Psoriasis and associated variables in classification and outcome of juvenile idiopathic arthritis - an eight-year follow-up study

Background: to study the impact of psoriasis and features associated with psoriasis on classification and outcome in a population-based follow-up cohort of children with juvenile idiopathic arthritis (jia). methods: in all,440 children with jia were followed for a median of 8 years in a prospective nordic population-based cohort study. data for remission was available for 427 of these children. the presence of psoriasis,psoriasis-like rash,dactylitis,nail pitting,enthesitis,tenosynovitis and heredity was assessed in relation to ilar classification and remission. results: clinical findings associated with psoriasis developed consecutively during the 8-year period. six of 14 children with psoriasis were not classified as juvenile psoriatic arthritis according to the ilar criteria at 8 year follow-up. dactylitis was more common in children with early onset of jia. after 8 years we found a cumulative median number of eleven arthritic joints in children with psoriasis or psoriasis-like rash compared with six in the rest of the cohort (p=0.02). also,the chance for not being in remission after 8 years increased significantly in patients with psoriasis,psoriasis-like rash or at least two of: 1) first-degree heredity for psoriasis or psoriatic arthritis,2) dactylitis or 3) nail pitting,compared with the rest of the group (or 3.32,p=0.010). conclusions: our results indicate a more severe disease over time in psoriasis-associated jia,as features of psoriasis develop during the disease course. this group is a major challenge to encompass in a future jia classification in order to facilitate early tailored treatment. © 2017 the author(s).