Exploring pain catastrophizing and its associations with low disease activity in rheumatic inflammatory disorders.

Pain catastrophizing is a maladaptive mechanism associated with the exaggerated experience of pain, increased rumination and feelings of helplessness. The main objective of this study was to explore whether increased pain catastrophizing is independently associated with a lower proportion of low disease activity (LDA) in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondylarthritis (axSpA). Demographics, comorbidities, treatment, disease activity measures and patient-reported outcome data were recorded in RA, PsA and axSpA patients. Pain catastrophizing score (PCS) was assessed using a standardised questionnaire. For each diagnosis, composite disease activity scores with distinct cut-off values for LDA, i.e. DAS28-CRP (RA), DAPSA (PsA) and ASDAS-CRP (axSpA) were calculated and used as the dependent variable in logistic regression reflecting LDA achieved. A total of one thousand two hundred and twenty nine patients were included: 580 with RA, 394 with PsA and 255 with axSpA. In the multivariable analysis, pain catastrophizing was independently associated with LDA rates in axSpA (OR 0.33, 95% CI [0.12, 0.88]) amongst tested groups. In RA (OR 0.90, 95% CI [0.64, 1.28]) and PsA (OR 0.77, 95% CI [0.55, 1.07]), a statistically significant association was not observed. Higher PCS was independently associated with not achieving LDA in axSpA. Our data, however, indicate that pain catastrophizing, which also reflects a patient's personality traits and coping abilities, plays a less important role for the patient than general pain perception.