September 18, 2000

A Health Center researcher has found that if autoimmune diseases were counted as a single category instead of more than 20 separate illnesses, they would move on to the federal government's list of the 10 most common causes of death for women younger than age 65.

The researcher, Stephen J. Walsh, an assistant professor in the Department of Community Medicine and Health Care, reported his findings in the September issue of the American Journal of Public Health.

"Most of us know someone with an autoimmune disease, we just didn't know that the 'rare' condition they have is part of a large group of similar diseases that afflict a relatively large segment of the population," Walsh says. "Despite their common occurrence, the autoimmune diseases have not received the attention they deserve from public health officials because, taken as individual diseases, they didn't seem all that common."

Autoimmune diseases, a broad class of illnesses affecting the immune system, include rheumatoid arthritis, lupus, multiple sclerosis, scleroderma and juvenile diabetes, among others. Medical researchers have shown that at least 20 different diseases involve autoimmune processes, and they are currently investigating the possibility that another 40 might do so.

An autoimmune disease is an illness caused by a person's own immune system attacking some part of the body - for example, the heart, kidneys, joints, or skin. Over time, the immune system permanently damages and disables the structure under attack, leading to chronic disease and, often, to death.

An autoimmune disease is the opposite of AIDS. AIDS involves a deficient immune system that cannot fight off infection. An autoimmune disease occurs when the immune system is overactive, to the degree that it is harmful in the absence of any infection, Walsh says.

He says new research shows that, as a class, autoimmune diseases are a significant source of illness, disability, and death. He points to a study that estimated the number of people in the United States with an autoimmune disease. The study concluded that, for women, the number is about 1 in 20. This demonstrates, he says, that only by studying these similar diseases as a group can we come to appreciate their impact on public health.

Why the diseases affect women the way they do is one of the "big" research questions that remain to be answered, Walsh says. The fact is that, in adults, the major autoimmune diseases occur more often in women than men. For example, multiple sclerosis occurs twice as often in women and lupus occurs six to seven times more often. More frequent occurrence among women is one of the most evident characteristics of autoimmune diseases, he says, but scientists still have little understanding of why that's the case.

The government's list of the most common causes of death is an annual compilation of how people die, broken down by demographic characteristics. The primary causes of death for women under 65 include heart disease, cancer, stroke, AIDS, accidents, suicide and homicide.

Walsh suggests additional resources should be committed to investigatin g autoimmune diseases - both the causes and potential cures. He specifically points to the need for regional registries of people diagnosed with autoimmune diseases. "No single hospital or university has enough patients with any one autoimmune disease to support effective evaluation of causes or treatments," he says. "The creation of regional registries for cancer patients started in Connecticut in the 1930s and has had an enormous impact on our understanding of that disease. With a modest level of federal support, a similar program could be initiated for the autoimmune diseases."

Pat Keefe