcium and vitamin D may contribute to the high prevalence of osteoporosis among older persons. Methods We studied the effects of three years of dietary supplementation with calcium and vitamin D on bone mineral density, biochemical measures of bone metabolism, and the incidence of nonvertebral fractures in 176 men and 213 women 65 years of age or older who were living at home. They received either 500 mg of calcium plus 700 IU of vitamin D3 (cholecalciferol) per day or placebo. Bone mineral density was measured by dual-energy x-ray absorptiometry, blood and urine were analyzed every six months, and cases of nonvertebral fracture were ascertained by means of interviews and verified with use of hospital records. Results The mean (±SD) changes in bone mineral density in the calcium–vitamin D and placebo groups were as follows: femoral neck, +0.50±4.80 and -0.70±5.03 percent, respectively (P = 0.02); spine, +2.12±4.06 and +1.22±4.25 percent (P = 0.04); and total body,...

Effect of Calcium and Vitamin D Supplementation on Bone Density in Men and Women 65 Years of Age or Older

See related commentary by Kanis, page [1829][1]

Since the publication of the Osteoporosis Canada guidelines in 2002, there has been a paradigm shift in the prevention and treatment of osteoporosis and fractures. [1][2],[2][3] The focus now is on preventing fragility fractures and their negative

/pdf/2010-clinical-practice-guidelines-for-the-diagnosis-and-4ttqfkm9wl.pdf

2010 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada: summary

https://www.stayonyourfeet.com.au/wp-content/uploads/2015/03/Tang-Calcium-Supplementation-2007.pdf

Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis

Objective: The purpose of this review is to provide guidance on the development, validation and use of food-frequency questionnaires (FFQs) for different study designs. It does not include any recommendations about the most appropriate method for dietary assessment (e.g. food-frequency questionnaire versus weighed record). Methods: A comprehensive search of electronic databases was carried out for publications from 1980 to 1999. Findings from the review were then commented upon and added to by a group of international experts. Results: Recommendations have been developed to aid in the design, validation and use of FFQs. Specific details of each of these areas are discussed in the text. Conclusions: FFQs are being used in a variety of ways and different study designs. There is no gold standard for directly assessing the validity of FFQs. Nevertheless, the outcome of this review should help those wishing to develop or adapt an FFQ to validate it for its intended use.

/pdf/development-validation-and-utilisation-of-food-frequency-148skc2jci.pdf

Development, validation and utilisation of food-frequency questionnaires - a review.

Background The use of calcium supplements slows bone loss in the forearm and has a beneficial effect on the axial bone density of women in late menopause whose calcium intake is less than 400 mg per day. However, the effect of a calcium supplement of 1000 mg per day on the axial bone density of postmenopausal women with higher calcium intakes is not known. Methods We studied 122 normal women at least three years after they had reached menopause who had a mean dietary calcium intake of 750 mg per day. The women were randomly assigned to treatment with either calcium (1000 mg per day) or placebo for two years. The bone mineral density of the total body, lumbar spine, and proximal femur was measured every six months by dual-energy x-ray absorptiometry. Serum and urine indexes of calcium metabolism were measured at base line and after 3, 12, and 24 months. Results The mean (±SE) rate of loss of total-body bone mineral density was reduced by 43 percent in the calcium group (-0.0055 ±0.0010 g per square centime...

https://www.nejm.org/doi/pdf/10.1056/NEJM199302183280702

Effect of calcium supplementation on bone loss in postmenopausal women

In order to determine which clinical, anthropometric, dietary, and biochemical variables are independent predictors of total and regional bone mineral density (BMD) in normal postmenopausal women, a cross-sectional study of 140 normal postmenopausal women has been carried out. Subjects were white, aged 45-71 yr (mean 58 yr), and had no history of disorders or medication use likely to influence bone or calcium metabolism. Multiple regression analysis was used to derive models for total and regional BMD in terms of the other variables measured. The analysis indicated that total body BMD was positively related to fat mass (P less than 0.0001), serum estrone (P = 0.0095) and age at menopause (P = 0.0165), and negatively related to age (P less than 0.0001), 24-h urine calcium (P = 0.0002), sex hormone-binding globulin (P = 0.0003), and serum alkaline phosphatase activity (P = 0.0029) (R2 = 0.61). Similar relationships were found in the subregions of the total body scans and in the lumbar spine and proximal femur, with insulin-like growth factor-1, parity, and age at menarche also being related to BMD at at least two of these sites. Lean body mass was not an independent correlate of BMD at any site once fat mass was taken into account. Muscle strength, physical activity, alcohol intake, and dietary intakes of calcium, sodium and protein did not emerge as significant predictors of BMD in this homogeneous group of postmenopausal women. We conclude that total body fat is the most significant predictor of BMD throughout the skeleton and this relationship is not explicable in terms of either estrone production in fat tissue or the dependence of skeletal load-bearing on fat mass. The mechanism underlying this relationship is an important question to be addressed in bone biology.

Determinants of total body and regional bone mineral density in normal postmenopausal women--a key role for fat mass.

Long-term effects of calcium supplementation on bone loss and fractures in postmenopausal women: a randomized controlled trial.

Determinants of Total Body and Regional Bone Mineral Density in Normal Postmenopausal Women—A Key Role for Fat Mass

Despite a large number of studies assessing relationships between putative risk factors and bone density, it is not known which factors influence the rate of axial bone loss in normal postmenopausal women. We have examined the relationships between the rate of bone loss (delta BMD) and variables related to calcium metabolism, lifestyle, diet (calcium, sodium, caffeine, and protein), body composition, muscle strength, sex hormones, and spinal osteophytosis in 122 normal postmenopausal women participating in a 2-yr prospective randomized placebo-controlled trial of calcium supplementation. Univariate correlation coefficients indicated that delta BMD at most sites was inversely related to baseline BMD and positively related to rate of change in body weight (0.10 < r < 0.36) and fat mass (0.11 < r < 0.42) during the study. Lean mass and its rate of change showed no consistent relationship to delta BMD. There was no correlation between delta BMD and any of the lifestyle, muscle strength, dietary, or hormonal indices or with the severity of spinal osteophytosis. Multiple regression analysis indicated that delta BMD in the total body was directly related to fat mass (P < 0.0001), the rate of change in fat mass (P < 0.0001), the renal tubular reabsorption of calcium (P < 0.01), and calcium treatment (P < 0.01) and inversely to the initial BMD (P < 0.0001; r2 = 0.42; P < 0.0001). Similar effects were seen throughout the skeleton, although the fraction of the variance accounted for was less in the subregions, consistent with the lower precision of measurement of regional bone density. It is concluded that baseline bone density, fat mass, and renal calcium handling are important factors influencing bone loss in normal postmenopausal women.

Susan J. Sharpe

Papers

Effect of calcium supplementation on bone loss in postmenopausal women

Determinants of total body and regional bone mineral density in normal postmenopausal women--a key role for fat mass.

Long-term effects of calcium supplementation on bone loss and fractures in postmenopausal women: a randomized controlled trial.

Determinants of Total Body and Regional Bone Mineral Density in Normal Postmenopausal Women—A Key Role for Fat Mass

Determinants of the rate of bone loss in normal postmenopausal women.