Osteoporosis sufferers are benefiting from several new drugs that have come on the market in recent years and can look forward to the arrival of a number of new drug treatments, but despite such advances, the battle for better bone health is far from won.
One in every two women over the age of 50 in the U.S., and one in four men, will have an osteoporosis-related fracture in their remaining lifetime, says the National Osteoporosis Foundation. The disease, which is characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and increased susceptibility to fractures, is a major health threat for 44 million Americans, or more than half of all people age 50 or older, the foundation says.
In Spokane, hip fracture rates are much higher than they should be, and osteoporosis often plays a role in such fractures, says Dr. Lynn Kohlmeier, of Spokane Osteoporosis Centers.
This year, Spokane-area osteoporosis sufferers will take part in studies of two new drugs that have yet to receive approval from the U.S. Food and Drug Administration. In a study expected to start in a couple of months, about 20 patients here will take a drug called denosumab, a monoclonal antibody thats injected twice a year into osteoporosis sufferers to increase bone mineral density, Kohlmeier says. Monoclonal antibodies are all clones of a single parent cell.
The study will compare denosumab with another osteoporosis medication called Fosamax, which has been on the market for some time. So far, denosumab has had excellent preliminary data, says Kohlmeier, who expects it could be approved within the next two years.
Also early this year, Spokane Osteoporosis Centers plans to enroll about 20 patients in a trial for Reclast, which is part of a class of drugs called bisphosphonates and is administered during a 15-minute intravenous infusion once a year.
Reclast is a lower-dose version of another drug called Zometa, which has been used to treat cancer that has spread to bone. In studies thus far, Reclast has shown fantastic fracture reduction in hip and spine, she says. Reclast could be approved as soon as next year, she says.
Meanwhile, a new designer estrogen, called bazedoxifene, which is part of a class of drugs called selective-estrogen receptor modulators (SERMs), could become available in a couple of years, says Dr. Jill Gronholz, of Bone Density of North Idaho, located in Coeur dAlene. Earlier, Gronholz enrolled 15 patients in a multi-center study of that drug in a much larger trial. The results of that trial were sent to the FDA, but the drug hasnt been approved yet, she says.
Also, the drug strontium ranelate, which has been approved in Europe but not in the U.S., has been shown to stop the breakdown of bone and to stimulate new bone growth, says Dr. Fred Viren, of the Spokane Osteoporosis Detection & Treatment Center here. Viren expects that it will be approved in the U.S. eventually.
In the last decade, drug makers have introduced several new osteoporosis medications. Fosamax and Actonel, bisphophonates that are taken orally once a week, have been shown to reduce hip and/or non-spinal fractures in addition to spinal fractures, Kohlmeier says. A third bisphosphonate, Boniva, can be taken orally once a month and recently has become available via an intravenous infusion given every three months, she says.
In rare instances, individuals receiving intravenous bisphosphonates for cancer treatment have developed osteonecrosis of the jaw, which involves severe destruction of the jawbone, says the American Dental Associations Web site. In even rarer cases, patients taking oral bisphosphonates have developed osteonecrosis. Most osteonecrosis cases have been diagnosed after dental procedures such as tooth extraction, the site says.
Viren says potential risks are important to consider when taking almost any drug, including bisphosphonates, but the benefits of bisphosphonates for osteoporosis patients far outweigh those risks.
Another drug, Evista, is a SERM that helps build bone and also has been shown to reduce the risk of developing breast cancer by about 50 percent in women who are at high-risk for breast cancer, but isnt FDA approved for breast-cancer deterrence yet, Kohlmeier says. SERMs block the action of estrogen in the breast and other tissues by occupying estrogen receptors inside cells.
Another drug, called Forteo, is whats known as parathyroid hormone that stimulates new bone formation, she says. Forteo is injected into the body daily and has been shown to reduce both non-spinal and spinal fractures.
The fact that we can now understand that we can stop excessive breakdown of bone with medications and use medications that stimulate formation of new bone is a big advance, Viren says. More attention has been paid to osteoporosis, but not enough.
The federal government dealt a huge blow to osteoporosis prevention and treatment efforts when it enacted legislation two years ago that will result in fewer tests being done to diagnose the disease, Gronholz says. The decision came three years after President Bush declared the years 2002-2011 the National Bone and Joint Decade, she says.
As part of the Deficit Reduction Act of 2005, Medicare reimbursement for bone-density testing will be cut by 40 percent starting this month, Gronholz says. A 70 percent reduction by 2010 also has been proposed. A bone-density test is similar to an X-ray and involves testing bone in the hip, spine, or heel to determine if a person has osteoporosis or could develop it.
Medicare doesnt pay a fortune for this service anyway, Gronholz says. Now, its going to be more difficult to get bone-density testing done, people are going to go undetected, and bone-testing facilities are going to go out of business.
Kohlmeier says she also is concerned about the effects of the new legislation on osteoporosis detection and treatment. Spokane Osteoporosis Centers offers bone-density testing at three sites in the Spokane area.
Free bone-density tests, which are done on the heel with ultrasound, are offered at community education screening centers at Deaconess Medical Center, Valley Hospital & Medical Center, and Sacred Heart Medical Center, she says. Free heel-bone density tests also will be offered at a triathlon that will support osteoporosis awareness in Medical Lake this summer.
In addition to drug therapies and bone-density screening, weight-bearing exercise, a calcium-rich diet, and taking vitamin D are important factors in fighting and preventing osteoporosis, Viren says. The U.S. Surgeon General recommends 15 to 20 minutes of exercise five times a week to maintain proper bone strength, and an adequate calcium intake is 1,200 to 1,500 milligrams a day, he says. Viren says two-thirds of Americans have vitamin D deficiency, and the federal government recommends a vitamin D intake of 400 to 600 units a day. The deficiency is more common in residents of northern U.S. states, because direct sunlight is a source of the vitamin, he says.
The most important advance in recent years has been the understanding of vitamin D deficiency, Viren says. With adequate doses of that and calcium, we can prevent this disease.
Late last month, researchers released the results of a large study in Britain that found taking popular heartburn drugs, such as Nexium, Prevacid, and Prilosec for a year or more can raise the risk substantially that people over 50 will suffer a broken hip. The researchers suspected that the drugs, which are part of a class of medicines called proton pump inhibitors, make it more difficult for the body to absorb calcium by reducing acid in the stomach. The study found a smaller risk of hip fractures for another class of drugs, called H2 blockers, which include Tagamet and Pepcid.
Kohlmeier says that healthier intakes of vitamin D and calcium might compensate for the potential decrease in absorption from proton pump inhibitors. She adds, though, that there might be other ways such drugs affect fracture risks as well.
Gronholz says that in addition to dietary supplements and exercise, women also can prevent fractures caused by falls by wearing hip protectors. People also should abstain from known risk factors such as eating disorders, smoking, and excessive alcohol consumption, she says.
Contact Emily Brandler at (509) 344-1265 or via e-mail at emilyb@spokanejournal.com.