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Autoimmune Update: Cracking the Code
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Unraveling the mysteries as we learn how to protect the body against itself
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By Meryl Davids Landau
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MediZine's Healthy Living First Quarter 2006
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Imagine a highly trained police squad mistakenly marking innocent citizens as shooting targets, and you begin to understand both the seriousness and the sadness of autoimmune diseases (ADs). For reasons still not clear, the brilliant and complex immune system occasionally goes after the body’s own healthy cells. This “friendly fire” results in more than 80 distinct ADs, with symptoms ranging from rashes and fatigue to pain and debilitation.
Collectively, ADs affect 5 to 8 percent of Americans, and occurrences seem to be on the rise. “This may be because both doctors and patients are becoming more aware, but the incidence of some autoimmune diseases, especially multiple sclerosis and type 1 diabetes, truly is increasing,” says Noel Rose, M.D., Ph.D., director of AD research at Johns Hopkins University in Baltimore. While ADs continue to baffle, experts are optimistic that better diagnoses, treatments and understanding are on the way.
Blame your genes for about a third of your risk of developing an autoimmune disease. (ADs tend to cluster in families, but relatives can develop different diseases, with a mother having, say, type 1 diabetes, while her daughter has Graves’ disease.) The other two thirds? Experts aren’t sure, but research points to possible triggers in susceptible individuals, such as hormones and the following:
Viruses/bacteria
These are implicated in the number one theory. “Infection sets the immune system in motion, and the susceptible system can’t turn itself off, eventually changing targets from germs to host,” explains Jane E. Salmon, M.D., codirector of the Kirkland Center for Lupus Research at New York City’s Hospital for Special Surgery.
Nutrient deficiencies
Preliminary research links certain conditions, such as Hashimoto’s thyroiditis, with a lack of selenium or too much iodine.
Environmental contaminants
A recent small study at the University of Montana found that residents in an asbestos-polluted town were significantly more likely to have antibodies indicating an auto-immune reaction than those in a control group. However, “This very controversial area still needs a lot more research,” Dr. Rose cautions.
Chronic inflammation
Experts are looking at the possibility that some people suffer from constant low-grade inflammation (as opposed to the acute bouts needed to heal an injury) and that this can lead to various health consequences, including ADs.
Hashimoto’s thyroiditis
This disorder causes the immune system to attack the thyroid gland. The result is reduced thyroid hormone levels—and fatigue, constipation and more. Treatment involves daily thyroid hormone replacement. Number of cases nationwide: 14 million.
Graves’ disease
Antibodies bind to the surface of thyroid cells, causing hormone overproduction. In some, swelling around the eyes causes a characteristic bulge. Medications can reduce levels of these hormones; surgery or radioactive iodine can eliminate or shrink the gland. Number of cases nationwide: 13 million.
Vitiligo
In this disease, white patches appear where pigment-making cells have been destroyed. Medical or surgical treatments aim to restore pigmentation and improve skin function and appearance. Number of cases nationwide: 2 to 5 million.
Rheumatoid arthritis (RA)
In RA, the immune system turns on the lining, or synovium, of the joints and can also affect the heart, lungs and eyes. Treatment includes rest, exercise and medications. While RA can be debilitating, Danish researchers recently found that sufferers today typically face a more mild progression than that faced by those who had it decades ago; this is likely due to aggressive early treatment. Number of cases nationwide: 2.1 million Americans (71 percent of them women).
Type 1 diabetes
Unlike the lifestyle-induced type 2, this form of diabetes results when the body destroys insulin-producing cells in the pancreas. Tightly controlling blood sugar via insulin injections or pumps can minimize serious complications. Number of cases nationwide: 1.5 million.
Hope for the Future
Some autoimmune disorders are treated by replacing the relevant missing hormone (taking insulin for example). But many can be helped only by suppressing the wayward immune system, a process that can lead to severe side effects and increased risk of serious infection. Part of the problem is that many of today’s drugs for ADs are old.
Fortunately, things are beginning to change. “There hasn’t been a new medication approved for the prototypical autoimmune disease, lupus, in thirty years. But now more than ten drugs are currently being tested,” says Dr. Salmon. Scientists are also excited about research into biomarkers. These may indicate which medications will work best for an individual. Biomarkers may even show whether a person without an autoimmune disease is at risk for one and should start treatment before symptoms appear.
BLURB 1: Gender Bias
Though a few ADs strike the genders equally, about 75 percent of cases occur
in females.
One key reason: Hormones, especially estrogen. Women with multiple sclerosis or rheumatoid arthritis often see symptoms improve during pregnancy. Still other autoimmune conditions don’t appear until after menopause. And a recent study found the incidence of MS was 40 percent lower in women who had used oral contraceptives during the previous three years.
Other factors: Cells left behind by a fetus may recognize the mother’s antigens as foreign and attack them, triggering an AD. And women have more elaborate immune systems. “It must be complex enough to prevent her rejecting a baby, but that means there is more that can go wrong,” says Robert Lahita, M.D., Ph.D., author of Women and Autoimmune Disease.
BLURB 2: RA + Diet
Hungry? Why not opt for a salad chock-full of yellow and orange peppers, or a fruit cup with bananas and oranges? A diet that includes a modest increase in yellow and orange veggies and fruits—an increase equivalent to just one glass of orange juice a day—may cut your risk of developing inflammatory diseases like RA, according to a new British study of more than 25,000 people who were monitored for nine years.
What makes these fruits and veggies so powerful? Research points to vitamin C and the pigment beta-cryptoxanthin. Both are found in brightly colored produce; they appear to act as antioxidants, which protect the body against the oxidative damage that can cause inflammation.
—Gabrielle Lichterman
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