Abstracts The Journal of Pain S81

(420) Observations of hydrocodone co-prescriptions and non-reported prescription medications in a population ofthose with chronic pain

R West, M Rosenthal, A Pesce, E Gonzales, C Mikel, C West, S Latyshev,and P Almazan; Millennium Research Institute, San Diego, CA

While efficacious for the treatment of chronic pain, the use of opioid analgesicsis associated with a high overdose risk, concomitant use of non-prescribeddrugs, and diversion. Among patients with chronic pain prescribed hydroco-done, the prevalence of illicit drug use and prescription drug misuse is ashigh as 24%. Another issue with the use of opioid analgesics is the danger ofadverse drug events due to drug-drug interactions. The purpose of this studywas to understand the relationship of hydrocodonewith concomitant prescrip-tions and non-prescribed medications in order to identify and minimize healthrisks. The retrospective data analyses were based on the LC-MS/MS testing re-sults of 290,627 de-identified urine specimens tested between November2009 and September 2010 at Millennium Laboratories. The database wassorted for reported hydrocodone prescriptions (38.8% of specimens,n=112,873) and non-reported hydrocodone (6.1% of specimens, n=17,861, de-tected by LC-MS/MSwithout a prescription listed).Within these two groups thecorresponding prevalence of reported prescription medications, detection ofprescribed medications, and the incidence of non-reported medication usewere determined. These two analyses were then compared to the incidenceof reported and detected medications for the entire cohort of 290,627 speci-mens. The most commonly reported prescription medications for all threegroups were opioids, benzodiazepines and carisoprodol. The benzodiazepineclass of drugs was observed to have the greatest incidence of non-reported usein all groups examined. The results suggest that adherence to hydrocodone isnot an indicator of adherence to other medications. The results demonstratethat the cohort of patients taking non-prescribed hydrocodone were morelikely to take other non-prescribed medications than the group taking hydro-codone with a prescription. This information may help physicians make clinicaldecisions about monitoring adherence, identifying non-prescription drug use,minimizingdrug-drug interactions and adverse drug events, and initiating con-versations with patients about safety and concurrent conditions.

(421) Chronic opioid therapy urine drug screening: effects ofhealth care system implementation of an opioid prescrib-ing guideline

J Turner, M Von Korff, K Saunders, L LeResche, S Shortreed, and S Thielke;Group Health Research Institute, Seattle, WA

Although urine drug screening (UDS) for patients on chronic opioid therapy(COT) is widely recommended, there is a paucity of data on its use and waysto optimize use in primary care settings. In October 2010, Group Health (GH),a health care system in Washington State, implemented a COT guideline,with the aimof reducing opioid abuse,misuse, diversion, and overdose. GH cat-egorized COT patients, based on opioid dose and risk factors, into threegroups, with UDS recommendations for each. To examine the guideline’s im-pact on UDS, we identified non-cancer COT patients during: (1) the guidelineimplementation year (10/2010 – 9/2011), (2) the guideline planning year (10/2009 – 9/2010), and (3) the prior (baseline) year (10/2008 – 9/2009). We definedCOT as, in $6 months in the year, filling prescriptions for $70 days’ supply ofopioids in the prior 3 months. We examined the GH opioid dose categoriesand UDS recommendations: (1) low dose (<20 mg daily morphine-equivalentdose [MED]): consideration for UDS once a year, (2) moderate dose (20-119mg MED): UDS at least once a year, and (3) high dose ($120 mg MED): UDSat least twice a year. The proportion of all COT patients who received at leastone UDS in the year increased from 7% and 13% in the baseline and planningyears, respectively, to 50% after guideline implementation. Among patientswith moderate opioid dose, rates of at least one UDS per year were 8%,15%, and 56%, in the baseline, planning, and implementation years, respec-tively. An increase was also seen after guideline implementation in the propor-tion of high-dose COT patients who received two or more UDS (baseline, 4%;planning year, 7%; implementation year, 22%). The results indicate a dramaticincrease in UDS rates associated with opioid guideline implementation bya health care system. Supported by NIH/NIA grant R01AG034181.

(422) Abuse liability of oral formulations of hydromorphone inopioid-experienced, recreational drug users: importanceof onset of effect

L Webster, M Smith, andM Iverson; Lifetree Clinical Research, Salt Lake City, UT

Rate of onset is an important determinant of the abuse liability of opioid for-mulations. OROS hydromorphone ER is a once-daily opioid formulation that re-leases hydromorphone at a controlled rate. The objective of this study was tocompare the abuse-related effects of various formulations of hydromorphone,with particular emphasis on early time intervals after drug administration. Thiswas a double-blind, placebo-controlled, randomized study in subjects (N=28)with a history of recreational opioid use. In phase A, subjects received immedi-ate-release (IR) hydromorphone 8 mg, intact OROS hydromorphone ER 16 and32 mg, a milled preparation of OROS hydromorphone ER 8 mg, and placebo ina crossover design. In phase B, subjects who tolerated all treatments in Phase Areceived single doses of IR hydromorphone (8 mg) and OROS hydromorphoneER (64mg). Time tomaximumeffect (TEmax) and area under the effect curve at2 hours (AUE0-2) were assessed for subject-rated outcomes of ‘‘high’’, ‘‘drug lik-ing’’, and ‘‘euphoria’’. All formulations produced effects significantly differentthan placebo (P<0.05). For all subject-rated outcomes, the TEmax for all intactdoses of OROS hydromorphone ER (range: 7.8-13.3 hours) was greater than theTEmax for 8 mg IR hydromorphone (range: 2.4-3.5 hours) (P<0.05). For AUE0-2,all intact doses of OROS hydromorphone ER produced significantly lower levelsof ‘‘high’’ and ‘‘euphoria’’ compared with 8 mg hydromorphone IR (P<0.05).The effects of milled OROS hydromorphone ER were similar to those of IR hy-dromorphone. The slower onset of effect and decreased reports of ‘‘high’’ and‘‘euphoria’’ suggest that OROS hydromorphone ERmay have less abuse liabilitythan IR hydromorphone when intact tablets are taken whole. Technical edito-rial andwriting assistance provided by SynchronyMedical, LLC, funded byMal-linckrodt Inc., a Covidien company, Hazelwood, MO.

(423) Opioid initiation in persons with a new episode ofchronic non-cancer pain

M Sullivan, B Martin, M Edlund, J Russo, and A DeVries; University ofWashington, Seattle, WA

We investigated acute and chronic opioid initiation rates in adults with non-cancer chronic pain using administrative claims data from HealthCore (HC)and the Arkansas (AR) Medicaid from 1/1/01-12/31/06. Individuals were >24years of age, no cancer, were diagnosed with a new episode of back/neckpain, headache, or arthritis pain, no opioids for 6 months, and 24 months con-tinuous enrollment. Baseline clinical characteristics assessed in 6 month pre-in-dex CNCP period. Any opioid use was defined as one or more prescriptions inthe 18 month post-index period. Chronic opioid use was defined as receiving>90 days of opioid use within a 6-month period with no gap in use of >30days. There were 541,825 subjects for HC and 13,730 for AR. Any opioid usewas higher in AR (52.9%) compared to HC (34.7%). A majority of subjectswho used opioids used them in a non-chronic fashion; HC (95.4%), AR(89.3%). Being older than 65 (HC OR=0.43; AR OR=0.44), surgery (HCOR=2.49; AR OR=3.54), opioid use disorder (HC OR=1.82; AR OR=2.14) weremost prognostic for any opioid use. Back pain (HC OR=1.93; AR OR=2.26) andopioid use disorder (HC OR=4.27; AR OR=3.01) were most prognostic forchronic opioid use compared to any opioid use. Among subjects with new ep-isodes of chronic pain, one-half to one-third are prescribed opioids and 5 to10% of those will use opioids chronically. Back pain patients are most likelyto transition to chronic opioid use compared to other chronic pain types. It isworrisome that persons with prior substance use disorders were more likelyto be prescribed opioids and more likely to transition to chronic opioid use.