Oral morphine for cancer pain

Effect of repeated intraperitoneal injections of different concentrations of oxycodone on immune function in mice

Background

The effect of oxycodone as an opioid receptor agonist on immune function is still controversial. In this study, we investigated the possible effects of oxycodone on immune function in mice and its possible mechanisms of action.

Methods

By repeated intraperitoneal injections of 25 mg/kg morphine and 5 mg/kg, 20 mg/kg, and 60 mg/kg oxycodone, we assessed possible changes in the number of splenic lymphocytes and inflammatory cytokines in the serum of mice. CD4+ T cells and CD8+ T cells were sorted from the spleen to observe whether the expression levels of opioid receptors and downstream signals were altered.

Results

Repeated administration of oxycodone at a dose above 20 mg/kg resulted in significant weight loss. Repeated administration of oxycodone exhibits significant dose-dependent reduction in CD4+ T cells, with little effect on CD8+ T cells and little effect on inflammatory cytokine levels. Low- and intermediate-dose oxycodone increased the mRNA expression level of MOR, KOR, and DOR to varying degrees. Moreover, oxycodone increases the mRNA expression levels of the TLR4 signaling pathway to varying degrees.

Conclusion

Repeated intraperitoneal injection of oxycodone induces immunosuppression in mice.

Opioid prescribing for cancer pain in Latin America: systematic review

OBJECTIVE

To explore opioid prescribing patterns for cancer pain in Latin America (LA).

METHODS

A systematic review was conducted adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Relevant databases, including MEDLINE, EMBASE, PubMed, LILACS and Scielo, were searched from inception to June 2023. Empirical studies of opioid prescription patterns in adult palliative care patients with cancer pain were included. Methodological quality was assessed using the Effective Public Health Practice Project tool. Data were analysed using narrative synthesis. Descriptive statistical analyses were conducted using SPSS V.28 (IBM). Categorical variables were summarised using frequencies and percentages and continuous variables as means or medians.

RESULTS

Seventeen studies from six countries were included. Ten were observational, while seven were experimental, including five randomised controlled trials (RCT) and two non-RCT. Most were low or moderate methodological quality. Out of 7809 patients, morphine (54%) and tramadol (18%) were the most prescribed opioids. The median of morphine equivalent daily dose was 26 mg (IQR 26-41).

CONCLUSION

Latin America shows lower opioid consumption rates compared with high-income countries for control pain management (CPM). More rigorous research on CPM in LA is needed. Additionally, a comprehensive review of opioid prescription patterns, including non-cancer diagnoses, is necessary.

Cannabinoids as a Potential Alternative to Opioids in the Management of Various Pain Subtypes: Benefits, Limitations, and Risks

INTRODUCTION

Pain is a global phenomenon encompassing many subtypes that include neuropathic, musculoskeletal, acute postoperative, cancer, and geriatric pain. Traditionally, opioids have been a mainstay pharmacological agent for managing many types of pain. However, opioids have been a subject of controversy with increased addiction, fatality rates, and cost burden on the US healthcare system. Cannabinoids have emerged as a potentially favorable alternative or adjunctive treatment for various types of acute and chronic pain. This narrative review seeks to describe the efficacy, risks, and benefits of cannabinoids as an adjunct or even potential replacement for opioids in the treatment of various subtypes of pain.

METHODS

In June of 2022, we performed a comprehensive search across multiple databases for English-language studies related to the use of cannabinoids in the treatment of various types pain: neuropathic pain, musculoskeletal pain, acute postoperative pain, cancer pain, and geriatric pain. Data from meta-analyses, systematic reviews, and randomized control trials (RCTs) were prioritized for reporting. We sought to focus our reported analysis on more recent literature as well as include older relevant studies with particularly notable findings.

RESULTS

There is conflicting evidence for the use of cannabinoids in the management of pain. While cannabinoids have shown efficacy in treating specific chronic pain subtypes such as neuropathic pain, fibromyalgia pain, and geriatric pain, they do not show as clear benefit in acute postoperative and the majority of musculoskeletal pain syndromes. Data trends towards cannabinoids having a positive effect in treating cancer pain, but results are not as conclusive. To date, there is a paucity of data comparing cannabinoids directly to opioids for pain relief. Overall, the side effects of cannabinoids appear to be relatively mild. However, there is still potential for addiction, altered brain development, psychiatric comorbidities, and drug-drug interactions.

CONCLUSION

Cannabinoids may be effective in specific subtypes of pain, but current evidence and guidelines do not yet support its use as the first-line treatment for any type of acute or chronic pain. Rather, it may be considered a good adjunct or alternative for patients who have failed more typical or conservative measures. Additional studies are needed with standardized forms of cannabinoids, route of delivery, and dosing for greater-powered analysis. Providers must weigh the individualized patient risks, benefits, and concurrent medication list in order to determine whether cannabinoids are appropriate for a patient's pain treatment plan.

Highlighting the hidden dangers of a 'weak' opioid: Deaths following use of dihydrocodeine in England (2001-2020)

BACKGROUND

Dihydrocodeine (DHC) is considered a 'weak' opioid, but there is evidence of its increasing misuse in overdose deaths. This research aims to analyse trends in DHC-related deaths in England relevant to source and dose of DHC, and decedent demographics.

METHODS

Cases from England reported to the National Programme on Substance Abuse Deaths (NPSAD) where DHC was identified at post-mortem and/or implicated in death between 2001 and 2020 were extracted for analysis.

RESULTS

2071 DHC-related deaths were identified. The greatest number of deaths involved illicitly obtained DHC and a significant increase in these deaths was recorded over time (r = 0.5, p = 0.03). However, there was a concurrent decline in the implication rate of DHC in causing death (r = -0.6, p < 0.01). Fatalities were primarily due to accidental overdose (64.8%) and misuse was highly prevalent in combination with additional central nervous system depressants (95.3%), namely illicit heroin/morphine and diazepam. In contrast, when DHC was obtained over-the-counter (OTC) suicide mortality accounted for almost half of the deaths (42.5%). Differences in polysubstance use were also identified, with less heroin/morphine and benzodiazepine co-detection, but increased OTC codeine co-detection.

CONCLUSIONS

DHC misuse in England is increasing. The pharmacological consideration of DHC as a 'weak' opioid may be misinterpreted by users, leading to accidental overdosing. There is an urgent need to understand increasing polypharmacy in overdose deaths. Additionally, suicides involving DHC is a potential cause for concern and a review of OTC opioid-paracetamol preparations is necessary to determine whether the benefits of these medications continue to outweigh the risks of intentional overdose.

Hydromorphone for cancer pain

BACKGROUND

This is an update of the original Cochrane Review first published in Issue 10, 2016. For people with advanced cancer, the prevalence of pain can be as high as 90%. Cancer pain is a distressing symptom that tends to worsen as the disease progresses. Evidence suggests that opioid pharmacotherapy is the most effective of these therapies. Hydromorphone appears to be an alternative opioid analgesic which may help relieve these symptoms.

OBJECTIVES

To determine the analgesic efficacy of hydromorphone in relieving cancer pain, as well as the incidence and severity of any adverse events.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and clinical trials registers in November 2020. We applied no language, document type or publication status limitations to the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared hydromorphone with placebo, an alternative opioid or another active control, for cancer pain in adults and children. Primary outcomes were participant-reported pain intensity and pain relief; secondary outcomes were specific adverse events, serious adverse events, quality of life, leaving the study early and death.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. We calculated risk ratio (RR) and 95% confidence intervals (CI) for binary outcomes on an intention-to-treat (ITT) basis. We estimated mean difference (MD) between groups and 95% CI for continuous data. We used a random-effects model and assessed risk of bias for all included studies. We assessed the evidence using GRADE and created three summary of findings tables.

MAIN RESULTS

With four new identified studies, the review includes a total of eight studies (1283 participants, with data for 1181 participants available for analysis), which compared hydromorphone with oxycodone (four studies), morphine (three studies) or fentanyl (one study). All studies included adults with cancer pain, mean age ranged around 53 to 59 years and the proportion of men ranged from 42% to 67.4%. We judged all the studies at high risk of bias overall because they had at least one domain with high risk of bias. We found no studies including children. We did not complete a meta-analysis for the primary outcome of pain intensity due to skewed data and different comparators investigated across the studies (oxycodone, morphine and fentanyl). Comparison 1: hydromorphone compared with placebo We identified no studies comparing hydromorphone with placebo. Comparison 2: hydromorphone compared with oxycodone Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured using a visual analogue scale (VAS)) in people treated with hydromorphone compared with those treated with oxycodone, but the evidence is very uncertain (3 RCTs, 381 participants, very low-certainty evidence). Participant-reported pain relief We found no studies reporting participant-reported pain relief. Specific adverse events We found no clear evidence of a difference in nausea (RR 1.13 95% CI 0.74 to 1.73; 3 RCTs, 622 participants), vomiting (RR 1.18, 95% CI 0.72 to 1.94; 3 RCTs, 622 participants), dizziness (RR 0.91, 95% CI 0.58 to 1.44; 2 RCTs, 441 participants) and constipation (RR 0.92, 95% CI 0.72 to 1.19; 622 participants) (all very low-certainty evidence) in people treated with hydromorphone compared with those treated with oxycodone, but the evidence is very uncertain. Quality of life We found no studies reporting quality of life. Comparison 3: hydromorphone compared with morphine Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured using the Brief Pain Inventory (BPI) or VAS)) in people treated with hydromorphone compared with those treated with morphine, but the evidence is very uncertain (2 RCTs, 433 participants; very low-certainty evidence). Participant-reported pain relief We found no clear evidence of a difference in the number of clinically improved participants, defined by 50% or greater pain relief rate, in the hydromorphone group compared with the morphine group, but the evidence is very uncertain (RR 0.99, 95% CI 0.84 to 1.18; 1 RCT, 233 participants; very low-certainty evidence). Specific adverse events At 24 days of treatment, morphine may reduce constipation compared with hydromorphone, but the evidence is very uncertain (RR 1.56, 95% CI 1.12 to 2.17; 1 RCT, 200 participants; very low-certainty evidence). We found no clear evidence of a difference in nausea (RR 0.94, 95% CI 0.66 to 1.30; 1 RCT, 200 participants), vomiting (RR 0.87, 95% CI 0.58 to 1.31; 1 RCT, 200 participants) and dizziness (RR 1.15, 95% CI 0.71 to 1.88; 1 RCT, 200 participants) (all very low-certainty evidence) in people treated with hydromorphone compared with those treated with morphine, but the evidence is very uncertain. Quality of life We found no studies reporting quality of life. Comparison 4: hydromorphone compared with fentanyl Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured by numerical rating scale (NRS)) at 60 minutes in people treated with hydromorphone compared with those treated with fentanyl, but the evidence is very uncertain (1 RCT, 82 participants; very low-certainty evidence). Participant-reported pain relief We found no studies reporting participant-reported pain relief. Specific adverse events We found no studies reporting specific adverse events. Quality of life We found no studies reporting quality of life.

AUTHORS' CONCLUSIONS

The evidence of the benefits and harms of hydromorphone compared with other analgesics is very uncertain. The studies reported some adverse events, such as nausea, vomiting, dizziness and constipation, but generally there was no clear evidence of a difference between hydromorphone and morphine, oxycodone or fentanyl for this outcome. There is insufficient evidence to support or refute the use of hydromorphone for cancer pain in comparison with other analgesics on the reported outcomes. Further research with larger sample sizes and more comprehensive outcome data collection is required.

Intrathecal Morphine Delivery at Cisterna Magna to Control Refractory Cancer-Related Pain: A Prospective Cohort Study

Background

For patients suffering from primary or metastatic cancer above the middle thoracic vertebrae, refractory pain management still remains a great challenge. Theoretically, inserting a catheter tip into the cisterna magna may be a promising solution. However, at present, there have been no reliable data regarding this novel technique. We therefore investigated the efficacy and safety of an advanced approach for pain relief in a specific population.

Methods

Thirty participants from two hospitals received the intrathecal deliveries of opioid to either one of two sites: cisterna magna (n = 15) or lower thoracic region (n = 15). Pain relief (visual analogue scale, VAS), quality of life (short form (36) health survey, SF-36) as well as depression (self-rating depression scale, SDS) were assessed in the follow-up visits and compared between the two groups.

Results

Patients receiving intrathecal morphine delivery to cisterna magna achieved greater pain improvement indicated as significant decrease of VAS scores at day 1 and 7, and achieved better improvement in physical function (day 7 and 30), role physical (day 7 and 30), body pain (day 7, 30 and 90), general health (day 7, 30 and 90), vitality (day 7, 30 and 90), social function (day 90), role emotional (day 7 and 90), mental health (day 7, 30 and 90) and SDS (day 1 and 7).

Conclusions

Intrathecal morphine delivery to cisterna magna might be an effective and safe technique for patients suffering from cancer at the middle thoracic vertebrae or above to control refractory pain. Trial registration: No. ChiCTR-ONN-17010681.

Pain Control in Latin America: The Optimized Role of Buprenorphine in the Treatment of Cancer and Noncancer Pain

Pain is a terrible health problem that transcends borders and nationalities, although there may be significant differences among regions regarding pain management. In Latin America (LatAm, composed of the many nations of Central America, South America, Mexico, and the Caribbean), access to healthcare, pain management, and opioid analgesics can vary. Despite an international U.S.-led trend toward greater control in opioid prescribing, the role of opioids in the management of severe pain in LatAm is probably smaller than it should be, as opioid consumption in LatAm overall is low. Buprenorphine is a strong opioidwith certain characteristics that make it a potentially useful analgesic agent in LatAm: it has a unique pharmacology that allows for transdermal administration and a favorable safety profile with a ceiling effect for respiratory depression. It has a well-studied low risk potential for misuse, and there is strong evidence for its safety and efficacy in managing both cancer and noncancer pain in adults. Caregivers and policy makers in LatAm may learn from the U.S. experience with opioids in order to develop protocols to better and safely manage pain, and it is possible that buprenorphine will play a key role.

Palliative Care in the Global Setting: ASCO Resource-Stratified Practice Guideline

Purpose

The purpose of this new resource-stratified guideline is to provide expert guidance to clinicians and policymakers on implementing palliative care of patients with cancer and their caregivers in resource-constrained settings and is intended to complement the Integration of Palliative Care Into Standard Oncology Care: American Society of Clinical Oncology Clinical Practice Guideline Update of 2016.

Methods

ASCO convened a multidisciplinary, multinational panel of experts in medical oncology, family medicine, radiation oncology, hematology/oncology, palliative and/or hospice care, pain and/or symptom management, patient advocacy, public health, and health economics. Guideline development involved a systematic literature review, a modified ADAPTE process, and a formal consensus-based process with the Expert Panel and additional experts (consensus ratings group).

Results

The systematic review included 48 full-text publications regarding palliative care in resource-constrained settings, along with cost-effectiveness analyses; the evidence for many clinical questions was limited. These provided indirect evidence to inform the formal consensus process, which resulted in agreement of ≥ 75% (by consensus ratings group including Expert Panel).

Recommendations

The recommendations help define the models of care, staffing requirements, and roles and training needs of team members in a variety of resource settings for palliative care. Recommendations also outline the standards for provision of psychosocial support, spiritual care, and opioid analgesics, which can be particularly challenging and often overlooked in resource-constrained settings. Additional information is available at www.asco.org/resource-stratified-guidelines.

It is the view of ASCO that health care providers and health care system decision makers should be guided by the recommendations for the highest stratum of resources available. The guideline is intended to complement but not replace local guidelines.

Irinotecan Alters the Disposition of Morphine Via Inhibition of Organic Cation Transporter 1 (OCT1) and 2 (OCT2)

PURPOSE

The organic cation transporters (OCTs) and multidrug and toxin extrusions (MATEs) together are regarded as an organic cation transport system critical to the disposition and response of many organic cationic drugs. Patient response to the analgesic morphine, a characterized substrate for human OCT1, is highly variable. This study was aimed to examine whether there is any organic cation transporter-mediated drug and drug interaction (DDI) between morphine and commonly co-administrated drugs.

METHODS

The uptake of morphine and its inhibition by six drugs which are commonly co-administered with morphine in the clinic were assessed in human embryonic kidney 293 (HEK293) cells stably expressing OCT1, OCT2 and MATE1. The in vivo interaction between morphine and the select irinotecan was determined by comparing the disposition of morphine in the absence versus presence of irinotecan treatment in mice.

RESULTS

The uptake of morphine in the stable HEK293 cells expressing human OCT1 and OCT2 was significantly increased by 3.56 and 3.04 fold, respectively, than that in the control cells, with no significant uptake increase in the cells expressing human MATE1. All of the six drugs examined, including amitriptyline, fluoxetine, imipramine, irinotecan, ondansetron, and verapamil, were inhibitors of OCT1/2-mediated morphine uptake. The select irinotecan significantly increased the plasma concentrations and decreased hepatic and renal accumulation of morphine in mice.

CONCLUSIONS

Morphine is a substrate of OCT1 and OCT2. Clinician should be aware that the disposition of and thus the response to morphine may be altered by co-administration of an OCT1/2 inhibitor, such as irinotecan.

Oligomerization and Catalytic Parameters of Human UDP-Glucuronosyltransferase 1A10: Expression and Characterization of the Recombinant Protein

UDP-glucuronosyltransferase (UGT), as an integral membrane protein localized in the endoplasmic reticulum, has the ability to detoxify potentially hazardous xenobiotic substances. Most UGTs are expressed in liver, but UGT1A10 has proven to be an extrahepatic enzyme considerably expressed throughout the gastrointestinal tract. Earlier studies indicated that different UGT isoforms could exist in higher-order homo-oligomers or at least dimers within the membrane, but the formation of intermolecular disulfide bridges between UGT molecules was not often observed. In this study, we expressed recombinant human UGT1A10 in human embryonic kidney (HEK)293 and Chinese hamster ovary (CHO) cells to examine its oligomeric states and characterize its enzymatic activities against two therapeutically interesting substrates, morphine and entacapone, including determination of the catalytic rate constant (k_cat) values for the first time. It was observed that a majority of the UGT1A10 protein expressed in HEK293 cells existed in covalently crosslinked higher-order oligomers via formation of intermolecular disulfide bonds, whereas formation of the intermolecular disulfide bonds was not observed in the UGT1A10 protein expressed in CHO cells. Owing to the formation of the covalently crosslinked higher-order oligomers, the UGT1A10 protein expressed in HEK293 cells had much lower catalytic activity (particularly the catalytic rate constant k_cat) against both morphine and entacapone, compared with the UGT1A10 protein form expressed in CHO cells against the same substrates.

[Dose-finding for treatment with a transdermal fentanyl patch : Titration with oral transmucosal fentanyl citrate and morphine sulfate]

To date, no studies investigating titration with oral transmucosal fentanyl for the dose-finding of transdermal fentanyl treatment have been published. In an open randomized study 60 patients with chronic malignant (n = 39) or nonmalignant pain (n = 21), who required opioid therapy according to step three of the guidelines of the World Health Organization (WHO), were investigated. In two groups of 30 patients each titration with immediate release morphine (IRM) or oral transmucosal fentanyl citrate (OTFC) was undertaken. For measurement purposes the Brief Pain Inventory (BPI) and Minimal Documentation System (MIDOS) were used. After a 24-h titration phase, in which patients documented the intensity of pain, nausea, and tiredness, treatment with transdermal fentanyl was evaluated over a 10-day period by means of the necessary dose adaptation (responder ≤ 1 dose adaptation; conversion formula 1:1 [OTFC group] vs 100:1 [IRM group]).The pain reduction over the first 24 h (titration phase) did not differ significantly between the groups. The number of responders (17 OTFC vs. 21 IRM) over the 10-day period did not show any difference either. In both groups there was a significant reduction in pain intensity (p < 0.001). Over the course of the study, there were significantly more drop-outs because of adverse effects in the OTFC group than in the IRM group (8 vs 1, p = 0.028).Oral transmucosal fentanyl citrate can be applied for the titration of transdermal fentanyl, but it does not show any clinically relevant advantage. For example, the risk of side effects-induced drop-outs was greater in the present study. Whether the unnecessary opioid switching to treat chronic pain and breakthrough pain is advantageous with regard to minimizing conversion errors cannot be definitively answered within the scope of this study.

Evidence-Based Palliative Care 13 Years On: Has anything changed?

There is a paucity of data on whether interventions in individual palliative care units are evidence-based. Thirteen years ago an initial study evaluated the evidence base of interventions in palliative care. Using similar methodology in the present study, we evaluated the evidence for interventions performed in an inpatient palliative care setting, looking at level of evidence as well as quality and outcome of evidence. More than half of all the interventions (47 interventions, 59 percent) we looked at in a Brisbane, Australia, inpatient palliative care setting were based on a high level of evidence in the form of systematic reviews of randomized controlled trials (level I or level II). There were only a few interventions (10 percent) for which no evidence could be retrieved. Our results show that the evidence base for interventions in palliative care continues to evolve, but that there are still areas for which further high-quality studies are needed.

Advanced cancer pain: the search for genetic factors correlated with interindividual variability in opioid requirement

AIM

To assess association between genetic variants and opioid requirement in cancer patients.

MATERIALS & METHODS

A prospective observational trial of 243 advanced cancer patients with inadequate analgesia treated by the palliative care team was analyzed for ABCB1, ARRB2, COMT, GCH1, IL1RN, KCNJ6, OPRM1, RHBDF2, SCN9A and Stat6 polymorphisms.

RESULTS

For patients carrying OPRM1 118AG/GG and COMT 472GG (Val158Val) or these genotypes alone, a significant higher median percentage dose increase was observed (95.2% [32.8-345]) compared with OPRM1 118AA and COMT 472GA/AA (158Met allele carriers; 48.5% [0-98.8]; p = 0.0016). No associations were found with morphine equivalent dose after consultation palliative care team or ketamine use.

CONCLUSION

Patients with the combined OPRM1 118AG/GG and COMT 472GG genotype required 50% higher dose increase for sufficient analgesia.

Tramadol with or without paracetamol (acetaminophen) for cancer pain

BACKGROUND

Tramadol is an opioid analgesic licensed for use in moderate to severe pain. It is considered as a low risk for abuse, so control regulations are not as stringent as for 'strong' opioids such as morphine. It has a potential role as a step 2 option of the World Health Organization (WHO) analgesic ladder.

OBJECTIVES

To assess the benefits and adverse effects of tramadol with or without paracetamol (acetaminophen) for cancer-related pain.

SEARCH METHODS

We searched the following databases using a wide range of search terms: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and LILACS. We also searched three clinical trials registry databases. The date of the last search was 2 November 2016.

SELECTION CRITERIA

We selected studies that were randomised, with placebo or active controls, or both, and included a minimum of 10 participants per treatment arm. We were interested particularly in blinded studies, but also included open studies.We excluded non-randomised studies, studies of experimental pain, case reports, and clinical observations.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data using a standard form and checked for agreement before entry into Review Manager 5. We included information about the number of participants treated and demographic details, type of cancer, drug and dosing regimen, study design (placebo or active control) and methods, study duration and follow-up, analgesic outcome measures and results, withdrawals, and adverse events. We collated multiple reports of the same study, so that each study, rather than each report, was the unit of interest in the review. We assessed the evidence using GRADE and created a 'Summary of findings' table.The main outcomes of interest for benefit were pain reduction of 30% or greater and 50% or greater from baseline, participants with pain no worse than mild, and participants feeling much improved or very much improved.

MAIN RESULTS

We included 10 studies (12 reports) with 958 adult participants. All the studies enrolled participants with chronic malignant tumour-related pain who were experiencing pain intensities described as moderate to severe, with most experiencing at least 4/10 with current treatment. The mean ages were 59 to 70 years, with participants aged between 24 and 87 years. Study length ranged from one day to six months. Five studies used a cross-over design. Tramadol doses ranged from 50 mg as single dose to 600 mg per day; doses of 300 mg per day to 400 mg per day were most common.Nine studies were at high risk of bias for one to four criteria (only one high risk of bias for size). We judged all the results to be very low quality evidence because of widespread lack of blinding of outcome assessment, inadequately described sequence generation, allocation concealment, and small numbers of participants and events. Important outcomes were poorly reported. There were eight different active comparators and one comparison with placebo. There was little information available for any comparison and no firm conclusions could be drawn for any outcome.Single comparisons of oral tramadol with codeine plus paracetamol, of dihydrocodeine, and of rectal versus oral tramadol provided no data for key outcomes. One study used tramadol combined with paracetamol; four participants received this intervention. One study compared tramadol with flupirtine - a drug that is no longer available. One study compared tramadol with placebo and a combination of cobrotoxin, tramadol, and ibuprofen, but the dosing schedule poorly explained.Two studies (191 participants) compared tramadol with buprenorphine. One study (131 participants) reported a similar proportion of no or mild pain at 14 days.Three studies (300 participants) compared tramadol with morphine. Only one study, combining tramadol, tramadol plus paracetamol, and paracetamol plus codeine as a single weak-opioid group reported results. Weak opioid produced reduction in pain of at least 30% from baseline in 55/117 (47%) participants, compared with 91/110 (82%) participants with morphine. Weak opioid produced reduction in pain of at least 50% in 49/117 (42%) participants, compared with 83/110 (75%) participants with morphine.There was no useful information for any other outcome of benefit or harm.

AUTHORS' CONCLUSIONS

There is limited, very low quality, evidence from randomised controlled trials that tramadol produced pain relief in some adults with pain due to cancer and no evidence at all for children. There is very low quality evidence that it is not as effective as morphine. This review does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different is very high. The place of tramadol in managing cancer pain and its role as step 2 of the WHO analgesic ladder is unclear.

Hydromorphone for cancer pain

BACKGROUND

Cancer pain is an important and distressing symptom that tends to increase in frequency and intensity as the cancer advances. For people with advanced cancer, the prevalence of pain can be as high as 90%. It has been estimated that 30% to 50% of people with cancer categorise their pain as moderate to severe, with between 75% and 90% of people with cancer experiencing pain that they describe as having a major impact on their daily life. Epidemiological studies suggest that approximately 15% of people with cancer pain fail to experience acceptable pain relief with conventional management. Uncontrolled pain can lead to physical and psychological distress and can, consequently, have a drastic effect on people's quality of life.

OBJECTIVES

To determine the analgesic efficacy of hydromorphone in relieving cancer pain, as well as the incidence and severity of any adverse events.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase and clinical trials registers up to April 2016. There were no language, document type or publication status limitations applied in the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared hydromorphone with placebo or other active pain medication for cancer pain in both adults and children. The four main outcomes selected have previously been identified as important to people with cancer; pain no worse than mild pain, and the impact of the treatment on consciousness, appetite and thirst. We did not consider physician-, nurse- or carer-reported measures of pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We used a random-effects model and assessed the risk of bias for all included studies. A meta-analysis was not completed on any of the primary outcomes in this review due to the lack of data. We assessed the evidence using GRADE and created two 'Summary of findings' tables.

MAIN RESULTS

We included four studies (604 adult participants), which compared hydromorphone to oxycodone (two studies) or morphine (two studies). Overall, the included studies were at low or unclear risk of bias, rated unclear due to unknown status of blinding of outcome assessment; we rated three studies at high risk of bias for potential conflict of interest. Data for 504 participants were available for analysis. We collected data on endpoint participant-reported pain intensity measured with a visual analogue scale (VAS) (mean ± standard deviation (SD): hydromorphone 28.86 ± 17.08, n = 19; oxycodone 30.30 ± 25.33, n = 12; scale from 0 to 100 with higher score indicating worse pain), and Brief Pain Inventory (BPI) 24 hours worst pain subscale (mean ± SD: hydromorphone 3.5 ± 2.9, n = 99; morphine 4.3 ± 3.0, n = 101, scale from 0 to 10 with higher score indicating worse pain). The data demonstrated a similar effect between groups with both comparisons. The pain intensity data showed that participants in all four trials achieved no worse than mild pain. There were several adverse events: some were the expected opioid adverse effects such as nausea, constipation and vomiting; others were not typical opioid adverse effects (for example, decreased appetite, dizziness and pyrexia, as shown in Table 1 in the main review), but generally showed no difference between groups. There were three deaths in the morphine group during the trial period, considered to be due to disease progression and unrelated to the drug. Three trials had over 10% dropout, but the reason and proportion of dropout was balanced between groups. The overall quality of evidence was very low mainly due to high risk of bias, imprecision of effect estimates and publication bias. There were no data available for children or for several participant-important outcomes, including participant-reported pain relief and treatment impact on consciousness, appetite or thirst.

AUTHORS' CONCLUSIONS

This review indicated little difference between hydromorphone and other opioids in terms of analgesic efficacy. Data gathered in this review showed that hydromorphone had a similar effect on participant-reported pain intensity as reported for oxycodone and morphine. Participants generally achieved no worse than mild pain after taking hydromorphone, which is comparable with the other drugs. It produced a consistent analgesic effect through the night and could be considered for use in people with cancer pain experiencing sleep disturbance. However, the overall quality of evidence was very low mainly due to risk of bias, imprecision of effect estimates and publication bias. This review only included four studies with limited sample size and a range of study designs. Data for some important outcomes, such as impact of the treatment on consciousness, appetite or thirst, were not available. Therefore, we were unable to demonstrate superiority or inferiority of hydromorphone in comparison with other analgesics for these outcomes. We recommend that further research with larger sample sizes and more comprehensive outcome data collection is required.

Intrathecal Morphine Infusion Therapy in Management of Chronic Pain: Present and Future Implementation in Korea

PURPOSE

Intrathecal morphine pump (ITMP) infusion therapy is efficient in managing malignant and nonmalignant chronic pain refractory to standard treatment. However, the high cost of an ITMP is the greatest barrier for starting a patient on ITMP infusion therapy. Using the revised Korean reimbursement guidelines, we investigated the cost effectiveness of ITMP infusion therapy and conducted a patient survey.

MATERIALS AND METHODS

A retrospective chart review of 12 patients who underwent ITMP implantation was performed. Morphine dose escalation rates were calculated, and numeric rating scale (NRS) scores were compared before and after ITMP implantation. We surveyed patients who were already using an ITMP as well as those who were candidates for an ITMP. All survey data were collected through in-person interviews over 3 months. Data on the cost of medical treatment were collected and projected over time.

RESULTS

The NRS score decreased during the follow-up period. The median morphine dose increased by 36.9% over the first year, and the median time required to reach a financial break-even point was 24.2 months. Patients were more satisfied with the efficacy of ITMP infusion therapy than with conventional therapy. The expected cost of ITMP implantation was KRW 4000000-5000000 in more than half of ITMP candidates scheduled to undergo implantation.

CONCLUSION

The high cost of initiating ITMP infusion therapy is challenging; however, the present results may encourage more patients to consider ITMP therapy.

Atrial Fibrillation is Associated With Morphine Treatment in Female Breast Cancer Patients: A Retrospective Population-Based Time-Dependent Cohort Study

We investigated the relationship between morphine treatment and the risk of atrial fibrillation (AF) in female patients with breast cancer. We identified a malignancy cohort of 73,917 female breast cancer patients without an AF history before the date of breast cancer diagnosis between 2000 and 2010 by using the Longitudinal Health Insurance Database for Catastrophic Illness Patients in Taiwan. This malignancy cohort was divided into morphine and comparison cohorts comprising 18,671 and 55,246 patients, respectively, and the incidences of newly diagnosed AF were calculated. We used the Cox proportional hazard model with time-dependent exposure covariates to estimate the risk of AF. The effect of morphine was assessed through multivariable Cox proportional hazard regression controlling for age, the Charlson comorbidity index (CCI) score, and the use of bisphosphonates and paclitaxel. Compared with nonmorphine users, patients who received morphine exhibited a 4.37-fold (95% CI = 3.56-5.36) increase in the risk of developing AF. The risk of AF increased as the CCI score increased, but decreased in patients with tamoxifen treatment. This risk is especially significant in current morphine users of all ages and with low CCI score. AF risk increased as the duration of morphine use lengthened (P for trend <0.0001). The incidence of AF in female breast cancer patients in Taiwan is associated with morphine, but prevented by tamoxifen treatment.

Buprenorphine for treating cancer pain

BACKGROUND

Many patients with cancer experience moderate to severe pain that requires treatment with strong analgesics. Buprenorphine, fentanyl and morphine are examples of strong opioids used for cancer pain relief. However, strong opioids are ineffective as pain treatment in all patients and are not well-tolerated by all patients. The aim of this Cochrane review is to assess whether buprenorphine is associated with superior, inferior or equal pain relief and tolerability compared to other analgesic options for patients with cancer pain.

OBJECTIVES

To assess the effectiveness and tolerability of buprenorphine for pain in adults and children with cancer.

SEARCH METHODS

We searched CENTRAL (the Cochrane Library) issue 12 or 12 2014, MEDLINE (via OVID) 1948 to 20 January 2015, EMBASE (via OVID) 1980 to 20 January 2015, ISI Web of Science (SCI-EXPANDED & CPCI-S) to 20 January 2015, ISI BIOSIS 1969 to 20 January 2015. We also searched ClinicalTrials.gov (http://clinicaltrials.gov/; metaRegister of Controlled Trials (mRCT) (http://www.controlled-trials.com/mrct/), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal (http://apps.who.int/trialsearch/) and the Proceedings of the Congress of the European Federation of International Association for the Study of Pain (IASP; via European Journal of Pain Supplements) on 16 February 2015. We checked the bibliographic references of identified studies as well as relevant studies and systematic reviews to find additional trials not identified by the electronic searches. We contacted authors of included studies for other relevant studies.

SELECTION CRITERIA

We included randomised controlled trials, with parallel-group or crossover design, comparing buprenorphine (any formulation and any route of administration) with placebo or an active drug (including buprenorphine) for cancer background pain in adults and children.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data pertaining to study design, participant details (including age, cancer characteristics, previous analgesic medication and setting), interventions (including details about titration) and outcomes, and independently assessed the quality of the included studies according to standard Cochrane methodology. As it was not feasible to meta-analyse the data, we summarised the results narratively. We assessed the overall quality of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

In this Cochrane review we identified 19 relevant studies including a total of 1421 patients that examined 16 different intervention comparisons.Of the studies that compared buprenorphine to another drug, 11 studies performed comparative analyses between the randomised groups, and five studies found that buprenorphine was superior to the comparison treatment. Three studies found no differences between buprenorphine and the comparison drug, while another three studies found treatment with buprenorphine to be inferior to the alternative treatment in terms of the side effects profile or patients preference/acceptability.Of the studies that compared different doses or formulations/routes of administration of buprenorphine, pain intensity ratings did not differ significantly between intramuscular buprenorphine and buprenorphine suppository. However, the average severity of dizziness, nausea, vomiting and adverse events as a total were all significantly higher in the intramuscular group relatively to the suppository group (one study).Sublingual buprenorphine was associated with faster onset of pain relief compared to subdermal buprenorphine, with similar duration analgesia and no significant differences in adverse event rates reported between the treatments (one study).In terms of transdermal buprenorphine, two studies found it superior to placebo, whereas a third study found no difference between placebo and different doses of transdermal buprenorphine.The studies that examined different doses of transdermal buprenorphine did not report a clear dose-response relationship.The quality of this evidence base was limited by under-reporting of most bias assessment items (e.g., the patient selection items), by small sample sizes in several included studies, by attrition (with data missing from 8.2% of the enrolled/randomised patients for efficacy and from 14.6% for safety) and by limited or no reporting of the expected outcomes in a number of cases. The evidence for all the outcomes was very low quality.

AUTHORS' CONCLUSIONS

Based on the available evidence, it is difficult to say where buprenorphine fits in the treatment of cancer pain with strong opioids. However, it might be considered to rank as a fourth-line option compared to the more standard therapies of morphine, oxycodone and fentanyl, and even there it would only be suitable for some patients. However, palliative care patients are often heterogeneous and complex, so having a number of analgesics available that can be given differently increases patient and prescriber choice. In particular, the sublingual and injectable routes seemed to have a more definable analgesic effect, whereas the transdermal route studies left more questions.

Buprenorphine for treating cancer pain

BACKGROUND

Many patients with cancer experience moderate to severe pain that requires treatment with strong analgesics. Buprenorphine, fentanyl and morphine are examples of strong opioids used for cancer pain relief. However, strong opioids are ineffective as pain treatment in all patients and are not well-tolerated by all patients. The aim of this Cochrane review is to assess whether buprenorphine is associated with superior, inferior or equal pain relief and tolerability compared to other analgesic options for patients with cancer pain.

OBJECTIVES

To assess the effectiveness and tolerability of buprenorphine for pain in adults and children with cancer.

SEARCH METHODS

We searched CENTRAL (the Cochrane Library) issue 12 or 12 2014, MEDLINE (via OVID) 1948 to 20 January 2015, EMBASE (via OVID) 1980 to 20 January 2015, ISI Web of Science (SCI-EXPANDED & CPCI-S) to 20 January 2015, ISI BIOSIS 1969 to 20 January 2015. We also searched ClinicalTrials.gov (http://clinicaltrials.gov/; metaRegister of Controlled Trials (mRCT) (http://www.controlled-trials.com/mrct/), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal (http://apps.who.int/trialsearch/) and the Proceedings of the Congress of the European Federation of International Association for the Study of Pain (IASP; via European Journal of Pain Supplements) on 16 February 2015. We checked the bibliographic references of identified studies as well as relevant studies and systematic reviews to find additional trials not identified by the electronic searches. We contacted authors of included studies for other relevant studies.

SELECTION CRITERIA

We included randomised controlled trials, with parallel-group or crossover design, comparing buprenorphine (any formulation and any route of administration) with placebo or an active drug (including buprenorphine) for cancer background pain in adults and children.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data pertaining to study design, participant details (including age, cancer characteristics, previous analgesic medication and setting), interventions (including details about titration) and outcomes, and independently assessed the quality of the included studies according to standard Cochrane methodology. As it was not feasible to meta-analyse the data, we summarised the results narratively. We assessed the overall quality of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

In this Cochrane review we identified 19 relevant studies including a total of 1421 patients that examined 16 different intervention comparisons.Of the studies that compared buprenorphine to another drug, 11 studies performed comparative analyses between the randomised groups, and five studies found that buprenorphine was superior to the comparison treatment. Three studies found no differences between buprenorphine and the comparison drug, while another three studies found treatment with buprenorphine to be inferior to the alternative treatment in terms of the side effects profile or patients preference/acceptability.Of the studies that compared different doses or formulations/routes of administration of buprenorphine, pain intensity ratings did not differ significantly between intramuscular buprenorphine and buprenorphine suppository. However, the average severity of dizziness, nausea, vomiting and adverse events as a total were all significantly higher in the intramuscular group relatively to the suppository group (one study).Sublingual buprenorphine was associated with faster onset of pain relief compared to subdermal buprenorphine, with similar duration analgesia and no significant differences in adverse event rates reported between the treatments (one study).In terms of transdermal buprenorphine, two studies found it superior to placebo, whereas a third study found no difference between placebo and different doses of transdermal buprenorphine.The studies that examined different doses of transdermal buprenorphine did not report a clear dose-response relationship.The quality of this evidence base was limited by under-reporting of most bias assessment items (e.g., the patient selection items), by small sample sizes in several included studies, by attrition (with data missing from 8.2% of the enrolled/randomised patients for efficacy and from 14.6% for safety) and by limited or no reporting of the expected outcomes in a number of cases. The evidence for all the outcomes was very low quality.

AUTHORS' CONCLUSIONS

Based on the available evidence, it is difficult to say where buprenorphine fits in the treatment of cancer pain with strong opioids. However, it might be considered to rank as a fourth-line option compared to the more standard therapies of morphine, oxycodone and fentanyl, and even there it would only be suitable for some patients. However, palliative care patients are often heterogeneous and complex, so having a number of analgesics available that can be given differently increases patient and prescriber choice. In particular, the sublingual and injectable routes seemed to have a more definable analgesic effect, whereas the transdermal route studies left more questions.

Palliative care in Thailand

In Thailand, several barriers exist that prevent people with life-limiting illnesses from accessing good-quality palliative care, namely: lack of palliative care providers; lack of training and education for the palliative care workforce; and issues with availability and distribution of opioids. Without palliative care, people suffer needlessly during the last months of their life. This paper gives an analysis of these issues and provides recommendations for clinical practice, research and health policy that may help to alleviate these issues.

Cross-sectional pilot study to monitor the availability, dispensed prices, and affordability of opioids around the globe

CONTEXT

Opioids are essential medicines. The World Health Organization and Health Action International monitor the price of essential medicines. However, their surveys do not include opioids, and there is no information on their affordability.

OBJECTIVES

To provide information on access to pain treatment, as measured by the availability and dispensed price of five opioids in 13 formulations, and the affordability of oral immediate-release (IR) morphine.

METHODS

The International Association for Hospice and Palliative Care members were distributed by their countries' Gross National Income (GNI) level using the World Bank categories, i.e., high income country (HIC), upper middle income country (UMIC), lower middle income country (LMIC), low income country (LIC), and randomized. A total of 10 participants were selected from each (n=40) domain. Participants were asked to identify a pharmacy located closest to a public facility that provides diagnosis/treatment for life-threatening conditions and report the lowest dispensed price of the smallest selling unit and strength of each formulation. Availability and median (Me) price were calculated for each. Affordability and percentage of international buyer price (IBP) were calculated for morphine oral solid IR.

RESULTS

A total of 30 participants from 26 countries (response rate=75%) responded. Significant correlation was found between availability and GNI (range: 65-68% [HIC and LIC]; R=0.781; P<0.0001). Injectable and morphine oral solid sustained release (SR) were the most available (59% and 55%). Methadone (oral) was the least expensive (Me=0.5) followed by fentanyl (transdermal; Me=2.2). The Me price for morphine oral solid IR and ratios between dispensed and IBP were lower in HIC than in LMIC (price=0.03 vs. 0.16; ratio=2.23 vs. 0.03). Affordability for morphine oral solid IR was five days (Me=0.1; range=29-0.25).

CONCLUSION

Patients in LMIC and LIC have limited access to opioids, and there are subsidies in place for more expensive medications and formulations in all GNI levels, but not for morphine oral solid IR. Additional research is necessary to identify the reasons behind these findings.

Codeine, alone and with paracetamol (acetaminophen), for cancer pain

BACKGROUND

Pain is very common in patients with cancer. Opioid analgesics, including codeine, play a significant role in major guidelines on the management of cancer pain, particularly for mild to moderate pain. Codeine is widely available and inexpensive, which may make it a good choice, especially in low-resource settings. Its use is controversial, in part because codeine is not effective in a minority of patients who cannot convert it to its active metabolite (morphine), and also because of concerns about potential abuse, and safety in children.

OBJECTIVES

To determine the efficacy and safety of codeine used alone or in combination with paracetamol for relieving cancer pain.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2014, Issue 2), MEDLINE and EMBASE from inception to 5 March 2014, supplemented by searches of clinical trial registries and screening of the reference lists of the identified studies and reviews in the field.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials using single or multiple doses of codeine, with or without paracetamol, for the treatment of cancer pain. Trials could have either parallel or cross-over design, with at least 10 participants per treatment group. Studies in children or adults reporting on any type, grade, and stage of cancer were eligible. We accepted any formulation, dosage regimen, and route of administration of codeine, and both placebo and active controls.

DATA COLLECTION AND ANALYSIS

Two review authors independently read the titles and abstracts of all studies identified by the searches and excluded those that clearly did not meet the inclusion criteria. For the remaining studies, two authors read the full manuscripts and assessed them for inclusion. We resolved discrepancies between review authors by discussion. Included studies were described qualitatively, since no meta-analysis was possible because of the small amount of data identified, and clinical and methodological between-study heterogeneity.

MAIN RESULTS

We included 15 studies including 721 participants with cancer pain due to diverse types of malignancy. All studies were performed on adults; there were no studies on children. The included studies were of adequate methodological quality, but all except for one were judged to be at a high risk of bias because of small study size, and six because of methods used to deal with missing data or high withdrawal rates. Three studies used a parallel group design; the remainder were cross-over trials in which there was an adequate washout period, but only one reported results for treatment periods separately.Twelve studies used codeine as a single agent and three combined it with paracetamol. Ten studies included a placebo arm, and 14 included one or more of 16 different active drug comparators or compared different routes of administration. Most studies investigated the effect of a single dose of medication, while five used treatment periods of one, seven or 21 days. Most studies used codeine at doses of 30 mg to 120 mg.There were insufficient data for any pooled analysis. Only two studies reported our preferred responder outcome of 'participants with at least 50% reduction in pain' and two reported 'participants with no worse than mild pain'. Eleven studies reported treatment group mean measures of pain intensity or pain relief; overall for these outcome measures, codeine or codeine plus paracetamol was numerically superior to placebo and equivalent to the active comparators.Adverse event reporting was poor: only two studies reported the number of participants with any adverse event specified by treatment group and only one reported the number of participants with any serious adverse event. In multiple-dose studies nausea, vomiting and constipation were common, with somnolence and dizziness frequent in the 21-day study. Withdrawal from the studies, where reported, was less than 10% except in two studies. There were three deaths, in all cases due to the underlying cancer.

AUTHORS' CONCLUSIONS

We identified only a small amount of data in studies that were both randomised and double-blind. Studies were small, of short duration, and most had significant shortcomings in reporting. The available evidence indicates that codeine is more effective against cancer pain than placebo, but with increased risk of nausea, vomiting, and constipation. Uncertainty remains as to the magnitude and time-course of the analgesic effect and the safety and tolerability in longer-term use. There were no data for children.

Efficacy and safety profile of combination of tramadol-diclofenac versus tramadol-paracetamol in patients with acute musculoskeletal conditions, postoperative pain, and acute flare of osteoarthritis and rheumatoid arthritis: a Phase III, 5-day open-label study

Objective

We aimed to evaluate the safety and efficacy of a fixed-dose combination (FDC) of tramadol and diclofenac versus a standard approved FDC of tramadol and paracetamol, in patients with acute moderate to severe pain.

Methods

A total of 204 patients with moderate to severe pain due to acute musculoskeletal conditions (n=52), acute flare of osteoarthritis (n=52), acute flare of rheumatoid arthritis (n=50), or postoperative pain (n=50) were enrolled in the study at baseline. Each disease category was then randomized to receive either of two treatments for 5 days: group A received an FDC of immediate-release tramadol hydrochloride (50 mg) and sustained-release diclofenac sodium (75 mg) (one tablet, twice daily), and group B received an FDC of tramadol hydrochloride (37.5 mg) and paracetamol (325 mg) (two tablets every 4–6 hours, up to a maximum of eight tablets daily). The primary efficacy end points were reductions in pain intensity from baseline at day 3 and day 5 as assessed by a Visual Analog Scale (VAS) score.

Results

Group A showed a significant reduction in the VAS score for overall pain from baseline on day 3 (P=0.001) and day 5 (P<0.0001) as compared with group B. The combination of tramadol-diclofenac resulted in few mild to moderate adverse events (nausea, vomiting, epigastric pain, and gastritis), which required minimal management, without any treatment discontinuation. The number of adverse events in group A was nine (8.82%) compared with 22 (21.78%) in group B, after 5 days of treatment.

Conclusion

An FDC of tramadol-diclofenac showed a significantly greater reduction in pain intensity and was well tolerated compared with tramadol-paracetamol, resulting in better analgesia in patients suffering from moderate to severe pain due to acute musculoskeletal conditions, postoperative pain following orthopedic surgery, or acute flare of osteoarthritis and rheumatoid arthritis.

Impact of morphine, fentanyl, oxycodone or codeine on patient consciousness, appetite and thirst when used to treat cancer pain

BACKGROUND

There is increasing focus on providing high quality care for people at the end of life, irrespective of disease or cause, and in all settings. In the last ten years the use of care pathways to aid those treating patients at the end of life has become common worldwide. The use of the Liverpool Care Pathway in the UK has been criticised. In England the LCP was the subject of an independent review, commissioned by a Health Minister. The Neuberger Review acknowledged that the LCP was based on the sound ethical principles that provide the basis of good quality care for patients and families when implemented properly. It also found that the LCP often was not implemented properly, and had instead become a barrier to good care; it made over 40 recommendations, including education and training, research and development, access to specialist palliative care services, and the need to ensure care and compassion for all dying patients. In July 2013, the Department of Health released a statement that stated the use of the LCP should be "phased out over the next 6-12 months and replaced with an individual approach to end of life care for each patient".The impact of opioids was a particular concern because of their potential influence on consciousness, appetite and thirst in people near the end of life. There was concern that impaired patient consciousness may lead to an earlier death, and that effects of opioids on appetite and thirst may result in unnecessary suffering. This rapid review, commissioned by the National Institute for Health Research, used standard Cochrane methodology to examine adverse effects of morphine, fentanyl, oxycodone, and codeine in cancer pain studies as a close approximation to possible effects in the dying patient.

OBJECTIVES

To determine the impact of opioid treatment on patient consciousness, appetite and thirst in randomised controlled trials of morphine, fentanyl, oxycodone or codeine for treating cancer pain.

SEARCH METHODS

We assessed adverse event data reported in studies included in current Cochrane reviews of opioids for cancer pain: specifically morphine, fentanyl, oxycodone, and codeine.

SELECTION CRITERIA

We included randomised studies using multiple doses of four opioid drugs (morphine, fentanyl, oxycodone, and codeine) in cancer pain. These were taken from four existing or ongoing Cochrane reviews. Participants were adults aged 18 and over. We included only full journal publication articles.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted adverse event data, and examined issues of study quality. The primary outcomes sought were numbers of participants experiencing adverse events of reduced consciousness, appetite, and thirst. Secondary outcomes were possible surrogate measures of the primary outcomes: delirium, dizziness, hallucinations, mood change and somnolence relating to patient consciousness, and nausea, vomiting, constipation, diarrhoea, dyspepsia, dysphagia, anorexia, asthenia, dehydration, or dry mouth relating to appetite or thirst.Comparative measures of harm were known to be unlikely, and we therefore calculated the proportion of participants experiencing each of the adverse events of interest with each opioid, and for all four opioid drugs combined.

MAIN RESULTS

We included 77 studies with 5619 randomised participants. There was potential bias in most studies, with small size being the most common; individual treatment groups had fewer than 50 participants in 60 studies. Participants were relatively young, with mean age in the studies typically between 50 and 70 years. Multiple major problems with adverse event reporting were found, including failing to report adverse events in all participants who received medication, all adverse events experienced, how adverse events were collected, and not defining adverse event terminology or whether a reporting system was used.Direct measures of patient consciousness, patient appetite, or thirst were not apparent. For opioids used to treat cancer pain adverse event incidence rates were 25% for constipation, 23% for somnolence, 21% for nausea, 17% for dry mouth, and 13% for vomiting, anorexia, and dizziness. Asthenia, diarrhoea, insomnia, mood change, hallucinations and dehydration occurred at incidence rates of 5% and below.

AUTHORS' CONCLUSIONS

We found no direct evidence that opioids affected patient consciousness, appetite or thirst when used to treat cancer pain. However, somnolence, dry mouth, and anorexia were common adverse events in people with cancer pain treated with morphine, fentanyl, oxycodone, or codeine.We are aware that there is an important literature concerning the problems that exist with adverse event measurement, reporting, and attribution. Together with the known complications concerning concomitant medication, data collection and reporting, and nomenclature, this means that these adverse events cannot always be attributed unequivocally to the use of opioids, and so they provide only a broad picture of adverse events with opioids in cancer pain. The research agenda includes developing definitions for adverse events that have a spectrum of severity or importance, and the development of appropriate measurement tools for recording such events to aid clinical practice and clinical research.

Transdermal fentanyl for cancer pain

BACKGROUND

Opioid drugs have been used for many years to relieve pain. Transdermal fentanyl offers one option for delivering and maintaining pain relief in patients with moderate or severe cancer pain.

OBJECTIVES

To determine the analgesic efficacy of transdermal fentanyl for relief of cancer pain, and to assess the adverse events associated with the use of transdermal fentanyl for relief of cancer pain.

SEARCH METHODS

The following databases were searched: Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 4 of 12); MEDLINE (1966 to May 2013); EMBASE (1974 to May 2013; CANCERLIT (PubMED) (November 2012); and ClinicalTrials.gov (May 2013).

SELECTION CRITERIA

Published randomised controlled trials (RCTs) using placebo or active comparators reporting on the analgesic effect of transdermal fentanyl in adults and children with cancer pain. Studies with fewer than 10 participants were excluded.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors. We extracted any available data on the number or proportion of patients with 'no worse than mild pain' or treatment success (very satisfied, or very good or excellent on patient global impression scales), together with information about adverse events and withdrawals.

MAIN RESULTS

We identified nine studies meeting the inclusion criteria, including a Turkish study that is awaiting formal translation. There were 1244 participants randomised in classically designed RCTs, of whom 1197 had evaluable data, and 138 patients enrolled in an enriched enrolment, randomised withdrawal (EERW) trial. Overall, 600 participants were treated with transdermal fentanyl patches, 382 with various formulations of morphine, 36 with methadone, and 221 with paracetamol plus codeine. There were major sources of potential bias, including lack of blinding, small size, high levels of attrition, and inconsistent reporting.We could not compare data in a meaningful analysis regarding adverse events such as nausea, abdominal pain, gastrointestinal bleeding, and confusion. These events may have been attributable to the underlying disease process.There were insufficient comparable data for meta-analysis to be undertaken or to produce numbers needed to treat (NNT) for the analgesic effect. In seven studies with 461 participants reporting pain intensity results after about two weeks, the mean or median pain scores were on the borderline of mild and moderate pain. Most participants would have had no worse than mild pain on treatment. Another reported that 77% of participants using transdermal fentanyl had an undefined successful outcome. Fewer participants experienced constipation with transdermal fentanyl (28%) than with oral morphine (46%), giving a risk ratio of 0.61 (95% CI 0.47 to 0.78); the NNT to prevent constipation was 5.5 (95% CI 3.8 to 10).

AUTHORS' CONCLUSIONS

The randomised trial literature for effectiveness of transdermal fentanyl is limited, but it is an important medicine. Most studies recruited fewer than 100 participants and did not provide data appropriate for meta-analysis. Only a few reported how many patients had good pain relief but, where data were reported, a majority had no worse than mild pain within a reasonably short time period. The evidence pointed to a useful and significant reduction in complaints about constipation for transdermal fentanyl compared with oral morphine.