RESUMO
OBJECTIVE: The psychological health of patients with chronic low back pain (CLBP) influences their response to a number of conservative and invasive pain treatments. However, evidence is still scarce regarding the impact of anxiety and depression in the clinical outcomes of multidisciplinary pain management over time. This study, based on longitudinal data from a clinical practice setting, aimed to assess the effectiveness of the usual multidisciplinary approach provided to CLBP patients and to explore the impact of anxiety and depression symptoms and their interaction on clinical outcomes. METHODS: In this study, participants included were adult patients in their first consultation in a multidisciplinary chronic pain clinic. Anxiety and depression symptoms were assessed with the Hospital Anxiety and Depression Scale (HADS). The Brief Pain Inventory (BPI) and the Shortened Treatment Outcomes in Pain Survey (S-TOPS) were used to assess outcomes. Linear mixed effects models were used to assess the impact of anxiety, depression, and their interaction on treatment outcomes. RESULTS: A total of 284 patients (age 60.4 ± 13.7 years, 74.6% female) with CLBP were included at baseline. The majority of patients had both anxiety and depression and experienced higher pain severity (P < 0.001) and higher pain-related disability (P < 0.001). Anxiety and depression mainly predicted changes in pain interference over time. Their interaction significantly predicted changes in pain interference. CONCLUSIONS: Anxiety, depression, and their interaction are associated with changes in pain disability at one-year follow-up. These findings encourage the pretreatment screening of anxiety and depression as independent symptoms in patients with CLBP in order to design more tailored and effective multidisciplinary treatments.