Trends in prescribed opioid therapy for non-cancer pain for individuals with prior substance use disorders.

Long-term opioid therapy for non-cancer pain has increased. Caution is advised in prescribing for persons with substance use disorders, but little is known about actual health plan practices. This paper reports trends and characteristics of long-term opioid use in persons with non-cancer pain and a substance abuse history. Using health plan data (1997-2005), the study compared age-sex-standardized rates of incident, incident long-term and prevalent long-term prescription opioid use, and medication use profiles in those with and without substance use disorder histories. The CONsortium to Study Opioid Risks and Trends study included adult enrollees of two health plans, Kaiser Permanente of Northern California (KPNC) and Group Health Cooperative (GH) of Seattle, Washington. At KPNC (1999-2005), prevalence of long-term use increased from 11.6% to 17.0% for those with substance use disorder histories and from 2.6% to 3.9% for those without substance use disorder histories. Respective GH rates (1997-2005), increased from 7.6% to 18.6% and from 2.7% to 4.2%. Among persons with an opioid disorder, KPNC rates increased from 44.1% to 51.1%, and GH rates increased from 15.7% to 52.4%. Long-term opioid users with a prior substance abuse diagnosis received higher dosage levels, were more likely to use Schedule II and long-acting opioids, and were more often frequent users of sedative-hypnotic medications in addition to their opioid use. Since these patients are viewed as higher risk, the increased use of long-term opioid therapy suggests the importance of improved understanding of the benefits and risks of opioid therapy among persons with a history of substance abuse, and the need for more careful screening for substance abuse history than is the usual practice.