Rheumatic diseases, such as juvenile idiopathic arthritis (JIA), are typically associated with acute pain mainly caused by inflammation. Chronic pain is described as pain lasting at least 3 months. In JIA patients chronic pain may occur despite successful treatment. Chronic pain and pain disorders frequently occur during the course of the disease despite successful control of inflammation.
Possible interrelations between JIA and pain disorders are presented.
Besides a review of the available literature, a retrospective cohort study was conducted, including 906 patients with a chronic pain disorder with somatic and psychological factors (CPD) and/or a complex regional pain syndrome type I (CRPS I). The frequency of pre-existing rheumatic illnesses was analyzed.
The JIA is a risk factor for the development of a CPD. Especially polyarticular, extended oligoarticular, enthesitis-associated JIA and psoriatic arthropathy were found to be significantly associated with an increased risk for developing CPD. In contrast, an increased risk for development of CRPS I was not observed.
Our study demonstrates JIA to be a risk factor for the development of chronic pain not only as a result from malpositioning or arthrosis but also as a chronic pain disorder (CPD). Further studies are necessary to clarify the relevance of disease activity and duration and also of psychological factors for the pathogenesis.

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