Safety Of Opioids Research Articles

Breakthrough cancer pain: twenty-five years of study.

Breakthrough cancer pain (BTcP) is an episode of severe pain that "breaks through" a period of persistent pain at least partly controlled by a stable opioid regimen. Although mentioned in the literature decades ago, it has been only 25 years since the first effort to define and measure it. Controversy about the definition of BTcP continues despite an international effort to achieve consensus. Nevertheless, common approaches to measurement of BTcP have led to a robust literature, including many surveys that have described prevalence, characteristics, and association with adverse outcomes. Measurement also has been important for clinical trials of new drug formulations specifically designed for BTcP. Several approaches have been reported in the literature, although most of them have never been substantiated with appropriate studies. Administration of an opioid as needed is the most common treatment. Twenty-five years of research has produced a more refined understanding of the safety and efficacy of oral opioids in this context, and provided the clinical trials data necessary to attain regulatory approval of multiple new formulations specifically developed for BTcP. Transmucosal formulations of fentanyl may provide meaningful analgesia within 5 to 15 minutes. Given the difference in cost, transmucosal formulations should be considered in a subset of patients with BTcP, including those with pain that are not adequately controlled with an oral drug and those with distress associated with the rapid pain onset. The long-term use of opioids for BTcP remains to be clarified. Future studies should assess the potential of personalized treatment of BTcP.

Pharmacotherapy of Pain in the Older Population: The Place of Opioids.

Pain is a common symptom in older people. It is possible that pain is underreported in older persons due to an incorrect belief that it is an inevitable part of aging. Opioid analgesics are potent medications, with confirmed efficacy for the treatment of moderate to severe pain. These drugs are commonly used in older persons. However, there is insufficient evidence regarding safety of opioids in older patients. One of the reasons for this is the lack of randomized, controlled clinical trials. People of advanced age often have comorbidites and use other prescription drugs, as well as over-the-counter (OTC) compounds, thus making them more suceptible to the risk of interactions with opioids. Significant pharmacokinetic and pharmacodynamic changes that occur with advancing age increase the risk of adverse effects of opioids. There are also some discrepancies between guidelines, which recommend the use of lower doses of opioids in older patients, and the findings in the literature which suggest that pain is often undertreated in this age group. It seems that there are significant variations in the tolerability of different opioid analgesics in older people. Morphine, fentanyl, oxycodone, and buprenorphine are still the preferred evidence-based choices for add-on opioid therapy for these patients. However, the safety and efficacy of other opioids in older patients, especially if comorbidities and polypharmacy are present, is still questionable. This review addresses the most important aspects of the use of opioids in older persons, focusing on pharmacokinetics, pharmacodynamics, adverse effects, and interactions.

Morphine Suppository versus Indomethacin Suppository in the Management of Renal Colic: Randomized Clinical Trial.

Background. Renal colic is a medical emergency due to the rapid onset and devastating nature of its pain. Opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) are both used as first-line choices in its management. Aim. This study aimed to compare the efficacy and safety of opioids and NSAIDs in the management of acute renal colic. Methods. One hundred and fifty-eight patients were divided into two groups (n = 79) and received either 10 mg morphine or 100 mg indomethacin suppositories. The severity of pain was measured using verbal numeric rating scale at baseline and 20, 40, 60, and 90 minutes after the administration of analgesics. Drug side effects as well as patients' vital signs were also recorded. Results. The mean decrease in the pain score during the first 20 minutes was significantly higher among those who received morphine suppository. However, no significant difference was observed between the two groups regarding the mean decrease in pain score during the first 40, 60, and 90 minutes after the admission. Prevalence of drug side effects or changes in the vital signs was not significantly different between the two groups. Conclusions. Morphine suppositories seem to be more efficient in achieving rapid pain relief comparing to indomethacin.

Interchangeability, Safety and Efficacy of Modified-Release Drug Formulations in the USA: The Case of Opioid and Other Nervous System Drugs.

Modified-release drugs may provide clinical advantages compared to immediate-release forms and improve convenience to the patient and health outcomes. Concerns have been raised regarding interchangeability, efficacy, and safety of modified-release formulations. This study analyses all US Food and Drug Administration (FDA)-approved modified-release formulations and market trends, and illustrates how bioequivalence and safety of generic modified-release products compare to their respective brand name drugs and other generic drugs with different formulation design characteristics. This study also examines major concerns related to modified-release formulations: safety of opioids and bioequivalence of generic bupropion and methylphenidate. Study data were derived from the FDA electronic versions of the FDA's Orange Book (OB) and the FDA safety communications web page. Medicare Part D utilization and expenditures data were extracted from the Centers for Medicare and Medicaid. In May 2015, 276 (11.9%) of the 2325 active ingredients and fixed-dose combinations listed in the FDA's Orange Book had at least one modified-release form approved by the FDA. The number of approvals increased over time; 52.5% of modified releases were approved in the period 2000-May 2015. The FDA required a risk evaluation and mitigation strategy (REMS) to ensure that the benefits of extended-release opioids outweighed its risks of overdose and abuse. The REMS involved 16 new drug applications and 25 abbreviated new drug applications. The FDA addressed interchangeability problems with generic modified-release alternatives of bupropion and methylphenidate including lack of bioequivalence, reduced efficacy, and increased incidence of adverse events. Systematic post-marketing surveillance studies are needed to assess differences in safety, interchangeability, and efficacy of drugs with modified- and immediate-release formulations.

Buprenorphine - an attractive opioid with underutilized potential in treatment of chronic pain.

Despite proven clinical utility, buprenorphine has not been used widely for the treatment of chronic pain. Questions about “ceiling effect” or bell-shaped curve observed for analgesia in preclinical studies and potential withdrawal issues on combining with marketed μ-agonists continue to hinder progress in expanding full potential of buprenorphine in the treatment of cancer and noncancer pain. Mounting evidence from clinical studies and conclusions drawn by a panel of experts strongly support superior safety and efficacy profile of buprenorphine vs marketed opioids. No ceiling on analgesic effect has been reported in clinical studies. The receptor pharmacology and pharmacokinetics profile of buprenorphine is complex but unique and contributes to its distinct safety and efficacy. The buprenorphine pharmacology also allows it to be combined with other μ-receptor opioids for additivity in efficacy. Transdermal delivery products of buprenorphine have been preferred choices for the management of pain but new delivery options are under investigation for the treatment of both opioid dependence and chronic pain.

The Changing Use of Intravenous Opioids in an Emergency Department.

IntroductionGovernment agencies are increasingly emphasizing opioid safety in hospitals. In 2012, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) started a sentinel event program, the “Safe Use of Opioids in Hospitals.” We sought to determine if opioid use patterns in our emergency department (ED) changed from 2011, before the program began, to 2013, after start of the program.MethodsThis was a retrospective study of all adult ED patients who received an intravenous opioid and had a serum creatinine measured. We recorded opioids used, dose prescribed, and serum creatinine. As an index of the safety of opioids, uses of naloxone after administration of an opioid was recorded.ResultsMorphine is still the most commonly used opioid by doses given, but its percentage of opioids used decreased from 68.9% in 2011 to 52.8% in 2013. During the same period, use of hydromorphone increased from 27.5% to 42.9%, while the use of fentanyl changed little (3.6% to 4.3%). Naloxone administration was rare after an opioid had been given. Opioids were not dosed in an equipotent manner.ConclusionThe use of hydromorphone in our ED increased by 56% (absolute increase of 15.4%), while the use of morphine decreased by 30.5% (absolute decrease 16.1%) of total opioid use from 2011 to 2013. The JCAHO program likely was at least indirectly responsible for this change in relative dosing of the opioids. Based on frequency of naloxone administered after administration of an opioid, the use of opioids was safe.

Effects of opioids on breathlessness and exercise capacity in chronic obstructive pulmonary disease. A systematic review.

Patients with chronic obstructive pulmonary disease (COPD) commonly suffer from breathlessness, deconditioning, and reduced health-related quality of life (HRQL) despite best medical management. Opioids may relieve breathlessness at rest and on exertion in COPD. We aimed to estimate the efficacy and safety of opioids on refractory breathlessness, exercise capacity, and HRQL in COPD. This was a systematic review and metaanalysis using Cochrane methodology. We searched Cochrane Central Register of Controlled Trials, MEDLINE, and Embase up to 8 September, 2014 for randomized, double-blind, placebo-controlled trials of any opioid for breathlessness, exercise capacity, or HRQL that included at least one participant with COPD. Effects were analyzed as standardized mean differences (SMDs) with 95% confidence intervals (CIs) using random effect models. A total of 16 studies (15 crossover trials and 1 parallel-group study, 271 participants, 95% with severe COPD) were included. There were no serious adverse effects. Breathlessness was reduced by opioids overall: SMD, -0.35 (95% CI, -0.53 to -0.17; I(2), 48.9%), by systemic opioids (eight studies, 118 participants): SMD, -0.34 (95% CI, -0.58 to -0.10; I(2), 0%), and less consistently by nebulized opioids (four studies, 82 participants): SMD, -0.39 (95% CI, -0.71 to -0.07; I(2), 78.9%). The quality of evidence was moderate for systemic opioids and low for nebulized opioids on breathlessness. Opioids did not affect exercise capacity (13 studies, 149 participants): SMD, 0.06 (95% CI, -0.15 to 0.28; I(2), 70.7%). HRQL could not be analyzed. Findings were robust in sensitivity analyses. Risk of study bias was low or unclear. Opioids improved breathlessness but not exercise capacity in severe COPD.

Opioids for agitation in dementia.

Agitation is a common experience for people living with dementia, particularly as day-to-day function and cognition start to decline more. At the present time there are limited pharmacological options for relieving agitation and little is known about the safety and efficacy of opioid drugs in this setting. To determine the clinical efficacy and safety of opioids for agitation in people with dementia. We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialized Register, on 13 June 2014 using the terms: narcotic OR opioid OR opium OR morphine OR buprenorphine OR codeine OR dextromoramide OR diphenoxylate OR dipipanone OR dextropropoxyphene OR propoxyphene OR diamorphine OR dihydrocodeine OR alfentanil OR fentanyl OR remifentanil OR meptazinol OR methadone OR nalbuphine OR oxycodone OR papaveretum OR pentazocine OR meperidine OR pethidine OR phenazocine OR hydrocodone OR hydromorphone OR levorphanol OR oxymorphone OR butorphanol OR dezocine OR sufentanil OR ketobemidone.ALOIS contains records of clinical trials identified from monthly searches of a number of major healthcare databases such as MEDLINE, EMBASE and PscyINFO, as well as numerous trial registries and grey literature sources. Randomised, controlled trials of opioids compared to placebo for agitation in people with dementia. Two authors independently assessed the studies identified by the search against the inclusion criteria. There are currently no completed randomised, placebo controlled trials of opioids for agitation in dementia. There are two potentially relevant trials still in progress. We found insufficient evidence to establish the clinical efficacy and safety of opioids for agitation in people with dementia. There remains a lack of data to determine if or when opioids either relieve or exacerbate agitation. More evidence is needed to guide the effective, appropriate and safe use of opioids in dementia.

Pharmacogenomics and Opioid Analgesics: Clinical Implications.

Variation exists in patient response on analgesic treatment in terms of efficacy and safety. This variation may be in part explained by pharmacogenomics. This paper aimed to review data on pharmacogenomics of opioid analgesics focusing on the effect of genetic variation on the efficacy and safety of these agents. Current evidence suggests that pharmacogenomics contribute to variation in efficacy and safety of opioids. However, most data come from case control studies and case reports. In addition, a recognized drawback in the field of pharmacogenomics is the common occurrence of false positive association between polymorphisms and the investigated outcome. Prospective studies are needed to further elucidate the clinical implications of available data as well as to define the guidelines for the clinical application of pharmacogenomic data. Furthermore, basic research should focus on the identification of biologically meaningful polymorphisms enabling a hypothesis with biological plausibility driven research in the field of pharmacogenomics of analgesics. Moreover, the publication of relevant negative results should be favoured.

P-glycoprotein in the developing human brain: a review of the effects of ontogeny on the safety of opioids in neonates.

The human blood brain barrier is responsible for maintaining brain homeostasis and protecting against potentially toxic substances. The ATP-binding cassette drug efflux protein, P-glycoprotein (P-gp) is a key player in actively extruding a wide range of xenobiotics such as opioids from the brain. Because the blood brain barrier is structurally and functionally immature in neonates, opioids may have a greater penetration to the central nervous system. This may influence the efficacy and safety of opioids in the newborn. Understanding the extent of P-gp's expression in the brain in the embryo, fetus, and newborn will facilitate rational opioid use during pregnancy and the neonatal period. This review aims to summarize the current evidence that associates the ontogeny of P-gp and the susceptibility to opioid-induced adverse respiratory effects in neonates. To date, evidence suggests that the expression of P-gp in the human brain is low at birth, contributing to increased susceptibility.

Opioids for chronic noncancer pain: a position paper of the American Academy of Neurology.

The Patient Safety Subcommittee requested a review of the science and policy issues regarding the rapidly emerging public health epidemic of prescription opioid-related morbidity and mortality in the United States. Over 100,000 persons have died, directly or indirectly, from prescribed opioids in the United States since policies changed in the late 1990s. In the highest-risk group (age 35-54 years), these deaths have exceeded mortality from both firearms and motor vehicle accidents. Whereas there is evidence for significant short-term pain relief, there is no substantial evidence for maintenance of pain relief or improved function over long periods of time without incurring serious risk of overdose, dependence, or addiction. The objectives of the article are to review the following: (1) the key initiating causes of the epidemic; (2) the evidence for safety and effectiveness of opioids for chronic pain; (3) federal and state policy responses; and (4) recommendations for neurologists in practice to increase use of best practices/universal precautions most likely to improve effective and safe use of opioids and to reduce the likelihood of severe adverse and overdose events.

Oral or transdermal opioids for osteoarthritis of the knee or hip.

Osteoarthritis is the most common form of joint disease and the leading cause of pain and physical disability in older people. Opioids may be a viable treatment option if people have severe pain or if other analgesics are contraindicated. However, the evidence about their effectiveness and safety is contradictory. This is an update of a Cochrane review first published in 2009. To determine the effects on pain, function, safety, and addiction of oral or transdermal opioids compared with placebo or no intervention in people with knee or hip osteoarthritis. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and CINAHL (up to 28 July 2008, with an update performed on 15 August 2012), checked conference proceedings, reference lists, and contacted authors. We included randomised or quasi-randomised controlled trials that compared oral or transdermal opioids with placebo or no treatment in people with knee or hip osteoarthritis. We excluded studies of tramadol. We applied no language restrictions. We extracted data in duplicate. We calculated standardised mean differences (SMDs) and 95% confidence intervals (CI) for pain and function, and risk ratios for safety outcomes. We combined trials using an inverse-variance random-effects meta-analysis. We identified 12 additional trials and included 22 trials with 8275 participants in this update. Oral oxycodone was studied in 10 trials, transdermal buprenorphine and oral tapentadol in four, oral codeine in three, oral morphine and oral oxymorphone in two, and transdermal fentanyl and oral hydromorphone in one trial each. All trials were described as double-blind, but the risk of bias for other domains was unclear in several trials due to incomplete reporting. Opioids were more beneficial in pain reduction than control interventions (SMD -0.28, 95% CI -0.35 to -0.20), which corresponds to a difference in pain scores of 0.7 cm on a 10-cm visual analogue scale (VAS) between opioids and placebo. This corresponds to a difference in improvement of 12% (95% CI 9% to 15%) between opioids (41% mean improvement from baseline) and placebo (29% mean improvement from baseline), which translates into a number needed to treat (NNTB) to cause one additional treatment response on pain of 10 (95% CI 8 to 14). Improvement of function was larger in opioid-treated participants compared with control groups (SMD -0.26, 95% CI -0.35 to -0.17), which corresponds to a difference in function scores of 0.6 units between opioids and placebo on a standardised Western Ontario and McMaster Universities Arthritis Index (WOMAC) disability scale ranging from 0 to 10. This corresponds to a difference in improvement of 11% (95% CI 7% to 14%) between opioids (32% mean improvement from baseline) and placebo (21% mean improvement from baseline), which translates into an NNTB to cause one additional treatment response on function of 11 (95% CI 7 to 14). We did not find substantial differences in effects according to type of opioid, analgesic potency, route of administration, daily dose, methodological quality of trials, and type of funding. Trials with treatment durations of four weeks or less showed larger pain relief than trials with longer treatment duration (P value for interaction = 0.001) and there was evidence for funnel plot asymmetry (P value = 0.054 for pain and P value = 0.011 for function). Adverse events were more frequent in participants receiving opioids compared with control. The pooled risk ratio was 1.49 (95% CI 1.35 to 1.63) for any adverse event (9 trials; 22% of participants in opioid and 15% of participants in control treatment experienced side effects), 3.76 (95% CI 2.93 to 4.82) for drop-outs due to adverse events (19 trials; 6.4% of participants in opioid and 1.7% of participants in control treatment dropped out due to adverse events), and 3.35 (95% CI 0.83 to 13.56) for serious adverse events (2 trials; 1.3% of participants in opioid and 0.4% of participants in control treatment experienced serious adverse events). Withdrawal symptoms occurred more often in opioid compared with control treatment (odds ratio (OR) 2.76, 95% CI 2.02 to 3.77; 3 trials; 2.4% of participants in opioid and 0.9% of participants control treatment experienced withdrawal symptoms). The small mean benefit of non-tramadol opioids are contrasted by significant increases in the risk of adverse events. For the pain outcome in particular, observed effects were of questionable clinical relevance since the 95% CI did not include the minimal clinically important difference of 0.37 SMDs, which corresponds to 0.9 cm on a 10-cm VAS.

Tratamiento del dolor irruptivo con fentanilo sublingual en pacientes con úlceras cutáneas crónicas

ObjectiveThe aim of the study was to assess the efficacy and safety of opioids in the management of pain in those patients with chronic cutaneous ulcers and breakthrough/incidental pain. Material and methodAn open-label, multicentre, prospective, uncontrolled study was conducted in the pain and ulcer units of 5 hospitals across the Comunidad Valenciana. Eligibility criteria were baseline pain 4 in the visual analogue scale or breakthrough procedural pain 4. Exclusion criteria were cognitive impairment, opioid intolerance, or patient refusal to provide informed consent. The protocol scheduled 5 controls: baseline (enrolment), 15 days, one month, 2 months, and 3 months. The main outcome measure of the study was the visual analogue scale score during rest, movement and procedures. Opioids were administered for release of the baseline pain, and sublingual fentanyl for breakthrough pain. ResultsA total of 32 patients (86.5%) completed the study. Baseline pain achieved a mean improvement of 3.6 visual analogue scale points (SD 2.3), movement pain improved by 3.9 points (SD 2.5) and procedural pain improved by 4.5 points (SD 2.8), and the mean pain intensity improvement was statistically significant from the first control and at all controls thereafter (P<.001). Nausea was reported by 14 patients (43.8%), drowsiness and constipation by 7 (21.9%), itching by 5 (15.6%), and one (3.1%) reported vomiting. ConclusionsStructured assessment of pain is a key concept in the management of patient with chronic cutaneous ulcers. The results of this study suggest that opioid therapy provides clinically significant pain relief with few adverse effects.

Safety of benzodiazepines and opioids in very severe respiratory disease: national prospective study

Objective To evaluate the safety of benzodiazepines and opioids in patients with very severe chronic obstructive pulmonary disease (COPD).Design Population based longitudinal consecutive cohort study.Setting Centres prescribing long term oxygen...

Systematic Literature Review and Meta-Analysis of the Efficacy and Safety of Prescription Opioids, Including Abuse-Deterrent Formulations, in Non-Cancer Pain Management

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. 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. 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]). ADFs and non-ADFs had comparable efficacy and safety profiles, while both were more efficacious than placebo in reducing pain intensity.

Long-term use of opioids for complex chronic pain

Increased opioid prescribing for back pain and other chronic musculoskeletal pain conditions has been accompanied by dramatic increases in prescription-opioid addiction and fatal overdose. Opioid-related risks appear to increase with dose. Although short-term randomised trials of opioids for chronic pain have found modest analgesic benefits (a one-third reduction in pain intensity on average), the long-term safety and effectiveness of opioids for chronic musculoskeletal pain remains unknown. Given the lack of large, long-term randomised trials, recent epidemiologic data suggest the need for caution when considering long-term use of opioids to manage chronic musculoskeletal pain, particularly at higher dosage levels. Principles for achieving more selective and cautious use of opioids for chronic musculoskeletal pain are proposed.

Comparative Safety of Benzodiazepines and Opioids Among Veterans Affairs Patients With Posttraumatic Stress Disorder

Although Veterans Affairs (VA) patients with posttraumatic stress disorder (PTSD) are prescribed benzodiazepines and opioids in addition to recommended pharmacotherapies, little is known about the safety of these medications. This study compared the 2-year incidence of adverse events among VA patients with PTSD exposed to combinations of selective serotonin reuptake inhibitors (SSRIs) or serotonin/norepinephrine reuptake inhibitors (SNRIs), benzodiazepines, and opioids. This retrospective cohort study used VA administrative data from 2004 to 2010 to identify and follow 5236 VA patients with PTSD with new episodes of (1) SSRIs/SNRIs only; (2) concurrent SSRIs/SNRIs and benzodiazepines; and (3) concurrent SSRIs/SNRIs, benzodiazepines, and opioids. Outcome measures were the 2-year incidence and adjusted hazard ratios (AHR) of mental health and medicine/surgery hospitalizations, emergency department visits, harmful events (eg, injuries and death), and any adverse event after adjustment for demographics, clinical covariates, and adverse event history. Compared with SSRIs/SNRIs only, the adjusted risk of mental health hospitalizations (AHR: 1.87; 95% confidence interval [CI]: 1.37-2.53) was greater among patients prescribed SSRIs/SNRIs and benzodiazepines concurrently. The AHR of mental health hospitalizations (AHR: 2.00; 95% CI: 1.35-2.98), medicine/surgery hospitalizations (AHR: 4.86; 95% CI: 3.30-7.14), emergency department visits (AHR: 2.01; 95% CI: 1.53-2.65), any harmful event (2.92; 95% CI: 2.21-3.84), and any adverse event (AHR: 2.65; 95% CI: 2.18-3.23) were all significantly greater among patients prescribed SSRIs/SNRIs, benzodiazepines, and opioids than among those prescribed SSRIs/SNRIs only. Concurrently prescribing SSRIs/SNRIs, benzodiazepines, and opioids among patients with PTSD is associated with adverse events. Although efforts are warranted to monitor patients who are prescribed combinations of these medications to prevent adverse events, these results should be interpreted with caution until they are replicated.

A population-based study on chronic pain and the use of opioids in Portugal

Although increasing doubts exist regarding the long-term effectiveness and safety of opioids in patients with chronic pain (CP), most guidelines still recognize opioids as an option in effective management of CP. We aimed to describe the prevalence and factors associated with opioid use in subjects with CP in Portugal and to evaluate satisfaction and self-assessed treatment effectiveness. A nationwide study was conducted in a representative sample of the adult Portuguese population. The 5094 participants were selected using random digit dialing and estimates were adequately weighted for the population. The prevalence of opioid use by subjects with CP was 4.37% (95% confidence interval [CI] 3.4–5.5); and in subjects experiencing CP with and without cancer, it was 10.13% and 4.24%, respectively. Use of strong opioids was reported by only 0.17% of CP subjects. Sex, pain severity and symptoms of depression and anxiety were significantly associated with opioid use; however, in multivariate modeling, only pain-related disability remained significant. No significant differences among users and nonusers of opioids were observed regarding treatment satisfaction and self-assessed effectiveness. Although extremely high rates of use of opioids exist in a few countries, it should not be seen as a ubiquitous problem. Indeed, we showed that in Portugal, as in many other regions in the world, opioids are used much less frequently than in those few countries. Moreover, we did not find significant differences among users and nonusers of opioids regarding satisfaction and self-assessed effectiveness, eventually showing the results to be in line with reports that show doubt about opioids’ effectiveness. Further research and particular attention to and continuous monitoring of the trends of use and abuse of opioids worldwide are recommended.

Opioids for acute pancreatitis pain

Acute pancreatitis is an acute inflammatory process of the pancreas that may also involve adjacent tissues and/or remote organ systems. Abdominal pain is the main symptom and is usually accompanied by nausea, vomiting and fever. Opoids are commonly used to manage pain in acute pancreatitis but there are still some uncertainties about their clinical effectiveness and safety. To assess the effectiveness and safety of opioids for treating acute pancreatitis pain. The search strategy included the Cochrane Upper Gastrointestinal and Pancreatic Diseases Review Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2013, Issue 6), MEDLINE (from 1950 to June 2013) and EMBASE (from 1980 to June 2013). There were no restrictions by language or publication status. We considered randomised clinical trials (RCTs) assessing the effectiveness of any opioid drug used for treating acute pancreatitis pain. Two review authors independently selected studies, assessed risks of bias and extracted data. We estimated risk ratios (RRs) for dichotomous data and calculated a 95% confidence interval (CI) for each RR. We performed an intention-to-treat (ITT) analysis. We undertook meta-analysis for some outcomes. We included five RCTs with a total of 227 participants (age range 23 to 76 years; 65% men) with acute pancreatitis pain. The opioids assessed were intravenous and intramuscular buprenorphine, intramuscular pethidine, intravenous pentazocine, transdermal fentanyl and subcutaneous morphine.One RCT, comparing subcutaneous morphine with intravenous metamizole reported non-significant reduction in the number of participants with improvements in pain intensity (primary outcome) (RR 0.50, 95% CI 0.19 to 1.33). Three studies compared analgesia using opioids with non-opioid treatments. After excluding one study that used opioids through continuous intravenous infusion, there was a decrease in the number of patients requiring supplementary analgesia (RR 0.53, 95% CI 0.30 to 0.93). In a single study, there were no differences in the number of patients requiring supplementary analgesia between buprenorphine and pethidine (RR 0.82, 95% CI 0.61 to 1.10).Pancreatitis complications were not associated with a significant difference between the drugs tested. No clinically serious or life-threatening adverse events occurred related to treatment. No differences for this outcome were found between opioid and non-opioid treatments, or for type of adverse event (nausea-vomiting and somnolence-sedation). One death in the procaine group was reported across all the trials.One RCT comparing pethidine with intramuscular buprenorphine reported non-significant differences of supplementary analgesic, adverse events or deaths. One RCT comparing fentanyl with placebo found no difference in adverse events.The findings of this review are limited by the lack of information to allow full appraisal of the risk of bias, the measurement of relevant outcomes and the small numbers of participants and events covered by the trials. Opioids may be an appropriate choice in the treatment of acute pancreatitis pain. Compared with other analgesic options, opioids may decrease the need for supplementary analgesia. There is currently no difference in the risk of pancreatitis complications or clinically serious adverse events between opioids and other analgesia options.Future research should focus on the design of trials with larger samples and the measurement of relevant outcomes for decision-making, such as the number of participants showing reductions in pain intensity. The reporting of these RCTs should also be improved to allow users of the medical literature to appraise their results accurately. Large longitudinal studies are also needed to establish the risk of pancreatitis complications and adverse events related to drugs.

Challenges in the Optimisation of Post-operative Pain Management with Opioids in Obese Patients: a Literature Review

An increasing number of obese patients are undergoing surgery, particularly bariatric and orthopaedic surgery. The physiological differences between obese and normal-weight subjects may modify not only anaesthetic requirements during surgery but also post-operative analgesic management, raising a number of challenges in a critical period. In this review, we analyse studies of post-operative pain management with opioids in obese subjects. We discuss the genetic factors common to pain and obesity and the factors potentially modifying opioid pharmacokinetics and pharmacodynamics in obese patients, and we analyse the overall efficacy and safety of opioids for pain management during the post-operative period in obese patients. Both modifications to surgical methods and additional analgesic treatments to decrease the requirement for opioids may improve early rehabilitation and quality of care and reduce adverse effects in obese patients.