Prevalence Of Osteoporotic Fractures Research Articles

Transforming growth factor-beta1 gene polymorphism, bone turnover, and bone mass in Italian postmenopausal women.

Transforming growth factor beta1 (TGF-beta1) is abundant in bone and is an important regulator of the osteoclastic-osteoblastic interaction (coupling). The sequence variation, 713-8delC in the TGF-beta1 gene has previously been found to be associated with very low bone mass in osteoporotic women and with increased bone turnover in both osteoporotic and normal women. The possible association of this polymorphism with bone mass and bone turnover has now been investigated in 256 postmenopausal Italian women. A significant association of TGF-beta1 with bone mass was detected in the populations. Subjects carrying the sequence variation 713-8delC (Tt) genotype showed a significantly lower bone mineral density (BMD) at the hip than those without sequence variation in the genotype (TT). Individuals carrying the tt genotype have a more severe osteoporosis (P=0.0001 vs. TT and Tt genotypes). The frequency of the fragility fractures was significantly lower in individuals with TT genotype than in those with the Tt and tt genotypes (X2=21.9; P=0.006). Furthermore a significant association was found between 713-8delC and bone turnover. The results suggest a strong evidence for an association among the 713-8delC allele of the TGF-beta1 gene and the femoral BMD, the prevalence of osteoporotic fractures, and finally a high bone turnover in a sample of Italian postmenopausal women.

Bone mineral density in older non-Hispanic Caucasian and Mexican-American women: relationship to lean and fat mass

Primary objective: The prevalence of osteoporotic fracture is higher in non-Hispanic Caucasian (NHC) than Mexican-American (MA) women in the USA. The present study examined bone mineral density (BMD) in these two ethnic groups and the association between BMD and body composition.Research design: Cross-sectional.Subjects: Sixty-two NHC and 54 MA women, aged 60-86 years, with a body mass index (kgm-2) of < 30.Methods: BMD (gcm-2) of the spine (L2-4), hip (femoral neck, trochanter, Ward's triangle) and whole body was determined by dual-energy X-ray absorptiometry (DXA). Bone mineral-free lean mass (LM) and fat mass (FM) and several ratios of body fat distribution were also assessed by DXA.Results: There was no difference in age (NHC, 69.5 ± 0.7; MA 69.5 ± 0.9 years; mean ± SEM) or body mass, but MA women were shorter with a higher truncal adiposity (p < 0.001). There was no significant difference in BMD between groups, however, adjusting for height resulted in higher hip and whole body BMD in MA women (p < 0.01). When volumetric bone density was calculated (bone mineral apparent density; BMAD, g cm−3), a trend for higher values in MA women was observed at the femoral neck (p = 0.018). LM contributed independently to BMD at the spine and hip in NHC women, with FM also contributing at the femoral neck. In MA women, LM was an independent contributor to lumbar spine and trochanter BMD, and both LM and FM contributed to whole body BMD. However, the effects of LM and FM were removed in both groups when BMD was adjusted for body or bone size, the only exception being at the trochanter in NHC women.Conclusions: These results indicate that MA women have higher bone density at the proximalfemur than NHC women, which may partially account for their lower rate of hipfracture. Further, differences in bone density between the two ethnic groups do not appear to be dependent on soft-tissue composition.

Vertebral deformity as an index of osteoporosis-induced spinal fracture--an external validity construct based on bone density data

In order to test the validity of vertebral morphometry for the assessment of prevalent vertebral osteoporotic fractures, we examined the association between vertebral deformities and bone mineral density (BMD). The study population consisted of 595 postmenopausal women and 581 men aged 50 to 82 years who participated in the baseline survey of the European Vertebral Osteoporosis Study (EVOS) in Germany and received BMD measurements by dual-X-ray-absorptiometry (DXA) at the femur and the lumbar spine. In both sexes only vertebral deformities defined by more stringent morphometric criteria (McCloskey; Eastell 4 SD criterion) were significantly and inversely related to BMD (odds ratios 1.42 to 3.21 for a 1 SD [standard deviation] reduction in BMD; p < 0.05). The strength of the association depended on the stringency of the morphometric algorithm applied, and on the site of BMD measurement. The strongest associations were observed with femoral neck BMD in women and with BMD at the lumbar spine in men. In contingency analyses between vertebral deformities and osteoporosis (WHO criteria; European young female BMD reference values), vertebral deformities proved to be highly specific by all methods, even slightly more so in men (87.8 to 97.5%) than in women (86.3 to 96.7%). The predictive value of a positive test with respect to vertebral osteoporosis reached a maximum value of about 50% in both sexes. It further increased up to 72%, when the definition of osteoporosis was based on low BMD values at either the spine or the femoral neck, but only in women. In conclusion, for both men and women the likelihood of vertebral deformities to be related to osteoporosis increases with the stringency of the morphometric method, with a similar probability of major deformities to represent vertebral osteoporotic fractures in men as in women. Nevertheless, even the most stringent morphometric criteria are not sufficiently valid instruments for the assessment of the prevalence of vertebral osteoporotic fractures in epidemiological studies.

Bone quantity and quality in past populations.

The study of osteoporosis in past populations offers valuable insight into the patterns and prevalence of the disease in both the past and in the present. A review is made of different paleopathological studies better to understand bone loss in past populations and to examine the contribution such studies can make to our knowledge of osteoporosis in modern populations. The review includes studies of bone mass in past populations from different geographic regions. Nutritionally based hypotheses, traditionally used to explain bone loss in past populations, are reviewed and assessed against the current clinical and epidemiological findings. In general, the various studies have revealed different degrees of low bone mass in past populations; however, the pattern of bone loss and fragility seen in age-related and postmenopausal osteoporosis today is not evident in the past. Bone loss in earlier populations is often found in both sexes, whereas significant bone loss in females occurs often among the young-age categories. In addition, a prevalence of osteoporotic fracture is absent. We suggest that, despite influences that may have reduced bone mass in past populations, a protection of bone quality may have occurred, reducing the likelihood of bone fragility and fracture typically seen in modern osteoporotics. It seems evident that, although reduced bone mass may be prevalent in past history, clinically recognized osteoporosis is not.

Non-dental tissue effects of fluoride.

The anti-caries effects of water fluoridation are well-established. The non-dental tissue effects of fluoride in drinking water, either naturally occurring or as an additive, have been too poorly studied to permit definitive conclusions to be drawn. Claims have been made that fluoride results in an increased occurrence of malignancies, particularly osteogenic sarcoma. Experimental rat data have not resolved this issue, and epidemiologic studies are equally unclear. Initial claims that fluoride offers protection against atherosclerosis remain viable, but here too, much more directed research is needed. Early studies suggested that a water fluoride content greater than 1 ppm resulted in a lower prevalence of osteoporotic fractures. Recent epidemiologic data seriously question this conclusion and raise the possibility that even this relatively low level may increase the prevalence of osteoporotic hip fractures. Other elements, including calcium and magnesium, also vary in amount as water fluoride content varies, and it has proved difficult to distinguish the independent effects of the various nutrients in water from each other. Therapeutic use of fluoride has been largely restricted to studies of its effect on the osteoporotic study, this important issue remains unresolved. This review provides an overview of these issues, focusing on the uncertainties alluded to, and attempting to develop strategies for future research.

Skeletal osteoporosis.

Osteoporosis is characterized by decreased bone mass and increased susceptibility to fractures. The clinical consequences of osteoporosis are fracture, most commonly seen at the wrist, the spine, and the hip. The prevalence of osteoporotic fracture is extremely high with 30%-40% of 70-year-old women having had at least one osteoporotic fracture. The prevalence in men is lower but may constitute a larger problem than expected. Osteoporotic fracture is, therefore, a significant cause of morbidity and mortality and represents a major problem of health care. Bone is the site of substantial metabolic exchanges, with bone resorption and formation continuing throughout life. The turnover processes are carried out by osteoclasts and osteoblasts in specialized cellular units. After cessation of growth, the skeleton probably consolidates to reach the peak bone mass at the age of 35-40 years. The relatively slow subsequent age-related bone loss occurs in both men and women, but women are additionally exposed to accelerated bone losses after the menopause. Estrogen deficiency is the dominating pathogenetic factor for osteoporosis in women. The role of disturbances in the calcium-regulating hormones and vitamin D deficiency is less sure. The pathophysiologic mechanisms of osteoporosis in men are not well investigated. Those who are endowed with a low peak bone mass and/or are exposed to a large bone loss are at particular risk of developing symptomatic osteoporosis. Several risk factors have been recognized but are insufficiently sensitive and specific to predict an individual's overall risk of developing osteoporosis.

Beliefs About Osteoporosis

The awareness of osteoporosis as a common problem with a large degree of associated morbidity has increased recently. In this article, three beliefs concerning osteoporosis are examined. These beliefs concern the usefulness of radiologic screening for osteoporosis, the prevalence of osteoporotic fractures, and the benefit of calcium supplementation. It is concluded that as a widely used screening test, radiologic examination does not greatly aid in the estimation of risk of future bone fracture; that fewer than one fourth of women will ever have a meaningful complication from excessive bone loss; and that, although low calcium intake is probably inadvisable, the present data do not allow us to recommend any certain level of calcium intake as being optimal.