Systemic Arthritis and Prolonged Corticosteroid Use Associated with Growth Impairment in Juvenile Idiopathic Arthritis

Systemic Arthritis and Prolonged Corticosteroid Use Associated with Growth Impairment in Juvenile Idiopathic Arthritis

A recent study showed that children with juvenile idiopathic arthritis (JIA) now have similar growth and weight gain as children in the general population. Nonetheless, about 1 in 10 JIA children with systemic arthritis, uncontrolled disease, or prolonged use of corticosteroids had an increased risk of growth impairment.

The findings were reported in a study titled, “Growth and weight gain in children with juvenile idiopathic arthritis: results from the ReACCh-Out cohort,” published in the journal Pediatric Rheumatology

JIA is one of the most common rheumatic disorders affecting children and is known to influence a child’s growth and weight gain. It is believed that modern treatments have improved growth in children with JIA.

To confirm this hypothesis, researchers analyzed data from a program called “Research in Arthritis in Canadian Children emphasizing Outcomes,” or ReACCh-Out, with JIA patients diagnosed for the first time between 2005 and 2010 at 16 Canadian pediatric rheumatology centers. In total, 1,147 children were included in the study and followed for a median of 35.5 months.

Weight and height measurements were taken every six months for two years, and then every year for up to five years.

Age- and sex-standardized scores were calculated for weight, height, and body mass index (BMI) using Canadian Pediatric Endocrinology Group standards. Data on disease activity and medication used were collected by a pediatric rheumatologist at each visit and in-between study visits.

Overall, researchers found that mean scores for height, weight, and BMI remained relatively the same for the entire group. In total, 33 children (2.9%) developed a short stature, while 27 (2.4%) had a tall stature.

Of the children with systemic arthritis, which affects the entire body, 9.3% had an estimated three-year cumulative incidence of short stature, and 34.4% were obese.

The majority of children studied (81.7%) received no corticosteroids as treatment. However, 1 mg/Kg/day prednisone-equivalent (prednisone is a corticosteroid) treatment for six months led to a reduction of 0.64 in height scores, and an increase of 0.74 in BMI scores.

The incidence of short stature in children with prolonged steroid use was 6.6% in three years, compared with 2.6% in those not using steroids. The incidence of obesity also was higher, at 25% in three years for prolonged steroid users compared with 8.5% in non-users.

“Most children in this modern JIA cohort grew and gained weight as children in the general population. About 1 in 10 children who had systemic arthritis, uncontrolled disease and/or prolonged corticosteroid use, had increased risk of growth impairment,” the team stated. “These children may benefit from earlier aggressive therapy to help prevent growth impairment, or early consultation with a pediatric endocrinologist to mitigate growth impairment by other means.”