REVIEW OF: Ilgen MA et al, JAMA Psychiatry 2020; published online July 29, 2020

Co-occurring substance use disorders (SUD) and chronic pain can be tough to treat. Little research has focused directly on this phenomenon, since most studies of pain exclude individuals with SUD. However, a few small, open studies of psychotherapeutic pain management in the presence of SUD have been promising.

In the current (2020) study, researchers tested a new psychosocial technique designed specifically for patients with co-occurring SUD and chronic pain. Improving Pain During Addiction Treatment (ImPAT) is a behavioral intervention that combines two techniques: cognitive behavioral therapy (CBT) and acceptance-based therapy. A pilot study in 2019 showed promise in using this technique for treating pain with opioid use disorder, and a large, randomized study of veterans with pain and SUD (Ilgen MA et al, Addiction 2016;111(8):1385–1393) found the intervention to be associated with decreased pain, increased functioning, and decreased alcohol use. However, the 2016 study’s generalizability was limited in that it only included veterans and predominantly men. The current study was an attempt to extend those findings to the larger community, analyzed separately for men and women.

Patients were recruited from an abstinence-based, 60-day residential treatment program: Community Programs, Inc. in Waterford, Michigan. Medications for addiction treatment (MAT) were not offered in the program and were not included in the study design. Participants had severe SUD, involving primarily cannabis, opioids and alcohol for men, and opioids and cocaine for women, and all participants reported moderate to severe pain in the 3 months prior to the study. 510 individuals (48% women) were randomized to ImPAT or to a supportive psychoeducational control (SPC). Both interventions were manualized, and were provided by trained masters-level therapists, in 8 one-hour group sessions over 4 weeks. ImPAT highlighted the link between pain, functioning, and substance use and worked to explore new ways of conceptualizing and responding to pain while preventing return to substance use. SPC focused on topics like nutrition and the course of addiction, which were relevant to the patients but distinct from ImPAT. Follow-up assessments were done at 3, 6, and 12 months. Primary outcomes were pain intensity, pain-related functioning, and pain tolerance. Secondary outcome was frequency of alcohol and drug use. The study was funded by grants from NIDA and NIAAA.

The group sessions had good attendance, with 91.7% of participants completing the 12-month programs. Of the six outcome measures (three each for men and women), only two favored the efficacy of the intervention. Men showed increased pain tolerance throughout the follow-up period, and women showed decreased pain intensity at 12 months. However, there was no decrease in alcohol and drug use compared to the control group. The effect sizes for all outcomes were small: 0.4 for pain tolerance in men at 3 months, but otherwise not over 0.23 for any outcome.

A strength of the study was its control group, which was equivalent to the active treatment in format, intensity, and duration. A major limitation was the lack of MAT in either arm, which is a cornerstone of addiction treatment.

CATR’S TAKE
CBT and acceptance-based therapy alone, without medications, may not be effective for managing chronic pain and addiction together. It may be more effective if used in conjunction with MAT—future studies ought to address this.