You Have Osteoporosis. What’s Next?

You recently had a DEXA bone density scan. You have been told you have osteopenia or osteoporosis – i.e. mild or more significant bone thinning, respectively – which carry a higher risk of fracture than normal bone density. Your physician recommends treatment with medication. When you go to research options, you are overwhelmed by the choices. I hope to clarify the treatment options currently available.

First let’s discuss bone physiology. Bone is living, growing tissue that constantly forms new bone while replacing older bone in a process called remodeling. This cycle consists of two distinct stages: (1) bone resorption (breakdown or removal) and (2) bone formation. During resorption, special cells (osteoclasts) on the bone’s surface dissolve bone tissue and create small cavities. During formation, other cells (osteoblasts) fill the cavities with new bone tissue. Usually, bone resorption and bone formation take place in close sequence and remain balanced. An imbalance in the bone remodeling cycle occurs with menopause, aging in both genders, and can occur with other medical conditions or medications such as steroids, thyroid replacement and anti-seizure medications to name a few. This imbalance results in bone loss in excess over bone formation, leading to osteoporosis and fractures.

What are your treatment options?

Current treatments either slow bone resorption or enhance bone formation but not both.

1) BISPHOSPHONATES – Fosamax (alendronate), Actonel (risedronate), Boniva (ibandronate) and Reclast (zolendronic acid) all help slow bone loss, and decrease the risk of fractures. The first three are available orally, while zolendroic acid is given intravenously once a year in patients unable to tolerate oral medications. In addition, alendronate, risedronate, and zolendroic acid have been shown to reduce both spine and hip fractures. Ibandronate lacks consistent clinical trial data that it reduces hip fracture risk so I am less apt to prescribe even though it is available in a convenient once monthly dosing.

Patients are understandably concerned about the side effects of medication. Gastrointestinal symptoms and joint pain are the most common ones seen with the bisphosphonates. The side effects more often discussed, even though they are rare, include osteonecrosis of the jaw (ONJ) and atypical femoral fractures. There have been reports of ONJ (permanent damage of the bones of the jaw) after use of bisphosphonates, mostly in people who recently had a dental procedure or had dental disease. Estimate in the general population for ONJ is less than .001% and for patients taking osteoporosis medication the risk rises slightly to between .001-.01%. The highest risk group is cancer patients taking much higher doses of bisphosphonates where the rate rises to 1-15%.

Atypical femoral fractures, which are uncommon types of thighbone fractures, have occurred in a small percent of people using bisphosphonates long term for their osteoporosis. Again, this risk appears to be very low, especially relative to the number of fractures that bisphosphonates prevent. Treatment of osteoporosis with bisphosphonates for up to five years is not associated with atypical fractures and is not a reason to defer bisphosphonate therapy in women who are at high risk for osteoporotic fracture

2) PROLIA (DENOSUMAB) – Similar to bisphosphonates this medication is an antiresorptive (i.e. slows down bone loss). It is a fully human monoclonal antibody, a type of immune therapy. It interferes with the survival of bone-resorbing cells and thereby prevents both vertebral and hip fractures. Its side effects include joint achiness, low serum calcium and rashes, such as eczema. Your doctor will monitor for low calcium levels. There may be a slightly increased risk of infections when using this drug. There have also been rare reports of ONJ linked to use its use.

3) EVISTA (RALOXIFENE) is in a class of medications known as selective estrogen receptor modulators-or SERMs. They mimic estrogen’s good effects on bones to slow bone loss. Raloxifene decreases the risk of spine fractures in women but, like ibandronate, hasn’t been proven to reduce hip fractures. An added benefit is reduction in breast cancer risk. So, raloxifene is usually chosen for osteoporosis when breast cancer risk is an issue. However, there is an increased risk of blood clots and stroke.

4) ESTROGEN OR HORMONE REPLACEMENT – Slows bone loss. Estrogen treatment alone or combined with progestin decreases the risk of osteoporosis and osteoporotic fractures in women. However, combined estrogen and progestin can increase the risk of breast cancer, strokes, heart attacks and blood clots and is therefore no longer a first-line approach for the treatment of osteoporosis in postmenopausal women.

5) FORTEO (TERIPARATIDE) – Teriparatide is a form of parathyroid hormone. In contrast to all the other treatments, it is the only medication available to stimulate bone formation and build bone. It is given as a daily injection under the skin and can be used for up to two years. If you have ever had radiation treatment or your parathyroid hormone levels are already too high, you may not be able to take this drug. There is no association with ONJ or femoral fractures. Use is limited to two years due to increased risk of bone tumors in rodents, but no increase risk has been seen in humans when prescribed correctly. Normally, it is not given as initial treatment unless the patient has severe osteoporosis or osteoporotic fractures. Side effects may be mild nausea, leg cramps; calcium levels must be monitored.

Which medication to choose?

Your physician will discuss options.  As you can see from the information above, many factors come into play, and the best medication for YOU depends on your particular circumstances.

For initial treatment, I normally recommend an oral bisphosphonate such as alendronate or risedronate weekly unless there is a contraindication. Infusion of zolendronate is a good option in those with significant stomach issues. Denosumab is not considered as initial therapy for most patients with osteoporosis. However, it could be used as initial therapy in certain patients at high risk for fracture, such as older patients who have difficulty remembering to take oral bisphosphonates, patients with marked kidney disease or those intolerant or unresponsive to other therapies. Teriparatide may be recommended as initial therapy to patients with severe osteoporosis and fragility fractures.

Remember, with any of these medications, it is vital you take enough calcium and vitamin D. The National Osteoporosis Foundation (NOF) recommends 1,000 mg per day of calcium for most adults and 1,200 mg per day for women over age 50 or for men over age 70. Vitamin D helps your body absorb calcium from the foods you eat. NOF recommends 800–1,000 IU of Vitamin D3 for those age 50 and older. However, you may need a different dose depending on your blood level of vitamin D, which your doctor can measure. Get exercise most days, especially weight-bearing exercise, such as walking.

How Long to Treat

Length of treatment is individualized and based on the person’s medical and fracture history, as well as the initial and most recent bone mineral density test results (DEXA). Your physician will reevaluate you yearly and decide whether to continue, discontinue or switch medication. In some patients we will consider a drug holiday usually at three years with zolendroic acid (Reclast) and five years with oral bisphosphonates. This means stopping the medicine for a period of time while continuing to monitor bone mineral density. Data on the ideal duration of denosumab therapy is lacking. Denosumab has demonstrated efficacy for ten years. Discontinuation results in bone loss within a relatively short time.

When to restart medication after a drug holiday is unclear. There are no data to support one strategy over another. In clinical practice, the decision to resume the drug is often based on a combination of factors, including duration of the holiday, decrease in bone mineral density on your DEXA, clinical risk factors for fracture, and increase in markers of bone turnover.

Many patients I see are reluctant to start medication for a silent disease that poses no symptoms until fracture occurs. But remember these statistics. About 54 million Americans have osteoporosis and low bone mass. Half of all women over the age of 50 will have a fracture of the hip, wrist, or vertebra during their lifetime. The lifetime risk of hip fracture is 17.5 percent for women and 6 percent for men. Approximately 90 percent of hip fractures in the elderly occur from a simple fall from the standing position. One in five hip fractures results in death within a year of injury and one in three adults who lived independently before their hip fracture remains in a nursing home for at least a year. Protect your bone health by doing weight-bearing and balance exercises and by reviewing your bone density and your calcium and vitamin D intake with your physician.