Prevalence and Characteristics of Chronic Pain Among Chemically Dependent Patients in Methadone Maintenance and Residential Treatment Facilities

CONTEXT: Little is known about the prevalence and characteristics of chronic pain among patients with different types of chemical dependency. OBJECTIVES: To estimate the prevalence and to examine the characteristics of chronic severe pain in chemically dependent populations receiving methadone maintenance or inpatient residential treatment. DESIGN, SETTING, AND PARTICIPANTS: Representative samples of 390 patients from 2 methadone maintenance treatment programs (MMTPs) and 531 patients from 13 short-term residential substance abuse treatment (inpatient) programs, all in New York State, were surveyed in late 2000 and early 2001. MAIN OUTCOME MEASURE: Prevalence of chronic severe pain, defined as pain that persisted for more than 6 months and was of moderate to severe intensity or that significantly interfered with daily activities. RESULTS: Chronic severe pain was experienced by 37% of MMTP patients (95% confidence interval CI, 32%-41%) and 24% of inpatients (95% CI, 20%-28%; P =.03). Pain of any type or duration during the past week was reported by 80% of MMTP patients and 78% of inpatients. Among those with chronic severe pain, 65% of MMTP patients and 48% of inpatients reported high levels of pain-related interference in physical and psychosocial functioning. Among MMTP patients, correlates of chronic pain in a multivariate model were age (odds ratio OR, 2.08; 95% CI, 1.17-3.70), chronic illness (OR, 1.88; 95% CI, 1.07-3.29), lifetime psychiatric illness (OR, 1.77; 95% CI, 1.06-2.97), psychiatric distress (OR, 1.63; 95% CI, 1.22-2.18), and time in treatment (OR, 2.23; 95% CI, 1.06-4.68). Among inpatients, the correlates of chronic pain were race (blacks vs whites: OR, 0.52; 95% CI, 0.31-0.90; Hispanics vs whites: OR, 0.48; 95% CI, 0.24-0.95), drug craving (OR, 2.78; 95% CI, 1.54-5.02), chronic illness (OR, 2.17; 95% CI, 1.37-3.43), and psychiatric distress (OR, 1.36; 95% CI, 1.03-1.81). Among those with chronic severe pain, inpatients were significantly more likely than MMTP patients to have used illicit drugs, as well as alcohol, to treat their pain complaint (51% vs 34%, P =.005) but were less likely to have been prescribed pain medications (52% vs 67%, P =.01). CONCLUSIONS: Chronic severe pain is prevalent among patients in substance abuse treatment, especially MMTP patients. Pain is associated with functional impairment and correlates of pain vary with the population. Self-medication for pain with psychoactive drugs appears especially problematic among substance users who enroll in drug-free treatment programs. Substance abuse treatment programs need to develop comprehensive and structured pain management programs.