***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Hip fractures constitute a major health problem . For effective prevention , high-risk groups need to be identified . The objective here was to develop hip fracture risk scores while assessing the added value of bone mineral density relative to more conventional risk indicators . We prospect ively followed during 4 years a cohort of 5208 persons ( 2193 men ) aged 55 years and over from the Rotterdam Study , a population -based cohort study conducted in the Netherl and s.  Risk scores for hip fracture were constructed using several conventional risk indicators requiring interview and anthropometry only , and bone mineral density . During follow-up , 50 persons ( 14 men ) suffered hip fracture . Hip fracture risk was independently determined by age , gender , height , the use of a walking aid , cigarette smoking , and either bone mineral density or weight . We developed two risk scores , with and without bone mineral density . The observed 4-year risk ranged from 3/3389 ( 0.1 % ) to 17/169 ( 10.1 % ) for the lowest and highest category of the score including bone mineral density , respectively . For the score without bone mineral density , these risks were 8/3117 ( 0.3 % ) and 16/144 ( 11.1 % ) , respectively . The area under the receiver operating characteristic curve indicating discriminatory power was 0.88 for the risk score including , and 0.83 for the score excluding , bone mineral density ( p for difference = 0.04 ) . In conclusion , risk scores with and without bone mineral density measurement can be used for hip fracture risk assessment in elderly persons . While the score with bone mineral density has a modestly better performance , the score requiring interview and anthropometry only may be especially useful in primary care setting BACKGROUND Quantitative ultrasound of bone is a new radiation-free technique that measures bone mass and may assess bone quality . Retrospective studies have suggested that low-bone ultrasound of the calcaneus is associated with an increased risk for hip and other fractures in older women . OBJECTIVES To establish the utility of calcaneal quantitative ultrasound of bone for the prediction of fractures and to compare quantitative ultrasound of bone with bone mineral densitometry by performing a prospect i ve cohort study within the Study of Osteoporotic Fractures . SUBJECTS AND METHODS We studied 6189 postmenopausal women older than 65 years of 4 US clinical centers .  Broadb and  ultrasound attenuation ( BUA ) , a measurement of the differential attenuation of sound waves transmitted through the calcaneus , and bone mineral density of the calcaneus and hip were measured . Subsequent hip and other nonspine fractures were documented during a mean follow-up of 2.0 years . RESULTS In age- and clinic-adjusted analyses , each SD reduction in calcaneal BUA was associated with a doubling of the risk for hip fractures ( relative risk [ RR ] , 2.0 ; 95 % confidence interval [ CI ] , 1.5 - 2.7 ) ; a similar relationship was observed with bone mineral density of the calcaneus ( RR , 2.2 ; 95 % CI , 1.9 - 3.0 ) and femoral neck ( RR , 2.6 ; 95 % CI , 1.9 - 3.8 ) . After adjustment for bone mineral density of the femoral neck , BUA was still associated with an increased risk for hip fracture ( RR , 1.5 ; 95 % CI , 1.0 - 2.1 ) . Intertrochanteric fractures in particular were strongly associated with a low BUA measurement ( RR , 3.3 ; 95 % CI , 2.0 - 5.5 ) . CONCLUSIONS Broadb and ultrasound attenuation predicts the occurrence of fractures in older women and is a useful diagnostic test for osteoporosis . The strength of the association between BUA and fracture is similar to that observed with bone mineral density BACKGROUND The ability of ultrasonographic measurements to discriminate between patients with hip fracture and age-matched controls has until now been tested mainly through cross-sectional studies . We report the results of a prospect i ve study to assess the value of measurements with ultrasound in predicting the risk of hip fracture . METHODS 5662 elderly women ( mean age 80.4 years ) had both baseline calcaneal ultrasonography measurements and femoral radiography ( dual-photon X-ray absorptiometry , DPXA ) to assess their bone quality . Follow-up every 4 months enabled us to identify incident fractures . 115 hip fractures were recorded during a mean follow-up duration of 2 years . FINDINGS Low calcaneal ultrasonographic variables ( obtained from measurements of broadb and ultrasound attenuation by , and speed of sound through the bone ) were able to predict an increased risk of hip fracture , with similar accuracy to low femoral bone mineral density ( BMD ) obtained by DPXA . The relative risk of hip fracture for 1 SD reduction was 2.0 ( 95 % CI 1.6 - 2.4 ) for ultrasound attenuation and 1.7 ( 1.4 - 2.1 ) for speed of sound , compared with 1.9 ( 1.6 - 2.4 ) for BMD . After control for the femoral neck BMD , ultrasonographic variables remained predictive of hip fracture . The incidence of hip fracture among women with values above the median for both calcaneal ultrasound attenuation and femoral neck BMD was 2.7 per 1000 woman-years , compared with 19.6 per 1000 woman-years for those with values below the median for both measures . INTERPRETATION Ultrasonographic measurements of the os calcis predict the risk of hip fracture in elderly women living at home as well as DPXA of the hip does , and the combination of both methods makes possible the identification of women at very high or very low risk of fracture The construction of reference ranges that accurately represent the population at large is essential for the correct identification of osteoporosis from bone mineral density ( BMD ) measurements . In this study , reference data supplied by the manufacturer of the Lunar DPX+ bone densitometer were compared with data obtained locally . Lumbar spine , proximal femur and total body BMD measurements were made in an age-stratified r and om sample of 702 Southampton women aged 20 to 89 years . Relevant demographic and medical data were recorded for each subject using a question naire . Reference curves of BMD ( mean + /- SD ) were plotted against age for each measurement site and were found to be higher than the manufacturer 's reference values at all ages and sites . Exclusion of women with factors known to affect bone mass only served to increase this discrepancy . According to World Health Organisation definitions , osteoporosis may be identified from BMD values alone . Based upon neck of femur BMD values , 100 ( 14.8 % ) of the women in this study group were categorized as osteoporotic using local young normal reference data , compared with only 39 ( 5.8 % ) using the manufacturer 's data . By normalizing for age distribution , these findings were extrapolated to the local population where it was predicted that 26.0 % and 10.1 % of females over 50 years of age would be classified as osteoporotic using the respective reference ranges . This study clearly illustrates how the numbers of women diagnosed as osteoporotic vary with the use of different reference population To determine whether measurement of hip and spine bone mass by dual-energy x-ray absorptiometry ( DEXA ) predicts fractures in women and to compare the predictive value of DEXA with that of single-photon absorptiometry ( SPA ) of appendicular sites , we prospect ively studied 8134 nonblack women age 65 years and older who had both DEXA and SPA measurements of bone mass . A total of 208 nonspine fractures , including 37 wrist fractures , occurred during the follow-up period , which averaged 0.7 years . The risk of fracture was inversely related to bone density at all measurement sites . After adjusting for age , the relative risks per decrease of 1 st and ard deviation in bone density for the occurrence of any fracture was 1.40 for measurement at the proximal femur ( 95 % confidence interval 1.20 - 1.63 ) and 1.35 ( 1.15 - 1.58 ) for measurement at the spine . Results were similar for all regions of the proximal femur as well as SPA measurements at the calcaneus , distal radius , and proximal radius . None of these measurements was a significantly better predictor of fractures than the others . Furthermore , measurement of the distal radius was not a better predictor of wrist fracture ( relative risk 1.64 : 95 % CI 1.13 - 2.37 ) than other sites , such as the lumbar spine ( RR 1.56 ; CI 1.07 - 2.26 ) , the femoral neck ( RR 1.65 ; CI 1.12 - 2.41 ) , or the calcaneus ( RR 1.83 ; CI 1.26 - 2.64 ) . We conclude that the inverse relationship between bone mass and risk of fracture in older women is similar for absorptiometric measurements made at the hip , spine , and appendicular sites BACKGROUND Risedronate increases bone mineral density in elderly women , but whether it prevents hip fracture is not known . METHODS We studied 5445 women 70 to 79 years old who had osteoporosis ( indicated by a T score for bone mineral density at the femoral neck that was more than 4 SD below the mean peak value in young adults [ -4 ] or lower than -3 plus a nonskeletal risk factor for hip fracture , such as poor gait or a propensity to fall ) and 3886 women at least 80 years old who had at least one nonskeletal risk factor for hip fracture or low bone mineral density at the femoral neck ( T score , lower than -4 or lower than -3 plus a hip-axis length of 11.1 cm or greater ) . The women were r and omly assigned to receive treatment with oral risedronate ( 2.5 or 5.0 mg daily ) or placebo for three years . The primary end point was the occurrence of hip fracture . RESULTS Overall , the incidence of hip fracture among all the women assigned to risedronate was 2.8 percent , as compared with 3.9 percent among those assigned to placebo ( relative risk , 0.7 ; 95 percent confidence interval , 0.6 to 0.9 ; P=0.02 ) . In the group of women with osteoporosis ( those 70 to 79 years old ) , the incidence of hip fracture among those assigned to risedronate was 1.9 percent , as compared with 3.2 percent among those assigned to placebo ( relative risk , 0.6 ; 95 percent confidence interval , 0.4 to 0.9 ; P=0.009 ) . In the group of women selected primarily on the basis of nonskeletal risk factors ( those at least 80 years of age ) , the incidence of hip fracture was 4.2 percent among those assigned to risedronate and 5.1 percent among those assigned to placebo ( P=0.35 ) . CONCLUSIONS Risedronate significantly reduces the risk of hip fracture among elderly women with confirmed osteoporosis but not among elderly women selected primarily on the basis of risk factors other than low bone mineral density Abstract : To examine the risk of mortality following all clinical fractures , we followed 6459 women age 55–81 years participating in the Fracture Intervention Trial for an average of 3.8 years . All fractures and deaths were confirmed by medical record or death certificate . Clinical fractures were fractures that came to medical attention . Fracture status was used as a time-dependent covariate in proportional hazards models . The 907 women who experienced a fracture were older , had lower bone mineral density and were more likely to report a positive fracture history . A total of 122 women died  over the course of the study with 23 of these deaths occurring after a clinical fracture . The age-adjusted relative risk ( 95 % confidence intervals ) of dying following a clinical fracture was 2.15 ( 1.36 , 3.42 ) . This primarily reflected the higher mortality following a hip fracture , 6.68 ( 3.08 , 14.52 ) ; and clinical vertebral fracture , 8.64 ( 4.45 , 16.74 ) . Results were similar after adjusting for treatment assignment , health status and specific common comorbidities . There was no increase in mortality following a forearm or other fracture ( non-hip , non-wrist , non-vertebral fracture ) . In conclusion , clinical vertebral fractures and hip fractures are associated with a substantial increase in mortality among a group of relatively healthy older women We studied 336 elderly white women , of whom 22 had previously suffered a hip fracture and 22 had previously suffered a vertebral fracture . All subjects were 60 years old or older with a mean age of 73.7 years .  Measurements of ultrasonic transmission velocity ( UTV ) , broad-b and ultrasonic attenuation ( BUA ) and stiffness ( STF )  were made at the os calcis using a Lunar Achilles ultrasound device .  Measurements of lumbar spine bone mineral density ( L2–4 BMD ) and femoral neck BMD were made using dual-energy X-ray absorptiometry .  The fracture groups were significantly older and had more years since menopause than the control groups . Logistic regression showed that measurements of UTV , STF and BUA discrimin 
    Output:
    
Age is also an important factor in the relationship between bone density and the absolute risk for fracture .
Older women have a much higher fracture rate than younger women with the same bone density because of increasing risk from other factors , such as bone quality and tendency to fall ( 11 ) .