Hip Fracture Incidence in East and West Germany: Reassessement Ten Years after Unification

The rising incidence of hip fractures is of world wide concern. In addition to the demographically aging populations world wide a secular trend of hip fracture incidence has been reported for various populations. The objective of the current study was to reassess hip fracture incidence ten years following German reunification and compare incidence rates in former East and West Germany.  Data from the German hospital discharge diagnosis registry were used to compare rates in former East and West Germany. A reassessment of a secular trend was done with directly age-standardized rates of the population 60 years old and over.  Significant differences were found between incidence rates in the East and West German states with higher rates in the West. Compared to earlier studies for East Germany, rate in East Germany have increased by on average annually 6% since reunification. This is a steep increase compared to the annual rise by about 3% between 1974 and 1989. Hip fracture incidence in East Germany thereby has doubled during the 25-year period from 1971 to 1996. Although the observed acceleration of a secular trend in East Germany probably has multiple causes, evidence suggests a significant influence of Western life style on hip fracture incidence. Received: 18 April 2000 / Accepted: 5 September 2000     

Factors Associated with Mortality after Hip Fracture

There is a well-known excess mortality subsequent to hip fracture, which is probably restricted to subgroups of hip fracture patients with reduced health status. We studied the association between risk factors and death in 248 hip fracture patients and 248 controls originally enrolled in a population-based case–control study. This cohort was followed for 3 1/2 years with respect to total mortality. A markedly increased mortality was found in hip fracture patients passing a mental status test at a low score [relative risk (RR) = 2.3, 95% confidence interval (CI) 1.4-3.7], in hip fracture patients reporting two or more selected chronic diseases (RR = 3.3, 95% CI 1.8–6.1), in hip fracture patients not walking outdoors before the fracture (RR = 3.2, 95% CI 2.0–5.1) and in hip fracture patients in the lower half of handgrip strength distribution (RR = 2.3, 95% CI 1.6–3.4), all compared with the control group. In contrast, hip fracture patients without these risk factors did not have increased mortality compared with the control group. This study suggests that otherwise healthy and fit patients do not have increased mortality subsequent to hip fracture. The excess mortality is restricted to persons with reduced mental status, reduced somatic health and low physical ability. Special attention should be paid to patients with such risk factors in the treatment and rehabilitation period. Received: 2 March 1999 / Accepted: 17 August 1999     

Bone Mineral Density, Hip Axis Length and Risk of Hip Fracture in Men: Results from the Cornwall Hip Fracture Study

Bone mineral density (BMD) and hip axis length (HAL) are important determinants of fracture risk in women. There are, however, few data concerning their predictive risk in men. The aim of this study was to determine the relationship between BMD, HAL and the risk of hip fracture in men. A case–control design was used. Cases were men aged 50 years and over with a minimal-trauma hip fracture admitted to the Royal Cornwall Hospital, Truro, during 1995–1997. Controls were recruited from a large general practice within the catchment area of the hospital. Subjects were invited for assessment of BMD at the lumbar spine and proximal femur, using dual-energy X-ray absorptiometry. HAL was assessed using machine software. Data concerning BMD were available in 62 fracture cases and 100 controls. After adjusting for age, height and weight, a reduction in BMD was associated with a significant increase in the risk of hip fracture [odds ratio (OR) 1.8–4.0 per standard deviation (SD) reduction, depending on site]. HAL was similar in both fracture and control groups (12.0 cm vs 12.0 cm). After adjusting for height, there was no association between HAL and the risk of hip fracture (OR per 1 SD increase in HAL = 0.9; 95% confidence interval 0.6, 1.3). Compared with those with a cervical fracture (n= 31), those with an intertrochanteric fracture (n= 31) had lower BMD at all skeletal sites, though this was significant for the trochanteric site only. It is concluded that BMD though not hip axis length is a risk factor for low-trauma hip fracture in Caucasian men. Received: 28 September 1999 / Accepted: 21 April 2000     

Survival after Hip Fracture: Short- and Long-Term Excess Mortality According to Age and Gender

The purpose of this study was to analyze the excess mortality after hip fracture and to reveal whether, and eventually when, the excess mortality vanished in different groups of age and gender. A population-based, prospective, matched-pair, cohort study among persons 50 years of age and older was conducted involving 1338 female and 487 male hip fracture patients with 11 086 and 8141 controls respectively. Occurrence of hip fracture and mortality were recorded from 1986 until 1995. We studied the excess mortality of the hip fracture patients versus controls by using Kaplan–Meier curves and extended Cox regression with hip fracture (yes/no) as time-dependent covariate. The male hip fracture patients had higher mortality than the women the first year after the injury, irrespective of age, both in absolute terms (31% and 17% respectively) and relative to their age-matched controls. The relative risk (RR) of dying within 1 year for hip fracture patients versus controls was 3.3 (95% confidence interval (CI) 2.1–5.2) for women and 4.2 (95% CI 2.8–6.4) for men below 75 years of age. The corresponding figures for persons 85 years and older were 1.6 (95% CI 1.2–2.0) for women and 3.1 (95% CI 2.2–4.2) for men. All groups of age and gender, except women 85 years and older, had a large and significant excess mortality lasting for many years after the hip fracture – at least 5–6 years for women below 75 years of age (RR = 3.2, 95% CI 1.9–5.6). The excess mortality after hip fracture for women 85 years and older had vanished after 3 months (RR = 1.0, 95% CI 0.8–1.1). When referring to the excess mortality after hip fracture it is therefore necessary to specify sex, age and time since injury. Received: 15 September 1998 / Accepted: 23 December 1998     

Evaluation of Osteoporosis Treatment in Seniors after Hip Fracture

A retrospective chart review was carried out on all consecutive patients over 65 years of age admitted to a tertiary care teaching hospital with a diagnosis of a new hip fracture. A further chart review occurred after discharge from post-surgery rehabilitation. The primary objective was to evaluate the prevalence of osteoporosis diagnosis and treatment in both phases of the study. Secondary objectives included evaluation of the mortality rates, length of stay, prevalence of osteoporosis investigation, and prevalence of osteoporosis diagnosis based on the clinical subspecialty involved. There were 311 patients evaluated in the initial phase, and 226 after rehabilitation. The mortality rate was 5.8% (10% for men, 4% for women; p<0.005) in the acute care hospital and 9.3% (8% men, 10% women) during rehabilitation. Previous hip fracture occurred in 17.4%, and 1.5% were readmitted during the study period with fracture of the opposite hip. Osteoporosis was diagnosed in the acute care hospital on admission in 11.9% and on discharge in 15.4%. In the rehabilitation hospital it was diagnosed in 9.7% on admission and 11.2% on discharge (p = NS). Osteoporosis treatment (including calcium or vitamin D therapy) was instituted in 13% on admission to acute care and in 9.7% at the time of discharge. For the rehabilitation hospital, treatment occurred in 12.8% on admission and 10.2% on discharge. The diagnosis of osteoporosis significantly increased the prevalence of treatment (p<0.001). Use of specific agents (hormone replacement therapy, bisphosphonates or calcitonin) occurred in <6% of all patients. Osteoporosis is under-diagnosed and under-treated in this group of elderly hip fracture patients. It is associated with significant mortality and morbidity and every effort should be made to prevent future fractures. Physicians in the “front line” of hip fracture treatment are missing this key aspect of management in their patients. Education of these physicians, as well as the public, may be the key to addressing this care gap. Received: 12 March 2001 / Accepted: 23 July 2001     

Characteristics of Falls and Risk of Hip Fracture in Elderly Men

The steep rise in hip fracture incidence rates with age is not fully explained by an increase in the frequency of falls or by reduction in bone mineral density, suggesting that circumstances of falls may also affect the risk of hip fracture. Previous studies conducted mainly among women have identified the importance of the orientation of a fall in the etiology of hip fracture. In this case–control study among men of 45 years and older, we evaluated how the circumstances of falls affect the risk of hip fracture. We compared 214 cases with hip fracture due to a fall with 86 controls who had fallen within the past year but did not sustain a hip fracture. As expected, in multivariable age-adjusted analyses men who reported hitting the hip/thigh in a fall had a markedly elevated risk of hip fracture (OR = 97.8; 95% CI = 31.7–302). Hitting the knee in a fall was associated with reduced risk (OR = 0.24; 95% CI = 0.09–0.67). Other factors that were associated with reduced risk of hip fracture among men who fell were more hours of physical activity in the past year (OR = 0.84; 95% CI = 0.73–0.97, for each additional 4 h per week), a greater body mass index (OR = 0.60; 95% CI = 0.40–0.90, for each additional 4 kg/m²), and a history of a fracture when age 45 years or older (OR = 0.26; 95% CI = 0.10–0.69). Reported lower limb dysfunction was associated with increased risk of hip fracture (OR = 6.41; 95% CI = 2.09–19.6) among fallers. The increased risk associated with hitting the hip/thigh in a fall and the reduced risk associated with high body mass index suggest that preventive efforts for older men at high risk might include protective hip pads to reduce the force on the hip in a fall. Exercise and strength training programs may also reduce the risk of hip fracture among men who fall. Received: 12 May 1997 / Accepted: 14 October 1997     

Hip Fracture Epidemiology in Greece During 1977–1992

Hip fracture, the most dramatic complication of osteoporosis, constitutes a serious health problem of the elderly, with great socioeconomic consequences. Hip fracture epidemiology has been studied by many investigators. Until now, reported studies in Greece include either data from only one region, or they do not include all the epidemiological parameters concerning hip fractures. We studied hip fractures that occurred in Greece in 1992 and compared the findings with those of previous years (1977, 1982, 1987), in order to identify age and sex incidence and increase rate during 1977–1992. There has been an average annual increase of 7.6%, thus total hip fractures in Greece increased from 5,100 in 1977 (54.75 fractures/100,000 inhabitants) to 10,953 in 1992 (107.30 fractures/100,000 inhabitants). In 1992, 70% of the patients were women. During the 1977–1992 period, age-adjusted incidence for people aged over 50 increased in both sexes (from 173.54 fractures/100,000 inhabitants in 1977 to 314.07 fractures/100,000 inhabitants in 1992, an increase of age-adjusted incidence of 80.97%). Approximately 50% of the patients in 1992 were aged 80 and over, whereas in 1977 there were only 22.49% patients of the same age. The increase in hip fracture numbers is greater than expected due to population aging, suggesting the existence of other factors influencing this increase. The most affected age group is 80 and over. Received: 3 June 1997 / Accepted: 9 October 1997     

Hip Fracture Prevention Trial Using Hip Protectors in Japanese Nursing Homes

A method to protect the hips during falls could effectively reduce the incidence of hip fractures. We report the results of the first hip protector trial in Japan, performed between July 1996, and September 1999. One hundred and sixty-four elderly female residents of nursing homes, with Activities of Daily Living above the wheelchair level, agreed to participate in this study. Among them, 88 were randomly selected to wear a hip protector and 76 controls did not. All falls and resulting injuries were recorded daily. In anthropometric measurements and ultrasonic bone evaluation, no significant differences were found between the two groups, except in height. During an average of 377 days, the wearers and the non-wearers fell a total of 131 and 90 times, respectively. Among the wearers, there were two non-hip fractures and one hip fracture, so the annual hip fracture rate was calculated at 1.2%, against 8 hip fractures among the non-wearers, or 9.7% per year. The hip fracture rate was significantly lower among the wearers than non-wearers, while the annual number of falls per subject and the distribution of fallers remained the same. According to Cox’s proportional hazard regression analysis, the effect of the hip protector on hip fracture prevention was independent of anthropometric data, ultrasonic bone assessment values or number of falls. Moreover, even after limiting the subjects to fallers only, the annual hip fracture rate in non-wearers was higher than in wearers (19.8% vs 2.0%) and the annual hip fracture rate per fall in wearers was lower than that in non-wearers (0.8% vs 8.2%). It was thus concluded that the hip protector is a beneficial device for the prevention of hip fractures. Received: 8 March 2000 / Accepted: 10 October 2000     

Incremental Cost of Medical Care after Hip Fracture and First Vertebral Fracture: The Rotterdam Study

The aim of this study was to estimate the additional cost of medical care (the incremental cost) caused by incident hip and vertebral fractures, using a matched case cohort design within a longitudinal follow-up study. Incident hip fractures were recorded using the regular follow-up system of the Rotterdam Study. Incident vertebral fractures were recorded by morphometric comparison of spinal radiographs taken at intervals of 2.2 years on average. The matched control group was randomly selected from other participants of the Rotterdam Study in whom no fracture occurred during follow-up, but who were otherwise comparable at baseline. Cases were matched for age, gender, self-perceived health, ability to perform activities of daily life, living situation and general practitioner. Medical expenditure was assessed by retrieval of the general practice medical records and by recording all hospital and nursing home admissions, and all general practice and outpatient visits. Pharmaceutical consumption was recorded through the computerized records of the central pharmacy. Valid results were obtained for 44 pairs (91%) in the hip fracture and for 42 pairs (93%) in the vertebral fracture group. Cost of medical consumption in the year before the hip fracture was similar in patients and control subjects, but the incremental cost in the first year after the hip fracture was almost US$10 000. In the second year after hip fracture the incremental cost was still about $1000. Accounting for the excess mortality in hip fracture patients had little effect on cost in the first year, but cost in the second year was doubled to almost $2000. For vertebral fractures, we did not detect important acute care costs, but these fractures were associated with a yearly recurrent incremental cost of over $1000. However, almost half this difference was already present before the occurrence of the fracture, and was attributable to hospital admissions. The remainder of the incremental cost was mainly due to pharmaceutical consumption and to a lesser extent to admissions to orthopedic surgery wards. We conclude that hip fractures cause excess mortality and an important incremental cost especially during the first year, and that these could probably be avoided by prevention of hip fractures. For vertebral fractures we found no evidence of important acute care costs but we observed a yearly returning incremental cost. Part of this incremental cost, however, was pre-existing and might therefore by caused by co-morbidity. Received: 29 July 1998 / Accepted: 11 December 1998     

Survival and Potential Years of Life Lost After Hip Fracture in Men and Age-matched Women

Hip fracture is associated with a higher mortality rate in men than in women. However, mean age of men and women with hip fracture differs markedly. Thus, some of the differences in the clinical pattern and outcome between genders could be related to different ages. To avoid the influence of age on gender-specific outcome, we analyzed prefracture conditions and hip fracture outcome in a cohort of men and of age-matched women. Risk factors for low bone mass were recorded in 106 men (mean age ± SD, 80.3 ± 9.3 years) and 264 age-matched women (mean age 81.4 ± 8.0) with hip fracture. We compared mortality rate, survival, years of potential life lost and modification of housing conditions. These outcomes were prospectively assessed during an average 3.6 years follow-up (up to 7 years). Men with hip fracture differed from age-matched hip-fractured women by a higher alcohol and tobacco consumption, a greater frequency of living in couple, and by less prevalent fractures. Mortality rate after hip fracture was significantly higher in men (RR = 1.74, 95% CI 1.34–2.24). Since mortality is higher in the general male population, we compared reduction in life expectancy taking into account the gender-specific mortality rate. The excess mortality in each age-group of hip-fractured patients, which was measured during the whole follow-up period, and is an estimate of death attributable to fracture, did not differ between genders. Reduction in life expectancy due to hip fracture was similar in both genders (5.9 ± 4.5 and 5.8 ± 4.8 years, in men and women, respectively; NS), but the proportion of the years of life lost was higher in men (70 ± 33%) than in women (59 ± 42%, p < 0.01). It was concluded that for the same age, mortality rate after hip fracture was higher in men than in women. Although the reduction in life expectancy was similar in both genders, the proportion of the years of life lost was higher in men, suggesting a worse impact of hip fracture on survival in men, even after consideration of the higher mortality rate in the general male population. Received: 9 October 2001 / Accepted: 22 April 2002     

A Secular Trend in Hip Fracture Incidence in East Germany

The central Inpatient Register of the former German Democratic Republic was used to study the population-based epidemiology of hip fractures among 16.5 million East Germans. Incidence rates for hospital discharges for proximal femoral fractures for the age group 60 years and over were calculated for the years 1971 to 1989, the year before unification. Incidence rates for 1989 are similar to figures reported from the UK and The Netherlands, but lower than Scandinavian rates. A decrease in the admission rate was noted from 1971 to 1974 of 4.5% each year on average, and an increase from 1974 onwards of 4.4% on average. This change was observed to a different extent in all age groups. The female:male ratio of the standardized discharge incidence was stable at 2.3:1 and the female:male ratio of manifest cases increases from 4.1:1 in 1971 to 5.1:1 in 1989. An exponential increase in the incidence rates was observed with age. This apparent rate overestimates both the rate for true incident cases (by about 25–30%, if adjustments are made for readmissions and transfers) and their trend. Adjusted estimates for incident fractures show an increase of 2% annually. Cohort effects due to changed selective forces appear to be one reasonable causal explanation. Received: 28 November 1997 / Accepted: 29 May 1998     

Economic Implications of Hip Fracture: Health Service Use, Institutional Care and Cost in Canada

As the burden of illness associated with hip fracture extends beyond the initial hospitalization, a longitudinal 1 year cohort study was used to analyze levels of health service use, institutional care and their associated costs, and to examine patient and residency factors contributing to overall 1 year cost. Patients in the study were aged 50 year and over, and had been admitted to an acute care facility for hip fracture in the Hamilton–Wentworth region of Canada from 1 April 1995 to 31 March 1996. Health care resources assessed included initial hospitalization, rehospitalization, rehabilitation, chronic care, home care, long-term care (LTC) and informal care. Regression analysis was used to determine the effects of age, gender, residence, survival and days of follow-up on 1 year cost. The mean 1 year cost of hip fracture for the 504 study patients was 26.527 Canadian dollars (95% Cl: $24.564–$28.490). One year costs were significantly different for patients who returned to the community ($21.385), versus those who were transferred to ($44.156), or readmitted to LTC facilities ($33.729) (p<0.001). Initial hospitalization represented 58% of 1 year cost for community-dwelling patients, compared with 27% for LTC residents. Only 59.4% of community-dwelling patients resided in the community 1 year following hip fracture, and 5.6% of patients who survived their first fracture experienced a subsequent hip fracture. Linear regression indicated place of residence, age and survival were all important contributors to 1 year cost (p<0.001). While the average 1 year cost of care was $26.527, the overall cost varied depending on a patient”s place of residence, age, and survival to 1 year. Annual economic implications of hip fracture in Canada are $650 million and are expected to rise to $2.4 billion by 2041. Received: 4 May 2000 / Accepted: 27 October 2000     

Deterioration in Quality of Life Following Hip Fracture: A Prospective Study

To examine longitudinal change in health- related quality of life (HRQoL) following hip fracture in elderly subjects, 32 patients with hip fractures and 29 sex-matched non-fracture control subjects (mean ± SD age 82 ± 8 and 86 ± 6 years respectively) were enrolled in a prospective, case–control study. Fracture subjects completed a generic questionnaire, Short Form 36 (SF-36), and a disease-targeted measure, the revised Osteoporosis Assessment Questionnaire (OPAQ2), on two separate occasions, within 1 week of fracture and 12–15 weeks after fracture. Controls completed both questionnaires on two occasions 12 weeks apart. SF-36 scores were significantly correlated with OPAQ2 in comparable domains of Physical Function (r= 0.76), General Health (r= 0.70) and Mental Health/Tension (r = 0.86). Control subjects had stable scores with the OPAQ2 and SF-36. At 3 months after fracture there was a significant reduction in HRQoL in the SF-36 domains Physical Function (–51%), Vitality (–24%) and Social Function (–26%) and in the OPAQ2 domains Physical Function (–20%), Social Activity (–49%) and General Health (–24%). Hip fracture patients thus had a lower baseline HRQoL and experienced a significant deterioration in HRQoL after hip fracture on both the SF-36 and OPAQ2. HRQoL should be part of a comprehensive assessment of the costs of osteoporosis including fracture-associated morbidity. Received: 21 October 1999 / Accepted: 15 November 1999     

How Hip and Whole-Body Bone Mineral Density Predict Hip Fracture in Elderly Women: The EPIDOS Prospective Study

We conducted a population-based cohort study in 7598 white healthy women, aged 75 years and over, recruited from the voting lists. We measured at baseline bone mineral density (BMD g/cm²) of the proximal femur (neck, trochanter and Ward's triangle) and the whole body, as well as fat and lean body mass, by dual-energy X-ray absorptiometry (DXA). One hundred and fifty-four women underwent a hip fracture during an average 2 years follow-up. Each standard deviation decrease in BMD increased the risk of hip fracture adjusted for age, weight and centre by 1.9 (95% CL 1.5, 2.3) for the femoral neck, 2.6 times (2.0, 3.3) for the trochanter, 1.8 times (1.4, 2.2) for Ward's triangle, 1.6 times (1.2, 2.0) for the whole body, and 1.3 times (1.0, 1.5) for the fat mass. The areas under the receiver operating characteristic (ROC) curves were not significantly different between trochanter and femoral neck BMD, whereas ROC curves of femoral neck and trochanter BMD were significantly better than those for Ward's triangle and whole-body BMD. emsp;Women who sustained an intertrochanteric fracture were older (84 ± 4.5 years) than women who had a cervical fracture (81 ± 4.5 years) and trochanter BMD seemed to be a stronger predictor of intertrochanteric ([RR = 4.5 (3.1, 6.5)] than cervical fractures ([RR = 1.8 (1.5, 2.3]). emsp;In very elderly women aged 80 years and more, hip BMD was still a significant predictor of hip fracture but the relative risk was significantly lower than in women younger than 80 years. emsp;In the 48% of women who had a femoral neck BMD T-score less than –2.5, the relative risk of hip fracture was increased by 3, and the unadjusted incidence of hip fracture was 16.4 per 1000 woman-years compared with 1.1 in the population with a femoral neck BMD T-score 5–1. Received: 19 May 1997 / Accepted: 16 October 1997     

Maternal Height, Childhood Growth and Risk of Hip Fracture in Later Life: A Longitudinal Study

Although measures to enhance bone mineralization during childhood and adolescence are widely incorporated into preventive programmes against osteoporotic fracture, there are no published data directly linking growth rates in childhood with the risk of later hip fracture. We addressed this issue in a unique Finnish cohort in whom birth and childhood growth data were linked to later hospital discharge records. This permitted follow-up of 3639 men and 3447 women who were born in Helsinki University Central Hospital between 1924 and 1933, who went to school in Helsinki and still lived in Finland in 1971. Body size at birth was recorded and an average of 10 measurements were obtained of height and weight throughout childhood. We identified 112 subjects (55 men and 57 women) who sustained a hip fracture during 165 404 person-years of follow-up. After adjustment for age and sex in a proportional hazards model, we identified two major determinants of hip fracture risk: tall maternal height (p<0.001) and a low rate of childhood growth (height, p= 0.006; weight, p = 0.01). The hazard ratio for hip fracture was 2.1 (95% CI 1.2–3.5) among men and women born to mothers taller than 1.61 m, when compared with those whose mothers were shorter than 1.54 m. The ratio was 1.9 (95% CI 1.1–3.2) among those whose rate of childhood height gain was below the lowest quartile for the cohort, compared with those whose growth rate was above the highest quartile. The effects of maternal height and childhood growth rate were statistically independent of each other, and remained after adjusting for socioeconomic status. The patterns of childhood growth that predicted future hip fracture differed between boys and girls. In boys, there was a constant deficit in height and weight between ages 7 and 15 years among those later sustaining fractures; in girls, there was a progressively increasing deficit in weight but a delayed height gain among those later sustaining fractures. This epidemiologic study provides the first direct evidence that a low rate of childhood growth is a risk factor for later hip fracture. Whether reduced growth rate is a consequence of childhood lifestyle, genetic background or intrauterine hormonal programming, the data support measures to optimize childhood growth as part of preventive strategies against osteoporotic fracture in future generations. Received: May 2000 / Accepted: June 2001     

Long-Term Fracture Risk Following Ischemic Stroke: A Population-Based Study

The overall risk of fracture following stroke has not been well quantified. We addressed this issue in a population-based retrospective cohort study among the 387 Rochester, Minnesota residents who survived for 90 days following their first cerebral infarction during the 10-year period, 1960–69. Cases were matched by age and sex to controls from the general population of Rochester, and subsequent fractures were assessed through review of each subject’s complete (inpatient and outpatient) medical records in the community. With comparable follow-up, the 128 fractures observed among cases were little more than the 118 seen among controls, and the cumulative incidence of any fracture after 25 years was not significantly different (71% versus 66%; p=0.464). Using stratified Cox analysis, there was no increase in the risk of fractures generally (hazard ratio (HR), 1.1; 95% CI, 0.8–1.6) or hip fractures specifically (HR, 1.1; 95% CI, 0.6–2.1) compared with controls. Among the stroke patients with hemiparesis or hemiplegia, the majority of fractures occurred on the impaired side. In a multivariate analysis, fracture risk increased with age (HR per 10 years, 1.6; 95% CI, 1.4–2.0), with hospitalization at onset of stroke (HR, 2.0; 95% CI, 1.3–3.2) and with moderate functional impairment (HR, 1.6; 95% CI, 1.02–2.5) but not severe disability (HR, 0.8; 95% CI, 0.4–1.6). No other characteristic of the stroke or its treatment was an independent predictor of overall fracture risk. Patients and their caretakers need to be aware of the risk of fracture from falls, particularly when moderate impairment permits the patient to be independently mobile. Received: 29 September 2000 / Accepted: 26 April 2001     

Changes in Bone and Calcium Metabolism Following Hip Fracture in Elderly Patients

Although hip fracture is one of the most common causes of acute immobilization in elderly patients, little is known about the influence of immobilization on changes in bone and calcium metabolism following this event. We therefore compared serum biochemical indices of bone and calcium metabolism in 20 elderly subjects with hip fracture with those measured in 20 healthy age-matched controls. Rankin scores, a measure of functional dependence with 0 representing independence and 5 representing total dependence, were assigned. We also examined serial changes in these biochemical indices from shortly following the fracture to the early recovery period. Ionized calcium, intact parathyroid hormone (PTH), intact bone Gla protein (BGP), pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), 25-hydroxyvitamin D (25-OHD), and 1,25-dihydroxyvitamin D (1,25-[OH]₂D) were measured. One week after the fracture, mean serum concentrations of calcium and ICTP were elevated in correspondence to degree of immobilization (mean Rankin score; 4.4), while serum concentrations of BGP, PTH, 25-OHD, and 1,25-[OH]₂D were depressed. Rankin score (mean: 4.4) correlated positively with ICTP and negatively with BGP at this time. At 2 months, calcium and ICTP elevation decreased and BGP, PTH and 1,25-[OH]₂D were less depressed, coinciding with a decline in Rankin score from 4.2 to 2.2. Indices were further improved at 3 months (mean Rankin score, 1.3), with calcium and BGP returning to normal. We concluded that increased bone resorption, and decreased bone formation, and hypercalcemia are present by 1 week following the hip fracture, and some resorption increase persists for at least 3 months. These changes could explain in part the high risk of another hip fracture. Received: 3 April 2000 / Accepted: 15 December 2000     

Comparison of Six Calcaneal Quantitative Ultrasound Devices: Precision and Hip Fracture Discrimination

Quantitative ultrasound (QUS) is now accepted as a useful tool in the management of osteoporosis. There are a variety of QUS devices clinically available with a number of differences among them, including their coupling methods, parameter calculation algorithms and sites of measurement. This study evaluated the abilities of six calcaneal QUS devices to discriminate between normal and hip-fractured subjects compared with the established method of dual-energy X-ray absorptiometry (DXA). The short-term and mid-term precisions of these devices were also determined. Thirty-five women (mean age 74.5 ± 7.9 years) who had sustained a hip fracture within the past 3 years, and 35 age-matched controls (75.8 ± 5.6 years) were recruited. Ultrasound measurements were acquired using six ultrasound devices: three gel-coupled and three water-coupled devices. Bone mineral density was measured at the hip using DXA. Discrimination of fracture patients versus controls was assessed using logistic regression analysis (expressed as age- and BMI-adjusted odds ratios per standard deviation decrease with 95% confidence interval) and receiver operating characteristics (ROC) curve analysis. Measurement precision was standardized to the biological range (sCV). The sCV ranged from 3.14% to 5.5% for speed of sound (SOS) and from 2.45% to 6.01% for broadband ultrasound attenuation (BUA). The standardized medium-term precision ranged from 4.33% to 8.43% for SOS and from 2.77% to 6.91% for BUA. The pairwise Pearson correlation coefficients between different devices was highly significant (SOS, r= 0.79–0.93; BUA, r= 0.71–0.92). QUS variables correlated weakly, though significantly, with femoral BMD (SOS, r= 0.30–0.55; BUA, r= 0.35–0.61). The absolute BUA and SOS values varied among devices. The gel-coupled devices generally had a higher SOS than water-coupled devices. Bone mineral density (BMD) and BUA were weakly correlated with weight (r= 0.48–0.57 for BMD and r= 0.18–0.54 for BUA), whereas SOS was independent of weight. All the QUS devices gave similar, statistically significant hip fracture discrimination for both SOS and BUA measures. The odds ratios for SOS (2.1–2.8) and BUA (2.4–3.4) were comparable to those for femoral BMD (2.6–3.5), as were the area under the curve (SOS, 0.65–0.71; BUA, 0.62–0.71; BMD, 0.65–0.74) from ROC analysis. Within the limitation of the sample size all devices show similar diagnostic sensitivity. Received: 2 February 2000 / Accepted: 1 May 2000     

Hip Fracture Risk and Proximal Femur Geometry from DXA Scans

In this retrospective study of hip fracture risk evaluation from hip dual-energy X-ray absorptiometry (DXA) scans, our objectives were to determine which part of the femoral neck length contributes most to the fracture risk and to define a geometric parameter better than hip axis length (HAL) for discriminating hip fracture patients. Forty-nine Caucasian women with a nontraumatic femoral neck fracture were matched on age to 49 normal women and on both age and femoral neck bone mineral density (BMD) to 49 unfractured women. In addition to BMD, geometric parameters including neck–shaft angle, neck width and several HAL segments were evaluated by discriminant analysis to determine which was the best hip fracture discriminator. Neck–shaft angle had a limited influence on the hip fracture risk. Age-related bone loss was associated with a neck width increase in unfractured and fractured patients. HAL was significantly longer in fractured patients and was a significant discriminator between fractured patients and normal controls. HAL was not significant as a discriminator between fractured and low-BMD unfractured patients. The intertrochanter–head center distance (from the intertrochanteric line to the femoral head center) coincides with the femoral lever arm and includes no segments that adapt to BMD changes, such as the greater trochanter–intertrochanter distance. Among all tested lengths, this segment was the part of HAL that discriminated best between fractured and low-BMD unfractured patients. A longer intertrochanter–head center distance increased the risk of femoral neck fracture among low-BMD patients. Including automatic measurement of this segment in standard DXA protocols may prove useful in identifying patients at high risk for hip fracture. At present, HAL remains the easier neck length to measure, but automatic evaluation of the intertrochanter–head center distance must be a goal for future image analysis development. Received: 11 April 2001 / Accepted: 3 January 2002