Purpose: The purpose of this study was to examine the cost-effectiveness of pain treatments in two pain centers in Japan.
Methods: The study population comprised 91 patients receiving various treatments for chronic pain, which were divided into three categories: (1) medication, (2) medication + nerve block, and (3) other modalities (exercise and/or pain education). Pain was assessed using the Pain Disability Assessment Scale (PDAS) score, Hospital Anxiety and Depression Scale (HADS) score, Pain Catastrophizing Scale (PCS) score, and EQ-5D score. First, the reliability of the EQ-5D score first assessed by evaluating the correlation this score with those of the other pain-related evaluation instruments, and then the cost effectiveness of the pain treatments was evaluated. Evaluation of medical costs was based on data provided from the Management Services of the hospital, which in turn were based on national health scheme medical treatment fees. The quality-adjusted life year (QALY) value was calculated from the EQ-5D score, converted to 12 months, and then used for cost-benefit analysis along with medical treatment fees.
Results: According to the recent IASP classification, more patients had chronic neuropathic pain (41) than chronic primary pain (37 patients) or chronic musculoskeletal pain (27 patients). There was a significant correlation between the EQ-5D score and the PDAS, HADS, and PCS scores, which demonstrated the reliability of the EQ-5D score. Significant improvement in the HADS, PCS, and EQ-5D scores was noted after 3 months of pain treatment. Calculation of the cost-effectiveness based on the estimated annual medical treatment cost and QALY revealed a mean value of US $45,879 ± 103,155 per QALY (median US $16,903), indicating adequate socioeconomic utility.
Conclusion: Based on our results, the EQ-5D is reliable for evaluating chronic pain in patients. The medico-economic balance was appropriate for all treatments provided in two comprehensive pain centers in Japan.
Keywords: Chronic pain; Cost effectiveness; IASP classification of chronic pain; Quality-adjusted life year; Severity classification.