Fracture Prevention Program Research Articles

Vitamin D and vitamin D analogues for preventing fractures associated with involutional and post-menopausal osteoporosis.

Due to their known effects on bone metabolism, vitamin D and related compounds have been proposed for the prevention of osteoporosis and fractures. To determine the effects of supplementation with Vitamin D or a Vitamin D analogue in the prevention of fractures of the axial and appendicular skeleton in elderly men or women with involutional or post-menopausal osteoporosis. We searched MEDLINE, EMBASE, CINAHL, LILACS, CABNAR, BIOSIS, HEALTHSTAR, Current Contents, The Cochrane Database of Systematic Reviews, the Cochrane Musculoskeletal Injuries Group trials register, and bibliographies of identified trials and reviews. Date of the most recent search: September 2000. Any randomised or quasi-randomised trial which compared vitamin D or a vitamin D analogue, either alone or in combination with calcium supplementation, with a placebo, no intervention, or the administration of calcium supplements, with eligible fracture outcomes, in elderly men or women with involutional or post-menopausal osteoporosis. Two reviewers independently assessed trial quality, by use of a nine item scale, and extracted data. Additional information was sought from trialists. Where possible the data were pooled. Pooling of data, where it was admissible, used pooled relative risk and fixed effects model. Almost all estimates of treatment effects are based on single studies. Administration of vitamin D3 alone without calcium co-supplementation was not associated with any reduction in incidence of hip fracture (relative risk (RR) 1.20, 95% confidence interval (CI) 0.83, 1.75) or other non-vertebral fracture. Administration of vitamin D3 with calcium co-supplementation to frail elderly people in sheltered accommodation was associated with a reduction in incidence of hip fracture (RR 0.74, 95% CI 0.60, 0.91). In healthy younger, ambulant participants the effect on hip fracture is unknown (RR 0.36, 95% CI 0.01, 8.78), although there appears to be a significant overall effect on non-vertebral fracture incidence in this group ( RR 0.46, 95% CI 0.23,0.90). Calcitriol (1,25 dihdyroxy vitamin D) was effective in reducing the incidence of vertebral deformity (RR 0.49, 95% CI 0.25, 0.95). Calcitriol was more effective than calcium in reducing the frequency of new vertebral deformities during the third year of treatment (RR 0.28, 95% CI 0.15, 0.52). 1-alpha-hydroxy vitamin D was effective in reducing the incidence of non-vertebral fractures in a single small study of elderly people whose mobility was impaired by neurological disease (RR 0.12, 95% CI 0.02, 0.95). No statistically significant effects were found for other comparisons of vitamin D or its analogues against each other, with and without calcium supplementation. Uncertainty remains about the efficacy of regimens which include vitamin D or its analogues in fracture prevention. Particularly if co-supplementation of calcium is required, significant cost differences are likely to exist between regimens. Further large randomised trials are currently being conducted to clarify the effectiveness of community fracture prevention programmes employing vitamin D supplementation.

Non-trauma mortality in elderly women with low bone mineral density

9704 ambulatory women aged 65 years or older were prospectively studied to determine whether low bone mineral density (osteopenia) was associated with mortality. Bone mineral density was measured at entry to the study by single-photon absorptiometry. 299 women died during a mean of 2·8 years' follow-up. Osteopenia was associated with increased non-trauma mortality, probably because it is a marker for several other adverse factors. Each standard deviation decrease in proximal radius bone mineral density (0·104 g/cm2) was associated with a 1·19-fold increase in mortality (95% confidence interval 1·04-1·36), adjusted for age and duration of follow-up. Diminished bone mineral density at the proximal radius was strongly associated with deaths from stroke (relative risk=1·74; 95% Cl 1·2-2·70), an association that was not confounded by history of previous stroke, hypertension, postmenopausal use of oestrogen, thiazide diuretic treatment, diabetes mellitus, and smoking. Most deaths in women with low bone mineral density are unrelated to the occurrence of fractures—an observation that should be taken into account when estimating the need for and cost-effectiveness of bone-density screening and fracture prevention programmes.

PREDICTION OF OSTEOPOROTIC FRACTURES IN THE GENERAL POPULATION BY A FRACTURE RISK SCORE

The possibility of predicting the occurrence of fractures on the basis of risk factors for osteoporosis was evaluated between 1975 and 1986 in a follow-up study of 1,014 women aged 45-64 years from a Dutch population sample. During the 9-year period of follow-up, 16% of the women experienced one or more fractures. Of 12 historical and radiologic risk factors for osteoporosis which are considered important in the biomedical literature, none were found to be strong indicators of future fractures. Complete information on risk factors was available for 742 women. A fracture risk score was calculated for each person by combining the simultaneous influence of several risk factors in a multivariate analysis. The risk score discriminated relatively well between women with high and low risks of fractures. The risk ratio between the highest and the lowest risk score quintiles was 6.4 for all fractures and 7.0 for type I osteoporotic fractures (fractures of the vertebral bodies and distal forearm). However, if belonging to the highest quintile was considered as a screening test for fracture prediction, the sensitivity and specificity were poor: 0.37 and 0.84, respectively, for all fractures and 0.48 and 0.83, respectively, for type I osteoporotic fractures. These results indicate that it might not be efficient to use risk factor status to select women for fracture prevention programs.