Osteoporosis is a complex, multifactorial disease of compromised bone strength and integrity. When we look at bone strength we’re essentially looking at two things – the quality of the bone and the bone mass. Essentially, what is occurring in osteoporosis is accelerated bone resorption along with decreased bone formation. As this process continues and the disease progresses, the bones become porous, brittle and more prone to breaking.

Endocrine Review

To fully understand osteoporosis, let’s take a quick detour to review the relevant hormones and their role in bone formation and resorption. 

  • Estrogen – Estrogen is bone protective and plays an important role in the formation of healthy bone. Estrogen acts on the osteoclasts to prevent bones from breaking down, and it acts on the osteoblasts to help stimulate the formation of new bone. 
  • Testosterone – Testosterone plays an important role in bone density, and lower testosterone levels leads to bone loss.
  • Parathyroid hormone (PTH) – PTH is interesting because its effect on bone is dependent upon how it is administered. When given continuously, PTH causes bone resorption and bone loss. However, when it is given intermittently, PTH causes bone formation. This will come into play when we talk about pharmacologic treatments for osteoporosis. In general PTH enhances the release of calcium from bones and thereby stimulates bone resorption and decreases the formation of new bone. 
  • Thyroid hormones – Hyperthyroidism leads to high bone turnover with reduced remodeling time, leading to a loss of bone mass.
  • Cortisol – Elevated cortisol levels inhibit osteoblast function which leads to less bone formation and weaker bones.

Types of Osteoporosis

There are two main types of osteoporosis. Primary osteoporosis, which is the most common type, and secondary osteoporosis, which is osteoporosis caused by another condition such as hyperthyroidism or medications. There are two main subtypes of primary osteoporosis. 

Type 1: Postmenopausal osteoporosis usually affects women who have gone through menopause and is related to a loss of estrogen. Recall that estrogen has a protective effect on bone. This type of osteoporosis affects trabecular (spongy) bone more than it does the hard, cortical bone. It is often related to wrist fractures and then later by vertebral fractures as the individual ages.

Type 2: Senile osteoporosis occurs in older individuals, namely age 70-85. It tends to be related to the loss of both trabecular (spongy) and cortical (hard) bone and is associated with aging. It is common to see vertebral, leg and pelvis fractures with senile osteoporosis. 

Osteoporosis for nursing studentsThe development of osteoporosis is also related to many potential factors both modifiable and non-modifiable:

  • Non-modifiable risk factors are female gender, White/Asian race, family history of osteoporosis, advanced age, fair skinned, early menopause, late menarche and small stature.
  • Dietary risk factors include deficiencies in calcium, magnesium and vitamin D. Diets high in protein and sodium contribute to bone loss as does high caffeine intake.
  • Malabsorption plays a role in bone loss. It can be a result of bariatric surgery, celiac disease, and anorexia.
  • Underlying disease conditions that contribute to osteoporosis are renal insufficiency, bone marrow disorders, rheumatoid arthritis, systemic lupus erythematosus, liver disease, Cushing’s disease, hyperthyroidism and hyperparathyroidism.
  • Individuals taking certain medications such as phenytoin, phenobarbital, corticosteroids, heparin, progestins, loop diuretics, warfarin, methotrexate, cyclosporine, thyroid hormone and aluminum-containing antacids. You may see lithium indicated as a contributor to osteoporosis, but other studies suggest it does not play a role. 
  • Though the relationship remains unclear, there is some evidence that PPIs contribute to osteoporosis through malabsorption secondary to hypochlorhydria among other factors. This review of the literature dives into this complex topic if you’d like to explore it further.
  • Men who receive androgen deprivation therapy as a treatment for prostate cancer are at higher risk for osteoporosis.
  • Lifestyle factors that contribute are lack of exercise, smoking and excessive alcohol use.

What are the complications of osteoporosis?

The most serious complication of osteoporosis is fracture. Depending on the individual’s age and health status, a hip or spinal fracture can cause severe disability and even lead to the individual’s death within a year of injury. It’s important to note that a fall or trauma is not always  necessary for a fracture to occur. If the osteoporosis is severe, fractures can occur spontaneously. 

Osteoporotic fractures are also a significant contributor to health care costs which are estimated to be $20 billion per year. Additionally the risk of death from complications associated with hip fracture is close to 25% in the first year following the fracture. Over 50% of patients who suffer a hip fracture have mobility issues that affect them for the rest of their lives, and 25% of them must go into long-term care.

Now that you have a general understanding of osteoporosis, let’s go through the key things you need to know for your exams using the Straight A Nursing LATTE method.

L: How does the patient LOOK? 

The patient with osteoporosis may have no outward signs or noticeable symptoms until severe disease or fracture is present. Some common signs and symptoms are:

  • Complaints of back pain, which is caused by either a vertebral fracture or collapsed vertebra. A vertebral fracture is the most common manifestation of osteoporosis and while they can cause pain, they are often found incidentally when a chest or abdominal x-ray is taken. 
  • The individual may have a stooped posture and loss of height over time.
  • If a fracture is present, the patient will likely complain of pain.
  • The patient will not be able to bear weight on a fractured hip. Note that hip fractures occur in up to 15% of women and 5% of men by age 80.
  • Some fractures may cause a bony prominence which can be visualized or palpated.

A: How do you ASSESS the patient with osteoporosis?

General assessment of a patient with osteoporosis will often be related to a fracture as that is when many individuals first seek treatment. Carefully assess the patient for signs of physical trauma that could explain any pain the patient is experiencing such as bruising or injury elsewhere in the body. If the patient is complaining of pain or diminished mobility, assess for circulation, sensation and movement (CSM) of the affected limb/area of the body. 

In addition, other assessments may include: 

  • Assess for pain including onset, severity and provoking factors
  • Assess for osteoporosis risk factors and culprit medications as outlined above
  • Measure the patient’s height and compare to earlier measurements
  • Assess for fall risk and fall hazards in the home and in-patient setting

T: What TESTS will be conducted for an individual with osteoporosis?

Osteoporosis can be diagnosed simply due to the presence of a fragility fracture, which is a fracture that either occurs spontaneously or due to minor trauma. The most common sites of a fragility fracture are the wrist, hip and spine. 

The key diagnostic tests for osteoporosis are:

  • Bone mineral density (BMD) – Bone mineral density can be assessed by DXA which is the standard test for diagnosing osteoporosis. The result is a “T-score” which compares the individual’s bone mineral density against a young adult reference. A T-score 2.5 or more standard deviations below the young adult reference score is considered osteoporosis. Individuals with a T-score at or above 2.5 have the highest risk of bone fracture. It is recommended that BMD measurements be taken at the lumbar spine and neck of the upper femur as fractures in these areas have the greatest impact on a patient’s overall health and mobility.
  • Quantitative computerized tomography (QCT) – This test measures the patient’s BMD using a CT scan and is most often used when assessing the spine or femur just below the hip.
  • Peripheral densitometers – These portable devices can measure bone density at the periphery of the skeleton, most often the wrist and heel. A positive test with one of these devices will typically indicate a more thorough follow-up scan is warranted.
  • Though not technically a diagnostic test, the Z-score compares the patient’s BMD against an age-matched population and is more often used in younger individuals. A Z-score of -2 or lower is considered to be higher risk for osteoporosis when compared to others of the same age.
  • FRAX is the Fracture Risk Assessment Tool. This computer-based calculator assesses a patient’s 10-year risk of a major osteoporotic fracture (hip, humerus, or spine) and can be done with or without a BMD score. 
  • Blood tests will measure levels of calcium, phosphorus, total protein, vitamin D, thyroid hormone, parathyroid hormone, liver enzymes, cortisol, and other key factors that contribute to bone health and density.

T: What TREATMENTS will be provided?

One of the first treatments for osteoporosis will be addressing modifiable risk factors:

  • Promote exercise, especially weight-bearing exercise.
  • Encourage smoking cessation and avoidance of heavy alcohol use.

Medications used in the treatment of osteoporosis:

  • Hormone replacement therapy has been shown to decrease incidence of vertebral fracture
    • Raloxifene (Evista) is a selective estrogen receptor modulator or SERM. This medication is used to reduce the resorption of bone and has been shown to decrease the risk of vertebral fracture by 30-50%.  Adverse effects are hot flashes, increased risk for thromboembolism, and increased risk for uterine cancer.
    • Women taking hormone replacement therapy with estrogen or estrogen-progestin combination therapy do have reduced risk of hip and vertebral fracture. Note that estrogen therapy is FDA approved for prevention but not treatment of osteoporosis. General recommendations are that it is not first-line therapy and should be used for the shortest duration possible because of adverse effects including increased risk of coronary heart disease, stroke, thromboembolism and breast cancer.
  • Bisphosphonates are typically considered first-line therapy. These medications inhibit osteoclastic activity and reduce bone resorption. The most significant side effects for bisphosphonates are GI related, though there is also evidence that links these medications to increased risk for atrial fibrillation, especially when using the IV formulations. Two common bisphosphonates are alendronate (Fosamax) and risedronate (Actonel). 
  • Anabolic agents such as teriparatide (Forteo) and abaloparatide (Tymlos) are similar to parathyroid hormone and are utilized to stimulate bone formation in individuals at high risk for fracture. It is only used for a two-year period and cannot be utilized by anyone with Paget’s disease, patients who have received beam or implanted skeletal radiation or have a history of bone metastasis. A newer anabolic agent is romosozumab (Evenity), which is administered monthly via injection and can be taken for only one year.
  • Denosumab (Prolia) is a monoclonal antibody that inhibits osteoclasts and is typically only used in those who do not benefit from bisphosphonate therapy or have cancer with bone metastasis. This medication is given via subcutaneous injection every six months and has been shown to reduce vertebral and hip fractures significantly though it does not come without a price. Adverse effects can include increased incidence of sepsis, osteonecrosis of the jaw and musculoskeletal pain.
  • Calcium and Vitamin D supplementation are inexpensive pharmacologic treatments. These supplements should be taken together as vitamin D helps improve the uptake of calcium. Calcium carbonate (Tums) has the most elemental calcium per dose (and is inexpensive), but calcium citrate may be better absorbed, especially by those taking an acid-reducing medication.

E: How do you EDUCATE the patient who has osteoporosis?

Key teaching for a patient with osteoporosis will center on reducing risk of fracture and improving bone health through lifestyle modification and pharmacologic adherence. 

  • At-risk patients should be educated on things they can do to reduce risk such as smoking cessation and avoiding excessive alcohol use.
  • Begin or continue to take calcium and vitamin D supplements as advised by their physician or nurse practitioner.
  • Teach the patient to avoid risky activities and sports as well as fall prevention strategies. The CDC has excellent resources for fall prevention such as this one.
  • Encourage patients to increase physical activity. While activities that involve weight bearing are more beneficial, the most important exercise is the one the individual will do with consistency. 
  • Teach the patient to take bisphosphonates with a full glass of water with each dose and to remain upright for at least 30 minutes to prevent esophageal irritation.

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