Background Chronic opioid therapy for chronic non-cancer pain (CNCP) is increasingly common in community practice. Concomitant with this practice change, rates of fatal opioid overdose have increased. It is not known to what extent overdose risks are elevated among patients receiving medically prescribed chronic opioid therapy. Objective To estimate rates of opioid overdose and their association with average prescribed daily opioid dose among patients receiving medically prescribed chronic opioid therapy. Design Cox proportional hazards models were used to estimate overdose risk as a function of average daily opioid dose (morphine equivalents) received at time of overdose. Setting Health maintenance organization. Patients Individuals (n=9940) who received 3+ opioid prescriptions within 90-days for CNCP between 1997 and 2005. Measurements Average daily opioid dose over the previous 90 days from automated pharmacy data. Primary outcomes, non-fatal and fatal overdoses, were identified through diagnostic codes from inpatient and outpatient care and death certificates and confirmed by medical record review. Results Fifty-one opioid-related overdoses were identified, including six deaths. Compared to patients receiving 1-20mg of opioids per day (0.2% annual overdose rate), patients receiving 50-99 mg had a 3.7 fold increase in overdose risk (95% C.I. 1.5, 9.5) and a 0.7% annual overdose rate. Patients receiving 100mg or more per day had an 8.9 fold increase in overdose risk (95% C.I. 4.0, 19.7) and a 1.8% annual overdose rate. Limitations Increased overdose risk among patients on higher dose regimens may be due to confounding by patient differences and by use of opioids in ways not intended by prescribing physicians. The small number of overdoses in the study cohort is also a limitation. Conclusions Patients receiving higher doses of prescribed opioids are at increased risk of opioid overdose, underscoring the need for close supervision of these patients.

Objectives This paper describes characteristics of opioid use episodes for non-cancer pain and defines thresholds for the transition into Defacto Long-term Opioid Therapy. Methods CONSORT (CONsortium to Study Opioid Risks and Trends) includes adult members of two health plans serving over one-percent of the U.S. population. Opioid use episodes beginning in 1997–2005 were classified as Acute, Episodic, Long-term/Lower Dose, or Long-term/Higher Dose. Results Defacto Long-term Opioid Therapy was defined by opioid use episodes lasting longer than 90 days with at least 10 prescriptions and/or at least 120 days supply dispensed. Long-term/Higher Dose episodes (<1.5% of all episodes) were characterized by daily or near daily use, a mean duration of about 1000 days, and an average daily dose of about 55 milligrams. They accounted for more than half the total morphine equivalents dispensed from 1997–2006. Short-acting, less potent opioids (e.g. hydrocodone with acetaminophen) were by far the most commonly prescribed medications for acute, episodic and long-term episodes. Long-acting (sustained-release) opioids were the predominately prescribed medication in a minority of long-term episodes (6–12%). Discussion Defacto Long-term Opioid Therapy was characterized by considerable diversity in medications, dosage, and frequency of use. Long-term opioid therapy may evolve from acute or episodic use in the absence of an agreed upon treatment plan. Defined thresholds for Defacto Long-term Opioid Therapy provide a possible check point for physicians and health plans to ensure that patients receiving opioid medications long-term are managed according to a treatment plan that is documented and monitored.

Objective To report trends and characteristics of long-term opioid use for non-cancer pain. Methods CONSORT (CONsortium to Study Opioid Risks and Trends) includes adult enrollees of two health plans serving over one-percent of the US population. Using automated data, we constructed episodes of opioid use between 1997 and 2005. We estimated age-sex standardized rates of opioid use episodes beginning in each year (incident) and on-going in each year (prevalent), and the percent change in rates annualized (PCA) over the 9 year period. Long-term episodes were defined as > 90 days with 120+ days supply or 10+ opioid prescriptions in a given year. Results Over the study period, incident long-term use increased from 8.5 to 12.1 per 1,000 at Group Health (GH) (6.0% PCA), and 6.3 to 8.6 per 1,000 at Kaiser Permanente of Northern California (KPNC) (5.5% PCA). Prevalent long-term use doubled from 23.9 to 46.8 per 1,000 at GH (8.5% PCA), and 21.5 to 39.2 per 1,000 at KPNC (8.1% PCA). Non-Schedule II opioids were the most commonly used opioid among patients engaged in long-term opioid therapy, particularly at KPNC. Long-term use of Schedule II opioids also increased substantially at both health plans. Among prevalent long-term users in 2005, 28.6% at GH and 30.2% at KPNC were also regular users of sedative hypnotics. Conclusion Long-term opioid therapy for non-cancer pain is increasingly prevalent, but the benefits and risks associated with such therapy are inadequately understood. Concurrent use of opioids and sedative-hypnotics was unexpectedly common and deserves further study.

Objectives We describe age and gender trends in long-term use of prescribed opioids for chronic noncancer pain in 2 large health plans. Methods Age- and gender-standardized incident (beginning in each year) and prevalent (ongoing) opioid use episodes were estimated with automated health care data from 1997 to 2005. Profiles of opioid use in 2005 by age and gender were also compared. Results From 1997 to 2005, age–gender groups exhibited a total percentage increase ranging from 16% to 87% for incident long-term opioid use and from 61% to 135% for prevalent long-term opioid use. Women had higher opioid use than did men. Older women had the highest prevalence of long-term opioid use (8%–9% in 2005). Concurrent use of sedative-hypnotic drugs and opioids was common, particularly among women. Conclusions Risks and benefits of long-term opioid use are poorly understood, particularly among older adults. Increased surveillance of the safety of long-term opioid use is needed in community practice settings.

Objective-We report trends in long-term opioid use among patients from two large health plans with a history of depression.Methods-Using claims data, age and gender-adjusted rates for long-term (>90 days) opioid use episodes were calculated for 1997-2005, comparing those with and without a depression diagnosis in the prior two years. Opioid use characteristics were calculated for those with a long-term episode in 2005.Results-Incident and prevalent long-term opioid use rates were three times higher in those with a history of depression. Prevalent long-term use per 1,000 in patients with a history of depression increased from 69.8 to 125.9 at Group Health, and from 84.3 to 117.5 at Kaiser Permanente of Northern California between 1997 and 2005. Those with a history of depression were more likely to receive a higher average daily dose, greater days supply, and Schedule II opioids than non-depressed persons.Conclusion-Persons with a history of depression are more likely to receive long-term opioid therapy for non-cancer pain than those without a history of depression. Results suggest that longterm opioid therapy for non-cancer pain is being prescribed to a different population in clinical practice than the clinical trial populations where opioid efficacy has been established.