Helen, a 62-year-old, thin, postmenopausal woman with a history of hypothyroidism and asthma, arrives for a routine annual gynecological exam. She admits to her nurse that she doesn’t exercise regularly, and her diet does not meet recommended daily calcium requirements. On exam, the nurse notices that Helen has developed upper torso curving. A subsequent bone density test confirms that she is in the early stage of osteoporosis.

Osteoporosis is a skeletal disorder characterized by compromised bone strength, predisposing to an increased risk of fracture. The disease occurs when the rate of bone resorption is greater than the rate of bone formation. As bone mass diminishes, bones become fragile, raising the risk of fractures from even minimal trauma.^1,2 One study placed the annual estimated cost of 1.5 million fractures as high as $17 billion³ and rising. In fact, the National Center for Injury Prevention and Control has projected that cost could escalate to $240 billion by the year 2040.⁴

More than 10 million women and men in the U.S. have osteoporosis, and 34 million more have low bone mass, placing them at increased risk for this disease.⁵ Although osteoporosis strikes more women than men, both men and women lose bone mass at approximately the same rate by age 65 or 70. According to the National Osteoporosis Foundation, one in two women and one in eight men over the age of 50 in the U.S. will suffer an osteoporosis-related fracture in their lifetime. As the median age of the population in the U.S. increases, osteoporosis will become a major health concern in almost every setting in which nurses work.⁶

Losing Bone

The human skeleton contains 206 bones, which contain various percentages of cortical (compact) and trabecular (cancellous) bone. Cortical bone is densely packed and comprises the exterior of bones. Trabecular bone is spongy, similar to cortical in chemical composition and ultrastructure, and found in the distal radius, hip, and vertebra. Metabolism and remodeling occur at higher rates in trabecular bone. Bones with a greater percentage of trabecullar bone are most likely to suffer osteoporotic fractures. Although trabecular bone accounts for only 15% of the skeleton, it is the site where the most demineralization occurs.¹

Bone is a metabolically active organ that undergoes constant structural change from osteoclasts and osteoblasts found in the marrow. Endocrine glands regulate bone reconstruction by signaling osteoclasts to break down bone and osteoblasts to rebuild it. Genetic and environmental factors as well as the amount of calcium available in the body also influence bone formation. When there is insufficient calcium to supply major organs, such as the heart, nerves, and muscles, osteoclasts release calcium from the bones, leaving minute gaps that lower bone density.⁶

The Effects of Age on Bone Mass

During childhood, increased bone production strengthens and augments the skeleton. In adolescence, the lengthwise growth of bones stops, while the bone density and strength continue to increase. Peak bone mass is achieved for the interior bone tissue, or trabecular bone, by the early 20s. Cortical bone reaches its peak mass several years later. Throughout young adulthood, a remodeling process of bone resorption and formation ensures that bones fundamentally remain the same. In fact, before a person’s mid-30s, more new bone is gained than lost. However, after the mid-30s, the balance between breaking down old bone and building new bone is disrupted. Once menopause occurs, a lack of estrogen increases bone resorption and decreases calcium absorption, resulting in bone loss and a corresponding reduction in bone mass.² In the first five to 10 years after menopause, bone loss is about 2% to 3% per year, tapering off to 0.3% to 1% yearly. By the age of 80, a woman could lose up to 30% of her bone mass.¹

The bone thinning of osteoporosis increases the risk of fractures. Osteoporotic fractures most commonly occur in the vertebrae, the femur, and the radius. Hormonal changes of menopause affect the trabecular portions of the vertebrae and distal wrist the most, putting them at a greater risk for fractures. Fractures can significantly affect the elderly, causing chronic pain, disability, postural changes and, in some cases, requiring extensive physical therapy and assistance with daily activities. Hip fractures — the most serious of the osteoporotic fractures — generally require surgical intervention, physical therapy, and often, admission to a chronic care facility. According to the 2004 Surgeon General’s Report, 180,000 patients were placed in chronic care facilities due to osteoporotic fractures. Fewer than half of the hospitalized hip fracture patients recover to their prefracture ability to manage their everyday lives.⁷ The first year after these injuries is characterized by 12% to 24% mortality, which may be caused by complications or prolonged immobilization.¹

Characteristic Findings in Osteoporosis

Due to an absence of early symptoms, osteoporosis has been labeled a “silent disease.” At the same time, people may overlook symptoms of back pain, height loss, weak extremities, and kyphosis that reflect an advanced stage of the disease. Many women have osteoporosis for years without realizing it until a bone fracture occurs. A fractured bone after the age of 50 could indicate the first sign of osteoporosis.¹ In advanced cases, simply coughing, lifting groceries, or standing too long may produce a compression fracture.⁸

Once vertebrae are fractured, a person’s normal anatomical position is changed. The upper portion of the back assumes a forward-bending curvature called the dowager’s hump, which causes a loss of stature. As demineralization continues, the waistline disappears and the abdomen protrudes.⁶ A drastically curved spine can produce chronic neck and back pain. Dyspnea can occur from the crowding of internal organs and interference with chest expansion. In severe cases, the ribs will rest on the pelvic bones.

Diagnostic Tests and Evaluation

Although an accurate and early diagnosis is essential for halting further bone destruction, osteoporosis is rarely diagnosed before advanced bone loss occurs. Osteoporosis is so difficult to detect that it may not show up by x-ray until bone loss of 30% or greater has occurred. Many times healthcare providers only accidentally discover the disease while examining x-rays taken for some other medical condition, such as chronic back pain, height loss, a curving spine, or a fractured bone.⁹

Assessment of medical history, risk factors, the patient’s lifestyle, and family history can help determine the risk of osteoporosis. However, conditions that mimic osteoporosis also need to be ruled out. For example, degenerative arthritis, disc disease, and osteomalacia — conditions that involve loss of calcium and other minerals from the bones — are associated with symptoms of low back pain and loss of bone mass similar to osteoporosis. Patients should have urine and blood tests, including a complete blood cell count and thyrotropin level, because excessive serum thyroid-stimulating hormone can accelerate bone loss. Due to its important role in calcium absorption and bone integrity, vitamin D deficiency should be ruled out. Vitamin D production slows in the elderly, the housebound, and those subjected to long periods of cloudy weather, because it is synthesized through sun exposure.²

Bone mineral density (BMD) and skeletal imaging studies are the primary diagnostic tools for osteoporosis. Bone density refers to the amount of mineral contained in a specific bone and therefore the relative strength of the bone. The precise measurements of bone densitometry can identify fracture risks, indicate candidates for intervention, and initial therapy for osteoporosis. However, subsequent changes in BMD are an imperfect indicator of the efficacy of treatment.¹⁰ Nevertheless, nurses can be instrumental in preventing or halting osteoporosis and its sequelae by educating patients about the BMD test, as well as osteoporosis, its risk factors, and fall prevention.

Specific tests can evaluate the risk or detect progress of osteoporosis.^2,11,12

• Dual Energy X-ray Absorptiometry (DXA), which uses x-rays without radioactive isotopes to estimate the bone mass of the entire skeleton, is the single most important test to confirm the diagnosis of osteoporosis. DXA measurements are typically taken of the lumbar spine and femoral neck. Peripheral DXA (pDXA) measures BMD at the wrist or heel.
• Quantitative Computed Tomography (QCT) measures the amount of trabecular bone inside the vertebrae. Although precise, the QCT uses more radiation, time, and money; the peripheral version (pQCT) is also accurate, though less costly, and measures BMD of the forearm.
• Quantitative Ultrasound (QUS) is a new, noninvasive method that measures bone density of the heel and provides information about the structure and mechanical properties of bone. QUS has advantages of low cost, portability, speed (five minutes), and nonionizing radiation. However, it is a screening, not a diagnostic tool.
• Biochemical markers, revealed in blood and urine tests, can assess bone disease. In conjunction with densitometry measurements, they can determine the rate of bone turnover and evaluate the efficacy of therapy.

Osteoporosis irreversibly damages bone tissue. Therefore, therapy strives to prevent further degeneration and to correct underlying medical conditions that cause bone demineralization.

Hormone Therapy (HT), particularly the use of estrogen, is one of the most effective measures for halting osteoporosis. Estrogen can prevent 50% to 60% of the fractures associated with osteoporosis.^13,14 Estrogen therapy prevents bone loss and fractures, relieves vasomotor symptoms (hot flashes), and protects against urogenital atrophy. Among the adverse effects of estrogen replacement is the risk of endometrial hyperplasia. Due to endometrial carcinoma risk, the American College of Obstetrics and Gynecology recommends a combination of estrogen and progestin for women who have a uterus. Adding progestin reduces the risk of endometrial cancer and enhances the bone-protecting qualities of estrogen. Progestin may cause irregular vaginal bleeding, adverse mood changes, and lower HDL levels.

Currently, HT is indicated for prevention, not treatment, of osteoporosis. And given the results of the recent Women’s Health Initiative study, it should only be used in women who are also experiencing vasomotor symptoms that disrupt their quality of life.

Biphosphonates were approved by the Food and Drug Administration (FDA) in 1995 for treatment and in 1997 for prevention of osteoporosis.² These agents halt the progression of the disease by inhibiting the resorptive activity of osteoclasts without injuring them. Alendronate (Fosamax), a third-generation biphosphonate, has demonstrated reductions of 47% in the risk of developing vertebral fracture, 44% in distal radius fractures, and 51% in hip fractures,^5,15 as well as a decrease in the progression of vertebral deformities and loss of height.¹⁶ Risedronate (Actonel) is a new biphosphonate with promising results. It reduced the risk of hip fracture by 58% over three years in elderly women with low femoral neck BMD in the hip and existing spine fractures. Alendronate and risedronate are administered on a daily or weekly basis. Ibandronate (Boniva) is a new bisphosphonate approved by the FDA as a once-a-month pill to treat and prevent osteoporosis. Studies have shown that ibandronate increased the BMD in vertebrae and hips, as well as decreased the rate of bone turnover.¹⁷

Patient education regarding biphosphonates is essential to increase adherence. Biphosphonates are absorbed poorly from the GI tract and should be taken, preferably upon waking, on an empty stomach with a full glass of water to improve bioavailability. For 30 minutes after ingestion, the patient should remain in an upright position to prevent esophageal reflux and refrain from eating and taking calcium supplements and antacids, which interfere with the absorption of bisphosphonates for at least 30 minutes. Abdominal pain, dyspepsia, nausea, constipation, diarrhea, flatulence, esophageal ulceration, musculoskeletal pain, and headache are reported adverse effects.^6,15

Calcitonin is a hormone secreted by the thyroid in response to increased calcium in the blood. With aging, the calcitonin level decreases and is less effective at inhibiting osteoclastic-mediated bone resorption.⁹ Calcitonin is indicated for treatment in postmenopausal women who are unable to use HT. As a medication, calcitonin cannot be taken orally and must be administered parenterally or via a nasal spray preparation. A recent five-year study of 1,200 women with osteoporosis who had previous spinal fractures demonstrated that calcitonin (Miacalcin) nasal spray reduced the incidence of new spinal fractures by 36%.¹⁸ In injectable form, calcitonin is an effective analgesic therapy for pain from acute and chronic osteoporotic vertebral fractures.

Minor adverse effects associated with calcitonin include nausea, vertigo, tingling of the hands, and facial flushing. The gastrointestinal (GI) and flushing effects are eliminated with the nasal spray, but irritation of the nasal mucosa may occur. Supplemental calcium and a multiple vitamin must be taken to prevent a rebound hyperparathyroidism.^1,2

Selected estrogen receptor modulators (SERMs) are a new category of therapeutic agents that mimic estrogen in some tissues and act as estrogen antagonists in others. Approved in 1997 by the FDA for the prevention of osteoporosis, raloxifene (Evista) is a second-generation SERM. Raloxifene is an alternative to HRT for women who are medically unable or choose not to take estrogen. Although not as effective as estrogen, the drug can reduce the risk of vertebral fractures by 36% with an added benefit of reducing serum cholesterol and lowering the risk of myocardial infarction.¹⁹ Unlike estrogen, raloxifene does not cause monthly bleeding, water retention, or breast tenderness. Adverse effects include venous thrombosis, hot flashes, and leg cramps. In clinical trials, raloxifene has not been associated with an increased risk of endometrial or breast cancer. Current studies are focused on the effect of raloxifene on the prevention of breast cancer due to its estrogen antagonism of breast tissue.^20,21

Parathyroid hormone (PTH) in the injectable form is approved for the treatment of osteoporosis in postmenopausal women and men who are at extremely high risks for having a fracture. Unlike other available treatments that reduce the activity of osteoclasts, PTH actually increases the bone-building of osteoblasts. PTH studies found the vertebrae increased in size as well as bone density. This is a significant advance in the prevention of fractures by ensuring stronger bones that are bigger and more resistant to fractures. Postmenopausal women in the study decreased the risk of vertebral fractures by about 65% and nonvertebral fractures by 54%. PTH (teriparatide) provides an option for those unresponsive or unable to tolerate the side effects of other agents.^22,23,24

Kyphoplasty Revolutionizes Vertebral Fracture Treatment

Research indicates that kyphoplasty is making significant progress in the treatment of pain associated with osteoporotic vertebral fractures. Kyphoplasty is a minimally invasive procedure that involves inserting an orthopedic balloon into the fractured vertebra; inflating the balloon causes fractured bone fragments to elevate, thus restoring vertebral anatomy. Next, the balloon is removed and the vertebral cavity is filled with methylmethacrylate bone cement. Kyphoplasty has been shown to provide a 96% pain relief from an acute vertebral compression fracture. Kyphoplasty restored body height to 45% (anterior), 71% (midline), and 54% (posterior).

Although kyphoplasty may reduce or relieve the pain associated with a vertebral fracture as well as correct the spinal deformity, kyphoplasty is not indicated for all vertebral fractures. It is performed if the fracture causes intractable pain that is unresponsive to analgesics and rest, and if the fracture is acute, rather than healed. The procedure may also be beneficial if there are negative consequences associated with the vertebral fracture deformity. Significant height loss may diminish the vital capacity in patients with pulmonary disease. Serious complications associated with the procedure include spinal cord compression.^6,25,26

A Bone-Saving, Preventative Triad

Calcium, vitamin D, and exercise are traditional weapons in the fight against osteoporosis. Although they will not halt the bone resorption that occurs with osteoporosis, they are essential adjuncts to the medical regimen or preventative measures for those at risk.

Adults over 65 typically take less than 600 mg/day of calcium, which is inadequate to maintain bone integrity.²⁵ The Institute of Medicine advises women and men to have a daily calcium intake of 1,000 mg/day until age 50 and 1,200 mg/day over age 50. Women who are on HRT need at least 1,000 mg/day of calcium, while postmenopausal women not taking HRT require 1,500 mg/day. Adolescent, pregnant, and breastfeeding women need 1,200 mg/day of calcium. If a diet is deficient in calcium, supplements should be added,²⁷ although the preferred source of calcium is dietary.

Vitamin D is integral in calcium absorption and bone metabolism. Adequate levels of vitamin D can be obtained from sunlight, diet, or vitamin supplementation. Usual daily requirements are 200 IU for premenopausal women, 400 to 800 IU for postmenopausal women, and 400 IU for men over age 65.²

A regular routine of weight-bearing exercises in which bones and muscles work against gravity is another important aspect of prevention. This type of exercise puts stress on long bones to augment their mass and improves agility and balance. A complete osteoporosis exercise prevention program also includes isometric strength training. Finally, lifestyle adjustments, such as quitting smoking, reducing alcohol consumption, and maintaining appropriate body weight, can help preserve bone mass and prevent osteoporosis.

What Nurses Can Do

Nurses can help patients reduce the risk of developing osteoporosis during their life cycle. They need to encourage families to adopt activities and healthy habits, such as regular exercise and a proper diet, that maximize bone density, especially during the peak bone growth that takes place during childhood, adolescence, and young adulthood. Nurses can also assist patients to understand and prevent this devastating disease through early identification and evaluation of those at risk, the provision of information to reduce risk factors, and guidance and support for patients to practice healthy lifestyle habits. Education regarding medications prescribed to prevent further bone loss is crucial to ensure patient adherence. Home care nurses have a special opportunity to prevent falls and potential fractures by evaluating their patients’ use of sedatives, identifying sensory deficits, and assisting patients in making their homes safe environments.

With new treatment modalities aimed at prevention, more research is needed to develop criteria to identify those at risk who would benefit from bone density screening studies and early intervention to avoid this costly and debilitating disease. Osteoporosis does not have to be an inevitable part of the aging process.

Along with weight-training, Helen begins an intensive walking program and a diet supplemented with calcium and vitamin D. She declines HRT because of her fears of cancer. She initially takes a prescribed 10 mg daily dose of alendronate, but discontinues the medication after experiencing GI distress. She is now taking 200 mg of raloxifene every day with a follow-up BMD test in one year.