Healthy Aging

Pharmacological and Non-Pharmacological Interventions to Prevent and Reduce the Incidence of Osteoporosis in Older Adults
by Harman Bedi

The skeletal system provides an array of vital functions. These functions include support and protection of delicate tissues and vital organs, a lever against which muscles act to produce movement, and finally the human skeleton is the largest site for the storage of calcium, phosphorous, and other minerals required for a variety of bodily functions (Spirduso, Francis, & MacRae, 2005). The health of the skeletal system is often overlooked, and its presence is taken for granted. However as the human body ages, individuals begin to notice deficiencies in the bone tissue, most often noticing a rise in brittleness of bone and a subsequent increase in the frequency of fractures (Hingorjo, Syed, & Qureshi, 2008).

Bone Mineral Density

Bone mineral density (BMD) is a measure of the integrity of bone, and is defined as the amount of calcium or minerals such as phosphorous, magnesium, and boron per unit volume of bone (Spirduso et al, 2005). BMD is a component of bone mass and is easily measured through noninvasive methods and thus is often used as a surrogate marker for bone health ( Bloomfield, 2005). Bone mineral density rises to a maximum between the ages of 35 to 40 in both men and women, however men experience higher levels of bone mineral density at all ages than do women (Armstrong & Wallace, 1994). After the age of 40, both men and women experience a steady loss of bone mineral density at a rate of 1-2% per year. Women experience greater losses due to a smaller initial bone mineral density, which is further exacerbated with the onset of menopause.

Osteoporosis

Osteoporosis is a chronic and systemic skeletal disease often characterized by low bone mass and microarchitectural deterioration of bone tissue that increases bone fragility and the likelihood of injury to the skeletal system, resulting in fractures or breakage, as discussed earlier (Maclean et al, 2008). Osteoporosis, left untreated and without appropriate interventions results in the skeletal system becoming weak and unable to support the body (Hingorjo et al, 2008). Osteoporosis is a devastating disorder with significant physical, psychological, social, and financial consequences (Anonymous, 2000).

Osteoporosis and Hip Fractures

It is estimated that approximately half of all women and one quarter of all men aged 50 or greater will experience an osteoporosis related injury during their lifetime (Singer, 2006). Osteoporosis and osteoporotic fractures are a major cause of morbidity and mortality in North America and worldwide (Singer, 2006). Hip fractures have become common in men and in women. A recent study done in Europe found that hip fractures affect 1 in 4 women, and 1 in 8 men by the age of 90 (Armstrong & Wallace, 1994). It is estimated that approximately 4% of patients older than 50 years of age who suffer from a hip fracture will die in hospital, and that a further 24% will expire within one year after a hip fracture (MacLean et al, 2008). Osteoporosis is now recognized as a major chronic health expenditure (Blahos J, 2007). A recent study done in the United States reported that the total costs associated with osteoporosis and osteoporotic fractures was approximately $17 billion (MacLean et al, 2008).

As a result of the prevalence of osteoporosis, the costs to the healthcare system, and the high incidence of morbidity and mortality, it is beneficial to discuss and analyze the preventative pharmacological and non-pharmacological interventions that can be utilized to help abate the onset of osteoporosis and reduce the incidence of hip fractures in older men and post-menopausal women. The following analysis will attempt to illustrate the preventative measures that an older adult can commence to avoid complications from osteoporosis. The first mechanism discussed will be the supplementation of the diet through the use of vitamin D and calcium. The discussion will then continue in attempting to analyze how exercise can improve bone tissue health. Finally appropriate physician practices including bone density screening, and greater education in primary care with respect to managing patients who are at risk of developing osteoporosis, and those recovering from osteoporotic fractures.

Diet

Adequate nutrition in the form of a balanced diet that includes vitamins, minerals, and caloric intake are the foundations for normal growth and healthy development (Spirduso et al, 2005). Nutrition plays an important role in the growth and development of bone tissue and maintaining bone health (Gennari, 2001). The two nutrients that are essential for maintaining bone health are calcium and vitamin D (Gennari, 2001). Calcium is a mineral that is critical in the building and maintenance of bone tissue. Vitamin D is a micronutrient that is required in order to efficiently absorb calcium (Masi & Bilezikan, 1997). Long-standing research has established that adequate calcium and vitamin D intake are two of the most important nutritional features of a program designed to establish peak bone mass (Masi & Bilezikian, 1997). However, there is a growing alarming trend with respect to older adults and their dietary intake of calcium and vitamin D. Studies indicate that vitamin D insufficiencies and deficits in calcium intake are reportedly very common in elderly people who reside either at home or in an institution (Meunier, 1996). Another study reported that inadequate levels of serum vitamin D are commonly observed in older adults, especially in European countries where dairy products are not fortified with the micronutrient (Janssen, Samson, & Verhaar, 2002). Many factors predispose older adults to low levels of dietary calcium and vitamin D. Among these include avoidance of milk and other dairy products, which are a good source of calcium and are often fortified with vitamin D. Another factor is the avoidance of the sun, which is a major source of vitamin D (Masi & Bilezikan, 1997). It should be noted that reductions in sun exposure are often used as a preventative measure in reducing the incidence of skin cancer (Cranney et al, 2007). Aging causes a decrease in the ability of the body to activate vitamin D via the skin and through internal mechanisms in the digestive tract (Masi & Bilezikan, 1997). Low serum levels of calcium and vitamin D result in the secretion of parathyroid hormone (PTH), which results in bone resorption in order to elevate calcium levels in the blood. The secretion of PTH results in a condition known as secondary hyper-parathyroidism, and has been associated with femoral bone loss (Meunier, Chapuy, Arlot, Delmas, & Duboeuf, 1994). Femoral bone loss due to secondary hyper-parathyroidism results in an increase in the incidence of hip fractures (Boonen et al, 2006). Low levels of vitamin D are also associated with an increase in body sway and muscle weakness which can exacerbate the incidence of falls in older adults, resulting in injury to bone tissue (Jay, 2005). A study reported that the two primary determinants of hip fractures were falls and bone loss leading to intrinsic femoral fragility (Meunier et al, 1994).

Much of the research illustrates the subsequent risks associated with low dietary intake of calcium and vitamin D and the increased incidence of hip fractures and osteoporosis. It should also be highlighted that there is a large body of empirical evidence stating the many benefits of incorporating calcium and vitamin D through modification and supplementation of the diet. A recent study analyzing randomized control trials of vitamin D supplementation and the prevention of hip fractures found that a dose of 700 to 800 international units of vitamin D (IU/d) was observed to reduce the relative risk of hip fractures by 26% as well as non-vertebral fractures by 23% (Bischoff, Willet, Wong, Giovannucci, Dietrich, & Dawson-Hughes, 2005). Another study analyzing bone disease in the elderly reported that calcium supplements have been observed to reduce the rate of bone loss in osteoporotic patients (Gennari, 2001). This same study found that calcium supplementation had a positive effect on increasing bone mass and reducing the incidence of fractures (Gennari, 2001). This study further promoted the benefits of calcium and vitamin D supplementation, indicating that supplementing the diet with 400-800 IU of vitamin D combined with calcium can abate bone loss and improve bone density in the elderly (Gennari, 2001). Another study supported the use of calcium supplementation in combination with vitamin D as preventative treatment for osteoporosis in adults aged 50 or older (Tang, Eslick, Nowson, Smith, & Bensoussan, 2007). This study recommended that older adults should consume a minimum does of 1200 mg of calcium in combination with 800 IU of vitamin D in order to achieve the optimal therapeutic effects (Tang, Eslick, Nowson, Smith, & Benoussan, 2007). In 1998 a European report on Osteoporosis-Action on Prevention made the recommendations that for the population above 65 the recommended daily dietary allowance (RDA) for calcium is 700-800 mg/day (Gennari, 2001). This study also reported that the optimal way to achieve adequate calcium intake is through the diet, recommending foods like milk, cheese, fish, fruits, and vegetables (Gennari, 2001). A recent study analyzed the inhibition of bone turnover in postmenopausal women through the consumption of milk. After a six-week period of milk supplementation, the study found that there was a marked decrease in PTH secretion, decreasing bone turnover (Bonjour, Brandolini-Bunlon, Boirie, Morel-Laporte, Braesco, Bertiere, & Souberbielle, 2008). This study concluded that a nutritional modification in attempting to alter bone metabolism may become an effective tool in the primary prevention of osteoporosis. In further studies it was reported that vitamin D supplementation in older adults improved muscle strength, walking distance, and functional ability resulting in the cumulative effect of reducing both falls and non-vertebral fractures (Jansen et al, 2002). Another study reported that vitamin D and calcium supplementation may become an effective strategy in an attempt to improve bone mineral density, muscle strength, and reducing the risk of falls (Bischoff-Ferrari, Conzelmann, Dick, Theiler, & Stahelin, 2003). A further study found that calcium and vitamin D reversed the effects of secondary hyper-parathyroidism, as well as increasing BMD (Boogen et al, 2006). In addition to the mentioned benefits, the authors of this same study observed that calcium and vitamin D supplementation significantly improved body sway and strength in the lower extremities, resulting in a reduction of the risk of falls (Boogen et al, 2006). This study concluded that the combined effects of calcium and vitamin D supplementation on decreasing PTH secretion, improving BMD, and improving musculoskeletal strength in the lower extremities provides a strong rationale for the use of calcium and vitamin D supplementation as a method of preventing and treating osteoporosis and osteoporotic fractures (Boogen et al, 2006). Additional studies have concluded that it is possible to mitigate and cease bone loss in the elderly as well as prevent hip fractures through vitamin D calcium supplementation (Meunier, 1996).

Exercise

Exercise is a critical component to maintaining the health of bone tissue (Spirduso et al, 2005). In particular, weight-bearing and loading activities are essential for bone formation and the increase and maintenance of BMD (Spirduso et al, 2005). Regular weight-bearing activities combined with a consistent exercise routine are key components of optimal bone health for all ages, particularly older adult populations ( Bloomfield, 2005). Many studies have been have been performed on the effects of immobilization, paralysis, and disuse of muscle tissue. Much of the knowledge about humans exposed to long periods of inactivity comes from studies done on humans in space flight ( Bloomfield, 2005). The majority of these studies have observed that under these conditions, there is a rapid loss of BMD and an increase in the risk of fractures ( Bloomfield, 2005). Age related bone loss begins to occur between the ages of 35 or 40 ( Bloomfield, 2005). As a result, exercise interventions targeted at the middle aged and older adult populations must shift from the notion of increasing peak bone mass, to minimizing the loss, and preserving bone mass (Bloomfield, 2005). As with all chronic diseases the most effective strategies are those that are initiated at an early age. Individuals engaging in physical activity from an early age and throughout young adulthood are able to achieve higher levels of peak bone mass, and thus delay the onset of symptoms related to osteoporosis ( Bloomfield, 2005). It has also been reported that individuals who are physically active in their youth tend to remain active during middle age and older adulthood, thus aiding in the preservation of bone mass ( Bloomfield, 2005). Many older adults report decreased levels of physical activity (Pfeifer et al, 2004). A variety of reasons have been cited to help explain this trend; among these include a lack of available facilities, fear of injury, and complications due to coexisting chronic conditions (Pfeifer et al, 2004). Many older adults commented that their surrounding environment was not conducive to engaging in physical activity due to a lack of parks and open space, as well as the absence of sidewalks and pathways (Pfeifer et al, 2004). Older adults also indicated that their primary healthcare providers discouraged participating in physical activity due to the risk of injury (Pfeifer et al, 2004). Finally, studies indicate that there appears to be a lack of knowledge amongst older adults with respect to the potential benefits of physical activity in preventing osteoporosis and hip fractures (Bogoch, 2006). Health practitioners are often hesitant to prescribe an exercise regimen to older adult patients in an attempt to reduce the risk of osteoporosis and hip fractures. A growing body of scientific knowledge is changing the way healthcare addresses the exercise needs of the older adult population, and is acknowledging the many observed benefits of physical activity in the older adult populations. A study analyzing osteoporosis prevention strategies found that regular exercise, specifically resistance training and high-impact activities helped contribute to the development of higher levels of peak bone mass and was found to reduce the risk of falls in older adults (Anonymous, 2000). A further study investigating non-pharmacological interventions for treating osteoporosis observed that elderly people who engaged in physical activity, and home rehabilitation programs that incorporated exercise as a part of their regiment, helped to prevent the re-occurrence of falls (Beaudreuil, 2006). This same study found that physical exercise and rehabilitation have been consistently shown to be effective interventions in preventing falls in older adults (Beaudreuil, 2006). Another study investigated the effects of resistance training on bone mass in a group of post-menopausal women. BMD was measured every six months. Towards the end of the two-year intervention period, the study found that there was a significant increase in BMD at the forearm, lumbar spine, and intertrochanter hip sites (Kerr, Ackland, Maslen, Morton, & Prince, 2001). This study concluded that a progressive strength program is an effective strategy to increase bone density at clinically important hip sites, and that a strength program could be utilized as a preventative strategy to osteoporosis treatment as primary method, or in conjunction with another treatment (Kerr et al, 2001). Another study conducted a literary review of the effects of weighted exercise on bone mineral density in postmenopausal women. This review revealed that weight-training exercises were an effective method to increase BMD in postmenopausal women (Zehnacker & Bemis-Dougherty, 2007). This same study found that the increases in BMD were “site specific and required high loading with a training intensity of 70% to 90% of 1RM for 8 to 12 repetitions of 2 to 3 sets performed over one year duration” (Zehnacker & Bemis-Dougherty, 2007, p. 85). The authors of this study concluded that weighted exercise regiments can help maintain BMD in post-menopausal women and can increase BMD in the spine and hip (Zehnacker & Bemis-Dougherty, 2007). The authors emphasized that “The exercise program must be incorporated into a lifestyle change and be lifelong due to the chronic nature of bone loss in older women” (Zehnacker & Bemis-Dougherty, 2007, p. 88). This study commented that osteoporosis is preventable and treatable, with exercise playing and important and effective role in the generation and maintenance of bone tissue (Zehnacker & Bemis-Dougherty, 2007). Another study examining the effects of musculoskeletal rehabilitation in osteoporosis found that implementing individually tailored exercise programs have been an effective measure in reducing falls, and fall-related injuries (Pfeifer et al, 2004). The authors of this study found that the exercise programs provide several benefits and protective properties, which include, strengthening of the paraspinal muscles, maintaining BMD, and reducing the risk of vertebral fractures (Pfeifer et al, 2004). This particular study observed that a rehabilitation regimen should include elements of proprioceptive dynamic posture training in order to decrease kyphotic posturing through recruitment of back extensors resulting in a reduction of pain and improving mobility, with the cumulative effect of improving the overall quality of life (Pfeifer et al, 2004). This particular study also highlighted the use of a newly developed orthosis designed to increase back extensor strength and decrease body sway, both of which have been identified as risk factors for increasing the frequency of falls and fall related fractures (Pfeifer et al, 2004). This study also highlighted the use of hip protectors in conjunction with and exercise regimen as a method of preventing hip fractures and increasing the strength and mobility of hip muscles (Pfeifer et al, 2004). A further study examined the effects of physical activity on the risk of falls and fractures in older adults. The study design used randomized controlled trials and found that exercise that incorporated balance and lower extremity strength training reduced the risk of falls in older adults (Gregg, Pereira, & Caspersen, 2000). This same study found that engaging in physical activity resulted in a 20-40% decrease in the risk of hip fractures when compared to sedentary individuals (Gregg, Pereira, & Caspersen, 2000). The authors of this study concluded that increased levels of leisure time activity as well as the implementation of exercise programs can reduce the risks of falls and prevent hip fractures (Gregg, Pereira, & Caspersen, 2000). Many investigative studies have concluded that weight bearing exercises in the form of resistance training with components of flexibility and balance are effective measures in maintaining BMD, reducing the incidence of falls and fractures, and finally preventing and mitigating osteoporosis (Hingorjo, Syed, & Qureshi, 2008). When designing an exercise program for older adults who are at risk of developing, or with existing osteoporosis, it is imperative to avoid activities requiring forward flexion of the spine, especially when lifting weights from the floor, as this can result in an increase in vertebral fractures. Importance must be placed on providing a safe and well-monitored exercise and training regiment for older adults ( Bloomfield, 2005). This task is indeed manageable and could have a significant impact on the physical independence of this particular high-risk population ( Bloomfield, 2005).

Screening Practices and Primary Care Education

In recent years the major complication in treating osteoporosis has shifted. Osteoporosis is a chronic condition that can be effectively managed. However, osteoporosis remains under-treated due to inadequate screening and diagnostic procedures (Singer, 2006). Despite advancements in diagnostic imaging and an ever-increasing medical knowledge base with respect to symptoms and treatments of osteoporosis, more than two thirds of older adults remained undiagnosed after sustaining a fracture and less than one third were prescribed adequate therapy (Singer, 2006). A study looking at methods to improve osteoporosis treatment rates among elderly patients discovered that missed opportunities for the diagnosis and treatment of osteoporosis following the onset of a fracture was increasingly common in the elderly (Nadrash, Plushner, & Delate, 2008). A study attempting to improve osteoporosis management in patients with fractures discovered that a prior history of fractures is an independent risk factor for the development and occurrence of future fractures (Johnson, Petkov, Williams, Vias, & Adler, 2005). Remarkably though, patients who had sustained a fracture were rarely evaluated or screened for osteoporosis by their physician or other primary healthcare worker (Johnson et al, 2005). This particular lapse in judgment is fairly alarming, and should serve as a warning to the healthcare community. The World Health Organization (WHO) has established a series of criteria based on BMD measurements in order to identify individuals who are at risk of developing osteoporosis (Singer, 2006). One diagnostic imaging method that has emerged as the gold standard is dual-energy x-ray absorptiometry (DXA) (El Maghraoui & Roux, 2008). DXA has been established as a reliable reference method of measuring bone mineral density (El Maghraoui & Roux, 2008). The National Osteoporosis Foundation (NOF) along with the WHO have established protocols and guidelines outlining which particular patients should be screened for osteoporosis (Singer, 2006). These include postmenopausal women, and adults aged 65 and older (Singer, 2006). However, a large number of osteoporotic fractures occur in patients outside of the mentioned groups (Singer, 2006). Thus a large group of patients are never screened (Singer, 2006). A further point made by the same author is that DXA technology is costly and is not always available in healthcare centers (Singer, 2006). As a result, public screening for osteoporosis across population groups can become difficult and impractical (Singer, 2006). Much of the research has yet to address this particular issue, and there is but a handful of feasible options. One particular solution to screening deficiencies is “case-finding” (Singer, 2006). Case-finding is the process whereby easily identifiable and highly prevalent risk factors in the population are used to identify potential candidates for BMD testing (Singer, 2006). Examples of these factors include body weight and body mass index, which have been shown to have significant correlation with BMD (Singer, 2006). The above mentioned parameters are easily measured and can be used as markers for BMD (Singer, 2006). Early detection of osteoporosis and osteoporotic fractures through effective screening processes are critical in reducing the incidence vertebral and non-vertebral fractures (Singer, 2006).

Coupled with appropriate screening practices it is important to increase primary care education for managing patients with osteoporosis (Simonelli, Killeen, Mehle, & Swanson, 2002). A study was conducted that investigated the barriers to osteoporosis identification and treatment among primary care physicians and orthopedic surgeons. Findings indicated that post-fracture care was principally the responsibility of the primary care provider (Simonelli et al, 2002). With respect to the topic of testing for bone density using DXA, 39% of physicians thought this type of treatment was unnecessary, while 17% of physicians cited patient frailty as the primary barrier to bone density screening (Simonelli et al, 2002). Cost was also a limiting factor, as 61% of physicians interviewed quoted the significant expense of DXA imaging as the greatest deterrent (Simonelli et al, 2002). This same study found that 70% of primary care physicians, and 50% of orthopedic surgeons agreed that there is a need for increased primary care education with respect to managing patients with osteoporosis and low-impact fractures (Simonelli, 2002). In 2005 the American Orthopaedic Association conducted a project titled “Own the Bone” (Tosi, Gliklich, Kannan, & Koval, 2008). The primary purpose of this project was to provide physicians with the tools to prevent secondary fractures and to increase screening practices for patients at risk of developing osteoporosis (Tosi et al, 2008). The results of this study indicated that although there was a marked improvement in patient counseling on calcium and vitamin D supplementation, exercise, fall prevention, and communication between patients and primary care providers, there was no significant improvement in physicians ordering bone mineral density testing (Tosi et al, 2008). The importance of bone density screening practices and primary care education cannot be overlooked. A study examining the osteoporosis management in primary care found that DXA scans were effective in identifying patients with prior hip fractures and those with osteoporosis (Brankin, Mitchell, & Munro, 2005). The authors of this study also found that disease management programmes in primary care to identify high risk patients and ensure appropriate prescribing would have numerous benefits, including being pharmaco-economically prudent as well as improve management of patients with fragility fractures (Brankin et al, 2005).

Conclusion

Osteoporosis is a chronic disease that has impacts on a variety of dimensions of health, and can negatively impact an older adults quality of life. The purpose of this analysis was to examine preventative practices that can be used to counteract and mitigate the debilitating effects of decreasing bone mineral density in older adults leading to osteoporosis and increasing the incidence of hip fractures. Proper nutrition provides the foundation for the maintenance and growth of bone tissue, specifically adequate dietary intakes of calcium and vitamin D to abate bone loss and to increase and maintain bone mineral density. Exercise is a component that is often overlooked by primary healthcare providers due to fear of injury and further complications. Much research has shown that weight-bearing activities can be an effective strategy in preventing the onset of osteoporosis and increasing bone mineral density. Furthermore, exercise is an excellent rehabilitative tool, and should incorporate elements of balance and resistance training in order to achieve optimal benefits. Finally, appropriate screening practices and increasing education about managing patients with osteoporosis and hip fractures is critical. DXA screens can be an accurate and effective method for detecting the onset of osteoporosis. However cost and availability often prevent public screening. Additionally physician education and disease management programs can be an effective measure in reducing the incidence and health costs related to osteoporosis and osteoporotic fractures.

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