Unlike osteoarthritis, which results from wear and tear in the joints, rheumatoid arthritis is an autoimmune disease. This means it occurs when the body becomes inflamed and attacks itself against what it perceives to be a threat. Studies have shown that people with one autoimmune disease often are at risk of having another one (or even more than one). So if you've got rheumatoid arthritis, are you destined to develop other autoimmune conditions down the road? Or vice versa? You just might. Below is a rundown of various autoimmune diseases and their connection with arthritis:

Type 1 diabetes. Type 1 diabetes shares a definite link to rheumatoid arthritis. In fact, research indicates that people with diabetes are almost two times as likely to also have rheumatoid arthritis. The two conditions share some of the same markers, including joint damage. In diabetes, inflammation causes the body to be unable to make or use insulin properly. This can lead to nerve damage that ultimately damages joints much like rheumatoid arthritis does. One piece of good news: Because the diseases are both autoimmune conditions and share some of the same symptoms, certain medications used to treat rheumatoid arthritis may be effective in people with diabetes.

Lupus. This autoimmune condition is known as a connective-tissue disease, as rheumatoid arthritis also is. Both diseases hit women much more often than men, may affect multiple organs in the body, and share certain symptoms. Lupus sufferers experience inflammation that can affect various areas of the body simultaneously and cause joint pain.

Sjogren's syndrome. Sjogren's syndrome is a disease that involves a lack of moisture. It often causes dryness in the mouth and eyes as well as the nose, throat, and skin. About half of all people with Sjogren's syndrome also have another connective-tissue disease such as rheumatoid arthritis or lupus. Since dry or burning eyes may also be one sign of rheumatoid arthritis, people with this symptom may very well have both autoimmune conditions.

Celiac disease. An autoimmune disorder thought to affect up to 1 percent of the population, it is characterized primarily by the intestines attacking themselves in response to the affected person eating wheat or other forms of gluten. At least one small study in Sweden discovered that cutting out animal products and gluten helped a group of rheumatoid arthritis sufferers feel better, something many rheumatoid arthritis patients have discovered on their own. Celiac disease sufferers usually experience a complete reversal of intestinal damage (and often reduce the disease's other symptoms, which can include neurological difficulties) when they eliminate gluten.



Celiac Disease Foundation, www.celiac.org

Arthritis Foundation, www.arthritistoday.org

National Institutes of Health, www.nlm.nih.gov