Impact of pre–treatment pain intensity and disability on multidisciplinary pain treatment outcomes: a cross–sectional study

Background: Although multidisciplinary pain treatment is effective for chronic pain, there may be treatment challenges when severe pain significantly impairs daily life activities. Purpose: To determine whether the degree of daily life impairment caused by pain influences treatment outcomes. Methods: The study comprised 123 patients treated between July 2019 and June 2024. The cutoff scores for pain intensity (assessed using the numerical rating scale) and daily life disability (assessed using the Pain Disability Assessment Scale) were ≥ 5 and ≥ 40, respectively. Patients with chronic pain who exceeded these thresholds at their initial visit were categorized as the severe group (n = 15), whereas those who scored below these thresholds were classified as the non–severe group (n = 108). Psychosocial factors related to pain (measured by the Pain Catastrophizing Scale [PCS], Hospital Anxiety and Depression Scale [HADS], Pain Self–Efficacy Questionnaire, and Athens Insomnia Scale [AIS]) and quality of life (measured by the EuroQol Five Dimensions Questionnaire [EQ–5D]) were used as outcomes. Group comparisons were conducted at baseline and longitudinally over 6 months. Results: At baseline, all measures except the PCS score (rumination) differed significantly between groups. Over the subsequent 6 months, the non–severe group exhibited significant improvements across all outcomes. In contrast, the severe group demonstrated significant improvements in only the HADS (anxiety), EQ–5D, and AIS scores. Conclusion: Patients with severe pain at baseline exhibited limited treatment effects despite multidisciplinary treatment. These findings suggest that higher pain intensity and greater impairment in daily life are predictive of poorer treatment effectiveness.