Poor JIA prognosis more likely among Maori, Pacific Island children
Maori and Pacific Island children with juvenile idiopathic arthritis are more likely than European children to present with poor prognostic characteristics at diagnosis, despite demonstrating a significantly lower disease incidence, according to data published in Arthritis Care & Research.
“The published data regarding the incidence, clinical manifestations and severity of juvenile idiopathic arthritis (JIA) in New Zealand, particularly among Maori and Pacific children, is both sparse and outdated,” Anthony Concannon, MBChB, FRACP, of Starship Hospital in Auckland, New Zealand, told Healio Rheumatology. “The study cohort was an ethnic representation of New Zealand children from which we were able to derive an overall and ethnic incidence of JIA using current diagnostic criteria. There was an anecdotal clinician impression that JIA disease was more severe among Maori and Pacific Island children without objective evidence to support this perception.”
To determine the incidence, demographics, clinical manifestations at diagnosis and the severity of juvenile idiopathic arthritis among Maori and Pacific Island children, compared with European children, the researchers conducted a chart review of all children with the disease aged less than 16 years in the Counties Manukau, Auckland and Waitemata district health boards. Focusing on the period between January 2000 and December 2015, Concannon and colleagues identified 248 children who met the inclusion criteria, representing an overall incidence rate of 5.1 per 100,000 per year.
The researchers analyzed demographic and clinical manifestation data, and compared between ethnic groups the incidence, clinical manifestations and severity of the disease. They also noted the patients’ socioeconomic status.
According to the researchers, the incidence rate of juvenile idiopathic arthritis among European children was 7.2 per 100,000 per year — significantly greater than that of all other ethnic groups. In addition, poor prognostic characteristics were present at diagnosis in 58% of Maori and Pacific Island children, compared with 27% of those with European backgrounds (P = .0001). Maori and Pacific Island children also had significantly more poor prognostic features per child associated with JIA (P < .0001), such as oligoarticular and polyarticular disease (P < .0001). These findings were independent of socioeconomic status.
Significant prognostic features included cervical involvement, present in 25% of Maori and Pacific Island children, and in 9% of European children (P = .03); erosive changes, present in 22% of Maori and Pacific Island children and 8% of European patients (P = .05); joint space narrowing, in 13% of Maori and Pacific Island children compared with 2% of European children (P = .02); and polyarticular rheumatoid factor positive disease, present in 47% of Maori and Pacific Island children and 14% of European children (P = .01).
“These findings suggest that although JIA is more common in European children, Maori and Pacific Island children are more likely to present with features suggestive of a worse outcome,” Concannon said. “Clinician awareness of these potential differences may influence baseline screening, monitoring and treatment. Maori and Pacific children face access to health care barriers, including socioeconomic factors, which may contribute to both a lower incidence and higher severity of JIA at diagnosis.”
Concannon later added, “However, even when adjusting for socioeconomic status, the differences between Maori and Pacific and European children presenting with poor prognostic features remained significant. This implies that other ethnic specific factors, including genetic variability, may contribute to prognostic features at JIA diagnosis.” – by Jason Laday
Disclosure: Concannon reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.