Most estimates of osteoporosis in older U.S. adults have been based on its occurrence in white women, even though it is known to affect men and minority women. In the present study, we used dual-energy X-ray absorptiometry measurements of femoral bone mineral density (BMD) from the third National Health and Nutrition Examination Survey (NHANES III, 1988–1994) to estimate the overall scope of the disease in the older U.S. population. Specifically, we estimate prevalences of low femoral BMD in women 50 years and older and explore different approaches for defining low BMD in older men in that age range. Low BMD levels were defined in accordance with an approach proposed by an expert panel of the World Health Organization and used BMD data from 382 non-Hispanic white (NHW) men or 409 NHW women ages 20–29 years from the NHANES III dataset. For women, estimates indicate 13–18%, or 4–6 million, have osteoporosis (i.e., BMD >2.5 standard deviations [SD] below the mean of young NHW women) and 37–50%, or 13–17 million, have osteopenia (BMD between 1 and 2.5 SD below the mean of young NHW women). For men, these numbers depend on the gender of the reference group used to define cutoff values. When based on male cutoffs, 3–6% (1–2 million) of men have osteoporosis and 28–47% (8–13 million) have osteopenia; when based on female cutoffs, 1–4% (280,000–1 million) have osteoporosis and 15–33% (4–9 million) have osteopenia. Most of the older U.S. adults with low femur BMD are women, but, regardless of which cutoffs are used, the number of men is substantial.
Despite its association with disability, death, and increased medical costs, osteoporosis in men has been relatively neglected as a subject of study. There have been no large, controlled trials of treatment in men. In a two-year double-blind trial, we studied the effect of 10 mg of alendronate or placebo, given daily, on bone mineral density in 241 men (age, 31 to 87 years; mean, 63) with osteoporosis. Approximately one third had low serum free testosterone concentrations at base line; the rest had normal concentrations. Men with other secondary causes of osteoporosis were excluded. All the men received calcium and vitamin D supplements. The main outcome measures were the percent changes in lumbar-spine, hip, and total-body bone mineral density. The men who received alendronate had a mean (±SE) increase in bone mineral density of 7.1±0.3 percent at the lumbar spine, 2.5±0.4 percent at the femoral neck, and 2.0±0.2 percent for the total body (P<0.001 for all comparisons with base line). In contrast, men who received placebo had an increase in lumbar-spine bone mineral density of 1.8±0.5 percent (P<0.001 for the comparison with base line) and no significant changes in femoral-neck or total-body bone mineral density. The increase in bone mineral density in the alendronate group was greater than that in the placebo group at all measurement sites (P<0.001). The incidence of vertebral fractures was lower in the alendronate group than in the placebo group (0.8 percent vs. 7.1 percent, P=0.02). Men in the placebo group had a 2.4-mm decrease in height, as compared with a decrease of 0.6 mm in the alendronate group (P=0.02). Alendronate was generally well tolerated. In men with osteoporosis, alendronate significantly increases spine, hip, and total-body bone mineral density and helps prevent vertebral fractures and decreases in height.
All therapies currently recommended for the management of osteoporosis act mainly to inhibit bone resorption and reduce bone remodeling. PTH and its analog, teriparatide [recombinant human PTH(1-34)], represent a new class of anabolic therapies for the treatment of severe osteoporosis, having the potential to improve skeletal microarchitecture. Significant reductions in both vertebral and appendicular fracture rates have been demonstrated in the phase III trial of teriparatide, involving elderly women with at least one prevalent vertebral fracture before the onset of therapy. However, there is as yet no evidence that the antifracture efficacy of PTH will be superior to the bisphosphonates, whereas cost-utility estimates suggest that teriparatide is significantly more expensive. Teriparatide should be considered as treatment for postmenopausal women and men with severe osteoporosis, as well as for patients with established glucocorticoid-induced osteoporosis who require long-term steroid treatment. Teriparatide should also be considered for the management of individuals at particularly high risk for fractures, including subjects who are younger than age 65 and who have particularly low bone mineral density measurements (T scores < or = 3.5). Teriparatide therapy is not recommended for more than 2 yr, based, in part, on the induction of osteosarcoma in a rat model of carcinogenicity. Total daily calcium intake from both supplements and dietary sources should be limited to 1500 mg together with adequate vitamin D intake (< or =1000 U/d). Monitoring of serum calcium may be safely limited to measurement after 1 month of treatment; mild hypercalcemia may be treated by withdrawing dietary calcium supplements, reducing the dosing frequency of PTH, or both. At present, concurrent therapy with antiresorptive therapy, particularly bisphosphonates, should be avoided, although sequential therapy with such agents may consolidate the beneficial effects upon the skeleton after PTH is discontinued.
1 May 2005 in The Journal of Clinical Endocrinology & Metabolism
The proportion of fractures that occur in women without osteoporosis has not been fully described, and the characteristics of nonosteoporotic women who fracture are not well understood. We measured total hip bone mineral density (BMD) and baseline characteristics including physical activity, falls, and strength for 8065 women aged 65 yr or older participating in the Study of Osteoporotic Fractures and then followed these women for hip fracture for up to 5 yr after BMD measurement. Among all participants, 17% had osteoporosis (total hip BMD T-score ≤ −2.5). Of the 243 women with incident hip fracture, 54% were not osteoporotic at start of follow-up. Nonosteoporotic women who fractured were less likely than osteoporotic women with fracture to have baseline characteristics associated with frailty. Nevertheless, among nonosteoporotic participants, several characteristics increased fracture risk, including advancing age, lack of exercise in the last year, reduced visual contrast sensitivity, falls in the last year, prevalent vertebral fracture, and lower total hip BMD. These findings call attention to the many older women who suffer hip fracture but do not have particularly low antecedent BMD measures and help begin to identify risk factors associated with higher bone density levels.