Joint Chiefs
Arthritis offers as much mystery as it does pain, but physicians are coming up with better treatments and more effective strategies to battle it.
Gather the millions of Americans with osteoarthritis or rheumatoid arthritis in a single place, and their mounting numbers could make them the second most populous state in the union, just behind California.
Taken together, both types of arthritis affect nearly 23 million people across the United States—a hefty portion of the population that struggles with seemingly ordinary daily tasks, from tying a shoe to opening a jar.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases reports that by age 65, more than half of all Americans have X-ray evidence of osteo-arthritis in at least one joint. Today, about
21 million people are thought to have the disease, accounting for 7 million doctor visits a year. With the baby-boom generation graying, the toll is expected to rise to 30 million by 2020.
Rheumatoid arthritis is rare by comparison. One person in every 100—about 2.1 million Americans—has it. Its price is high, however, both for those afflicted with it and for society: Within 10 years of being diagnosed with rheumatoid arthritis, half of all young, working patients become disabled.
Fortunately, new, more effective treatment strategies are helping more of these arthritis sufferers than ever before live a less painful and fuller life.
Complex conditions
Arthritis offers as much mystery as it does pain, because no one quite knows why it begins or why some get it while others remain immune.
One certainty: Each type of arthritis is different. Arthritis encompasses about 100 differing, complex conditions, such as gout, systemic lupus erythematosus and Crohn’s disease. This complexity holds the key to living successfully with arthritis: Once physicians diagnose a patient’s specific arthritis type, they can suggest appropriate strategies to battle it.
In the case of the much more common osteoarthritis, wear and tear on joints seems to play a big part, though susceptibility might be inherited. That can help guide treatment.
“Osteoarthritis is a degenerative joint disease that comes from an imbalance in the cycle of cartilage breakdown and regeneration,” explains Thomas Susko, M.D., assistant professor of medicine in the division of rheumatology and immunology at the Keck School of Medicine of USC. Cartilage is a flexible, elastic tissue that cushions the ends of bones and is nourished by joint fluid.
The theory, Susko says, is that stress in the joint eventually causes abnormalities in cartilage cells, leading to a release of chemicals that slowly break down joints. Cartilage becomes cracked, pitted and frayed, and the released chemicals cause inflammation—leading to pain.
Women, obese people, people age 45 or older, those with a family history of the disease and people who have suffered joint injuries are especially at risk.
While rheumatoid arthritis (RA) also causes joint pain and swelling, its origin appears far different.
“RA is an autoimmune disease that may have genetic factors,” says Glenn Ehresmann, M.D., associate professor of medicine in rheumatology and immunology. “Some believe infectious agents may be involved as well.”
Unlike osteoarthritis, which may cause pain in just one joint, rheumatoid arthritis is a systemic inflammatory illness. “It’s a disease of the entire body,” Ehresmann says. “The heart, lungs, kidneys, spleen, gastrointestinal tract, skin, nerves. It’s a whole-person problem.”
Like many autoimmune conditions, RA discriminates by gender, affecting two to three times as many women as men.
Rheumatoid arthritis can cut three to 18 years off a lifetime and can quickly disable patients within the first few years of its onset, Ehresmann says, making it critical to diagnose and treat early.
Various therapies
Although no one can cure osteoarthritis, health professionals and patients have many options to choose from when creating a customized plan to battle the problem.
Physicians first suggest weight loss to ease the burden on joints. They also encourage exercise—even if it seems challenging when joints hurt.
Knee specialist C. Thomas Vangsness, Jr., M.D., Keck School associate professor of orthopaedic surgery and chief of sports medicine at USC University Hospital, says some activities are better than others. “The wrong type of exercise actually increases the risk of developing or worsening the condition,” Vangsness says. “Specifically, any sport or activity that subjects joints to sustained high impact or heavy loading while moving is likely to cause or increase symptom progression in this disease.”
Occupational and physical therapists
create specific exercises for patients to strengthen muscles and keep joints from stiffening, and provide devices such as canes or braces for support.
Vangsness says today’s drugs cannot stop the disease itself. Instead, they aim to make it easier to live with arthritis.
Patients often start with acetaminophen, or Tylenol, says William C. Gong, Pharm.D., USC associate professor of clinical pharmacy. If appropriate, they may proceed to non-steroidal anti-inflammatory drugs, or NSAIDs, such as ibuprofen or naproxen. However, continuous or chronic use of high doses of NSAIDs can lead to stomach upset and gastrointestinal complications.
Gong says the COX-2 inhibitors— celecoxib (Celebrex), rofecoxib (Vioxx) and recently released valdecoxib (Bextra)— are becoming more popular because they control pain and cause fewer gastrointestinal complications.
Besides recommending topical creams, hot wax baths and heat or cold treatments, some physicians are giving patients the go-ahead to try the nonprescription supplements glucosamine and chondroitin. Although results from a study sponsored by the National Institutes of Health are pending, anecdotal evidence shows they may offer benefits, Vangsness says.
Surgeons also can provide alternatives. Vangsness drains fluid from the knees of selected patients suffering from early arthritis. He then injects Synvisc, a gooey, lubricating gel that contains the active ingredient hyaluronate, a natural chemical found in the body and in high concentrations in joint tissues. Synvisc and its competing product, Hyalgan, both require several injections over several weeks. Pain relief may last for several months, allowing some to avoid surgery.
For others in severe pain, surgical joint replacement (see accompanying story on page 23) or surgical removal of debris from joints may be best. And in the future, surgeons may increasingly replace worn-out cartilage in such patients with cloned cartilage cells—a procedure offered today primarily for those with cartilage damaged through injury.
Finally, struggles with arthritis have spawned a multitude of alternative therapies, from magnets to copper bracelets. Francisco Quismorio, M.D., professor of medicine at the Keck School, even discovered one patient who was infected with salmonella after ingesting snake oil.
“We tend to frown on these treatments,” Susko says. “They’re not proven.”
Disease targets
Health professionals usually favor trying the mildest treatments for osteoarthritis first. But when they diagnose rheumatoid arthritis in a patient, they treat it aggressively from the start.
In rheumatoid arthritis, immune cells called lymphocytes, which are supposed to fight foreign invaders, actually attack the body itself. In the process, cells release proteins (called cytokines) that cause inflammation.
One of these cytokines is tumor necrosis factor-alpha, or TNF-a.
TNF-a is the target for several relatively new drugs: infliximab (Remicade) and etanercept (Enbrel). The drugs “soak up” and flush away TNF-a in a patient’s body before it can reach immune system cells and kick off inflammation.
Known as biological response modifiers, this class of drugs actually slows progression of the arthritis—an important achievement since joints can quickly become distorted if the disease goes untreated.
“By the time there are deformities, medicine alone isn’t enough to make the situation better,” Ehresmann says. “We’d prefer to intervene before that happens.”
Biological response modifiers may work alone or alongside longer-standing medicines called disease-modifying antirheumatic drugs (DMARDs), such as methotrexate. However, DMARDs may cause significant side effects, so researchers are constantly seeking new, less-toxic options.
In the future, other aspects of the disease may become targets for treatments. Nori Kasahara, M.D., Ph.D., assistant professor of pathology at the Keck School and USC’s Institute for Genetic Medicine, for example, is investigating gene therapy to fight angiogenesis in rheumatoid arthritis. Angiogenesis, the creation of new blood vessels, is important to healing tissues after injury, but it also appears to play a part in the development of rheumatoid arthritis.
The Department of Medicine’s rheumatology and immunology division—consistently ranked in U.S. News and World Report’s top 20 rheumatology programs—is well-known for seeking roots of such autoimmune diseases.
David Horwitz, M.D., professor of medicine, molecular microbiology and immunology, and his colleagues are investigating how to target receptors on immune system cells themselves to block rheumatoid arthritis. And Ehresmann, Susko and rheumatology colleagues Rodanthi Kitridou, M.D., professor of medicine, and Daniel Arkfeld, M.D., assistant professor of medicine, are exploring promising new biological response modifiers through clinical trials.
One such new drug, called anakinra (Kineret), recently came on the market, targeting a different cytokine that causes inflammation: interleukin-1. This is just the beginning, according to the rheumatologists.
Says Ehresmann: “In the next decade, we expect much more exploration into proteins that cause damage—and investigation into how that to block that damage.”
For more information about arthritis research and treatment, or to learn more about The Doctors of USC, call 1-800-USC-CARE (1-800-872-2273).
- Back
- Next
- Index