Updates on Osteoporosis Incidence, Recognition and Treatment

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By Malini Ganesh, MD, and Garnet Meier, MD
Picture of internal bone structure of spine

The prevalence of osteoporosis, a condition of weak and brittle bones that predisposes you to fractures from commonplace trauma like coughing, twisting and falling from standing height, continues to be a serious public health concern. The “silent” condition doesn’t usually cause pain until you experience a fracture.

Worldwide, one in three women over age 50 will experience osteoporotic fractures, as will one in five men over 50 years of age. Fractures in older adults, especially hip fractures, can lead to prolonged hospital and nursing home stays, which in turn can predispose a person to life-threatening infections. A recent study found that the annual cost of caring for osteoporotic fracture exceeds that of caring for breast cancer, myocardial infarction, or stroke in women aged 55 years and older.

Why does it occur?

Formation of new bone and removal of old bone is a lifelong process. Osteoporotic bone can be thought of as resembling Swiss cheese, but with more holes as you age, and hence is weaker. Most adults reach peak bone strength and density in their 20s and 30s. After this, bone strength declines slowly with age.

The amount of maximum bone strength you reach influences your risk for osteoporosis. This, in turn, is influenced by both genetic and environmental factors. For example, if you are thin, Caucasian and female, with a family history of thin bones, you will probably achieve less peak bone mass. Long-standing calcium or vitamin D deficiency can lead to slow weakening of the skeleton. Plus, other medical conditions can predispose you to develop thin bones, among them kidney and liver disease, use of steroids (such as prednisone), rheumatoid arthritis, cancer and chemotherapy, and hormone issues like an overactive thyroid, parathyroid, or adrenal gland. Moreover, environmental factors that make you likelier to fall (such as stroke, impaired vision or hearing and muscle weakness) also increase your risk for fractures.

How is osteoporosis diagnosed?

A bone density study or DEXA (Dual-energy X-ray absorptiometry) assesses your bone mineral density, also known as BMD, which typically is very low in osteoporosis. Also, it can be diagnosed if you have a low-trauma fracture even without a DEXA study. A diagnosis of osteopenia on a DEXA study indicates “pre-osteoporosis” status, which is serious as well since the majority of osteoporotic fractures occur before a DEXA scan reveals osteoporosis. In this case, doctors may use an online risk calculator called FRAX® (fracture risk assessment tool), which estimates your risk of having a fracture. If fracture risk is high, then treatment is recommended, even for osteopenia.

What can you do for your bone health?

Guidelines created by experts from the American Association of Clinical Endocrinologists (AACE) recommend certain fundamental measures to ensure good bone health, including:

  • Calcium intake (1200mg daily)
  • Adequate vitamin D supplements (1000-2000 international units daily)
  • Limiting alcohol intake
  • Quitting smoking, and
  • Regular exercise, including weight-bearing or resistance training. If you are older, physical therapy may be needed to help, especially with fall-proofing your home to make it safer.

What medications are used to treat osteoporosis?

Medications used to treat osteoporosis work by either preserving your bone (bisphosphonates, denosumab, estrogen, calcitonin or raloxifene), or increasing the formation of new bone (teriparatide).

Bisphosphonates (alendronate, risedronate, ibandronate, zoledronic acid) can be used as a pill or as an injection and are usually the first medications suggested since they are excellent at preventing both hip and spine fractures. However, they should not be prescribed to patients with kidney disease, or those who cannot tolerate bisphosphonates due to gastrointestinal acid reflux or allergic reactions. Denosumab is an every-six-months subcutaneous injection that prevents both hip and spine fractures and can be prescribed to those who are unable to take bisphosphonates. Another prescription treatment option is teriparatide (Forteo®, daily injection) which helps to stimulate the formation of new bone and may be particularly helpful in people with very low bone mass or those intolerant to other forms of therapy. However, it should not be prescribed to patients who have had radiation therapy to the bone or certain other bone diseases.

The second-line therapies approved in the U.S. are raloxifene, which reduces spine fractures although the effect on hip fractures is not as certain, and calcitonin, which reduces risks of spine fracture but not clearly in the hip and may also help relieve pain from acute spinal fractures.

How is treatment measured and monitored?

The goal of monitoring osteoporosis therapy is to identify patients who continue to have bone loss despite therapy. Ideally, monitoring should be done at the same center using the same machine and technologist as the previous DEXA scans and should include both hips and the spine.

  • Good response: DEXA scan shows a stable or increasing BMD
  • Poor response: DEXA scan shows significant decrease of BMD or a fracture while on treatment. If this happens, your doctor will make sure you are taking your osteoporosis medication adequately and will rule out any other conditions that might be affecting your bone health.

Usually, your doctor will check a DEXA scan every one to two years after starting the treatment. Once your BMD has been stable, you doctor may repeat the DEXA at longer intervals.

How long should I be treated?

Your FRAX score will determine the duration of the osteoporosis treatment.

  • If your fracture risk is high, guidelines recommend continuing treatment with osteoporosis pills such as alendronate or risedronate for 10 years, or yearly infusions of intravenous osteoporosis medication (zoledronic acid) for six years. Based on current knowledge, it’s yet unclear what the risks and benefits of treatment beyond 10 years.
  • If your risk is low, your doctor may consider taking you off the medication after five years of BMD stability on osteoporosis pill treatment or three years of yearly infusion osteoporosis treatment (known as a “drug holiday”).

What are the risks of osteoporosis medication?

There are mainly two adverse events from osteoporosis medications that are of concern.

  • Osteonecrosis of the jaw – Some cases have been reported previously that in high doses of osteoporosis medications, sudden decay of the bone cells of the jaw has occurred that does not heal. The probability of this complication happening now on the current doses is very low. In comparison, the risk of fracture in untreated osteoporosis is much higher than that of osteonecrosis of the jaw. Risk factors for this complication include dental disease, dental procedures, and poor oral hygiene. Your doctor may examine your teeth before prescribing osteoporosis therapy. If significant dental issues are detected, your doctor will consider delaying osteoporosis therapy until these dental issues are addressed. For patients who are already receiving treatment and need dental procedures, there is no evidence that stopping the treatment will reduce the risk.
  • Atypical femur fractures – These are fractures of the middle of the long bone of the thigh that happen with little or no trauma. It may happen after many years of treatment or after abruptly stopping medications without proper continuation of care. The probability of this complication happening is low, but should be suspected if sudden onset of groin pain is experienced, especially if treatment was stopped abruptly.
  • Atrial fibrillation – While the benefit of bisphosphonates greatly outweighs the risk of developing atrial fibrillation, patients with pre-existing heart conditions like congestive heart failure or valvular heart disease should be aware of this possibility.
  • Esophageal cancer – A rare potential side effect of oral bisphosphonates is esophageal cancer. However, nationwide, multiple large-scale studies have failed to provide evidence for any increased risk of esophageal cancer with the use of oral bisphosphonates. Oral bisphosphonates, if not taken appropriately (sitting upright, with a glass of cold water, and not lying down for 30 minutes after), can stick to the food pipe and cause ulcers. Hence, patients with preexisting conditions like esophageal ulcers, Barrett’s esophagus, or narrowing of the esophagus may be better served by IV bisphosphonates.

Is treatment more effective using two or more osteoporosis medications in combination rather than using only one?

Guidelines currently do not recommend the combined use of two osteoporosis medications. There is no proven benefit in either fracture risk or improvement in DEXA scan. Moreover, costs are increased and adverse effects could be higher.

When should I be referred to a clinical endocrinologist or osteoporosis specialist?

Your doctor may consider referral to a specialist if you have:

  • Normal bone density on DEXA scans but sustained fractures without significant trauma
  • Recurrent fractures
  • Continued bone loss while receiving therapy
  • Other associated diseases causing your bones to be brittle
  • Severe or unusual cases of osteoporosis
  • Other associated diseases (such as renal disease) which may complicate treatment