Osteoporosis treatment puts brakes on bone loss

Osteoporosis treatment may involve medication along with lifestyle change. A Mayo Clinic specialist answers some of the most common questions about osteoporosis treatment.

Kurt Kennel, M.D.

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If you're undergoing osteoporosis treatment, you're taking a step in the right direction for your bone health. But you might find yourself facing unanswered questions about your therapy. Is the medication you're taking the best one for you? How long will you have to take it? Why does your doctor recommend that you take a weekly pill when your friend only takes a pill once a month?

Kurt Kennel, M.D., a specialist in endocrinology at Mayo Clinic in Rochester, Minn., answers these questions about osteoporosis treatment in women and describes how common osteoporosis medications work.

Which medications are most commonly used for osteoporosis treatment?

Bisphosphonates are — by far — the most common medications prescribed for osteoporosis treatment. Fosamax, Actonel and Boniva are just a few examples from this family of medications.

Hormones, such as estrogen, and some hormone-like medications approved for preventing and treating osteoporosis, such as raloxifene (Evista), also play a role in osteoporosis treatment. But fewer and fewer women are receiving these medications for osteoporosis treatment because the bisphosphonates are so effective.

Doctors, in general, feel comfortable prescribing bisphosphonates for osteoporosis treatment. Fosamax — a commonly prescribed bisphosphonate — has been on the market for about 10 years, so there's proven experience with safety. And bisphosphonates really don't affect anything but the bone. Hormones, on the other hand, raise some concerns about what effects they'll have on other parts of the body, such as the breast or circulation. With bisphosphonates, doctors have fewer concerns about side effects or medication interactions. These medications tend to be well tolerated, for the most part, by the women who take them.

How do bisphosphonates work?

Bisphosphonates slow the bone breakdown process. Healthy bones are in a state of continuous breakdown and rebuilding. As you get older, and especially after menopause when your estrogen levels decrease, the bone breakdown process accelerates. When bone rebuilding fails to keep pace, bones deteriorate and become weaker. Bisphosphonates basically put a brake on that. These drugs effectively preserve or maintain bone density during menopause — and decrease the risk of breaking a bone as a result of osteoporosis.

How do you know if you're taking the right medication?

Drugs in the bisphosphonate class are more alike than they are different. Some studies show differences in potency or effectiveness at maintaining bone density, but they're all still effective drugs. All bisphosphonates have been shown to reduce the chance of a fracture.

Commonly, the decision to take one drug over another is based upon preference, convenience and adherence to the dosing schedule. A doctor might recommend a monthly dose of medication if it's going to be better tolerated or better accepted. But if you're the type of person who might forget to take your medicine every month, you might do better taking it once a week.

Is there an advantage to an injected bisphosphonate versus a daily or monthly oral regimen?

There may be. Two infusion medications have been approved for osteoporosis treatment. Ibandronate (Boniva injection) is injected into your vein once every three months, and  zoledronic acid (Reclast) is injected once a year.

Adherence to osteoporosis medication dosing schedules is an important consideration. Researchers report that most women taking an oral bisphosphonate stop treatment or take less than the fully prescribed amount of medication after one year of therapy. This reduces the effectiveness of the medication. An injection given quarterly or yearly, on the other hand, ensures that women are fully protected until their next treatment.

Reclast injection, recently approved by the Food and Drug Administration, might be slightly more effective than other osteoporosis drugs. For instance, Reclast — unlike Boniva — has been shown to reduce the risk of hip fractures.

Finally, if you're like many, you might already take several pills a day to manage other health conditions. Or you might experience unbearable stomach upset from your current oral bisphosphonate. Switching to an injection provides a welcome alternative.

How long should you take a bisphosphonate for osteoporosis treatment?

Up to five years of treatment with bisphosphonates is safe and effective. The scientific literature is full of good studies of all the bisphosphonate medications that prove their safety and show their effectiveness at preventing fractures of the hip and spine for up to five years.

Beyond five years of treatment, there's less certainty. There just haven't been many long-term studies done. One thing we know, though, is that even if you stop taking the medication, its positive effects can still persist. That's because after taking a bisphosphonate for a period of time, you build up the medicine in your bone.

Because of this lingering effect, some experts believe it's reasonable for women who are doing well on treatment — those who have not broken any bones and are maintaining bone density — to consider taking a holiday from their bisphosphonate after taking it for five years. But if you're at high risk of fractures or you have very low bone density, taking a break from your osteoporosis medication probably isn't a good idea.

How long can a holiday from osteoporosis medication be?

If you're at low risk of fractures, you could take one year or even up to five years off. A recent report in the Journal of the American Medical Association shows that women who didn't take any medication beyond five years, and who took an inactive pill (placebo) between years five and 10 instead, still experienced protective effects from the bisphosphonates. Symptomatic vertebral fractures were a little more common in women who stopped the medication, but most other vertebral fractures, as well as hip fractures and wrist fractures, were no more common in people who stopped after five years than in those who kept going from years five to 10.

If you take a holiday from your osteoporosis medication, will you need to restart treatment at some point?

If you experience a major decline in your bone density or you have a fracture, you would need to go back on therapy.

Some women approach taking a holiday from their medications by establishing a predetermined restart date with their doctors. So, for instance, you could take a break of one or two years, all the while knowing you'll restart your medicine when that period is over.

What are the side effects of bisphosphonates?

The most common side effect with any of the bisphosphonates is stomach upset or heartburn. To ease this potential side effect, take the medication on an empty stomach with a tall glass of water. And don't lie down or bend over for 30 to 60 minutes to avoid the medicine washing back up into the esophagus. The majority of women who follow these tips don't experience this side effect. But it's possible for an unlucky few who take the medicine correctly to still have stomach upset or heartburn.

There's also a theoretical concern about getting too much of a bisphosphonate in your bones, causing the bone to actually become more fragile over time. But in the longer term follow-up studies, this complication hasn't been apparent. Researchers just aren't finding that women suddenly go from having fewer and fewer fractures to having more fractures as they go beyond five years of treatment.

The bisphosphonates could potentially cause osteonecrosis of the jaw — a rare condition in which a section of jawbone dies and deteriorates. The bisphosphonates, as a family of medications, have the potential to affect the jawbone. This side effect occurs primarily in people who take very large doses of the medication by vein (intravenously) — much larger than the doses typically used for osteoporosis — because they have cancer in their bones. In these individuals, a small number have poor healing of the jawbone after a dental extraction, after trauma to the jaw or sometimes even just spontaneously.

The American Dental Association estimates that the risk of osteonecrosis of the jaw in a woman taking bisphosphonates by mouth for osteoporosis is less than one in 100,000. Before you start taking a bisphosphonate, make sure your teeth are healthy. There's no recommendation to stop the medication before having a dental procedure, but do tell your dentist you're taking a bisphosphonate and follow his or his recommendations for good oral hygiene.

Can medication alone successfully treat osteoporosis?

It's unwise to rely entirely on medication as the only treatment for osteoporosis. Weight-bearing physical activity also is important — for two reasons. It works directly to strengthen bones, and it improves your balance. The more active and fit you are as you age, the less likely you are to fall and break a bone.

Good nutrition in general is key, but you should also make certain that you're getting enough calcium and vitamin D. Being underweight or losing a lot of weight unintentionally is associated with poorer bone health and a higher risk of fracture — even if you're taking a bisphosphonate.

Quitting smoking is beneficial for your bones, as is limiting alcohol to no more than one drink a day.

What kind of follow-up tests are recommended while undergoing osteoporosis treatment?

Follow-up bone density testing may be done one or two years after you start a medication for osteoporosis. A bone density check can reassure you that the medication is working. If your bone density has gone down dramatically, it may prompt your doctor to re-evaluate you, in case an undiscovered medical problem could be weakening your bones.

Beyond that first follow-up bone density test, you don't really need any further testing. However, it's common for women to continue to have bone density tests to monitor their bone health. It's one tangible measure that can tell a woman her medication is working. But if you're doing well on your medication — not experiencing fractures, for instance — it's not necessary.

If you opt for regular bone density testing, you'll probably be tested every one to two years. If you're doing well on the medication but you want continued monitoring, that interval may increase to every three to five years.

How do you know if your osteoporosis treatment is working?

If you've not had any fractures, then your medicine is working. But it's hard for women to trust in the medication and its benefit for them when they don't have anything tangible to measure. That's one reason why follow-up bone density testing is commonly performed. Some argue that the best reason for doing bone density tests every two years is to reinforce the importance of the treatment. A woman can see good results from the test and continue to feel positive about taking this medicine every week — even though it's unusual that her bone density would be worsening.

Adherence rates for taking osteoporosis medication are poor. The International Osteoporosis Foundation estimates that fewer than half of U.S. women who start taking a weekly pill are still on their medicine after one year. And only about a third of women keep taking daily pills for a year. For a woman who wonders what she's getting out of treatment or how well it's working, regular bone density checks and reviewing with her doctor the reasons for continuing medication are reasonable ways to monitor the treatment.

What happens if you experience a broken bone while taking an osteoporosis medication?

Osteoporosis medications lower the chance of fracture, but they don't eliminate all risk of breaking a bone. If you have a fracture while on treatment, you need to be reassessed by your doctor. You may have developed new conditions that cause fractures, such as unsteadiness or falling, which are assessed separately from osteoporosis medications. Some women may be candidates to switch to a more aggressive bone-building therapy.

One type of medication more potent than bisphosphonates is a bone-building drug — parathyroid hormone, manufactured as teriparatide (Forteo). This treatment is typically reserved for women who are at very high risk — those with very low bone density or who have had fractures. Teriparatide has the potential to rebuild bone and actually reverse osteoporosis, at least somewhat.

Do you need to take a calcium or vitamin D supplement when you're undergoing osteoporosis treatment?

Nearly every study of bisphosphonates has also included calcium and vitamin D supplementation. Most experts cautiously agree that for those medications to work effectively — to get the same results the studies produced — women need adequate amounts of calcium and vitamin D.

The guideline for the recommended daily amount of calcium remains 1,500 milligrams, but that includes dietary intake. If you're already consuming a generous amount of calcium in your diet — such as by having three to four servings of dairy products or fortified foods a day — taking more via a supplement may not do you any good. Likewise, a woman who has liberal sun exposure, or other sources of vitamin D, may not need extra vitamin D.

But if you're not getting adequate amounts of calcium and vitamin D in your diet, it's a good idea to take a supplement.

What should you look for in a calcium supplement?

Look for two things. First, your calcium supplement should contain vitamin D — and most calcium supplements do contain this vitamin. Women with osteoporosis often have vitamin D deficiency.

Second, find the pill or tablet that will be easiest for you to take. Do you prefer a chewable tablet over swallowing a large pill? Pay less attention to the type of calcium — calcium citrate versus calcium carbonate — and whether it's a brand name or generic.

The day-to-day difference of how much calcium you absorb from different supplements is so small as to be inconsequential compared with your consistency in taking the supplement.

It's also often suggested that calcium supplements should contain magnesium. But magnesium is everywhere in our diet. It's unusual for someone to really need a magnesium supplement.

How important is exercise if you're undergoing osteoporosis treatment?

Weight-bearing physical activity is very important, not only for building bone strength, but also because of what it's going to do for your overall health. The less active you are as you age, the more frail you become and the greater your risk of falls and fractures.

How can you make sure you're exercising safely and not increasing your risk of an osteoporosis-related fracture?

Take a common-sense approach to physical activity. Make sure you can do an activity safely — without risk of falling or awkward lifting. Skip activities that make you strain beyond your usual limits or increase your risk of falling. Pay attention to your environment and avoid performing activities in poor weather or under other conditions that make you feel unsafe. Seek the advice of a physical therapist or instruction from your doctor for correct technique and safe exercise if you're unsure.

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