A study published in ACR Open reported an increased psychiatric morbidity burden in patients with juvenile idiopathic arthritis (JIA) compared with both the general population.
The researchers conducted an observational, registry-based study of data from between July 2006 and December 2020 in Sweden. Three study populations were identified: patients with incident JIA, who were compared to age- and sex-matched individuals from the general population; patients with incidence JIA, who were compared to full, same-sex siblings; and patients with prevalent JIA at age 18 who were compared to matched general population individuals. The prevalence of 6 groups of psychiatric disorders were examined: mood and anxiety, suicidal behavior, eating, sleeping, substance use, psychotic, and an overall combined outcome (ie, at least one of six).
In total, 4,939 patients with incident JIA were included, with 25,141 person-years of follow-up. In the population of patients with incident JIA compared with the general population, the incidence of the overall combined outcome for psychiatric disorders was 20.1 per 1,000 person-years (versus 13.1 per 1,000 person-years in the general population; hazard ratio [HR]=1.49). Sleeping disorders, suicidal behavior, and mood and anxiety disorders had the highest HRs in this population (1.91, 1.60, and 1.46, respectively). Overall, patients with JIA had increased incidence rates for all 6 psychiatric outcomes than the general population. The researchers noted that some of the covariates used for adjustment were significantly associated with the outcome—for example, a family history of any psychiatric disorder was associated with an HR of 1.86 for the combined outcome.
When compared with siblings, patients with incident JIA also had a higher HR for overall combined outcomes (1.16), though this figure was not statistically significant. HRs for specific psychiatric disorders were also not statistically significant in this subgroup, with estimates close to 1 for suicidal behavior.
In the cross-sectional analysis of 3,717 patients with prevalent JIA at age 18, these patients were more likely to have been diagnosed with a psychiatric disorder than matched general population peers (odds ratio=1.37). By age 18, 18.4% had been diagnosed with a psychiatric disorder, compared with 14.1% in the general population. Elevated HRs were noted for neuropsychiatric disorder, mood and anxiety disorder, suicidal behavior, and eating disorder.
A sensitivity analysis found that incidence rates were globally lower for both patients with JIA and the general population when excluding individuals with a history of psychiatric disorders, but this did not impact HRs. HRs also remained similar when follow-up was extended beyond age 18. The authors noted that the extent to which increased incidence of psychiatric disorders reflects the psychosocial consequences of JIA is unclear based on these findings.
Overall, the authors summarized that “patients with JIA are at increased risk of developing psychiatric disorders, resulting in an increased burden of psychiatric comorbidities, both in childhood and when reaching adulthood. Importantly, our study showed that the risk was not restricted to patients with JIA in families with a history of psychiatric disorder, yet our results are compatible with the existence of shared familial risk factors between JIA and psychiatric disorders.”