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S. Adami – One of the best experts on this subject based on the ideXlab platform.
Osteoporosis International, 1994Co-Authors: S. AdamiAbstract:
Bone Mass in the elderly depends on the rate of involutional Bone loss and on the peak Bone Mass, i.e. the Bone Mass present around the third decade of life. Factors relating to the attainment of peak Bone Mass include congenital factors, diet, hormones, physical activity, lifestyle factors, drags and diseases. A therapeutic intervention aimed at increasing peak Bone Mass is conceivable only by controlling factors such as estrogen status, dietary calcium intake and physical activity. Calcium intake appears to be relevant up to the so-called threshold intake (1000 mg/day), but higher allowances do not seem to offer additive advantages. Exercise affects only the regions of the skeleton under mechanical stress. Estrogen administration is realistic only in conditions characterized by severe hypoestrogenism.
R D Wasnich – One of the best experts on this subject based on the ideXlab platform.
The American journal of medicine, 1993Co-Authors: R D WasnichAbstract:
Accurate assessment of individual fracture risk requires measurement of Bone Mass (density). Another strong risk factor for identifying women or men who will develop fractures in the near future is the presence of previous (spine and nonspine) fractures. However, the occurrence of a low-trauma fracture almost anywhere in the skeleton is indicative of a more advanced stage of disease and is associated with a substantial, further increase in fracture risk, independent of Bone Mass. Thus, prevention of the first fracture should receive priority. In a clinical setting, initial assessment of Bone Mass can be combined with other, known risk factors and projected over the patient’s remaining life expectancy, to estimate future, cumulative fracture probability. Estimates such as “remaining lifetime fracture probability” can also approximate the impact and cost-effectiveness of treatment, allowing for more objective and rational therapeutic planning for individual patients.
Calcified tissue international, 1993Co-Authors: P D Ross, J W Davis, R D WasnichAbstract:
Numerous prospective studies have demonstrated a strong relationship between Bone Mass and fracture risk. The fact that the Bone Mass distributions of fracture and nonfracture cases overlap does not necessarily indicate a shortcoming of Bone Mass, but might instead be due to the sporadic nature of falls and the influence of other fracture risk factors. The recent finding that prevalent fractures are strong predictors of fracture risk, independent of Bone Mass, suggests (but does not prove) that there may be other, potentially measurable fracture risk factors that complement, and act independently of, Bone Mass. This paper reviews possible mechanisms by which prevalent fractures might serve as etiologic risk factors, or as surrogate indicators of other risk factors. Potential risk factors other than Bone Mass and prevalent fractures are also considered. Whether or not etiologic fracture risk factors other than Bone Mass can be identified, it appears that treatments that influence Bone will be most effective if begun early, before Bone strength becomes impaired and fractures begin to occur.
Bone, 1992Co-Authors: P D Ross, James Davis, C.j. Maclean, Robert S. Epstein, R D WasnichAbstract:
Abstract The development of statistical models for estimating fracture probability is a promising method for quantitating and optimizing the clinical utility of Bone Mass measurements. Earlier models have assumed that future Bone Mass could be predicted exactly and were, therefore, limited to analyses that assume the loss rate is known in advance. Since Bone loss rates may vary over time and cannot be predicted accurately, we have developed a new model, based on empirical data, that estimates the degree of uncertainty associated with predicted Bone Mass. Without a Bone Mass measurement, the population mean must be assumed for an individual. For the calcaneus, the standard deviation of the population distribution is about 60 mg/cm2. By measuring Bone Mass, one can determine how close or far from the mean an individual’s true Bone Mass is, with a standard deviation (SD) of about 3 mg/cm2. Without a subsequent Bone Mass measurement, our model predicts that the uncertainty (standard deviation) in calcaneal Bone Mass will increase approximately sixfold (relative to the reproducibility at the initial measurement) over a period of five years for women under age 60, from 3 mg/cm2 to 19 mg/cm2. The five-year increase in uncertainty is approximately fourfold for women over age 60, from 3 to 13 mg/cm2. However, the uncertainty in Bone Mass for an individual five years after the initial measurement is still only one third to one fifth that of the entire population, and can be reduced to the initial level by obtaining another measurement. Furthermore, the predicted (or measured) values are usually much better estimates of an individual’s true Bone Mass than simply assuming the population average. This model can be adapted to other types of Bone Mass measurements, and will find application in cost-effectiveness analyses of osteoporosis treatment and prophylaxis, including estimation of the optimal time interval between Bone Mass measurements.
Jane A. Cauley – One of the best experts on this subject based on the ideXlab platform.
Relationship between Bone Mass, invasive breast cancer incidence and raloxifene therapy in postmenopausal women with low Bone Mass or osteoporosis.Current medical research and opinion, 2008Co-Authors: Alan L. Burshell, Jing Li Song, Sherie A. Dowsett, John L. Mershon, Pierre D. Delmas, Roberta J. Secrest, Jane A. CauleyAbstract:
ABSTRACTObjective: To evaluate the relationship between Bone Mass and risk of breast cancer and to determine the effect of raloxifene therapy on breast cancer incidence in women categorized by Bone Mass into low Bone Mass and osteoporosis subgroups.Design: In this post hoc analysis, data were analyzed from the Multiple Outcomes of Raloxifene Evaluation (MORE) trial, enrolling postmenopausal women with low Bone Mass (N = 7705), and the Continuing Outcomes Relevant to Evista (CORE) trial, a follow-up to MORE enrolling 4011 MORE participants. Total follow-up was for up to 8 years. Women with a total hip Bone mineral density (BMD) T-score –2.5 or T-score ≤ –2.5 (referent, NHANES III database) were classified as having low Bone Mass or osteoporosis, respectively. Women with a pre-existing vertebral fracture were considered as having osteoporosis irrespective of BMD T-score. Analyses were performed for invasive breast cancers and invasive estrogen-receptor (ER) positive breast cancers.Results: Women …
Annals of Internal Medicine, 1993Co-Authors: Jane A. Cauley, Steven R Cummings, Dana G Seeley, Dennis Black, Warren S Browner, Lewis H. Kuller, Michael C NevittAbstract:
René Rizzoli – One of the best experts on this subject based on the ideXlab platform.
Nutritional Aspects of Osteoporosis, 1998Co-Authors: S. Ferrari, René Rizzoli, Jean-philippe BonjourAbstract:
Postmenopausal and age-related Bone losses have long been recognized as major determinants of the risk for osteoporotic fractures. More recently, the importance of optimizing peak Bone Mass, which is achieved by the end of puberty (1, 2), to prevent the detrimental effects of later Bone loss has been emphasized (3). A number of issues, however, are unclear in this regard, such as knowing to what extent the attainment of peak Bone Mass can be modified by external factors. Indeed, peak Bone Mass appears to be under strong genetic determination (4). Similarly, it is still not firmly established when during the course of skeletal growth these genetic factors are intervening or how much of the apparent heritability for Bone Mass is truly attributable to genetic effects. On the other hand, prospective studies showing significant alterations of the spontaneous Bone Mass growth through dietary or life-style interventions are rather limited. Besides, there are no available data concerning the potential influence of genetics—environment interactions on Bone Mass accrual during growth.
Osteoporosis International, 1994Co-Authors: Jean-philippe Bonjour, G Theintz, F Law, D. Slosman, René RizzoliAbstract:
Peak Bone Mass, which can be defined as the amount of bony tissue present at the end of the skeletal maturation, is an important determinant of osteoporotic fracture risk.Measurement of Bone Mass development. The Bone Mass of a given part of the skeleton is directly dependent upon both its volume or size and the density of the mineralized tissue contained within the periosteal envelope. The techniques of single-1 and dual-energy photon or X-ray absorptiometry measure the so-called ‘areal’ or ‘surface’ Bone mineral density (BMD), a variable which has been shown to be directly related to Bone strength.Bone Mass gain during puberty. During puberty the gender difference in Bone Mass becomes expressed. This difference appears to be essentially due to a more prolonged Bone maturation period in males than in females, with a larger increase in Bone size and cortical thickness. Puberty affects Bone size much more than the volumetric mineral density. There is no significant sex difference in the volumetric trabecular density at the end of pubertal maturation. During puberty, the accumulation rate in areal BMD at both the lumbar spine and femoral neck levels increases to four- to sixfold over a 3-and 4-year period in females and males, respectively. Change in Bone Mass accumulation rate is less marked in long Bone diaphyses. There is an asynchrony between the gain in statural height and Bone Mass growth. This phenomenon may be responsible for the occurrence of a transient period of a relative increase in Bone fragility that may account for the pattern of fracture incidence during adolescence.Variance in peak Bone Mass. At the beginning of the third decade there is a large variability in the normal values of areal BMD in the axial and appendicular skelskeleton. This large variance, which is observed at sites particularly susceptible to osteoporotic fractures such as lumbar spine and femoral neck, is barely reduced after correction for statural height, and does not appear to increase substantially during adult life. The height-independent broad variance in Bone Mass develops during puberty at sites such as lumbar spine and femoral neck, where the accretion rate is markedly increased.Time of peak Bone Mass attainment. Despite the fact that a majority of studies did not indicate that Bone Mass continues to accumulate significantly during the third and fourth decades, it has been generally accepted that peak Bone Mass at any skeletal site is attained in both sexes during the mid-thirties. However, recent studies indicate that in healthy Caucasian females with apparently adequate intakes of energy and calcium, Bone Mass accumulation can virtually be completed before the end of the second decade, for both lumbar spine and femoral neck. It is possible that both genetic and environmental factors could influence the time of peak Bone Mass achievement.Determinants of peaks Bone Mass. Several variables, more or less independent, are supposed to influence Bone Mass accumulation during growth; heredity, sex, dietary components, endocrine factors, mechanical forces, and exposure to risk factors. Quantitatively, the most prominent factor appears to be the genetic determinant, as estimated by studies comparing monozygotic and dizygotic twins. That heredity is not to be the only determinant of peak Bone Mass is of practical interest, since environmental factors can be modified. With respect to nutrition, the quantitative importance of calcium intake in Bone Mass accumulation during growth, particularly at sites prone to osteoporotic fractures, remains to be clearly determined. The same can be said for the impact of physical activity. Finally, the crucial years when these external factors will be particularly effective on Bone Mass accumulation remain to be determined by longitudinal prospective studies in order to produce credible and well targeted recommendations for the setting up of osteoporosis prevention programs aimed at maximizing peak Bone Mass.
Clifford J. Rosen – One of the best experts on this subject based on the ideXlab platform.
Consensus of an international panel on the clinical utility of Bone Mass measurements in the detection of low Bone Mass in the adult populationCalcified tissue international, 1996Co-Authors: Paul D. Miller, Sydney Lou Bonnick, Clifford J. RosenAbstract:
Low Bone Mass, in the asymptomatic patient, predicts future fracture risk as well as high cholesterol or high blood pressure predicts the risk of heart disease or stroke. In patients without fractures, osteoporosis can be diagnosed based on the extent of reduction in Bone Mass below mean peak Bone Mass of healthy young individuals. As Bone Mass decreases, fracture risk increases exponentially. Prevention of the first fracture is a clinical goal. Clinical situations in which an assessment of Bone Mass and fracture risk affects therapeutic decisions include estrogen deficiency, vertebral abnormalities, radiographic osteopenia, asymptomatic primary hyperparathyroidism, and longterm corticosteroid therapy. Serial measurements can also be used to monitor the effects of osteoporosis treatment in certain situations. The appropriate technique and skeletal site for Bone Mass measurements should be chosen based on the patient’s circumstances. A clinical interpretation can enhance the value of computer-generated Bone Mass measurement reports and enhance decision making.
Seminars in arthritis and rheumatism, 1996Co-Authors: Paul D. Miller, Sydney Lou Bonnick, Clifford J. RosenAbstract:
Abstract Low Bone Mass predicts future fracture risk as well as high cholesterol or high blood pressure can predict the risk of heart disease or stroke. Prevention of the first fracture should be a clinical goal. In patients without fractures, osteopenia and osteoporosis can be diagnosed based on the extent of reduction in Bone Mass below mean peak Bone Mass of young healthy individuals. As Bone Mass decreases, fracture risk increases exponentially. Clinical situations in which an assessment of Bone Mass and fracture risk affects therapeutic decisions include estrogen deficiency, vertebral abnormalities, radiographic osteopenia, asymptomatic primary hyperparathyroidism, and long-term corticosteroid therapy. Serial measurements can also be used to monitor the effects of osteoporosis treatments. The appropriate technique and skeletal site for Bone Mass measurements should be chosen based on the patient’s circumstances and the precision of measurement. A clinical interpretation can enhance the value of computer generated Bone Mass measurement reports and improve decision making.