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Hip fractures – which commonly lead to premature death, high rates of morbidity, or reduced life quality – have been the target of a voluminous amount of research for many years. But has the lifetime risk of incurring a hip fracture decreased sufficiently over the last decade or are high numbers of incident cases continuing to prevail, despite a large body of knowledge and a variety of contemporary preventive and refined surgical approaches? This review examines the extensive hip fracture literature published in the English language between 1980 and 2009 concerning hip fracture prevalence trends, and injury mechanisms. It also highlights the contemporary data concerning the personal and economic impact of the injury, plus potentially remediable risk factors underpinning the injury and ensuing disability. The goal was to examine if there is a continuing need to elucidate upon intervention points that might minimize the risk of incurring a hip fracture and its attendant consequences. Based on this information, it appears hip fractures remain a serious global health issue, despite some declines in the incidence rate of hip fractures among some women. Research also shows widespread regional, ethnic and diagnostic variations in hip fracture incidence trends. Key determinants of hip fractures include age, osteoporosis, and falls, but some determinants such as socioeconomic status, have not been well explored. It is concluded that while more research is needed, well-designed primary, secondary, and tertiary preventive efforts applied in both affluent as well as developing countries are desirable to reduce the present and future burden associated with hip fracture injuries. In this context, and in recognition of the considerable variation in manifestation and distribution, as well as risk factors underpinning hip fractures, well-crafted comprehensive, rather than single solutions, are strongly indicated in early rather than late adulthood.
For many years hip fracture injuries have been identified as one of the most serious health care problems affecting older people. Much attention has consequently been placed on comprehensive efforts to reduce the incidence and severity of this condition. Indeed, some recent evidence suggests these efforts have met with some degree of success.1,2 However, the literature is unequivocal in this regard. Moreover, several current reports confirm hip fractures remain a leading cause of excessive morbidity, and premature mortality among older people.3,4 Thus, despite some positive downward trends in hip fracture incidence rates,5 these may not be occurring universally or rapidly enough to offset the immense human and social costs projected to persist over the next several decades.6
That is, given that hip fracture incidence rates rise exponentially with age, and that age specific hip fracture rates are rising for subsequent cohorts,7 as longevity increases across the globe,8 along with sedentary lifestyles that correlate with several key hip fracture determinants, it seems reasonable to speculate hip fractures will remain a serious world wide public health problem as proposed by Wehren and Magaziner in 2003.6 To this end, this paper explores if there is sufficient current support for this premise, and if so, whether concerted efforts towards prevention are desirable. By analogy it also explores whether long-term costs of this health problem of nearly US$9 billion dollars in 19956 are also likely to rise, first, because an increasing body of older people survive after hip fracture injuries as a result of better acute care. Second, because these survivors commonly encounter various degrees of progressive disability that require long-term care and extensive ongoing services.6 Third, as more adults reach the age of 85 years, these adults who are commonly in precarious health or recover more slowly when injured than younger adults, are 10–15 times more likely than those younger than 85 years to fracture a hip.9
It is the author’s view that hip fractures will continue to be of substantive importance to public health planners, particularly if as predicted, a vast majority of these injuries in the 21st century will occur in developing countries10 where the resources to deal with this problem are likely to be somewhat undeveloped, underfunded and technologically suboptimal. Another related issue is that a high percentage of hip fractures are linked with osteoporosis, which is an escalating global problem. Additionally, hip fractures, the most catastrophic complication of osteoporosis, continue to result in significant mortality and morbidity rates despite the increasing availability of effective preventative agents.11 Lastly, the costs of care for this debilitating injury are immense because they are not limited solely to the costs of functional disability and increased death rates,8 but commonly to several other factors including, a loss of the ability of the injured adult to function independently, the related costs of nursing care, rehabilitation care, and need for one or more surgeries. Thus, rather than becoming complacent given some progress in reducing anticipated rates of hip fracture in some regions, continued vigilance, plus the implementation of widespread cost-effective preventive strategies against hip fractures, as stressed by Wilson and Wallace8 and Haleem and colleagues3 remain strongly indicated.
However, to secure support for efforts to prevent hip fractures and their debilitating outcomes within an economic climate that often demands service cutbacks and fiscal restraint, and a science base that does not always stress the economic and social value of prevention, the rationale for this approach must be clearly depicted. That is, a clear case must first be made for why the issue merits specific attention, and thereafter, for what specific strategies might be set in place or emphasized to minimize the related human and economic impact.
To this end, the present review reports pertinent data from the available peer-reviewed literature detailing the distribution and possible casual factors related to hip fractures published in the peer-reviewed literature over the last 30 years. Also reported are some findings regarding second hip fractures, an often overlooked, albeit important, associated outcome of the initial injury. As well, information depicting the economic and human impact of this condition, a topic not often detailed in the related literature is presented. Finally, some recommendations for improving our understanding of this health condition including potential preventive directives against first and second hip fractures, and their debilitating consequences are provided.
The literature reviewed was primarily accessed from an array of research based articles written in English, and located in the Medline and PubMed databases and published between 1980–2009. Key terms used were: ‘hip fracture’, ‘epidemiology’, ‘incidence’, ‘prevalence’, ‘risk factors’. All related articles that reported on hip fracture rehabilitation or surgery were excluded from the report. The pertinent data was carefully examined and then categorized into the key themes of interest: distribution and prevalence, outcomes and risk factors. In terms of the author’s aims, as well as space limitations, only those risk factors deemed both consistently salient and amenable to prevention are highlighted. The magnitude and extent of the disability is included to draw attention to the need for reducing the incidence and severity of this debilitating condition. In keeping with the broad aims of the paper, the review approach adopted was largely a narrative one, and an attempt was made to simplify and tabulate themes of importance. Based on the high numbers of reports from well known research establishments and researchers, and the consistency of many reports from diverse laboratories and regions, regardless of study design, an assumption was made that the reports reviewed provided consistently valid conclusions.
While somewhat variable, data published since the early 1990s describing the occurrence of hip fractures across the globe has generally shown the age-adjusted incidence of this injury is increasing3,6 or is projected to increase.12 Accordingly, it was initially predicted that if there was a steady increase in the numbers of United States residents reaching the age of 85 years or older,13 the numbers of elderly at risk for a hip fracture would double by 2007. That is, the total number of hip fracture cases in later life was not only expected to remain significant, but was projected to rise substantively.8 At the same time, this age-associated trend in longevity was not only influencing hip fracture risk in the United States, but was also evident in The People’s Republic of China where hip fracture rates, once amongst the lowest in the world compared with more affluent countries,14 increased by 34% for women and 33% for men between 1988 to 1992.15 Similarly, in Finland, the whole population incidence rate increased approximately three fold between 1970 and 1991 with respect to both genders,16 and between 1970 and 1997, the age-specific incidence of hip fractures increased in all age groups.17
Likewise, linear increases of age-adjusted fracture incidences for men and women were reported in the Netherlands between 1972–1987 and the analysis also showed that this age-specific incidence increase was higher than that of earlier birth cohorts.18 Similar trends were noted in Japan where hip fracture incidence rates for both genders were shown to increase exponentially with age after the age of 70 years with an annual incidence among women aged 85 years and older of 2,000 cases.19 Rates in Sweden from 1966–1986 were also found to increase from 3.3 per 1,000 inhabitants to 5.1 for persons aged more than 50 years, and almost doubled in persons aged more than 80 years, with a proportional increase that was greatest for men and city dwellers.20
Indeed, despite some evidence of declining hip fracture incidence rates in North America21 and among some Swiss women,22 as people live longer, and the average age of the hip fracture patient continues to increase from 73–79 years,3 it is possible the total number of hip fractures in the world, estimated at 1.7 million in 199016 will still rise exponentially to 6.3 million by the year 2050.23 In support of this argument, it has been noted that even in those regions of the United States where downturns in hip fracture incidence rates have been recorded,21 there are still increasing numbers of adults living to higher ages. In addition, rates of downturn over a 10-year period from 1991–200022 may only reflect declines among standardized hip fracture incidence rates of institution-dwelling women, rather than a general reversal in secular trends.5 Further, the fact that more older United States adults had low femoral neck bone mass density in 2005–2006 than in 1988–1994, implies the number of United States adults at risk for future hip fractures will remain high.24 Other estimates are that there will be a sevenfold increase between the present time and 2050 in Belgium25 that will be greater in men than women if no comprehensive preventive policy is set up, and marked increases in Asia where the highest absolute increment in the elderly population will be observed.26
Moreover, high incidence rates continue to prevail in some northern Europe regions16 and these are expected to rise.6 In Germany, for example, a call for improving and developing prevention strategies against hip fractures attributable to osteoporosis currently prevails because 2050 projections of this condition are expected to increase costs exponentially between 2020 and 2050 due to changing demographics.27 In Australia, the number of hip fractures is similarly expected to double over 29 years and quadruple in 56 years.28 Furthermore, data published in 2008 covering the years 1994–2006 in Austria, showed that in contrast to findings in some countries, there has been no levelling-off or downward trend of hip fracture incidence in the Austrian elderly population. After adjusting for age and gender, the fracture increase, while small was significant and rose numerically from 11,694 in 1994 to 15,987 in 2006.29
While many studies conducted in the 1990s predicted increasing hip fracture prevalence rates in the 21st century, the current literature reveals some levelling off of these rates, especially among individuals at risk for osteoporosis. However, as the number of older adults living to higher ages increases globally, the total numbers of hip fracture cases and their related expenditures are likely to rise substantively.27 Moreover, even if some of the aforementioned data do not take into account more recent bone sparing pharmacologic interventions3 and other experimental therapies that may prevent hip bone loss,30 some published data reporting an age-specific flattening of the incidence of hip fractures,31,32 may be underestimates because they often exclude hip fracture injury cases or injuries that have occurred have not been accurately coded.3
Hip fracture incidence may also be hard to capture with precision because rates may vary depending on seasonality,33 geography,34–37 and factors other than aging.34 These include health status,38 ethnicity,38,39 gender,40–44 neuromuscular status,45 extent of urbanization,46 along with year of immigration to the United States,47 the availability, nature, and potency of current therapeutic and/or preventive measures.38,48 The method of deducing trends in hip fracture and their results can also vary substantively with the model used as demonstrated by Fisher and colleagues in the Australian context.48 In addition, along with the large variation in the age, gender, and geographic distribution of hip fractures within and across countries,44,49,50 especially challenging in efforts to effectively capture the true global burden of hip fractures is the fact there are three distinctive hip fracture sub-types, each with potentially different risk factor profiles51–53and prevalence rates.54–60
Although it is not possible to prove or disprove, it seems that the strong correlation between aging and hip fractures favors the prediction that hip fracture incidence rates will rise by 1%–3% per year in most areas of the world for both men and women in the years to come.61,62 In addition to the aging factor, a widespread lack of awareness of the importance of osteoporosis persists and prevents the widespread use of drugs with anti-fracture efficacy.63 Moreover, because not all hip fractures are related to osteoporosis,62,64 but these risk factors may not be addressed or followed-up at all adequately,64 the health care system and societal costs of hip fractures are projected to increase if concerted preventive efforts with ‘new, effective and widely applicable strategies’ are not forthcoming.65–67 These projected costs include, but are not limited to, avoidable deaths, disability, and rising costs due to higher numbers of discharges of post-hip fracture patients to continuing care institutions.68
In addition to the above mentioned factors, adults who sustain intertrochanteric fractures, whose numbers increase progressively with age, experience higher mortality, morbidity, and costs than those of cervical fractures.16 As well, despite declining hip fracture reoccurrence rates greater than anticipated in recent years,69 adults who have sustained a hip fracture are commonly susceptible to subsequent hip fractures. That is, a second hip fracture, which may be in the same location with a tendency to greater displacement or instability occurs about 6% of the time and within a four-year period post-fracture.70 Further, if Dolk71 is correct, the frequency of sustaining two hip fractures over the course of an individual’s lifetime could reach 20%. Furthermore, because new hip fractures may occur on the same side as well on the opposite side to an initial fracture, it may be possible to sustain three hip fractures over time, and according to Shroder and colleagues72 the risk of incurring a third hip fracture per 1,000 men is 8.6 and 9.8 per 1000 women, per year.
Prevention here is key again because there is no well defined pattern to clearly predict who is at risk, because contributory risk factors other than osteoporosis,73 as well as untreated osteoporosis after the first fracture can be implicated in mediating two episodes of fragility fractures.74 Other data show the incidence rate for second hip fractures can be higher than that of first hip fractures,75 and as discussed by Berry and colleagues76 one year mortality rates can be approximately 10% higher following a second hip fracture than an initial fracture.76
However, pursuing the means to prevent first and second hip fractures is very challenging, because as outlined above, and reiterated by Thomas and colleagues,77 the risk of hip fracture, which rises 100–1000-fold over six decades of age is only explained in a minor way by declining bone mineral density. Several other risk factors for hip fractures that may serve as additional therapeutic targets may be helpful for reducing the rate and severity of the hip fracture injury and its costs (see Table 1) have been the focus of a large volume of research. The predominant determinants that have been studied are discussed below and were selected as representative of those deemed consistently important as well as amenable to intervention.
In the early 1990s, research by Hayes and colleagues65 demonstrated that over 90% of hip fractures are associated with falls. Since that time, an additional body of evidence has revealed a strong association between several diverse falls-related mediators and hip fracture injuries that may be useful intervention points in efforts to reduce hip fracture incidence rates. These include: balance impairments,45,78 neuromuscular and musculoskeletal impairments,79 fall type,80 fall severity, and fall speed.65 In addition, the presence of ineffective or suboptimal protective responses, along with age-associated strength decreases,81 cognitive impairment,82 and fear of falling, a serious disorder in older people, may increase the risk of falling and fracturing the hip.83 Declines in visual perception, proprioception and/or transient circulatory insufficiencies,68,84 as well as impaired sensory-motor integration functioning,85 and unexpected perturbations are additional determinants.
A sizeable body of research over the last 30 years has also shown physically inactive elderly adults are more than twice as likely as active adults to be at risk for hip fractures (see Table 2).35,86–89 Indeed, due to its highly negative impact on bone health, muscle physiology, muscle mass, overall health status, and on vitamin D exposure,90,91 physical inactivity is currently proffered as the most salient explanatory factor for the increasingly high hip fracture rates reported by developing countries, as well as many first-world countries.85
Several researchers have concluded that muscle weakness, commonly associated with slower reflex responses83 can significantly increase the chances of falling due to unexpected perturbations, thus heightening the risk of fracturing a hip.65,92,93 Related research shows low levels of muscular strength can also heighten the risk of sustaining a hip fracture88 because of its long term negative impact on bone density94 and muscle shock absorbing capacity.95 Not surprisingly, an increased risk of falling and sustaining a hip fracture has been specifically noted in association with muscular impairments at the ankle,78 hip and knee,59,85,96,97 low body strength in general,89,96 and lower limb dysfunction.98
While body height, a nonmodifiable factor, may predispose towards a hip fracture,80,94,99–106 as outlined in Table 3, there is a consistent association between the presence of a low body mass and an increased fracture risk,106 especially among Caucasian men,107 after the age of 50 years,108 which may be amenable to intervention. This association is especially strong in individuals with low bone mineral density,109 and where a weight loss relative to maximal weight exceeds 10% of body weight.106,110 Moreover, older women with smaller body size are likely to be at high risk of fracturing their hips because of their potentially lower bone mineral density,111 as well as less soft tissue coverage of their hips than women of normal body weight.46,112
However, Parker and colleagues113 found overall body size, rather than body composition of the femoral gluteal area predicted the occurrence of a hip fracture in a cohort of postmenopausal women, and although most people who fracture their hips could be classified as being thin, Cumming and Klineberg114 and Maffulli and colleagues115 reported their patients with hip fractures tended to be overweight. Dretakis and Christadoulou116 too, noted similar rates of overweight and underweight hip fracture cases among their 373 patients. Similarly, when patients with severe dementia were excluded, Bean and colleagues92 found thinness was not necessarily associated with hip fracture. Heavier individuals may also be expected to have low levels of sex hormone-binding globulin, a prevalent finding among women with recent hip fractures,117 and several comorbid conditions that are known risk factors for falling, plus medical conditions associated with osteoporosis.118
Although hip fracture is the most serious consequence of osteoporosis,119 the literature is inconsistent in demonstrating diminished bone density is universally predictive of a future hip fracture. For example, while bone density measures at the femoral neck were found to be strongly predictive of hip fractures in both men and women in one study,120 several others have reported a considerable overlap in bone densities between hip fracture patients and age- and gender-matched controls after the age of 70 years, or no significant risk.87–89,93 In addition, Wei and colleagues119 found the effect of significant risk factors for hip fracture of direct hip impact, previous stroke, sideways fall, decreased functional mobility, or low body mass remained the same regardless of femoral neck bone density. However, bone mineral density was significantly correlated with functional mobility and low body mass, which together are predictive of falls that can result in hip fractures. It has also been observed that bone mineral density is a weaker predictor of intertrochanteric hip fractures than femoral neck fractures.121 Other data reveal comparable osteoporotic indices between cases and controls,122 and that hip fracture cases were not more osteopenic than age- and gender-matched controls.123 Moreover, Asians, who have similar, or lower bone mineral densities than Caucasians, and partake in diets low in calcium, have a low incidence rate of hip fracture, especially in women.14 Mathematical models too, cannot account for the exponential rise in hip fractures with age solely on the basis of bone density levels.124 Further, individuals with osteoarthritis and higher bone density levels than the norm are not protected against hip fractures.125
Such findings strongly suggest factors other than low bone mineral density and bone mass contribute to the risk of hip fractures. These factors include but are not limited to those that increase the risk for falling, the property of the fall surface, the geometry of the hip, body size, the degree of soft tissue coverage around the hip, and the presence of poor muscle responsiveness and muscle weakness,46,85,93,97,113,114,122 (see Table 4).
Many chronic illnesses associated with aging, in particular, arthritis and Parkinson’s disease, substantially increase the risk of falling, and hence the likelihood of incurring a hip fracture.126–128 In addition, arrhythmias, postural hypertension, and peripheral neuropathies may increase the risk of falls and hip fractures,67 as may the presence of Alzheimer’s disease129 and other neurological conditions, such as stroke.130 Diabetes mellitus,131 hyperthyroidism,132 and medical conditions associated with osteoporosis,133 other forms of disability associated with the risk of falling,133 use of walking aids,134 as well as prolonged immobilization,46 may also increase the risk of sustaining a hip fracture. Rehospitalization after hip fracture may also be influenced negatively by the presence of comorbid clinical problems,135 as may outcomes of acute hip fracture if multiple problems exist, especially respiratory disease or malignancy.136
In addition to the aforementioned factors, depression, and/or the presence of one or more cognitive impairments may heighten the risk of falling and fracturing a hip.94,126,128,135,137–139,144–146 Similarly, a prevailing cognitive impairment may impact the effectiveness of postoperative rehabilitation strategies after hip fracture surgery,140 and increases the risk of falling after a hip fracture.141 The individual with mental deterioration who trips and fails to break their fall may be especially vulnerable to fracturing the hip if already weak and osteoporotic due to poor nutritional status.142
Impaired vision may be an independent risk factor for hip fracture.83,126,143 Evidence for this has been provided by Ivers and colleagues in a prospective study of 3,654 adults aged 49 years or older for five years143 and by Ivers and colleagues144 in a case-control study of 911 cases and 910 controls aged 60 years or older. In the latter study, the population attributable risk of hip fracture due to poor visual acuity or stereopsis, vision wherein two separate images from two eyes are successfully combined into one image in the brain, was 40%. In their more recent prospective study, Ivers and colleagues found visual impairment to be strongly associated with risk of hip fracture in the next two years. Pfister and colleagues145 also noted impaired vision was prevalent among women aged 50 years and older with proximal hip fractures. Impaired vision has also been associated with hip fractures occurring in the hospital146 and among the Framingham Study Cohort,147 where those with poor vision in one or both eyes had an elevated fracture risk and those with moderately impaired vision in one eye and good vision in the other had a higher risk of fracture than those with a similar degree of binocular impairment.
Although Rashiq and Logan,148 who examined the role of drugs in hip fractures found that with the exception of antibiotics, fracture risk was lower in those taking drugs, drugs reported to be related to falls that may lead to a hip fracture include: cimetidine, psychotropic anxiolytic/hypnotic drugs, barbiturates (which may also decrease bone quality), opioid analgesics, and antihypertensives,126,137 long-acting benzodiazepines, anticonvulsants, and caffeine.89 Tranquillizers, sedatives, and exposure to any of the three classes of antidepressants is associated with a significant increase in the risk of falling and sustaining a hip fracture.66,67,149 In particular, long-acting sedatives and alcohol that can slow reaction time may partly explain the increased risk of hip fractures associated with use of sedatives and regular alcohol intake.124,136,134 Alternately, alcohol abuse may result in a negative bone balance,150 decreased balance, impaired gait, and heightened risk-taking behaviors.151 Additionally, tricyclic antidepressants may increase the risk for hip fracture due to their detrimental cardiovascular side-effects, and/or their side-effects of sedation and confusion.152 Use of corticosteroids is also a documented risk factor for hip fracture,46 and may reflect the detrimental effect of corticosteroids on bone mineral density, as may levothyroxine when used by males.153 Smoking cigarettes or a pipe,98 and the consumption of tea, and fluorine concentrations over 0.11 mg per liter154 also increases the risk of hip fracture,17,98 as do benzodiazepines.155
Although many preventive programs against hip fracture focus on environmental factors, of the many factors that can influence hip fracture risk, Norton and colleagues156 found only 25% of falls that could lead to a hip fracture were associated with an environmental hazard. Further, while environmental factors may undoubtedly be a precursor to injurious falls157 a study by Allander and colleagues158 found a very low correlation between the number of risk factors of the faller and the environment.
In summary, age, a variety of age-associated physiological changes, low levels of physical activity participation, poor nutrition practices, and some forms of medication may impact two crucial determinants of hip fracture, namely femoral bone strength, and the propensity to falls. In addition, declining muscle, cognitive, visual and neural reflex responses, are likely to impact the propensity of older adults towards hip fracture injuries.45 The overlapping relationship between these factors as portrayed in Figure 1 are also likely to impact recurrent falls, and second or new hip fractures following a hip fracture159 and may also explain partly why hip fracture incidence rates vary, and remain substantive in many regions (see Table 5).
Conversely, a better understanding of these factors may help in reducing the persistent and debilitating outcomes of hip fracture injuries portrayed in Table 6.
As outlined in the body of the paper, despite some successes in reversing predicted hip fracture trends in some regions, many current reports continue to describe increasing or rising hip fracture trends in other regions (see Table 4). Although it is consequently impossible to determine if the projected global incidence of hip fracture cases is likely to reach 4.5 million by 2050 as predicted,4 it seems fair to anticipate increases in some regions.
For example, hip fracture incidence rate increases, rather than decreases are expected in Asia, Latin America, the Middle East, and Africa as a result of increases in their elderly populations.16 Similarly, hip fractures in people aged 60 years and older living in central Australia are predicted to almost double by 2011 and increase 2.5-fold and 5.4-fold by 2021 and 2051, respectively.160 A current Norwegian study has further revealed regions of the country where high lifetime absolute fracture risk rates among adults aged 25 years and older are predicted based on 1995–2004 data.161 Another related report showed annual decreases in New York State between 1985 and 1996 were not uniform in all age, gender, and race groups.162 In addition, in 2008, Auron-Gomez and163 from the Cleveland Clinic stated the incidence of hip fractures in the United States of approximately 250,000 per year is expected to double in 30 years.
Moreover, as outlined by Abrahamsen and colleagues164 and summarized in Table 5, even in regions where hip fracture rates are declining, the very stark human impact of sustaining one or more hip fractures supports a continued global effort to minimize this burden. As well, the economic consequences of hip fracture continue to rise, despite declining lengths of hospital stay.66
However, because many variations in hip fracture prevalence rates exist, and multiple, rather than single risk factors preside interventions to reduce their prevalence are difficult to develop without further research.44 In addition, the correlation between hip fractures and low bone density is not a perfectly positive one,165 and thus more insightful studies to better elucidate the etiology of hip fracture variants is indicated as outlined almost 20 years ago by Cummings and Nevitt.124 In this regard, as Leibson and colleagues64 have pointed out, hip fracture prophylaxis and its potential savings may be overestimated by studies that fail to consider differential risk, mortality and long-term follow-up data. Moreover, even though Chang and colleagues166 emphasized the need for early osteoporosis prevention in both men and women because over 48% of hip fractures in men and 66% of those in a white population in Australia were found to incur hip fractures before the ages of 80 and 85 years, respectively, Lippuner and colleagues63,64 note there is a significant lack of awareness of this disease and its consequences and this warrants attention. In addition, there are few carefully designed prospective studies that examine the nature of the age-specific increase in incidence, and whether this is due to changes in the etiology of the fracture, and not just the consequence of demographic change as postulated by Boyce and Vessey in 1985.167
What is known, is that to prevent unwarranted increases in hip fracture incidence rates and their secondary complications and costs, careful consideration of their multifactorial causation is imperative.3,36,162,168 Other promising strategies include the development of routine risk-factor assessments for older adults,169 improved study designs that examine the predictive role of novel factors in mediating hip fractures,40 the reduction of remediable visual, hearing, and combined impairments among aging cohorts,170 and encouraging the avoidance of excessive alcohol, and psychotic drugs among people at risk for first or second hip fractures. Factors that may be especially useful to examine regularly during annual check ups are listed in Box 1 and others warranting attention include those potential predictors outlined by Wilson and colleagues59 such as health insurance status, and educational level.
In the context of preventing secondary disability and poor outcomes, careful analyses of the type of fracture involved, the etiology of the fracture, and the appropriate timing of tailored interventions may be crucial.160,171 Identifying risk factors that explain gender differences in risk and outcome,171 as well regional variations could potentially impact hip fracture incidence rates as well.162 Examining the role of the health care system in the context of explaining hip fracture variants and the prevailing degree of health or disability may also be helpful.
In summary, because hip fracture risk rises exponentially with age,44,172 hip fractures are likely to remain an important public health problem despite declining incidence trends in some regions.159 Indeed, high numbers of aging adults will continue to be impacted globally by this injury,160,173 because by 2031 approximately 45% of all hip fracture cases will be aged 85 years or older.164
As well, regardless of progress in reducing hip fracture incidence in some regions, high levels of disability among survivors persists, and a high proportion of hip fracture cases, particularly men174,175 and those older than 75 years, continue to die at increased rates within the first three to six months of their injury.171 Those with comorbidities,140,175, 176,178 and poor mental status – which are likely to continue to be consistent features among aging populations – are especially vulnerable.133,178 Other factors that predict poor post-hip fracture outcomes are less than optimal follow-up of survivors,179 limited prefracture mobility,180–182 a variety of psychosocial factors,183 the patient’s general medical condition,184,178 balance status,185 their propensity towards falling,186 and eye and neurological diseases.187
To offset the predicted hip fracture burden,35 careful study of hip fracture variants,164 collecting and carefully analyzing routinely collected data188 for evidence of clinical risk factors other than bone mineral density,165,189 establishing a standard method for determining hip fracture incidence,50 and more vigilance in secondary prevention contexts is recommended.3 As well, more epidemiological studies to elucidate trends in hip fracture occurrences due to demographics, age, gender, ethnicity,6 health care setting,168,190 and health care system diversity166 are desirable. Public health organizations in developing countries are especially encouraged to develop innovative preventive strategies,191 and high risk adults, especially those with comorbid diseases,178 low body mass and low income,192 and elders in institutions at high risk for first and second hip fractures, excess mortality and poor outcomes,168,171,190,193 should be targeted.50 In addition, men who appear increasingly vulnerable to hip fracture43 should be targeted.194 Aging adults should have access to timely preventive strategies,159 including osteoporosis prevention,166 and be encouraged to maintain physically active lifestyles, and appropriate body weights.119,195
The author reports no conflicts of interest in this work.