A Better Understanding of Autoimmune Diseases

The immune system is your body's first line of defense against foreign invaders, including viruses, germs and other harmful bacteria. When it detects a threat, it releases antibodies to attack and eradicate it. However, certain disorders can disrupt the immune system, causing it to mistake healthy cells as intruders.

Autoimmune diseases affect about 8 percent of the population and are the third leading category of disease in the U.S. after cancer and heart disease. About 78 percent of people with autoimmune diseases are women.

There are more than 100 autoimmune diseases affecting various parts of the body, including the joints, muscles, skin, nervous system, digestive system and glands. Some conditions target one body part, while others impact multiple areas or even the entire body.

There is no cure for most autoimmune disorders, nor do researchers know what causes them.

Some of the most common autoimmune diseases are:

• Celiac disease
• Type 1 diabetes
• Inflammatory bowel disease (IBD)
• Multiple sclerosis (MS)
• Grave's disease
• Lupus
• Rheumatoid arthritis
• Psoriasis
• Hashimoto's thyroiditis
• Alopecia
• Pernicious anemia
• Sjögren syndrome
• Reactive arthritis
• Myasthenia gravis
• Addison's disease

Why women are at greater risk

Research indicates women are about twice as likely as men to develop autoimmune diseases. Women are also more likely to develop multiple disorders. Experts aren't sure of why for either, but the prevailing theory is that a combination of hormones, genetics and immune system response is to blame.

Estrogen, a hormone found in higher proportions in women than in men, is one potential culprit. The hormone tends to increase inflammation, an immune response that can backfire and exacerbate or cause many common ailments. Conversely, testosterone, a hormone men have significantly more of, tends to keep the body's inflammatory response in check.

Hormonal changes may come into play, too. Most women are diagnosed with autoimmune conditions during significant hormonal transition periods, such as puberty, childbearing years and pregnancy, and menopause. Men don't go through as many significant hormonal changes as women, which may reduce their risk.

Genetics is another factor. The X chromosome, of which women have two and men one, produces a larger number of genes than the Y chromosome, increasing the potential for mutations. For example, one study found the gene Kdm6a on the X chromosome was expressed more in women's immune systems than in men's. Researchers hypothesize this gene may be linked to women's increased likelihood of developing multiple sclerosis.

Symptoms of an autoimmune disease

Because there are so many autoimmune diseases affecting different body areas, there is also a vast array of symptoms, which can vary significantly from one disorder and person to another. However, many diseases share certain symptoms, such as:

• Joint pain, inflammation or swelling
• Skin problems, such as a rash
• Digestive issues, such as constipation
• Abdominal pain
• Fatigue
• Swollen glands, especially in the neck
• Fever

If you notice any changes in your body or health, it's important to talk to your doctor. If they suspect you may have an autoimmune condition, they may refer you to a rheumatologist or allergist/immunologist, doctors who specialize in the immune system.

Your healthcare team may include other specialists, such as an endocrinologist, who can assist in treating hormone-related autoimmune conditions, such as Hashimoto's thyroiditis.

Together, you and your medical providers can determine the best course of action depending on your condition type and severity. Treatments can vary widely but often include diet or lifestyle changes and over-the-counter or prescription medications. Often, treatment focuses mainly on bolstering the immune system and reducing inflammation, along with mitigating symptoms.