Eye inflammation tends to occur around the same time as arthritis flares in children with juvenile idiopathic arthritis (JIA), a new study indicates.
This finding suggests that JIA patients’ eyes should be assessed when they experience arthritis flares.
The study, “The temporal relationship between juvenile idiopathic arthritis disease activity and uveitis activity,” led by researchers at the Children’s Hospital of Philadelphia (CHOP), was published in the journal Arthritis Care & Research.
Uveitis, a type of eye inflammation, is a symptom experienced by some people with JIA. While uveitis does not always manifest itself with overt symptoms — often, an eye examination is required for diagnosis — it can cause problems such as cataracts and glaucoma, which can lead to blindness if left untreated.
Although prior research associated JIA with such eye inflammation — juvenile idiopathic arthritis accounts for more than 20% of all non-infectious uveitis cases — little is known about the temporal relationship between the two conditions. In other words, it is not clear whether JIA and uveitis tend to flare up at the same time.
“Identification of such relationship would inform management of children with known JIA-U [JIA-associated uveitis], as an arthritis flare would prompt immediate referral for assessment of uveitis activity,” the researchers wrote.
To assess whether such a relationship existed, the team of researchers analyzed patient data for 98 children treated for JIA-U at CHOP between 2013 and 2019. Among this group, 82% were girls and 60% had oligoarticular JIA, both the mildest and most common form of the disease. The median age at uveitis diagnosis was 5.1 years, and at JIA diagnosis was 3.3 years. In turn, the median age at the patients’ healthcare visits was 10.9 years.
Over the analyzed time period, these patients attended a total of 1,229 rheumatology-focused hospital visits — a median of 13 visits per patient. Arthritis was active in 17% of these visits.
As for treatment, 70% of patients received at least one biologic disease-modifying anti-rheumatic drug (DMARD), while 83% were given a conventional DMARD; 65% received a combination therapy.
For 947 of the rheumatology visits, the patients had an eye exam on record within 45 days, either before or after the rheumatology appointment. At 694 of these visits (73%), the status of JIA was the same as that of uveitis. Specifically, both JIA and eye inflammation were active in 69 visits (6%), while both were inactive in 625 visits (51%).
“To date, this is the largest investigation evaluating the temporal association between arthritis activity and uveitis activity in a cohort of patients with JIA-U,” the scientists wrote.
Statistical models suggested that a person with JIA and active arthritis is about 2.5 times more likely to have active uveitis, compared with a patient without arthritis flares. The probability that a person with active JIA had active uveitis within 45 days was 65%, which compared with 42% in patients with no active joints.
Additional analyses showed a lower risk of uveitis among girls and those treated with a combination of biologic and conventional medications. The uveitis risk also was found to be higher for children with oligoarticular JIA than for all other subtypes apart from psoriatic JIA. These data are broadly in agreement with previous findings.
“This novel work has demonstrated an independent temporal association between uveitis and arthritis activity in patients with JIA-U,” the investigators wrote, noting that the children were 2.5 times more likely to have eye inflammation at the same time as arthritis flares.
“This important finding challenges the prior paradigm that uveitis runs a separate course from arthritis,” they wrote.
Based on these findings, the researchers said “an arthritis flare in patients of all JIA subtypes should prompt expedited uveitis screening.”