How common is juvenile rheumatoid arthritis?
About 1 in 1,000 children have juvenile rheumatoid arthritis (JRA).1 There are three types of juvenile rheumatoid arthritis. Pauciarticular JRA (also known as oligoarthritis) and polyarticular JRA (also known as polyarthritis) are most common in girls. Systemic JRA is equally common in boys and girls.2
The three types of JRA affect children at the following rates:3
- About 60% of all children with JRA have pauciarticular symptoms during the first 6 months. While as many as 1 in 5 of these children goes on to develop polyarticular symptoms, most continue to have less than 4 joints affected over time.4
- About 30% of all children with JRA have polyarticular symptoms.
- About 10% of all children with JRA have systemic symptoms.
Juvenile rheumatoid arthritis can occur at higher rates among certain ethnic groups as well as in some geographic areas. Environmental and genetic factors are thought to be responsible, though researchers have yet to confirm this theory.4
- In the United States, children of African or European descent have similar rates of JRA.
- Some Native American populations have increased rates of JRA. In British Columbia, Canada, Native American children are over 3 times more likely to develop JRA than children of European descent in the same geographic area.
| Author: | Shannon Erstad, MBA/MPH | Last Updated: June 30, 2006 |
| Medical Review: | Michael J. Sexton, MD - Pediatrics Ross E. Petty, MD, PhD, FRCPC - Pediatric Rheumatology | |
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