Rheumatoid Arthritis and Osteoarthritis - Understand the Difference
by Jenifer Maxon, Medically reviewed by Dr. David Borenstein 9/1/12018
At first glance the word arthritis seems straightforward: it means “joint inflammation.” The reality, however, is far more complex. There are several different types of arthritis, and the two most common—rheumatoid arthritis (RA) and osteoarthritis (OA)—have very different causes, symptoms, and treatments.
Rheumatoid arthritis affects an estimated 1.3 million adults in the United States.1 The condition can have a profound effect on many aspects of daily life and is often poorly understood by those who have not had direct experience with it.
RA is an autoimmune disease that can affect the entire body. An autoimmune disease occurs when the immune system—which normally protects the body from infection—turns against some of the body’s own tissues. Other examples of autoimmune diseases are type 1 diabetes, lupus, Graves’ disease, and multiple sclerosis.
In the case of RA, the immune system attacks certain tissues within the joint. It’s unclear what starts this process, but some combination of genetic and environmental factors is likely to play a role. Factors that increase the likelihood of RA include being female, smoking, and having a family history of rheumatoid arthritis.2,3
The joint problems that people with RA experience include pain, swelling, and stiffness. Without early and effective treatment, the inflammation associated with RA can permanently damage bone and cartilage in the joints. Rheumatoid arthritis can also affect the entire body, particularly if the RA becomes severe.4 In addition to joint problems, people with RA may notice occasional fevers, fatigue, and a sense of being generally unwell. RA can lead to anemia (low red blood cell count) and, less commonly, to problems with the blood vessels, lungs, heart, and other organs.
Early Treatment Improves Outcomes
Although there is no cure for RA, early and aggressive treatment has improved outcomes for many people. Treatment of RA often begins with methotrexate or another disease-modifying antirheumatic drug (DMARD). If this initial treatment does not adequately control the RA, people may move on to treatment with a newer, biologic DMARD.
Effective drugs have dramatically improved RA outcomes, but, according to James K. Smith, MD, a rheumatologist at Northwest Rheumatologists in Portland, Oregon, public awareness of newer types of drugs remains low: “I’m shocked by the number of people who don’t know anything about [the biologics].” Although these drugs allow many people to achieve a remission (few or no RA symptoms), Dr. Smith notes that prompt diagnosis and early treatment are tremendously important to treatment success. Explaining some of the barriers to early diagnosis, he says, “No insurance, a high deductible, a belief that doctors can’t help you—there are lots of reasons why people don’t go to the doctor. That delays the diagnosis.”
In addition to effective drug therapies, engaging in regular, moderate exercise can help maintain joint flexibility and muscle strength and also improve overall health. People with RA who are considering an exercise program should work closely with their healthcare team to identify a regimen that meets their individual needs.
Osteoarthritis affects an estimated 27 million adults in the United States.5 Unlike RA, OA is not an autoimmune disease but rather a condition characterized by the breakdown of cartilage in a joint, which also involves changes to bone, ligaments, and other parts of the joint.
Normally, cartilage covers the ends of bones, acting as a shock absorber and allowing bones to glide smoothly past each other. As cartilage is lost, bones can begin to rub against each other, causing pain and swelling. Osteoarthritis can affect any joint, but most commonly affects the hands, knees, hips, or spine.6Factors that increase the risk of osteoarthritis include aging, being overweight, joint injury, and stress on a joint.
The Importance of Physical Activity
Although it may seem counter intuitive, staying physically active is one of the best ways to manage osteoarthritis. Exercise strengthens the muscles that support joints and also helps keep joints flexible. One of the keys, however, is avoiding overuse of any single joint. “Rotate your activities,” advises Dr. Smith. “Cross-train. This applies even at the level of Olympic athletes. Runners don’t just run around the track every day. They do some swimming, some power lifting, and various other exercises so that they can temporarily rest their more overused joints and strengthen less-used parts.”
Other non-drug approaches that may provide some modest relief include use of heat or cold packs (ask your doctor which is best for your situation), massage, and acupuncture.7 Dietary supplements such as glucosamine/chondroitin are widely marketed for joint health, but there is no clear evidence that these supplements are effective for the prevention or treatment of osteoarthritis8,9.
Medications for Osteoarthritis
Medications for osteoarthritis include over-the-counter pain relievers such as acetaminophen or ibuprofen, stronger narcotic medications, pain-relieving creams or sprays that are applied to the skin, and medications such as corticosteroids (anti-inflammatory hormones) that are injected directly into the joint. These treatments do not reverse joint damage, but they can provide temporary relief from symptoms.
Leading Cause of Disability
Arthritis and other rheumatic conditions are the leading cause of disability in the United States.10 This heading encompasses many diverse conditions, but each can take a toll on health, ability to function, and quality of life. The good news is that there are approaches to manage many of these conditions and, in some cases, to treat the underlying disease process.
The Broader Issue of Chronic Pain
Dr. Smith emphasizes that in addition to specific conditions such as RA and OA, it is important to be aware of all sources of chronic pain. “Chronic, unrelenting pain is the biggest source of disability and financial drain on the western world. We need to rethink how we see pain. The big picture is, ‘Americans hurt.’ The numbers are massive.”
A 2011 report from the Institute of Medicine estimates that each year in the United States approximately 100 million adults experience chronic pain, with annual costs between $560 billion and $635 billion.11 The report notes the need to overcome misperceptions and biases about pain and to use available tools and services to tackle the many factors that influence pain. Research into the causes and the management of chronic pain is increasing, which is good news for patients; but people who are affected by chronic pain will still need to take the initiative when it comes to reporting and seeking care for this problem.
“We’re finding very different outcomes with chronic pain versus something like spraining your ankle,” says Dr. Smith. “[Chronic pain] leads to depression; it leads to inactivity; it makes other health conditions worse. Talk to your doctor if you have a long-term pain issue, but make sure your doctor knows that it’s a long-term issue.”
Will Dietary Supplements Solve the Problem?
My local grocery store has an entire shelf devoted to glucosamine/chondroitin supplements for “joint health.” Clearly, there’s a demand for these products, but do they help? According to the research: probably not. A clinical trial published in the New England Journal of Medicine in 2006 enrolled more than 1,500 people with symptomatic osteoarthritis of the knee. Study participants—who had an average age of 59—were randomly assigned to one of five treatment groups: glucosamine, chondroitin, glucosamine and chondroitin, celecoxib (a nonsteroidal anti-inflammatory drug), or placebo. Treatment continued for six months, and the primary outcome of interest was the number of people who experienced at least a 20 percent reduction in knee pain during this time.
The results? Overall, glucosamine, chondroitin, and the combination were no more effective than placebo at reducing knee pain. Celecoxib, in contrast, did reduce knee pain. In analyses of various subgroups of patients, there was a suggestion that the combination of glucosamine and chondroitin may benefit people with the worst knee pain, but subset analyses can be prone to bias and are not considered definitive.
A 2010 combined analysis of previous studies (including the study described above) found similar results: glucosamine, chondroitin, and the combination were no more effective than placebo in people with osteoarthritis. The researchers concluded, “We believe that it is unlikely that future trials will show a clinically relevant benefit of any of the evaluated preparations.”
Kids Get Arthritis, Too
Arthritis affects an estimated 294,000 children in the United States, with the most common type being juvenile idiopathic arthritis (JIA). Idiopathic simply means that the cause is unknown. Arthritis in children is usually an autoimmune disorder, meaning that the immune system has turned against some of the body’s own tissues. As in adults, arthritis in kids often involves joint pain, swelling, and stiffness. Kids may also experience fever, a skin rash, and swollen lymph nodes. There are several different subtypes of JIA, and treatment decisions are based on the child’s individual situation. Medications that may be used include nonsteroidal anti-inflammatory drugs, disease-modifying anti-rheumatic drugs (such as methotrexate), corticosteroids, and newer biologic agents.12
1.Helmick CG, Felson DT, Lawrence RC, et al. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part I. Arthritis & Rheumatism. 2008;58(1):15-25. doi: 10.1002/art.23177.
2.Scott DL, Wolfe F, Huizinga TW. Rheumatoid arthritis. Lancet. 2010;376(9746):1094-1108. doi: 10.1016/S0140-6736(10)60826-4.
3.Hemminki K, Li X, Sundquist J, Sundquist K. Familial associations of rheumatoid arthritis with autoimmune diseases and related conditions. Arthritis & Rheumatism. 2009;60(3):661-8. doi: 10.1002/art.24328.
4.Young A, Koduri G. Extra-articular manifestations and complications of rheumatoid arthritis. Best Practice & Research: Clinical Rheumatology. 2007;21(5):907-27.
5.Lawrence RC, Felson DT, Helmick CG, et al. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States: Part II. Arthritis & Rheumatism. 2008;58(1):26-35. doi: 10.1002/art.23176.
6.Handout on Health: Osteoarthritis. National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov/health%5Finfo/Osteoarthritis Accessed December 28, 2012.
7.Vickers AJ, Cronin AM, Maschino AC, et al. Acupuncture for chronic pain: individual patient data meta-analysis. Annals of Internal Medicine [early online publication]. September 10, 2012. doi: 10.1001/archinternmed.2012.3654.
8.Clegg DO, Reda DJ, Harris CL, et al. Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis. New England Journal of Medicine. 2006;354(8):795-808.
9.Wandel S, Jüni P, Tendal B, et al. Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of the hip or knee: network meta-analysis. British Medical Journal. 2010;341:c4675. doi: http://dx.doi.org/10.1136/bmj.c4675.
10.Centers for Disease Control and Prevention. Prevalence and Most Common Causes of Disability Among Adults—United States, 2005. Morbidity and Mortality Weekly Report. 58(16); 421-26.
11.Institute of Medicine. Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education, and Research. Washington, DC: The National Academies Press; 2011.
12.Questions and Answers about Juvenile Arthritis (Juvenile Idiopathic Arthritis, Juvenile Rheumatoid Arthritis, and Other Forms of Arthritis Affecting Children. National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov/health_info/Juv_Arthritis/default.asp
. Accessed December 28, 2012.