Race and sex differences in mortality following fracture of the hip

Quality of life related to fear of falling and hip fracture in older women: a time trade off study

OBJECTIVE

To estimate the utility (preference for health) associated with hip fracture and fear of falling among older women.

DESIGN

Quality of life survey with the time trade off technique. The technique derives an estimate of preference for health states by finding the point at which respondents show no preference between a longer but lower quality of life and a shorter time in full health.

SETTING

A randomised trial of external hip protectors for older women at risk of hip fracture.

PARTICIPANTS

194 women aged >/= 75 years enrolled in the randomised controlled trial or who were eligible for the trial but refused completed a quality of life interview face to face.

OUTCOME MEASURES

Respondents were asked to rate their own health by using the Euroqol instrument and then rate three health states (fear of falling, a "good" hip fracture, and a "bad" hip fracture) by using time trade off technique.

RESULTS

On an interval scale between 0 (death) and 1 (full health), a "bad" hip fracture (which results in admission to a nursing home) was valued at 0.05; a "good" hip fracture (maintaining independent living in the community) 0.31, and fear of falling 0.67. Of women surveyed, 80% would rather be dead (utility=0) than experience the loss of independence and quality of life that results from a bad hip fracture and subsequent admission to a nursing home. The differences in mean utility weights between the trial groups and the refusers were not significant. A test-retest study on 36 women found that the results were reliable with correlation coefficients within classes ranging from 0.61 to 0.88.

CONCLUSIONS

Among older women who have exceeded average life expectancy, quality of life is profoundly threatened by falls and hip fractures. Older women place a very high marginal value on their health. Any loss of ability to live independently in the community has a considerable detrimental effect on their quality of life.

Update on the epidemiology of osteoporosis

Osteoporosis is a major public health problem that affects the entire aging population. This report provides an update on the epidemiology of osteoporosis and its associated fractures. Published studies from 1997 to the present are highlighted. The current US prevalence estimates for osteoporosis, trends in fracture incidence rates, and latest reports on the morbidity, mortality, and costs attributable to osteoporotic fractures are discussed. Recent advances in our understanding of risk factors associated with osteoporosis and related fractures are reviewed. Special attention is paid to the rapid progress being made in the field of genetics, the growing importance of nutrition, and the new questions being raised as to the influence of hormonal factors on bone mineral density and fracture risk. New studies linking osteoporosis to several other important diseases in women including breast cancer, osteoarthritis, and stroke are also reviewed.

Monitoring skeletal response to treatment which site to measure in the femur?

In the past it was usual to interpret bone mineral density (BMD) scans of the femur using the femoral neck, trochanter, or Ward's triangle sites. Recently, a study by the International Committee for Standards in Bone Measurement recommended that the total hip should be the preferred site for the interpretation of femur BMD, and another study described a new central hip site that may offer improved precision. This article compares the longitudinal sensitivities of the different femur BMD sites for monitoring patient response to treatment. The study population was 152 postmenopausal women enrolled in a trial of a bisphosphonate therapy. Spine and hip BMD scans were performed at 0, 1, and 2 yr. The mean percentage change at 2 yr was calculated for six sites in the hip, and the spine was also included for comparison. Treatment effect was defined as the difference in the BMD change between the treated and placebo groups. Although the data analysis incorporated a term for a calibration change caused by a repair of the dual X-ray absorptiometry scanner, the effect of this event on the estimation of treatment effect was negligible. Longitudinal sensitivity was derived by dividing the treatment effect by the root mean square error (RMSE) of the statistical model. Results (and standard errors) normalized to the ratio of treatment effect: RMSE for femoral neck BMD were as follows: femoral neck: 1.00; trochanter: 1.33 (0.38); intertrochanteric: 0.84 (0.41); total hip: 1.20 (0.38); Ward's triangle: 1.03 (0.27); central hip: 1.09 (0.30); spine: 2.08 (0. 45). At none of the femur sites was the change in BMD large enough to allow monitoring of response to treatment in individual patients. However, for studies involving the follow-up of a group of subjects, the longitudinal sensitivities of the different femur sites were equal within the statistical errors of the study. In particular, total hip BMD appears to be as effective as femoral neck BMD for detecting response to treatment in the femur in the setting of a clinical trial or similar research study.

The impact of race and fractures on mortality in a postmenopausal Medicaid population

The purpose of this study was to model fractures and survival by age and race in a large postmenopausal Medicaid population. All Georgia Medicaid claims were abstracted for the years 1992, 1993, and 1994. Claims for postmenopausal women (> or =50 years of age) were retained, and patients with fractures were identified by International Classification of Diseases, Ninth Revision codes for fracture. A survival analysis was conducted using Kaplan-Meier estimators to evaluate the effect of fracture, age, and race on 3-year survival. A total of 159,400 white and black postmenopausal women were identified. The cohort with fracture totaled 5933 patients, with femoral fractures constituting 46% of all fractures. Discounting those with fracture before the study, the fracture incidence was approximately 1.2% in this postmenopausal female cohort. The survival analysis suggested that after age was accounted for, black postmenopausal women had a 42% increased risk of death within 3 years of fracture, compared with 13% for white women. However, postmenopausal black women were approximately 50% less likely to experience a fracture, and postmenopausal black women without fracture had better survival rates than comparable white women. Mortality crossover and the diminished likelihood of fracture mask the true nature of fracture survival in postmenopausal black women. Postmenopausal black women with fracture are at greater risk of dying than their white counterparts.

Comparison of force attenuation properties of four different hip protectors under simulated falling conditions in the elderly: an in vitro biomechanical study

The purpose of this in vitro biomechanical study is to determine the force attenuation capacity of four different hip protectors (KPH1, KPH2, Safehip, and Safetypants) in falling simulations in elderly subjects (falls to the side). The simulated falling conditions were created by a biomechanical testing system, which consisted of an impact pendulum, surrogate pelvis and femur, and two load cells. Three series of impact experiments were conducted in an ascending order (low, moderate-, and high-force experiments), each exceeding the literature-provided average (+/- 1 SD) fracture threshold (3100 +/- 1200 N) of the proximal femur of elderly women with a mean age of 71 years. Using a low impact force of 4330 N, the trochanteric soft tissue (20-mm-thick polyethylene foam) attenuated the peak femoral impact force to 3740 N and, accordingly, the KPH1 protector to 590 N, KPH2 to 510 N, Safehip to 1080 N, and Safetypants to 790 N. Thus, in this low force experiment, all tested protectors could reduce the peak impact force entered into the proximal femur below the aforementioned average fracture threshold area (3100 +/-1200 N) of the proximal femur of elderly women. With a moderate impact force of 7230 N, the soft tissue attenuated the peak femoral impact force to 6130 N, and the protectors to 780 N, 760 N, 2240 N, and 2760 N, respectively. Thus, with this impact force, only the KPH hip protectors could reduce the impact force clearly below the fracture threshold area. In the final series of the experiment, the peak femoral impact force was set to be so high (10,840 N) that the protector, if effective, should prevent the hip fracture in almost all cases and situations. The trochanteric soft tissue attenuated this peak impact force to 9190 N, and the tested protectors to 1360 N, 1170 N, 4640 N, and 5770 N. Thus, with the KPH protectors the force received by the proximal femur remained below the average force required to fracture the proximal femur of elderly women, whereas with the two other protectors the impact force entered into the proximal femur clearly exceeded this threshold value. In conclusion, the test results showed that, of the four tested hip protectors, the anatomically designed energy-shunting and energy-absorbing KPH protectors can provide an effective impact force attenuation in a sideways-fall simulation in the elderly, whereas the force attenuation capacity of the two other protectors seems more limited. However, the true efficacy of any protector in the prevention of hip fractures can only be evaluated in randomized clinical trials.

Osteoporosis and African American women

The incidence of osteoporosis and related fractures in African American women is half that of Caucasian women. African American women who sustain osteoporosis-related fractures have increased disability and decreased survival. Given the exponential increase in hip fracture rate among African American women over the age of 70 years, the risk of osteoporosis among this population may be underestimated. This review focuses on racial differences in women's bone mineral density (BMD) and bone metabolism and on various explanations for these observed differences. Environmental risk factors for osteoporosis and related fractures among African American women and modalities for prevention and treatment of osteoporosis are discussed. African American women begin menopause with higher BMD and have lower rates of women's bone loss after menopause, which account for their decreased incidence of osteoporosis and related fractures. The risk factors for osteoporosis among African American women are similar to those found in Caucasian women. Lifestyle interventions, such as calcium and vitamin D supplementation, smoking cessation, and increased physical activity, should be encouraged to enhance peak bone mass and to decrease bone loss. These interventions and other treatment modalities, such as hormone replacement therapy, bisphosphonates, and selective estrogen receptor modulators, should be studied further in African American women.

Mortality after all major types of osteoporotic fracture in men and women: an observational study

BACKGROUND

Mortality increases after hip fractures in women and more so in men. Little is known, however, about mortality after other fractures. We investigated the mortality associated with all fracture types in elderly women and men.

METHODS

We did a 5-year prospective cohort study in the semi-urban city of Dubbo, Australia, of all residents aged 60 years and older (2413 women and 1898 men). Low-trauma osteoporotic fractures that occurred between 1989 and 1994, confirmed by radiography and personal interview, were classified as proximal femur, vertebral, and groupings of other major and minor fractures. We calculated standardised mortality rates from death certificates for people with fractures compared with the Dubbo population.

FINDINGS

356 women and 137 men had low-trauma fractures. In women and men, mortality was increased in the first year after all major fractures. In women, age-standardised mortality ratios were 2.18 (95% CI 2.03-2.32) for proximal femur, 1.66 (1.51-1.80) for vertebral, 1.92 (1.70-2.14) for other major, and 0.75 (0.66-0.84) for minor fractures. In men, these ratios were 3.17 (2.90-3.44) for proximal femur, 2.38 (2.17-2.59) for vertebral, 2.22 (1.91-2.52) for other major, and 1.45 (1.25-1.65) for minor fractures. There were excess deaths (excluding minor fractures in women) in all age-groups.

INTERPRETATION

All major fractures were associated with increased mortality, especially in men. The loss of potential years of life in the younger age-group shows that preventative strategies for fracture should not focus on older patients at the expense of younger women and of men.

Hip fracture in elderly men: the importance of subclinical vitamin D deficiency and hypogonadism

OBJECTIVE

To determine the major risk factors for hip fracture in elderly men.

DESIGN

Prospective recruitment, followed by analysis of clinical and biochemical variables.

PATIENTS AND SETTING

Men aged 60 years and older who presented to St George Hospital (a 650-bed tertiary-care centre) in 1995, comprising all 41 men with hip fractures, as well as 41 hospital inpatient and 41 outpatient control subjects without hip fractures.

MAIN OUTCOME MEASURES

Osteoporotic risk factors (including age, body weight, comorbid illnesses, alcohol intake, cigarettes smoked, and corticosteroid use) and serum concentrations of creatinine, urea, calcium, albumin, alkaline phosphatase, parathyroid hormone, 25-hydroxyvitamin D and free testosterone.

RESULTS

There were no significant differences between the hip fracture and two control groups on any of the osteoporotic risk factors. Men with hip fracture had significantly lower mean serum 25-hydroxyvitamin D concentration (45.6 nmol/L; 95% confidence interval [CI], 36.9-52.3 nmol/L) than both inpatient (61.1 nmol/L; 95% CI, 50.0-72.2 nmol/L) and outpatient (65.9 nmol/L; 95% CI, 59.0-72.8 nmol/L) controls (P=0.007). Subclinical vitamin D deficiency (defined as <50 nmol/L serum 25-hydroxyvitamin D) was 63% in the fracture group, compared with 25% in the control groups combined (odds ratio, 3.9; 95% CI, 1.74-8.78; P=0.0007). Inpatients with and without hip fractures had significantly lower mean serum albumin, calcium and free testosterone concentrations than outpatients (P< 0.05). In a multiple regression analysis, subclinical vitamin D deficiency was the strongest predictor of hip fracture (beta [regression coefficient], 0.34+/-0.19; P=0.013).

CONCLUSIONS

Subclinical vitamin D deficiency in Australian men may contribute significantly to the development of hip fracture through the effects of secondary hyperparathyroidism, resulting in increased bone loss.

Applications of bone densitometry for osteoporosis

Over the past decade, growing awareness of the impact of osteoporosis on the elderly population and the availability of new treatments to prevent fractures have stimulated the rapid development of new radiologic techniques to assist in diagnosis. With the ability to perform high precision measurements of bone mineral density (BMD) in the spine and hip, dual X-ray absorptiometry (DXA) is well suited to meet this latter need. However, there is continuing interest in smaller, cheaper systems for assessing the peripheral skeleton that include DXA scanning of the distal forearm and a variety of devices for performing quantitative ultrasound (QUS) measurements on bone. Alongside the new equipment, new guidelines have been developed to assist in the interpretation of bone densitometry studies and, following a report by a World Health Organization working group, osteoporosis is increasingly diagnosed on the basis of the patient's T-score value (difference of BMD from young adult mean normalized to the population SD). For the future, wider provision of bone densitometry services is required to properly target the new treatments now becoming available. Since it is unlikely that conventional DXA can meet these needs, QUS is an attractive alternative, especially because this technique is now proven in its ability to predict fracture risk in the elderly and FDA approval is imminent.

Current and projected rates of hip fracture in Canada

OBJECTIVE

To determine the current values and estimate the projected values (to the year 2041) for annual number of proximal femoral fractures (PFFs), age-adjusted rates of fracture, rates of death in the acute care setting, associated length of stay (LOS) in hospital, and seasonal variation by sex and age in elderly Canadians.

DESIGN

Hospital discharge data for fiscal year 1993-94 from the Canadian Institute for Health Information were used to determine PFF incidence, and Statistics Canada population projections were used to estimate the rate and number of PFFs to 2041.

SETTING

Canada.

PARTICIPANTS

Canadian patients 65 years of age or older who underwent hip arthroplasty.

OUTCOME MEASURES

PFF rates, death rates and LOS by age, sex and province.

RESULTS

In 1993-94 the incidence of PFF increased exponentially with increasing age. The age-adjusted rates were 479 per 100,000 for women and 187 per 100,000 for men. The number of PFFs was estimated at 23,375 (17,823 in women and 5552 in men), with a projected increase to 88,124 in 2041. The rate of death during the acute care stay increased exponentially with increasing age. The death rates for men were twice those for women. In 1993-94 an estimated 1570 deaths occurred in the acute care setting, and 7000 deaths were projected for 2041. LOS in the acute care setting increased with advancing age, as did variability in LOS, which suggests a more heterogeneous case mix with advancing age. The LOS for 1993-94 and 2041 was estimated at 465,000 and 1.8 million patient-days respectively. Seasonal variability in the incidence of PFFs by sex was not significant. Significant season-province interactions were seen (p < 0.05); however, the differences in incidence were small (on the order of 2% to 3%) and were not considered to have a large effect on resource use in the acute care setting.

CONCLUSIONS

On the assumption that current conditions contributing to hip fractures will remain constant, the number of PFFs will rise exponentially over the next 40 years. The results of this study highlight the serious implications for Canadians if incidence rates are not reduced by some form of intervention.

Hip fracture in elderly men: prognostic factors and outcomes

OBJECTIVE

To examine prognostic factors and outcomes after hip fracture in men aged 60 years and older.

DESIGN AND SETTING

Cohort study of all men presenting to St George Hospital (a 650-bed tertiary care centre) with hip fractures in 1995, recruited retrospectively from medical records and evaluated prospectively at six and 12 months after fracture.

PATIENTS

51 men aged 60 years or more (and, for comparison, 51 age-matched women) who presented with hip fracture not caused by high impact injuries or local bone disease.

MAIN OUTCOME MEASURES

Prognostic factors (such as pre-existing illness and osteoporotic risk factors) and outcome data (such as fracture-related complications, mortality, and level of function as measured by the Barthel index of activities of daily living at six and 12 months postfracture).

RESULTS

Median age of the 51 men was 80 years (interquartile range, 74-86 years); four were aged under 70 years. Outcome assessment was possible for 41 men (80%). Similar proportions of men and women came from institutions (32% v. 28%), and similar additional proportions required institutionalisation after discharge (18% v. 14%). Fracture-related complications affected similar proportions of men and women (30% v. 32%), and mean length of hospital stay was similar. Fourteen per cent of men died in hospital compared with only 6% of women (P = 0.06). Men had more risk factors for osteoporosis (P < 0.01). Physical functioning (measured by the Barthel index) deteriorated significantly in men from 14.9 at baseline to 13.4 at six months (P < 0.05) and 12.4 at 12 months (P < 0.05) after fracture.

CONCLUSION

Compared with women, elderly men presenting with hip fracture have higher mortality and have more risk factors for osteoporosis. Like women with hip fracture, men are usually fragile, with pre-existing medical illness and fracture-related complications contributing to their overall poor outcomes.

Excess mortality attributable to hip fracture in white women aged 70 years and older

OBJECTIVE

The purpose of this study was to estimate the excess mortality attributable to hip fracture.

METHODS

The 6-year survival rate of community-dwelling White female hip fracture patients aged 70 years and older entering one of seven hospitals from 1984 to 1986 (n = 578) was compared with that of White female respondents aged 70 years and older interviewed in 1984 for the Longitudinal Study on Aging (n = 3773).

RESULTS

After age, education, comorbidity, and functional impairment were controlled, the mortality differential between the two groups accumulated to an excess among hip fracture patients of 9 deaths per 100 women 5 years postfracture. Among those with three or more functional impairments or one or more comorbidities, the excess was 7 deaths per 100: the effect of the fracture had disappeared in these groups by 4 years. In contrast, those with two or fewer impairments and those with no comorbidities had a continuing trend of increased mortality, with an excess of 14 deaths per 100 by 5 years.

CONCLUSIONS

There is an immediate increase in mortality following a hip fracture in medically ill and functionally impaired patients, whereas among those with no comorbidities and few impairments, there is a gradual increase in mortality that continues for 5 years postfracture.

In-hospital case-fatality of aged patients with hip fracture in Catalonia, Spain

Hip fracture case-fatality in patients aged 65 years or older was studied in patients admitted to acute care hospitals in Catalonia over a 1-year period. 1222 femoral neck fractures and 1648 pertrochanteric fractures were identified. Women (76.9%) were most frequently and significantly older than men. Average age in pertrochanteric fracture was significantly higher than cervical fracture. The overall in-hospital case-fatality rate was 6.8%. Male gender, advanced age, pertrochanteric fracture and conservative management were associated with a significantly higher case-fatality rate. Multivariate logistic regression analyses demonstrated that previously seen associations showed univariate analysis. However, because interaction was observed, association within fracture and case-fatality was studied separately by gender. Men with pertrochanteric fracture showed the greatest association for in-hospital case-fatality (OR: 3.3; 95% CI: 2-5.5) compared with women with femoral neck fractures. In models with in-hospital case-fatality or no autonomy at discharge or in-hospital case-fatality or no autonomy at discharge or readmission as dependent variables, the odds ratio of death for conservative management of hip fracture were 3.7 (95% CI: 2.3-6) and 3.1 (95% CI: 1.9-4.9), respectively. This information should be taken into consideration for further analyses for long-term outcome and resource consumption by patients with hip fracture.

Hip fractures in the elderly: predictors of one year mortality

OBJECTIVE

To determine the one year mortality following hip fracture in an ambulatory, community dwelling, cognitively intact elderly population and to examine the role of specific type, number, and severity of associated medical comorbidities.

DESIGN

Prospective, consecutive.

METHODS

Six hundred twelve elderly who sustained a non-pathologic hip fracture were followed.

RESULTS

Twenty-four patients (4%) died during hospitalization; seventy-eight (12.7%) died within one year of fracture. The factors that were predictive of mortality, based on multivariate analysis, were patient age > 85 years, preinjury dependency in basic activities of daily living, a history of malignancy other than skin cancer, American Society of Anesthesiologists rating of operative risk 3 or 4, and the development of one or more in-hospital postoperative complications; all factors other than the development of an in-hospital complication were independent of treatment.

CONCLUSION

These results indicate that efforts at reducing one year mortality after hip fracture should be directed at the prevention of postoperative complications.

The epidemiology and pathogenesis of osteoporosis

Osteoporosis is an increasing health care concern as populations age throughout the developed and developing world. The social and economic costs of osteoporosis are due to its clinical outcome of fracture which increases exponentially with age. This review will highlight some of the key epidemiological aspects of osteoporosis incorporating areas of more recent interest. These include the definition; the magnitude of the problem encompassing differing incidence and prevalence patterns of both low bone mass and fracture in different cultural groups; the social consequences of fracture, including economic costs, morbidity and mortality; the evaluation of fracture risk, including the role of bone density, bone quality and the risk of falling; as well as an overview of some of the factors involved in determining low bone mass. Bone mineral density (BMD) is the most easily measured and accurate predictor of fracture risk. For any individual, BMD is the combination of their peak bone density and subsequent bone loss, both of which are influenced by genetic, hormonal and environmental factors. An understanding of key issues relating to this important disease may lead to earlier detection of the individual at high risk for fracture and rational approach to prevention and management.

Medical expenditures for the treatment of osteoporotic fractures in the United States in 1995: report from the National Osteoporosis Foundation

Osteoporotic fractures are a significant public health problem, resulting in substantial morbidity and mortality. Previous estimates of the economic burden of osteoporosis, however, have not fully accounted for the costs associated with treatment of nonhip fractures, minority populations, or men. Accordingly, the 1995 total direct medical expenditures for the treatment of osteoporotic fractures were estimated for all persons aged 45 years or older in the United States by age group, sex, race, type of fracture, and site of service (inpatient hospital, nursing home, and outpatient). Osteoporosis attribution probabilities were used to estimate the proportion of health service utilization and expenditures for fractures that resulted from osteoporosis. Health care expenditures attributable to osteoporotic fractures in 1995 were estimated at $13.8 billion, of which $10.3 billion (75.1%) was for the treatment of white women, $2.5 billion (18.4%) for white men, $0.7 billion (5.3%) for nonwhite women, and $0.2 billion (1.3%) for nonwhite men. Although the majority of U.S. health care expenditures for the treatment of osteoporotic fractures were for white women, one-fourth of the total was borne by other population subgroups. By site-of-service, $8.6 billion (62.4%) was spent for inpatient care, $3.9 billion (28.2%) for nursing home care, and $1.3 billion (9.4%) for outpatient services. Importantly, fractures at skeletal sites other than the hip accounted for 36.9% of the total attributed health care expenditures nationally. The contribution of nonhip fractures to the substantial morbidity and expenditures associated with osteoporosis has been underestimated by previous researchers.

Secular trends in hip fracture occurrence and survival: age and sex differences

The National Hospital Discharge Survey was used to analyze secular trends from 1965 to 1993 in hip fracture incidence and in-hospital survival in the White U.S. population 50 years of age and older. Age-specific fracture rates increased significantly for males in age groups 80-84 years and 85 years and older but not for younger males. For females, age-specific rates did not change significantly over the time period. Age-specific survival rates increased for both older males and females, but the increase was greatest for the older men. Why hip fracture incidence is increasing in older males but not in females and younger males is not clear. But the high lifetime prevalence of smoking in the older cohort of males may be a factor. With rising incidence rates in elderly males, prevention efforts, which have focused primarily on women because of their high fracture rates, should target both sexes.

Health status before and mortality after hip fracture

A cohort study was done to determine the direct impact of hip fracture on mortality in older people. Survival was compared between 211 hip fracture patients from a defined area and 201 non-hip fracture control subjects randomly selected from the same area. The mortality rate 1 year after hip fracture was 21.7%; 1-year mortality in the comparison group was 4.7%. The crude hazard ratio for hip fracture and mortality was 4.0 (95% confidence interval [CI] = 2.2, 7.4); adjusting for multiple health-related variables reduced it to 3.3 (95% CI = 1.7, 6.5). This finding suggests that the observed excess mortality after hip fracture is not explained by poor prefracture health status.

Energy-shunting external hip protector attenuates the peak femoral impact force below the theoretical fracture threshold: an in vitro biomechanical study under falling conditions of the elderly

The first objective of this study was to design a hip protector that would effectively attenuate and shunt away from the greater trochanter the impact energies created in typical falls of the elderly. As the shock absorption material, the protector included the 12 mm-thick Plastazote, which was found to be the most efficient energy-absorbing material in our previous in vitro biomechanical tests. With an anatomically designed semiflexible outer shield of the protector (high density polyethylene), the impact surface was increased and the impact energy shunted away from the greater trochanter. In the second phase of the study, we determined the force attenuation capacity of this device in realistic (in vitro) falling conditions of the elderly. With the impact force of 6940 N used (a typical hip impact force measured in in vitro falling tests), the trochanteric soft tissue (25 mm-thick polyethylene foam) attenuated the peak femoral impact force to 5590 N and the tested protector to 1040 N. In the second series of this experiment, the peak femoral impact force was set to be so high (13,130 N) that the protector, if effective, should prevent the hip fracture in almost all cases. The trochanteric soft tissue attenuated this peak impact force to 10,400 N and the tested protector to 1810 N. Thus, the force received by the proximal femur still remained clearly below 4170 N, the average force required to fracture in vitro the proximal femur of the elderly in a fall loading configuration. In conclusion, our test results suggest that an anatomically designed energy-shunting and energy-absorbing hip protector can provide an effective impact force attenuation in typical falling conditions of the elderly. However, the efficacy of the protector in the prevention of hip fractures can only be evaluated in randomized clinical trials.

Better discrimination of hip fracture using bone density, geometry and architecture

Bone density predicts the risk of hip fracture. Because hip strength is determined by bone geometry and architecture as well as density, we tested which variables in geometry and architecture were independent discriminators of hip fracture and, if combined with density, improved the discrimination of fracture from non-fracture over bone density alone. The design was a case-control study. The subjects were Caucasian women over the age of 60 years who had sustained a hip fracture after the age of 58 years (n = 22), and controls matched for age and weight (n = 43) and unmatched controls (n = 317) with no history of hip fracture. Variables in density, geometry and architecture were obtained from dual-energy X-ray absorptiometry images and from radiographs of the upper end of the femur. In a univariate model, of the measures of bone mass, the best discriminator of hip fracture was bone mineral density of the neck of femur; of the geometric measurements, it was hip axis length; and of the measurements of bone architecture, it was Singh grade. In a multivariate model, these three variables were shown to be independent discriminators of hip fracture. When hip axis length was combined with bone mineral density, there was significant improvement in discrimination of hip fracture (p = 0.014), and when Singh grade was combined with hip axis length and bone mineral density there was a further significant improvement (p = 0.002).(ABSTRACT TRUNCATED AT 250 WORDS)

Age-related hip fractures in men: clinical spectrum and short-term outcomes

Clinical spectrum, treatment and short-term outcomes were assessed among the 131 Rochester, Minnesota, men who contracted an initial hip fracture due to moderate trauma during 1978-89. Three-fourths of falls leading to hip fracture occurred indoors with little seasonality, and 91% of fractures were in men 65 years of age or older. The ratio of cervical to intertrochanteric femur fractures was 1.4:1, and there was a tendency toward more neurological conditions among the patients with cervical fractures. Hemiarthroplasty and total hip replacement were mostly performed for cervical fractures, while internal fixation was preferred for intertrochanteric fractures. In-hospital mortality was 11.5%, and the 30-day case fatality rate was 16.0%. Age and postoperative deterioration of mental status significantly increased the risk of early death, the latter even after adjustment in a multivariate model, while comorbidity had a suggestive but not statistically significant influence on mortality. More than half the men were discharged to nursing homes, and 79% of the patients who survived at 1 year resided in nursing homes or intermediate care facilities or were attended by home care. Only 41% of survivors recovered their prefracture level of functioning and nearly 60% of patients limped and required a cane or walker. After implementation of the prospective payment system in 1984, the length of hospital stay was reduced, but there was no change in early mortality rates, in the duration of physical therapy following fracture or in attendance at nursing homes. The results of this population-based study demonstrate the strong impact of hip fractures on short-term outcomes in men.

Increasing age-adjusted incidence of hip fractures in Finland: the number and incidence of fractures in 1970-1991 and prediction for the future

Hip fractures in the elderly are a worldwide epidemic, and aging of the populations is increasing the burden of these fractures on the health care systems. To improve the knowledge of whether the number of hip fractures is increasing even more rapidly than can be accounted for by the demographic changes only, all patients who were admitted to Finnish hospitals in 1970, 1975, 1980, 1985, 1988, and 1991 for primary treatment of first hip fracture were selected from the National Hospital Discharge Register. There was a steady, average 7.7% annual increase in the total number of hip fractures in Finland during this period so that the number of fractures was 2239 in 1970 and 6071 in 1991. The proportion of patients aged 60 years or more increased steadily from 75% in 1970 to 91% in 1991. In 1991, 74% of the patients were women. Across the study period, the age-adjusted total incidence of hip fractures also increased in both women and men 50 years of age and over. This increase was more pronounced in men. Thus, the increasing incidence of hip fractures in Finland was not only due to the fact that the population was aging but also due to the increasing age-adjusted incidence. We conclude that the number of hip fractures in Finland is increasing more rapidly than can be accounted for by the demographic changes only and this will seriously challenge the Finnish health care system in the future.

Treatment and survival among elderly Americans with hip fractures: a population-based study

OBJECTIVES

This study was undertaken to examine the patterns of treatment and survival among elderly Americans with hip fracture.

METHODS

A 5% national sample of Medicare claims was used to identify patients who sustained hip fractures between 1986 and 1989. In comparing treatment patterns across regions, direct standardization was used to derive age- and race-adjusted percentages. Logistic regression and Cox regression were used to examine short- and long-term survival.

RESULTS

In the United States, 64% of femoral neck fractures were treated with arthroplasty; 90% of pertrochanteric fractures were treated with internal fixation. Higher short- and long-term mortality was associated with being male, being older, residing in a nursing home prior to fracture, having a higher comorbidity score, and having a pertrochanteric fracture. Blacks and Whites had similar 90-day postfracture mortality, but Blacks had a higher mortality later on. For femoral neck fracture, internal fixation has a modestly lower short-term mortality associated with it than arthroplasty has.

CONCLUSION

Variation in the treatment of hip fracture was modest, The increased delayed mortality after hip fracture among Blacks requires further study.

Subsequent hip fracture among older adults

Subsequent hip fracture among the 368 Longitudinal Study on Aging respondents who fractured their hips from 1984 through 1991 was prospectively examined. Case-by-case review of the billing records indicated that 27 subsequent hip fractures occurred, for a rate of 1 every 33.8 person-years. Multivariable proportional hazard regression revealed that increased risks of subsequent hip fracture were associated with poor perceived health status and dizziness.

Menopause and African-American women: clinical and research issues

There are currently 3.7 million African-American women aged 35-54 years, and over the next 20 years virtually all of them will experience menopause. Although menopause itself is generally thought of as a naturally occurring biological phenomenon, undergoing the process can increase a woman's risk of disease. This phenomenon is common to women in all racial and ethnic groups. Across these groups, however, the process may be subject to great variability. This article does not include issues related to all minority women, but instead focuses on menopause in African-American women. It is important to note that there may be issues among Asian and Hispanic women that are very different from those of whites and blacks. Unfortunately, there is very little epidemiologic data on menopause or its antecedents in African-American women or in women of other minority groups. To stimulate epidemiologic research into the process of menopause among African-American women, this report will examine data from clinical and government sources. A common problem is that these sources overlook aspects of menopause important for the health of black women in mid and later life, such as menopause-associated symptoms, potentially beneficial hormonal therapies, and potentially debilitating skeletal disease.