Comparison of chronic widespread pain prevalence with different criteria in two cohorts of rheumatoid arthritis
Abstract Objective This study aims to investigate chronic widespread pain with the 1990 (CWP1990) and 2019 (CWP2019) definitions 6 years after the onset of rheumatoid arthritis (RA), in one patient cohort with tight controls and one conventional cohort, and factors associated with reporting CWP1990 and CWP2019, respectively. Methods A cohort of 80 RA patients with monthly visits to the physician the first 6 months was compared to a cohort of 101 patients from the same clinic with conventional follow-up. Both cohorts had early RA (< 13 months). The prevalence of CWP1990 and the more stringent CWP2019 were in a 6-year follow-up investigated with a questionnaire, including a pain mannequin and a fear-avoidance beliefs questionnaire. Results In the tight control cohort, 10% reported CWP2019 after 6 years compared to 23% in the conventional cohort (p = 0.026). There was no difference when using the CWP1990 definition (27% vs 31%, p = 0.546). When adjusted for important baseline data, the odds ratio for having CWP2019 was 2.57 (95% CI 1.02–6.50), in the conventional group compared to the tight control group (p = 0.046). A high level of fear-avoidance behaviour towards physical activity was associated with CWP2019, OR 10.66 (95% CI 1.01–112.14), but not with CWP1990 in the tight control cohort. Conclusion A more stringent definition of CWP identifies patients with a more serious pain condition, which potentially could be prevented by an initial tight control management. Besides tight control, caregivers should pay attention to fear-avoidance behaviour and tailor treatment. Key Points • CWP2019 is a more stringent definition of chronic widespread pain and identifies patients with a more serious pain condition. • Patients with a serious pain condition could be helped by frequent follow-ups. • This study suggests that a special attention of fear-avoidance behaviour towards physical activity in patients with RA is needed.