While it isn't nearly as recognizable as its cancerous kin, the lung disease sarcoidosis has become increasingly prevalent in recent years, a new study has found.
In fact, researchers from the Department of Radiology at the Ohio State University College of Medicine say that rates of the disease -- which causes tiny clumps of abnormal tissue (granulomas) to form in certain organs of the body, resulting in inflammation in the lymph nodes, lungs, liver, eyes, skin, or other tissues -- have more than doubled in the 15 years leading up to their study.
Examining medical records of 1.48 million patients in Franklin County, Ohio, a demographic profile that they say is nearly identical to that of the U.S., the study authors found that the prevalence of sarcoidosis increased steadily from 164 in 100,000 in 1995 to 330 in 100,000 in 2010. Their findings were published this month in the journal Respiratory Medicine.
Comedian Bernie Mac's death in 2008 shed some light on sarcoidosis. Mac suffered from a compromised immune system as a result of his battle with the disease, though it was in remission at the time of his death, his sister-in-law told People magazine.
Last year, actress Tisha Campbell-Martin responded to rumors that she was dying from sarcoidosis, telling People that she'd had the disease for nearly 10 years. "I was diagnosed with a lung disorder that some people walk around with and don’t even know they have," she said.
According to the National Heart, Lung and Blood Institute, the cause of sarcoidosis is unknown. What is known, however, is that the condition is more common among African Americans than whites and tends to develop between the ages of 20 and 40.
Doctors also believe that there's a genetic factor at play, since people who have a close blood relative with sarcoidosis are nearly five times as likely to develop the disease, according to the National Institutes of Health.
How sarcoidosis develops is also clear:
Normally, your immune system defends your body against foreign or harmful substances. For example, it sends special cells to protect organs that are in danger.
These cells release chemicals that recruit other cells to isolate and destroy the harmful substance. Inflammation occurs during this process. Once the harmful substance is gone, the cells and the inflammation go away.
In people who have sarcoidosis, the inflammation doesn't go away. Instead, some of the immune system cells cluster to form lumps called granulomas (gran-yu-LO-mas) in various organs in your body.
The researchers at Ohio State say the two-fold increase in sarcoidosis prevalence they observed is primarily related to improved detection and diagnostic approaches.
A study of sarcoidosis among women participating in the Black Women’s Health Study conducted last year by researchers from Boston University found the disease caused 25 percent of all deaths among women who had it. But others say the disease is rarely fatal.
"In half the cases, sarcoidosis heals naturally -- without any treatment," the American Lung Association maintains.