Factors Associated with Disability and Sick Leave in Early Complex Regional Pain Syndrome Type-1.

Objective: Factors influencing disability and work absence in complex regional pain syndrome type-1 (CRPS)-1 have not been thoroughly described in the literature. We sought to determine whether demographic variables, work-related factors, CRPS clinical severity ratings, pain scores, or psychological variables were associated with disability and sick leave in early CRPS-1. Methods: A total of 66 CRPS-1 patients were recruited within 12 weeks of CRPS onset. Patients completed measures of pain, depression, anxiety, stress, pain catastrophizing, and pain-related fear. A physical examination was conducted to assess signs and symptoms of CRPS and to calculate a CRPS severity score. Demographic details, clinical details, treatments, work type, and work status were recorded. Results: In multivariate analyses, the following factors were associated with greater disability: higher pain scores, more restricted ankle or wrist extension, and higher levels of depression. Among the 49 who were either working or studying before developing CRPS, 28 had stopped work or study at the time of assessment. Multivariate analyses showed that sick leave was more likely among those whose CRPS was triggered by more severe injuries, whose work was more physically demanding, among those with higher disability scores, and there was also a significant effect of depression on sick leave, which was mediated by disability. Discussion: Although the study was cross-sectional and so cannot differentiate cause from effect, results suggest that even in the early stages of CRPS, a cycle of pain, disability, depression, and work absence can emerge. Treatments aimed to prevent this cycle may help prevent adverse long-term outcomes.