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Notes: Abstract The criteria required for an effective screening strategy for osteoporosis are largely met in Caucasian women. The disease is common and readily diagnosed by the measurement of bone mineral with single- or dual-energy absorptiometry. Such measurements have high specificity but lower sensitivity, so that the value of the technique is greater for those identified as being at higher risk. Against this background there is little evidence that osteoporosis can usefully be tackled by a public health policy to influence risk factors such as smoking, exercise and nutrition. This suggests that it is appropriate to consider targetting of treatment with agents affecting bone metabolism to susceptible individuals. Since the main benefits of the use of hormone replacement therapy (HRT) are probably on cardiovascular morbidity, the major role for selective screening is to direct non-HRT interventions. An appropriate time to consider screening and intervention is at the menopause, but screening at later ages is also worthy of consideration. Since the cost of screening is low and that of bone-active drugs is high, the selective use of screening techniques will improve the cost-benefit ratio of intervention.

Notes: Abstract. Densitometric measurements are prone to imprecision in elderly subjects and the present study was primarily designed to dissect out the effects of age and bone mineral density on proximal femur dual energy x-ray absorptiometry (DXA) reproducibility. The study comprised 17 elderly women (mean age 74.6 years, range 65–84 years), 13 early postmenopausal women with osteopenia (mean age 56.2 years, range 50-63 years), and 17 elderly men (mean age 73.8 years, range 65-86 years). Each subject was given triplicate proximal femur scans by a QDR 2000 Densitometer (Hologic Inc., Waltham, MA) with repositioning between scans. Because of subject selection in the early postmenopausal women there were no significant differences in bone mineral density (BMD) at any site among the three groups. Despite this, reproducibility errors expressed as either coefficient of variation (CV) % or mean standard deviation (SD) were greater in the elderly subjects, regardless of gender, when compared with the younger female subjects. The variability in measurement errors with age were least marked for the total hip and trochanteric sites. Within the elderly subjects, BMD appeared to exert little influence on measurement errors. We conclude that short-term proximal femur reproducibility is dependent on age-related factors other than BMD. There is no influence of gender on the measurement errors. It is likely that local factors (e.g., hip osteoarthritis) or general frailty may influence repositioning but this needs further exploration. In the meantime, the total hip and trochanteric sites should be used as they provide the most reproducible measurements in the elderly.

Notes: Abstract A large number of cross-sectional studies suggest that rates of bone loss decrease in the elderly, particularly at the spine and radius. For this reason it has been argued that bone mass measurements are unhelpful in assessing fracture risk in the elderly and that drugs affecting bone metabolism are less likely to be of benefit in reducing this risk. This paper reviews the assumptions on which these conclusions are based and argues that in many instances they are flawed. Indeed, studies examining rates of bone loss in the elderly either directly or by biochemical indices of bone turnover suggest that bone loss continues throughout life and may even accelerate after the age of 70 years. This conclusion supports the view that identification of patients at risk and subsequent treatment is of value in all age groups.

Notes: Abstract: Vertebral fractures may be minor or lead to pain, decreased physical function, immobility, social isolation and depression, which together contribute to quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specfic questionnaire for patients with vertebral fractures. This questionnaire, QUALEFFO, includes questions in the domains pain, physical function, social function, general health perception and mental function. QUALEFFO was validated in a multicenter study in seven countries. The study was done in 159 patients aged 55–80 years with clinical osteoporosis, i.e., back pain and other complaints with at least one vertebral fracture and lumbar bone mineral density T-score 〈−1. Patients with a recent vertebral fracture were excluded because of unstable disease. Controls were age- and sex-matched, and did not have chronic back pain or vertebral fractures. Subjects with conditions exerting a major influence on quality of life were excluded. The QUALEFFO was administered twice within 4 weeks and compared with a generic questionnaire, the Short Form 36 of the Medical Outcomes Study (SF-36). Standard spinal radiographs were made for assessment of vertebral height. Seven questions were removed from the analysis because of low response rate, linguistic ambiguities or redundancy. The 41 remaining questions were analyzed for repeatability, internal consistency and the capacity to discriminate between patients with vertebral fractures and controls. Comparison with the SF-36 was performed within similar domains by conditional logistic regression and by receiver operating characteristic (ROC) curves. The repeatability of QUALEFFO was good (kappa statistics 0.54–0.90) and 26 of 41 questions had a kappa score ≥0.70. The internal consistency of the five domains was adequate, with Crohnbach α around 0.80. All except five questions discriminated significantly between patients and controls. The median scores of QUALEFFO were significantly higher in patients with vertebral fractures than in controls in all five domain (p〈0.001), which is consistent with decreased quality of life in patients with osteoporosis. Spinal radiographs were assessed using the McCloskey–Kanis algorithm. According to this, 124 patients (78%) had vertebral fractures of ≥3 SD severity, in contrast with 7 controls (4%). Significant correlations existed between scores of similar domains of QUALEFFO and the SF-36, especially for pain, physical function and mental function. All five domains within each questionnaire discriminated significantly between fracture cases and controls. The odds ratios for pain and social function were greater for QUALEFFO, while general health perception was more discriminating using the SF-36. The ROC curve analysis of QUALEFFO indicated that all five domains were significantly predictive of vertebral fractures. When comparing similar domains of the two questionnaires, QUALEFFO domains demonstrated significantly better performance for pain, physical function and social function. The QUALEFFO total score and SF-36 physical composite score showed similar performance. In conclusion, QUALEFFO is repeatable, coherent and discriminates well between patients with vertebral fractures and control subjects. The results of this study confirm the decreased quality of life in patients with vertebral fractures.

Notes: Abstract: Bone mineral density measurements are widely used to estimate the relative risk of hip fracture. In addition, many other risk factors have been identified, some of which are known to add to the risk independently of other risk factors, including bone mineral density measurements. In this paper we develop an algorithm that converts relative risks for hip fracture to absolute (15 years and lifetime) risks, modeled on the population of Sweden. Lifetime risks increased as expected with increments in relative risk. Average lifetime risk in women at the age of 50 years was 22.7%, which increased to 64.9% when the relative risk was 6.0. In men the risk increased from 11.1% to 41.3%. The identification of high-risk groups had little effect on the specificity of assessments but increased the sensitivity over a wide range of assumptions. The increment in lifetime risk was relatively stable across all ages, reducing the complexity of computing lifetime risks from relative risk. The derivation of absolute risk from relative risk permits the optimization of selection of individuals or populations either for further risk assessment or for treatment.

Notes: Abstract: In 1994 the WHO proposed guidelines for the diagnosis of osteoporosis based on measurement of bone mineral density. They have been widely used for epidemiological studies, clinical research and for treatment strategies. Despite the widespread acceptance of the diagnostic criteria, several problems remain with their use. Uncertainties concern the optimal site for assessment, thresholds for men and diagnostic inaccuracies at different sites. In addition, the development of many new technologies to assess the amount or quality of bone poses problems in placing these new tools within a diagnostic and assessment setting. This review considers the recent literature that has highlighted the strengths and weaknesses of diagnostic thresholds and their use in the assessment of fracture risk, and makes recommendations for actions to resolve these difficulties.

Notes: Abstract: The diagnosis of osteoporosis is based on bone mass measurement. To avoid the errors associated with the measurement of spinal bone density the total hip has been accepted as the standard measurement site. This information is not available for many early measurements. We have assessed whether it is possible to derive clinically useful information about total hip bone mineral density (BMD) from measurements at other hip sites. The bone mass measurements of 46 patients participating in a current trial of therapy for osteoporosis were reviewed. The total hip BMD as directly measured was compared with that obtained from the formula: Total hip BMD = 0.48×Neck BMD + 0.62×Trochanteric BMD + 0.03. In 30 patients with follow-up data the rate of change in hip BMD over a year was also determined by both methods. In the pretreatment state there was good agreement between the two measures (r 2 = 0.96, SEE 0.012 g/cm2). If the formula was used to compute a change in total hip BMD, the agreement between both methods remained good. However, the standard error of the estimate of the change represented 59% of the observed change. This indicates that the error associated with this estimate is too great to allow clinically meaningful conclusions to be drawn from calculated total hip BMD. We conclude that, whilst it may be possible to obtain reasonable point estimates of total hip BMD from other measures in the hip, these estimates are too imprecise to allow conclusions about change in BMD to be made.

Notes: Abstract Fragility fractures are now recognized as a major public health problem. Although the prevalence of all fractures is similar among men and women, the vast majority of osteoporotic fractures occur in elderly women. These comprise vertebral compression fractures, Colles' fracture at the wrist and hip fracture, and to a lesser extent fractures at other sites. The fracture of greatest socioeco-nomic consequence in Europe is hip fracture, which increases exponentially in incidence with age. The reasons for differences in age- and sex-specific incidence relate in part to the lower bone density of women at the time of maturity (peak bone density) and the accelerated bone loss that occurs after the menopause. Women live significantly longer than men, so that the prevalence of osteoporosis amongst elderly women is six-fold that of men. The age-specific incidence of hip fracture is rising in men and women in many countries, and if the current trends in the United Kingdom continue then the number of hip fractures occurring each year will more than double over the next 20 years. There is a marked geographic distribution in the incidence of hip fractures, even in Europe. Indeed the differences in incidence between communities is greater than the differences in incidence between sexes within communities. This suggests that the importance of gonadal insufficiency in women has been overemphasized and that other factors, probably relating to genetic or lifestyle factors affecting peak bone density, account for ecological differences in incidence of hip fracture between communities.

Notes: Abstract We assessed a method for the measurement of ultrasound velocity in cortical bone of the human tibia using a probe designed to minimize the effects of surrounding soft tissues. Of four different measurement values, the maximum velocity (average of the five highest readings) gave the lowest errors of reproducibility in relation to the population variance (standardized coefficient of variation=1.8%). The maximum velocity varied according to the tibial site measured and for practical reasons the mid-tibial site was chosen for further study. The short-term intra- and inter-observer reproducibilities (coefficients of variation) were 0.35% (n=22) and 0.50% (n=27) respectively. Long-term reproducibility over 4 months in 31 subjects was 0.68%. There was no significant difference in maximum ultrasound velocity between the dominant and non-dominant tibia in 78 women (3764±209 vs 3763±199 m/s). Tibial ultrasound velocity was significantly higher in 73 premenopausal women (3999±102 m/s) than in 129 women referred for assessment of postmenopausal osteoporosis (3780±168 m/s), 26 women with steroid-induced osteoporosis (3790±188 m/s) and 4 women with hyperparathyroidism (3575±261 m/s). In premenopausal women, ultrasound velocity did not correlate significantly with age, height, weight or body mass index. In women with postmenopausal osteoporosis, ultrasound velocity decreased with age after the menopause (r=−0.47,p〈0.0001) and body weight exerted a weaker protective effect. The apparent annual decrease in velocity with age in postmenopausal osteoporosis (8.5 m/s) was comparable to the error of reproducibility. We conclude that the technique for measuring tibial ultrasound velocity is highly reproducible in relation to the distribution of values in the population and is sensitive to age- and osteoporosis-induced changes in bone. Further studies are required to examine its relationship to other indices of skeletal status to determine the biological and clinical relevance of the technique.

Notes: Abstract: Vertebral deformity is the classical hallmark of osteoporosis. Three types of vertebral deformity are usually described: crush, wedge and biconcave deformities. However, there are few data concerning the descriptive epidemiology of the individual deformity types, and differences in their underlying pathogenesis and clinical impact remain uncertain. The aim of this study was to compare the epidemiological characteristics of the three types of vertebral deformity and to explore the relationships of the number and type of deformity with back pain and height loss. Age-stratified random samples of men and women aged 50 years and over were recruited from population registers in 30 European centers (EVOS study). Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. The presence, type and number of vertebral deformities was determined using the McCloskey–Kanis algorithm. A total of13 562 men and women were studied; mean age in men was 64.4 years (SD 8.5), and in women 63.8 years (SD 8.5 years). There was evidence of variation in the occurrence of wedge, crush and biconcave deformity by age, sex and vertebral level. Wedge deformities were the most frequent deformity and tended to cluster at the mid-thoracic and thoraco-lumbar regions of the spine in both men and women. Similar predilection for these sites was observed for crush and to a lesser extent biconcave deformities though this was much less marked than for wedge deformities. In both sexes the frequency of biconcave deformities was higher in the lumbar than the thoracic spine and unlike the other deformity types it did not decline in frequency at lower lumbar vertebral levels. The prevalence of all three types of vertebral deformity increased with age and was more marked in women. There were no important differences in the effect of age on the different deformity types. All types of deformity were associated with height loss, which was greatest for individuals with crush deformity. Back pain was also associated with all types of deformity.Overall, these results do not suggest important differences in pathophysiology between the three deformity types. Biomechanical factors appear to be important in determining their distribution within the spine. All deformity types are linked with adverse outcomes, though crush deformities showed greater height loss than the other deformity types.