"In our study, there was greater evidence for an association between substance use and chronic pain among inpatients than among MMTP [Methadone Maintenance Treatment Program] patients. Among inpatients, there were significant bivariate relationships between chronic pain and pain as a reason for first using drugs, multiple drug use, and drug craving. In the multivariate analysis, only drug craving remained significantly associated with chronic pain. Not surprisingly, inpatients with pain were significantly more likely than those without pain to attribute the use of alcohol and other illicit drugs, such as cocaine and marijuana, to a need for pain control. These results suggest that chronic pain contributes to illicit drug use behavior among persons who were recently using alcohol and/or cocaine. Inpatients with chronic pain visited physicians and received legitimate pain medications no more frequently than those without pain, raising the possibility that undertreatment or inability to access appropriate medical care may be a factor in the decision to use illicit drugs for pain."
Rosenblum, Andrew, PhD, Herman Joseph, PhD, Chunki Fong, MS, Steven Kipnis, MD, Charles Cleland, PhD, Russell K. Portenoy, MD, "Prevalence and Characteristics of Chronic Pain Among Chemically Dependent Patients in Methadone Maintenance and Residential Treatment Facilities," Journal of the American Medical Association (Chicago, IL: American Medical Association, May 14, 2003), Vol. 289, No. 18, pp. 2376-2377.