Long-Term Safety and Efficacy of Subcutaneous Methylnaltrexone in Patients with Opioid-Induced Constipation and Chronic Noncancer Pain: A Phase 3, Open-Label Trial.

OBJECTIVE: Methylnaltrexone, a peripherally acting µ-opioid receptor antagonist, alleviates opioid-induced constipation. Understanding its long-term safety and efficacy profile in patients with chronic noncancer pain is warranted given the persistence of opioid-induced constipation. METHODS.: In this phase 3, multicenter, open-label trial, adults with chronic noncancer pain (N = 1034) received subcutaneous methylnaltrexone 12 mg once daily for 48 weeks. RESULTS: The most common adverse events were gastrointestinal related (e.g., abdominal pain, diarrhea, nausea) and were mild to moderate in intensity. Only 15.2% of patients discontinued because of an adverse event. Serious cardiac-related adverse events occurred in nine patients. Of the seven instances of major adverse coronary events reported, three were adjudicated after external review; all instances occurred in patients with cardiovascular risk factors. Methylnaltrexone elicited a bowel movement within four hours in 34.1% of the injections throughout the 48-week treatment period. CONCLUSIONS: Change from baseline in mean weekly bowel movement rate, Bowel Movement Straining Scale score, Bristol Stool Scale score, and mean percentage of patients with complete evacuation from baseline to week 48 were significantly improved ( P < 0.001 for all). Long-term subcutaneous methylnaltrexone was well tolerated, with no new safety concerns, and provided consistent opioid-induced constipation relief in patients with chronic noncancer pain.

Injury and Liability Associated with Implantable Devices for Chronic Pain.

BACKGROUND: Due to an increase in implantable device-related anesthesia pain medicine claims, the authors investigated anesthesia liability associated with these devices. METHODS: After institutional review board approval, the authors identified 148 pain medicine device claims from 1990 or later in the Anesthesia Closed Claims Project Database. Device-related damaging events included medication administration events, infections, hematomas, retained catheter fragments, cerebrospinal fluid leaks, cord or cauda equina trauma, device placed at wrong level, stimulator incorrectly programmed, delay in recognition of granuloma formation, and other issues. RESULTS: The most common devices were implantable drug delivery systems (IDDS; 64%) and spinal cord stimulators (29%). Device-related care consisted of surgical device procedures (n = 107) and IDDS maintenance (n = 41). Severity of injury was greater in IDDS maintenance claims (56% death or severe permanent injury) than in surgical device procedures (26%, P < 0.001). Death and brain damage in IDDS maintenance claims resulted from medication administration errors (n = 13; 32%); spinal cord injury resulted from delayed recognition of granuloma formation (n = 9; 22%). The most common damaging events for surgical device procedures were infections, inadequate pain relief, cord trauma, retained catheter fragments, and subcutaneous hygroma. Care was more commonly assessed as less than appropriate (78%) and payments more common (63%) in IDDS maintenance than in surgical device procedure claims (P < 0.001). CONCLUSIONS: Half of IDDS maintenance claims were associated with death or permanent severe injury, most commonly from medication errors or failure to recognize progressive neurologic deterioration. Practitioners implanting or managing devices for chronic pain should exercise caution in these areas to minimize patient harm.

Trends in Pain Medicine Liability.

BACKGROUND: The authors examined changes in the frequency of pain medicine malpractice claims and associated treatment modalities and outcomes over time. METHODS: The authors analyzed trends in pain medicine claims from 1980 to 2012 in the Anesthesia Closed Claims Project database by binary logistic regression on year of event. Pain procedures in claims from 2000 to 2012 were compared with the proportion of pain procedures reported to the National Anesthesia Clinical Outcomes Registry in 2010-2014. RESULTS: Malpractice claims for pain medicine increased from 3% of 2,966 total malpractice claims in the Anesthesia Closed Claims Project database in 1980-1989 to 18% of 2,743 anesthesia claims in 2000-2012 (odds ratio [OR], 1.088 per year; 95% CI, 1.078 to 1.098; P < 0.001). Outcomes in pain claims became more severe over time, with increases in death and permanent disabling injury (OR, 1.094 per year; P < 0.001). Nonneurolytic cervical injections increased to 27% of pain claims in 2000-2012 (OR, 1.054; P < 0.001), whereas National Anesthesia Clinical Outcomes Registry demonstrates that lumbar injections are a more common procedure. Claims associated with medication management increased to 17% of pain claims in 2000-2012 (OR, 1.116 per year; P < 0.001). CONCLUSIONS: Pain medicine claims have increased over time and have increased in severity. Claims related to cervical procedures were out of proportion to the frequency with which they are performed. These liability findings suggest that pain specialists should aggressively continue the search for safer and more effective therapies.

Psychiatric Comorbidity Is Associated Prospectively with Diminished Opioid Analgesia and Increased Opioid Misuse in Patients with Chronic Low Back Pain.

BACKGROUND: Opioids are frequently prescribed for chronic low back pain (CLBP), but there are little prospective data on which patient subgroups may benefit. Psychiatric comorbidity, such as high levels of depression and anxiety symptoms (termed comorbid negative affect [NA]), is a common presentation and may predict diminished opioid analgesia and/or increased opioid misuse. METHODS: The authors conducted a 6½-month prospective cohort study of oral opioid therapy, with an active drug/placebo run-in period, in 81 CLBP patients with low, moderate, and high levels of NA. Treatment included an opioid titration phase with a prescribing physician blinded to NA group assignment and a 4-month continuation phase, during which subjects recorded daily pain levels using an electronic diary. The primary outcome was the percent improvement in average daily pain, summarized weekly. RESULTS: There was an overall 25% dropout rate. Despite the high NA group being prescribed a higher average daily dose of morphine equivalents, linear mixed model analysis revealed that the 24 study completers in each of the high NA and low NA groups had an average 21 versus 39% improvement in pain, respectively (P < 0.01). The high NA group also had a significantly greater rate of opioid misuse (39 vs. 8%, P < 0.05) and significantly more and intense opioid side effects (P < 0.01). CONCLUSIONS: These results indicate that the benefit and risk considerations in CLBP patients with high NA versus low NA are distinctly different. Thus, NA is an important phenotypic variable to characterize at baseline, before deciding whether to prescribe opioids for CLBP.

Systematic literature review and meta-analysis of the efficacy and safety of prescription opioids, including abuse-deterrent formulations, in non-cancer pain management.

OBJECTIVE: This study was conducted to compare safety and efficacy outcomes between opioids formulated with technologies designed to deter or resist tampering (i.e., abuse-deterrent formulations [ADFs]) and non-ADFs for commonly prescribed opioids for treatment of non-cancer pain in adults. METHODS: PubMed and Cochrane Library databases were searched for opioid publications between September 1, 2001 and August 31, 2011, and pivotal clinical trials from all years; abstracts from key pain conferences (2010-2011) were also reviewed. One hundred and ninety-one publications were initially identified, 68 of which met eligibility criteria and were systematically reviewed; a subset of 16 involved a placebo group (13 non-ADFs vs placebo, 3 ADFs vs placebo) and reported both efficacy and safety outcomes, and were included for a meta-analysis. Summary estimates of standardized difference in mean change of pain intensity (DMCPI), standardized difference in sum of pain intensity difference (DSPID), and odds ratios (ORs) of each adverse event (AE) were computed through random-effects estimates for ADFs (and non-ADFs) vs placebo. Indirect treatment comparisons were conducted to compare ADFs and non-ADFs. RESULTS: Summary estimates for standardized DMCPI and for standardized DSPID indicated that ADFs and non-ADFs showed significantly greater efficacy than placebo in reducing pain intensity. Indirect analyses assessing the efficacy outcomes between ADFs and non-ADFs indicated that they were not significantly different (standardized DMCPI [0.39 {95% confidence interval (CI) 0.00-0.76}]; standardized DSPID [-0.22 {95% CI -0.74 to 0.30}]). ADFs and non-ADFs both were associated with higher odds of AEs than placebo. Odds ratios from indirect analyses comparing AEs for ADFs vs non-ADFs were not significant (nausea, 0.87 [0.24-3.12]; vomiting, 1.54 [0.40-5.97]; dizziness/vertigo, 0.61 [0.21-1.76]; headache, 1.42 [0.57-3.53]; somnolence/drowsiness, 0.47 [0.09-2.58]; constipation, 0.64 [0.28-1.49]; pruritus 0.41 [0.05-3.51]). CONCLUSION: ADFs and non-ADFs had comparable efficacy and safety profiles, while both were more efficacious than placebo in reducing pain intensity.

Relationship of negative affect and outcome of an opioid therapy trial among low back pain patients.

OBJECTIVES: Patients with chronic noncancer pain frequently report symptoms of depression and anxiety (negative affect), which are associated with higher ratings of pain intensity and a greater likelihood of being prescribed chronic opioid therapy. The purpose of this secondary analysis was to test the hypothesis that initial levels of negative affect can predict treatment-related outcomes in a double-blind, placebo-controlled study of extended-release (ER) hydromorphone among opioid-tolerant patients with chronic low back pain. METHODS: Four hundred fifty-nine (N = 459) patients participated in the titration/conversion phase of a multicenter study, of which 268 were randomized to receive once-daily hydromorphone or placebo. All patients completed the Hospital Anxiety and Depression Scale (HADS) at baseline and were divided evenly into Low (N = 157), Moderate (N = 155), and High (N = 147) negative affect groups based on their scores. Group differences in numerical pain intensity measures at home and in the clinic, Roland-Morris Disability ratings, and measures of symptoms from the Subjective Opiate Withdrawal Scale (SOWS) throughout the trial were analyzed. RESULTS: Two hundred sixty-eight of the initial 459 subjects who entered the 2 to 4-week titration/conversion phase (pretreatment) were successfully randomized to either placebo or ER hydromorphone; a total of 110 patients then completed this double-blind phase of the study. Those in the Moderate and High negative affect groups tended to drop out more often during the titration/conversion phase because of the adverse effects or lack of efficacy of their prescribed opioid than those in the Low negative mood group (P < 0.05). Overall, those patients in the Moderate and High groups reported significantly higher pain intensity scores in at-home and in-clinic pain intensity ratings (P < 0.05), greater disability on the Roland-Morris Scale (P < 0.01), and more withdrawal symptoms on the SOWS (P < 0.05) than those in the Low group. Higher negative affect scores also predicted less favorable ratings of the study drug during the titration phase (P < 0.05). Interestingly, the High negative affect group showed the most improvement in pain in the placebo condition (P < 0.05). CONCLUSIONS: Negative affect is associated with diminished benefit during a trial of opioid therapy and is predictive of dropout in a controlled clinical trial.

Injury and liability associated with cervical procedures for chronic pain.

BACKGROUND: Prompted by an increase in interventional pain treatments performed at the level of the cervical spine, we investigated the characteristics and patterns of injury in malpractice claims collected from January 1, 2005 to December 31, 2008. METHODS: We compared claims arising from cervical pain treatments with all other chronic pain claims collected from the American Society of Anesthesiologists' closed claims database between 2005 and 2008. Claims for spinal cord injury underwent in-depth analysis for mechanisms of injury and use of sedation during the procedure. RESULTS: Claims related to cervical interventions represented 22% (64/294) of chronic pain treatment claims. Patients who underwent cervical procedures were healthier (American Society of Anesthesiologists' score, 1-2; P < 0.001) and were more often women (P = 0.011). Of the patients who underwent a cervical procedure, 59% experienced spinal cord damage compared with 11% of patients with other chronic pain (P < 0.001), with direct needle trauma as the predominant cause (31%). General anesthesia or sedation was used in 67% of cervical procedure claims associated with spinal cord injuries but in only 19% of cervical procedure claims not associated with spinal cord injuries (P < 0.001). Of the patients who underwent cervical procedures and had spinal cord injuries, 25% were nonresponsive during the procedure compared with 5% of the patients who underwent cervical procedures and did not have spinal cord injuries (P < 0.05, κ = 0.52). CONCLUSIONS: Injuries related to cervical interventional pain treatment were often severe and related to direct needle trauma to the spinal cord. Traumatic spinal cord injury was more common in patients who received sedation or general anesthesia and in those who were unresponsive during the procedure. Further studies are crucial to define the usefulness of cervical interventions and to improve their safety.

Efficacy of subcutaneous methylnaltrexone in the treatment of opioid-induced constipation: a responder post hoc analysis.

OBJECTIVE: Methylnaltrexone, a selective peripherally acting mu-opioid receptor antagonist, effectively treats opioid-induced constipation (OIC) in patients with advanced illness and shows efficacy in patients with chronic nonmalignant pain. The objective was to identify patients who achieved maximal treatment effect based on response to initial four methylnaltrexone doses. DESIGN: A post hoc analysis of a randomized, double-blind, placebo-controlled study evaluating patients with OIC and chronic nonmalignant pain who received 12 mg subcutaneous methylnaltrexone daily for 4 weeks was performed to determine if response to the first four methylnaltrexone doses predicted overall response during the study. Patients receiving ≥8 doses were included. OUTCOME MEASURES: Patients having ≥3 rescue-free bowel movements (RFBMs)/week; change from baseline in RFBMs/week; percentage of doses with RFBMs within 4 hours after dosing. RESULTS: Of 137 patients, 58 patients (42.3%) had RFBMs after ≥2 of four doses. Among those with response to ≥2 of four doses, 81% had ≥3 RFBMs/week vs. 43% for those with response to <2 of four (P < 0.0001). Those with RFBMs after ≥2 of first four doses averaged 4.8 RFBMs/week vs. 2.0 RFBMs/week for those with <2 of four (P < 0.0001). Percentage of subsequent injections resulting in RFBMs within 4 hours was 45.9 ± 27.6 for those with response to ≥2 of four doses vs. 17.1 ± 19.1 for those with response to <2 of four (P < 0.0001). Abdominal pain was the most frequently reported adverse event. CONCLUSION: Early response to ≥2 of first four doses of methylnaltrexone identified patients who demonstrated a particularly robust effect of treatment over the duration of use.

Malpractice claims associated with medication management for chronic pain.

BACKGROUND: Medication management is an integral part of chronic pain management. Prompted by an increase in the role of medication management in anesthesia chronic pain liability, we investigated the characteristics of malpractice claims collected from 2005 to 2008. METHODS: After Institutional Review Board approval, we compared medication management claims with other chronic pain claims from the American Society of Anesthesiologists Closed Claims Database of 8,954 claims. Claims for death underwent in-depth analysis. RESULTS: Medication management represented 17% of 295 chronic non-cancer pain claims. Compared with other chronic pain claims, medication management patients tended to be younger men (P < 0.01) with back pain. Most patients were prescribed opioids (94%) and also additional psychoactive medications (58%). Eighty percent of patients had at least one factor commonly associated with medication misuse and 24% had >or= 3 factors. Most claims (82%) involved patients who did not cooperate in their care (69%) or inappropriate medication management by physicians (59%). Death was the most common outcome in medication management claims (57% vs. 9% in other chronic pain claims, P < 0.01). Factors associated with death included long-acting opioids, additional psychoactive medications, and >or= 3 factors commonly associated with medication misuse. Alleged addiction from prescribed opioids was the complaint in 24%. Appropriateness of care and payments was similar for medication management versus other chronic pain claims. CONCLUSIONS: Most anesthesia malpractice claims for medication management problems involved patients with a history of risk behaviors commonly associated with medication misuse. Malpractice claims arising from medication management had a high proportion of deaths with both patient and physician contributions to the outcome.

Removal of opioid/acetaminophen combination prescription pain medications: assessing the evidence for hepatotoxicity and consequences of removal of these medications.

Opioid/acetaminophen combination products are widely prescribed for the management of moderate to moderately severe pain. Acetaminophen, when improperly used, can lead to liver damage and even acute liver failure. In June 2009, an FDA advisory committee recommended elimination of prescription acetaminophen combination products because of the risk of hepatotoxicity associated with use of these medications. The FDA advisory committee reviewed numerous observational studies and adverse event reporting data. The aims of this article are to: 1) provide a summary and epidemiologic critique of the studies and evidence the FDA advisory committee reviewed; 2) examine the potential consequences, such as poorly managed pain or a shift to treatment with other medications with greater potential toxicity and/or restricted availability, if the FDA follows the advisory committee vote; and 3) outline alternate strategies the FDA should consider for reducing hepatotoxicity associated with opioid/acetaminophen combination products.

Risk of hepatotoxicity-related hospitalizations among patients treated with opioid/acetaminophen combination prescription pain medications.

OBJECTIVE: This study determined the risk of serious hepatotoxicity resulting in hospitalizations among patients prescribed opioid/acetaminophen combinations. METHODS: A retrospective cohort study using an insurance claims database was conducted. Adult patients with ≥1 claim for oxycodone/acetaminophen or hydrocodone/acetaminophen combinations were included (N = 1,228,356). A pre-post design was employed to compare serious hepatotoxicity risk before versus after initiation of opioid/acetaminophen combination. Serious hepatotoxicity risk between the opioid/acetaminophen group and a control group of opioid-alone users (N = 11,809) was also examined. Within the opioid/acetaminophen group, risk of hepatotoxicity-related hospitalizations pre- versus post-opioid/acetaminophen treatment was compared using the normal approximation with the binomial distribution. The incidence rate of hepatotoxicity-related hospitalizations for the opioid/acetaminophen group was compared with the opioid-alone group using multivariate Poisson regression adjusting for baseline differences between groups. RESULTS: Of the opioid/acetaminophen cohort, hepatotoxicity-related hospitalization risk in the 6-month post-opioid/acetaminophen period was lower than that in the pre-period with a risk reduction of 1.2 per 10,000 (pre-period = 0.12%; 95% confidence interval [CI], 0.12 to 0.13; post-period = 0.11%; 95% CI, 0.11 to 0.12). In the 12-month period, risk increased in the post-period by 2.4 per 10,000 (pre-period = 0.14%; 95% CI, 0.14 to 0.15; post-period = 0.17%; 95% CI, 0.16 to 0.18). After adjusting for confounders, the opioid-alone group did not demonstrate a lower rate of hepatotoxicity-related hospitalizations than the opioid/acetaminophen group (incidence rate ratio of opioid-alone over opioid/acetaminophen = 2.9; 95% CI, 1.8 to 4.7). CONCLUSIONS: There is no population data-based evidence supporting elevated risk of hepatotoxicity-related hospitalization associated with opioid/acetaminophen combinations.

Efficacy of dronabinol as an adjuvant treatment for chronic pain patients on opioid therapy.

UNLABELLED: We assessed the efficacy of dronabinol (Marinol capsules; Solvay Pharmaceuticals, Brussels, Belgium), a synthetic Delta(9)-THC (tetrahydrocannabinol), in 30 patients taking opioids for chronic pain to determine its potential analgesic effects as an adjuvant treatment. Phase I of this 2-phase study was a randomized, single-dose, double-blinded, placebo-controlled, crossover trial in which subjects were randomly administered either 10 mg or 20 mg of dronabinol or identical placebo capsules over the course of three, 8-hour visits. Baseline self-report measures, hourly ratings of pain intensity, pain relief, pain bothersomeness, treatment satisfaction, mood, side effects, and blood serum levels were obtained. Phase II was an extended open-label titrated trial of dronabinol as add-on medication to patients on stable doses of opioids. Results of the Phase I study showed that patients who received dronabinol experienced decreased pain intensity and increased satisfaction compared with placebo. No differences in benefit were found between the 20 mg and 10 mg doses. In the Phase II trial, titrated dronabinol contributed to significant relief of pain, reduced pain bothersomeness, and increased satisfaction compared with baseline. The incidence of side effects was dose-related. Overall, the use of dronabinol was found to result in additional analgesia among patients taking opioids for chronic noncancer pain. PERSPECTIVE: This study examines the effect of adding a cannabinoid to the regimen of patients with chronic pain who report significant pain despite taking stable doses of opioids. The results of our preliminary study suggest that dronabinol, a synthetic THC, may have an additive effect on pain relief.

Interpreting urine drug tests: prevalence of morphine metabolism to hydromorphone in chronic pain patients treated with morphine.

OBJECTIVE: Pain medicine practitioners frequently use urine drug testing (UDT) to monitor adherence to opioid therapy. It can be difficult to interpret a result as normal or abnormal in relation to which opioid compounds are expected to be found in the urine. We investigated whether hydromorphone may be a metabolite of morphine normally appearing in UDT of patients prescribed morphine. DESIGN: This is a retrospective case-control study of urine toxicology results in pain patients taking only morphine. Inclusion criteria included urine results positive for morphine only (controls) or morphine and hydromorphone (cases). Demographic and medical history variables, and any history of aberrant drug behavior were recorded and related to the presence or absence of hydromorphone in the urine. RESULTS: Hydromorphone was present in 21 of 32 cases (66%), none of whom had a history of aberrant drug behavior. Positive cases occurred more frequently in women, in those taking higher daily doses of morphine, and in those with higher urine morphine concentrations (P < 0.05). Only morphine urine concentration was a significant predictor of the hydromorphone metabolite in a logistic regression model (P < 0.05). CONCLUSIONS: Hydromorphone is likely a minor metabolite of morphine, normally appearing in the UDT of patients taking morphine. This finding assists in determining whether a UDT result is normal or abnormal, and subsequently whether a patient is compliant with opioid therapy. This observation should be confirmed by a prospective study in a controlled environment. Variables such as gender, morphine dose, morphine urine concentration, and genetic determinants of morphine metabolism should be investigated further.

Urine toxicology screening among chronic pain patients on opioid therapy: frequency and predictability of abnormal findings.

OBJECTIVE: To examine the incidence of abnormal urine toxicology screening among chronic pain patients prescribed opioids for their pain and to relate these results to patient descriptors and type, number, and dose of prescribed opioids. METHODS: A retrospective analysis of data from 470 patients who had urine screening at a pain management program in an urban teaching hospital was performed. Urine samples were analyzed using gas chromatography-mass spectrometry. Patients were categorized as having urine screens that were "normal" (expected findings based on their prescribed drugs) or abnormal. Abnormal findings were those of (1) absence of a prescribed opioid, (2) presence of an additional nonprescribed controlled substance, (3) detection of an illicit substance, and (4) an adulterated urine sample. RESULTS: Forty-five percent of the patients were found to have abnormal urine screens. Twenty percent were categorized as having an illicit substance in their urine. Illicit substances and additional drugs were found more frequently in younger patients than in older patients (P<0.001). No other variables were found to predict abnormal urine screen results. DISCUSSION: These results confirm past findings that random urine toxicology screens among patients prescribed opioids for pain reveal a high incidence of abnormal findings. Common patient descriptors, and number, type, and dose of prescribed opioids were found to be poor predictors of abnormal results.

Pain intensity and interference with functioning and well-being in subgroups of patients with chronic pain treated with once-daily hydrocodone tablets.

BACKGROUND: A previous 52-week trial of patients with chronic noncancer, non-neuropathic pain (CNNP) showed clinically meaningful improvement in pain intensity, pain interference, and physical health-related quality of life (HRQL) following daily treatment with an extended-release, once-daily hydrocodone (Hysingla(®) ER; HYD) bitartrate tablet. OBJECTIVE: To examine treatment response within patient subgroups and to assess between-subgroup differences in effectiveness and side effect profile. METHODS: Data were from an open-label 52-week trial of treatment with HYD tablets (20-120 mg, once-daily) for patients with moderate-to-severe CNNP. Binary subgroups were defined for the following six factors: age, gender, opioid experience, baseline pain severity, history of depression, and stable HYD dose at completion of a 45-day dose-titration period. Univariable and multivariable models examined changes in average pain intensity (API; 11-point numeric rating scale), pain interference (Brief Pain Inventory-Interference subscale [BPI-I]), physical and mental HRQL (36-item Short Form health survey Physical and Mental Component Summaries [PCS and MCS]), and sleep quality (Medical Outcomes Study Sleep Scale Sleep Problems Index [SPI]) from baseline to maintenance, and subgroup differences in adverse events. RESULTS: All subgroups showed clinically meaningful improvements in API, BPII, and PCS scores; no subgroups showed improvements in MCS or SPI. Between subgroup comparisons found greater improvements for opioid-naïve patients and for patients with severe baseline pain. Incidence of adverse events differed minimally between subgroups. CONCLUSION: Regardless of subgroup, patients with CNNP treated with HYD showed clinically meaningful improvements in pain intensity, pain interference, and physical HRQL, although not in mental HRQL or sleep quality. Improvements were generally larger for opioid-naïve patients and patients with severe baseline pain.

Efficacy and safety of once-daily, extended-release hydrocodone in individuals previously receiving hydrocodone/acetaminophen combination therapy for chronic pain.

BACKGROUND: Hydrocodone/acetaminophen combination analgesics are frequently prescribed for chronic pain management; however, acetaminophen presents potential hepatotoxicity to patients and thus dose limitations. These opioid medications are also widely abused. Once-daily, single-entity hydrocodone (Hysingla™ ER tablets [HYD]) is a novel formulation with abuse-deterrent properties for the management of chronic pain and represents a suitable option for those patients receiving analgesics containing the same opioid analgesic, hydrocodone. This post-hoc analysis evaluated the efficacy and safety of HYD in patients whose primary pre-study analgesic was hydrocodone/acetaminophen analgesics (23-31% of the study populations). METHODS: Data were analyzed from two Phase III trials, a 12-week randomized, placebo-controlled trial (RCT) and an open-label, 52-week trial. In both trials, a dose-titration period with HYD was followed by respective periods of fixed-dose double-blind (randomized controlled trial [RCT]) or open-label, flexible-dose maintenance treatment. Pain intensity was assessed using a numerical rating scale (0-10, 0 = no pain). For the RCT, primary and sensitivity analyses of pain scores used different approaches to handle missing data. Safety data for both studies were summarized. RESULTS: In the RCT, the mean baseline pain score was 7.3. Pain relief was greater with HYD than placebo during double-blind treatment. In the open-label, flexible-dose trial, the majority of patients were maintained on their titrated dose. Mean baseline pain score was 6.3, about 57% of patients completed the 1-year maintenance period, and mean pain scores were between 3.6 and 4.1 during the maintenance period. Use of supplemental pain medication decreased or was maintained during the maintenance treatment with HYD. Adverse events in both trials were typical of those associated with opioid analgesics. CONCLUSION: In patients whose primary pretrial analgesic was hydrocodone/acetaminophen combination tablets, single-entity HYD was effective in reducing pain intensity and in maintaining analgesia over time without need for continued dose increase. HYD's safety and tolerability profiles were similar to other opioid analgesics.

National Perioperative Outcomes for Intrathecal Pump, Spinal Cord Stimulator, and Peripheral Nerve Stimulator Procedures.

BACKGROUND: There is abundant literature on the long-term complications of intrathecal pumps (ITP), spinal cord stimulators (SCS), and peripheral nerve stimulators (PNS) used in the treatment of chronic pain. There is less information, however, on the perioperative complications of these procedures. OBJECTIVE: Exploration of the perioperative outcomes of implantable pain devices. STUDY DESIGN: Observational study. SETTING: University hospitals, community hospitals, specialty hospitals, attached surgery centers, and freestanding surgery centers METHODS: Data were obtained from the National Anesthesia Clinical Outcomes Registry (NACOR) of the Anesthesia Quality Institute (AQI). Information was collected on patient demographics, procedure information, anesthetic administered, diagnosis linked to the procedure, and perioperative outcomes. RESULTS: The search yielded 12,611 ITP, 19,276 SCS, and 15,184 PNS cases from 2010 to 2014. In this sample, the majority of procedures were performed at community hospitals, not university medical centers. The most common diagnosis cited for an ITP was an implant complication (n = 2,570), followed by spasticity, and non-malignant back pain. For SCS, the most common diagnoses were lower back pain (n = 5,515) or radiculopathy (n = 2,398). For PNS, by far the most common diagnosis related to urinary dysfunction (n = 8,745), with painful bladder syndrome a small minority (n = 133). General anesthetics were more often performed for ITP than for SCS and PNS procedures (60.6% vs. 31.8% and 32.2%, respectively). Hemodynamic instability was a common outcome (13.9% for ITP procedures); other common outcomes for all the procedures included case delays, inadequate pain control, and extended PACU stays. LIMITATIONS: Despite the large sample size in this study, not all medical centers transmit their outcome data to NACOR. Furthermore, some institutions do not report clinical outcomes for every case to NACOR, making the sample size of assessing complications smaller and potentially more biased. Finally, procedures identified in the NACOR database using CPT may be similar but not identical and therefore potentially influence outcomes. CONCLUSIONS: Databases such as NACOR can provide rich information on ITP, SCS, and PNS for physicians performing these procedures. In this sample, ITP procedures, performed on the patients with the most severe cormobidities and often-requiring general anesthesia, were the most likely to be associated with hemodynamic instability, inadequate pain control, and extended PACU stays. Complications relating to the ITP are also the most common reason for an operation. These findings underscore the importance of proper patient selection for ITP and other implantable pain devices, in particular for patients with malignant pain or multiple co-morbidities. To identify the root causes of complications, additional information is needed on the procedure performed (e.g., an implant vs a revision), the surgical technique used, and the device implanted, as well as on specific patient comorbidities. Such information will likely become more available as resources like NACOR expand and as electronic medical record systems and coding become more integrated.

Predicting aberrant drug behavior in patients treated for chronic pain: importance of abuse history.

Physicians can encounter problems in prescribing opioids for some patients with chronic pain such as multiple unsanctioned dose escalations, episodes of lost or stolen prescriptions, and positive urine drug screenings for illicit substances. This study explored the usefulness of questions on abuse history in predicting problems with prescribing opioids for patients at a hospital-based pain management program. One hundred forty-five (145) patients who were taking long- and short-acting opioids for their pain were classified as high or low risk on the basis of their responses to interview questions about 1) substance abuse history in their family, 2) past problems with drug or alcohol abuse, and 3) history of legal problems. The treating physicians completed a questionnaire about problems that they had encountered with their patients. Problem behaviors were verified through chart review. No differences in demographic characteristics were found between those classified as high and low risk. Patients who admitted to a family history of substance abuse, a history of legal problems, and drug or alcohol abuse were prone to more aberrant drug-related behaviors, including a higher incidence of lost or stolen prescriptions and the presence of illicit substances in their urine (P < 0.05). Patients classified as high risk also had a significantly higher frequency of reported mental health problems and motor vehicle accidents. More of these patients smoked cigarettes, tended to need a cigarette within the first hour of the day, took higher doses of opioids, and reported fewer adverse effects from the medications than did those without such a history (P < 0.05). This study demonstrates that questions about abuse history and legal problems can be useful in predicting aberrant drug-related behavior with opioid use in persons with chronic noncancer pain.

Medical resource use and costs among pain patients with potential opioid-tolerability issues.

OBJECTIVE: To estimate excess medical resource use and costs associated with prescription opioid (RxO) tolerability issues. DESIGN: This was an observational, retrospective analysis of deidentified administrative claims data. SETTING: The study included commercially insured patients treated in different healthcare settings captured in the Truven MarketScan claims database. PATIENTS: Patients aged 18-64 years initiating treatment with an RxO (index) and continuously treated with pain relievers over a 6-month period were selected. "Switchers" were patients who discontinued their index RxO and switched to non-RxO pain relievers < 30 days post-index, and whose last pain reliever in the 6-month follow-up period was not an RxO. Such switching was considered a proxy for RxO-tolerability issues. "Continuous RxO users" were patients who remained on the index RxO for the follow-up period. Switchers and continuous RxO users were matched 1:1 on propensity score, baseline medical costs, index RxO days supply, and short-/long-acting index RxO. MAIN OUTCOME MEASURES: Six-month follow-up medical resource use and costs were compared between matched switchers and continuous RxO users. RESULTS: A total of 10,704 pairs of switchers and continuous RxO users were matched. In the 6-month follow-up period, switchers had more outpatient (7.5 vs 6.8; p < 0.001) and inpatient (0.05 vs 0.04; p = 0.002) visits and longer inpatient stays (0.26 days vs 0.19; p = 0.006) compared to continuous RxO users. Switchers also had higher total medical costs ($4,522 vs $3,657; p < 0.001). CONCLUSIONS: Switchers incur greater medical resource use and costs than similar patients continuously treated with their index RxO.