Psychiatric Disorders Among Patients Seeking Treatment for Co-Occurring Chronic Pain and Opioid Use Disorder.

OBJECTIVE: Psychiatric comorbidities complicate treatment of patients with chronic pain and opioid use disorder, but the prevalence of specific comorbid psychiatric disorders in this population has not been systematically investigated.

METHODS: 170 consecutive participants entering a treatment research program for co-occurring chronic pain and opioid use disorder between March 2009 and July 2013 were evaluated with the Structured Clinical Interview for DSM-IV-TR Axis I Disorders (SCID-I/P) and the Diagnostic Interview for DSM-IV Personality Disorders (DIPD-IV).

RESULTS: The prevalence of any lifetime (and current) comorbid Axis I disorder was 91% (75%); 52% met criteria for lifetime anxiety disorder (48% current), 57% for lifetime mood disorder (48% current), and 78% for lifetime nonopioid substance use disorder (34% current). Common current anxiety diagnoses were posttraumatic stress disorder (21%), generalized anxiety disorder (16%), and panic disorder without agoraphobia (16%). Common current mood diagnoses were major depressive disorder (40%) and dysthymia (11%). A majority of patients had a personality disorder (52%).

CONCLUSIONS: High rates and persistence of co-occurring psychiatric disorders, including anxiety or mood disorders, may explain in part the difficulty providers have treating patients with co-occurring opioid use disorder and chronic pain and suggest possible targets for improving treatment.

TRIAL REGISTRATION: ClinicalTrials.gov identifiers: buprenorphine/naloxone treatment (NCT00634803), opioid treatment program-based methadone maintenance treatment (NCT00727675).