Who develops scleroderma, and when?
It’s estimated that about 300,000 Americans have scleroderma. About one third of those people have the systemic form of scleroderma. Since scleroderma presents with symptoms similar to other autoimmune diseases, diagnosis can be difficult. There may be many misdiagnosed or undiagnosed cases.
Localized scleroderma is more common in children, whereas systemic scleroderma is more common in adults. Overall, females with scleroderma outnumber males about 4-to-1. Other factors such as race and ethnic background, may determine the risk of getting scleroderma, the age of onset, and the pattern or severity of internal organ involvement. The reasons for this are not clear. Although scleroderma is not directly inherited, some scientists feel there is a slight predisposition to it in families with a history of rheumatic diseases.
Scleroderma can develop in every age group from infants to the elderly, but its onset is most frequent between the ages of 25 to 55. When doctors say “usually” or “for the most part,” the reader should understand that variations frequently occur. Many people get alarmed when they read medical information that seems to contradict their own experiences, and conclude that what has happened to them is not supposed to happen. There are many exceptions to the rules in scleroderma, perhaps more so than in other diseases. Each case is different, and information should be discussed with your own doctor.
In African American individuals, the incidence of systemic sclerosis is higher than it is in non-African Americans. Among all African Americans, 23.7 people per million are diagnosed with systemic sclerosis, while the comparable rate among non-African Americans is 18.3 people per million diagnosed. We see a similar pattern when looking at the prevalence of systemic sclerosis among African-Americans contrasted with non-African-Americans.
The progression of the disease in African Americans can be different than in non-African Americans due to differences in autoantibodies. Generally speaking, African American are diagnosed at a younger age than non-African Americans are diagnosed. Additionally, African Americans far more frequently have the diffuse cutaneous form of systemic sclerosis and are more likely to have lung and other organ involvement than occurs among non-African Americans.