Influence of Medications
If you have known osteoporosis, medical treatment that reduces your risk of fracture is important. New drugs continue to be developed, and new formulations of current drugs are being made to improve effectiveness while reducing side effects. It is important to remember, however, that although many of these drugs can effectively reduce fracture rates by up to 50 percent, none are 100 percent effective. Thus, it is important to consider all of the factors that contribute to fracture risk (e.g., exercise, nutrition, falling) to ensure that you follow a comprehensive program that may include drug management.
Most of the drugs currently approved by the U.S. Food and Drug Administration (FDA) for the management of postmenopausal osteoporosis are called antiresorptive. They increase bone density by rendering the cells that break down bone inactive while leaving alone those cells that form bone. Drugs in this category include estrogens, calcitonin, bisphosphonates, denosumab, and selective estrogen receptor modulators. Two drugs have been shown to reduce fracture by actually stimulating bone-forming cells: parathyroid hormone (brand name, Forteo) and strontium ranelate (brand name, Protelos). The latter, however, has recently been restricted to use in those with severe osteoporosis due to an increased risk for heart attack.
The class of drugs called bisphosphonates is currently the most widely used to reduce osteoporotic fractures. Several forms of bisphosphonates are currently available: alendronate (brand name, Fosamax or Fosamax Plus D), risedronate (brand names, Actonel, Atelvia), ibandronate (brand name, Boniva), zoledronic acid (brand names, Reclast and Zometa), and calcitonin (brand names, Fortical and Miacalcin), just to name a few. On average, these drugs increase bone density by 4 to 8 percent at the spine and 1 to 3 percent at the hip over the first three to four years of treatment. This small increase can actually reduce the risk of vertebral fractures by 40 to 50 percent and nonvertebral fractures (including hip fractures) by as much as 20 to 40 percent.
Despite the impressive potential of bisphosphonates to reduce fractures, new studies are questioning their long-term safety. These drugs remain in the skeleton for decades, and bone turnover can be affected for up to five years after the drugs are discontinued. Recall that bone remodeling is a natural process that allows the body to repair microdamage due to everyday wear and tear. If bisphosphonates prevent breakdown and bone renewal, the concern is that bone could become brittle. Furthermore, the rare but serious disorder called osteonecrosis of the jaw (a condition characterized by pain, swelling, infection, and exposure of bone) has been associated with bisphosphonate use, mainly in patients receiving high doses in combination with cancer treatment. While experts have not come to a concrete consensus on how long bisphosphonate therapy should be continued, preliminary clinical recommendations state that 3 to 5 years of treatment is probably sufficient for someone with mild risk of fracture, 5 to 10 years of treatment for those with moderate risk of fracture followed by a drug “holiday” of 3 to 5 years, and 10 years of treatment for those with high risk of fracture followed by a 1- to 2-year drug holiday and reevaluation.
Hormone therapy (HT, a combination of estrogen and progesterone) and estrogen therapy (ET) offset the estrogen-related bone loss associated with menopause and even cause a slight increase in hip and spine bone density that plateaus after three years of use. Studies show that HT and ET reduce the incidence of fractures of the hip and spine by 30 to 50 percent. Hormone therapies are currently approved to reduce postmenopausal bone loss as a means to prevent osteoporosis but are ineffective at preventing bone loss in men. To be most effective at preventing bone loss, therapy should begin close to, if not a few years before, the menopausal transition. After the publication of the Women’s Health Initiative study in 2002, the role of long-term postmenopausal HT and ET for the prevention and management of osteoporosis became controversial because of a suspected increased risk of cardiovascular events.
You may be wondering whether HT or ET is appropriate for you. Consulting with your health care provider, who has an understanding of your complete health picture, is best. The FDA currently recommends that HT not is taken to prevent heart disease; and although it is effective for the prevention of osteoporosis, it should be used only by women with a significant risk of fracture who cannot take antiresorptive medication. For other women at risk for osteoporosis, the FDA favors the use of antiresorptive agents and only short-term use of HT around menopause in women with menopausal symptoms or those at risk for fracture.
Selective estrogen receptor modulators (SERMs) represent a class of agents that, although similar in structure to estrogen, exert their effects only on target tissues. The most widely studied are raloxifene (brand name, Evista). Its overall effect is more modest than that of bisphosphonates, and its effect on hip fractures has not been marked. For this reason, it is recommended for women with milder osteoporosis or for those with osteoporosis primarily in the spine.
Because each person’s health history is unique, your choice of medication should be made with your health care provider in light of your total health situation. Pros & Cons Medications table list the pros and cons of common osteoporosis medications.