Association between substance use disorder status and pain-related function following 12 months of treatment in primary care patients with musculoskeletal pain.

UNLABELLED: The goal of this study was to examine relationships between substance use disorder (SUD) history and 12-month outcomes among primary care patients with chronic noncancer pain (CNCP). Patients were enrolled in a randomized trial of collaborative care intervention (CCI) versus treatment as usual (TAU) to improve pain-related physical and emotional function. At baseline, 72 of 362 patients (20.0%) had a history of SUD. Compared to CNCP patients without SUD, those with comorbid SUD had poorer pain-related function and were more likely to meet criteria for current major depression and posttraumatic stress disorder (all P values <.05). Logistic regression analyses were conducted to examine whether SUD status was associated with clinically significant change over 12 months in pain-related function (30% reduction in Roland Morris Disability Questionnaire Score). The overall model was not significant in the CCI group. However, within the TAU group, participants with a SUD history were significantly less likely to show improvements in pain-related function (OR = .30, 95% CI = .11-.82). CNCP patients with comorbid SUD reported greater functional impairment at baseline. Patients with SUD who received usual care were 70% less likely to have clinically significant improvements in pain-related function 12 months postbaseline, and SUD status did not impede improvement for the CCI group.

PERSPECTIVE: Chronic noncancer pain patients with a history of a substance use disorder (SUD) report poorer pain-related functioning and are less likely to experience clinically significant improvements from usual pain treatment. Providers should assess for SUD status and provide more intensive interventions for these patients.