Accelerometer-assessed daily physical activity in relation to pain cognition in juvenile idiopathic arthritis

Objectives: Pain has been known to predict low physical activity (PA) in juvenile idiopathic arthritis (JIA) and high levels of pain are related to maladaptive coping rather than disease severity. Objectively monitored PA in JIA has recently been shown not to be related to pain intensity, emphasizing the need to explore pain more deeply. The aim of this study was to examine accelerometer-assessed PA in relation to pain cognition in children with JIA.

Method: Data gathered included disease activity, functional ability, and pain cognition. PA was monitored with a GT1M Actigraph accelerometer.

Results: Sixty-one patients were included. Disease activity, functional impairment, and pain intensity scores were relatively low. Accelerometry was correlated positively to the specific belief of having control of pain (‘Control’) but negatively to disease activity. There was no correlation with functional ability, pain intensity, coping strategies, or other pain beliefs. When isolated, disease activity (measured by the 27-joint count Juvenile Arthritis Disease Activity Score, JADAS-27) contributed significantly to the variance in accelerometry, while ‘Control’ could not significantly explain a unique part of the variance.

Conclusions: Objectively measured PA was negatively correlated to disease activity but not to pain intensity. The only pain cognition measurement to reach higher levels of PA was to be in control of pain.