, a retrospective cohort study has determined.
“The incidence rate and risk factors of psoriasis in children with IBD [inflammatory bowel disease], JIA [juvenile idiopathic arthritis], or CNO [chronic nonbacterial osteomyelitis] who are exposed to TNFi [tumor necrosis factor inhibitors] are unknown. Additionally, there is a well-established association between these inflammatory conditions and psoriasis development. Yet, as TNFi can both treat and trigger psoriasis, it is not clear how TNFi exposure affects this relationship,” wrote Lisa H. Buckley, MD, of Children’s Hospital at Vanderbilt, Nashville, Tenn., and colleagues. Their report is in Arthritis Care & Research.
The team examined the relationship in children who were treated for an inflammatory disorder at Children’s Hospital of Philadelphia during 2008-2018. IBD was most common at 74%, followed by JIA at 24% and CNO at 2%.
Among 4,111 children with those inflammatory disorders, the psoriasis incidence was 12.3 per 1,000 person-years in exposed children and 3.8 per 1,000 person-years in unexposed. This significant difference equated to a hazard ratio of 3.84 for developing psoriasis after TNFi exposure.
“These data reflect the established association between inflammatory conditions and psoriasis development and suggest that TNFi exposure further increases the risk of psoriasis,” Dr. Buckley and coauthors wrote.
The median duration of follow-up in this study was about 2.5 years for patients exposed to TNFi and 2 years for those unexposed. Among the entire cohort, 39% had been exposed to a TNFi, with 4,705 person-years of follow-up. Among the unexposed children (61%), there were 6,604 person-years of follow-up.
In all, 83 cases of psoriasis developed: 58 in the exposed group and 25 in the unexposed group. Psoriasis incidence varied by disorder. Exposed children with IBD had a higher incidence than did unexposed children (10.9 vs. 2.6 per 1,000 person-years; HR = 4.52). Exposed children with JIA also had a higher incidence than did unexposed children (14.7 vs. 5.5 per 1,000 person-years; HR = 2.90). Among those with CNO, incidences were similar for exposed and unexposed children (33.5 and 38.9 per 1,000 person-years).
A family history of psoriasis significantly increased the risk of psoriasis with a hazard ratio of 3.11, the authors noted. But none of the other covariates (age, sex, race, obesity, methotrexate exposure, and underlying diagnosis) exerted a significant additional risk.
The study had no outside funding source. The authors had no financial disclosures. Dr. Buckley conducted the research when she was a pediatric rheumatology fellow at Children’s Hospital of Philadelphia.
SOURCE: Buckley LH et al. Arthritis Care Res. 2019 Oct 23. doi: 10.1002/ACR.24100