Short-term outcomes of patients being treated for chronic intractable pain at a liaison clinic and exacerbating factors of prolonged pain after treatment.

BACKGROUND: Although a multidisciplinary approach is often recommended to treat intractable pain, this approach does not completely prevent uncontrolled pain in some patients. The aim of this retrospective study was to investigate the exacerbating factors of prolonged, intractable pain among patients being treated at a pain liaison clinic.

METHODS: The participants of this study were 94 outpatients (32 men, 62 women) with chronic intractable pain who visited our hospital between April 2013 and February 2015. Demographic and clinical information was obtained from all patients at baseline. Experts in various fields, including anesthesia, orthopedic surgery, psychiatry, physical therapy, and nursing, were involved in the treatment procedures. All patients were assessed before and after a 6-month treatment period using the following measures: the Numeric Rating Scale (NRS); the Pain Catastrophizing Scale (PCS); the Hospital Anxiety and Depression Scale (HADS); the Pain Disability Assessment Scale (PDAS); and the Oswestry Disability Index (ODI). All participants were then divided into two groups based on their self-reported pain after treatment: a pain relief group (n = 70) and a prolonged pain group (n = 24). The exacerbating factors of prolonged pain after treatment in the pain liaison outpatient clinic were analyzed using univariate and multiple logistic regression analysis.

RESULTS: A significant improvement in NRS scores was observed after the 6-month follow-up period. After treatment, 24 (25.5%) of the 94 patients reported having prolonged pain. Significant improvements were seen in the PCS, PDAS, and ODI scores in the pain relief group, and in the HADS depression scores in the prolonged pain group. On univariate and multiple regression analysis, HADS depression scores were identified as a factor related to prolonged pain after treatment.

CONCLUSIONS: The results of the present study suggest that severe depression at the initial visit to the liaison outpatient clinic was an exacerbating factor for prolonged pain after treatment.