The interplay between pain and disease activity: personal models of pain beliefs and emotional representations in children and young people with juvenile idiopathic arthritis in a UK nationwide prospective inception cohort.

objectivesJuvenile idiopathic arthritis (JIA) is a group of childhood-onset inflammatory rheumatic conditions characterized by pain as one of the most common and distressing symptoms. This cross-sectional study aimed to investigate whether relationships between reported pain and disease activity in JIA affected beliefs about pain, known as "personal models."

methods187 out of a possible 363 participants with JIA who completed questionnaires about function and pain perception were recruited through the Childhood Arthritis Prospective Study (CAPS). A pre-selected pain score threshold and validated disease activity score cut-offs were used to assign the participants into four groups: low pain/low disease, low pain/high disease, high pain/low disease, and high pain/high disease. Multivariable linear regressions examined associations between the groups and their "personal models."

resultsCompared to participants with low pain/low disease, those with high pain/high disease and those with high pain/low disease were more likely to sense greater threat, have more negative emotional representations, and perceive less control over their pain. Participants with low pain/high disease had similar pain beliefs compared to those with low pain/low disease.

conclusionThis is the first study to compare "personal models" of pain in JIA. Children and young people who experience high pain severity regardless of disease activity perceived high pain threat, low controllability, and negative emotional representations. This highlights the importance of considering and addressing personal models of pain at diagnosis, especially those who present high levels of pain.