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Journal of Pain & Palliative Care... Dec 2016We conducted a systematic review to evaluate worldwide human English published literature from 2009 to 2014 on prevalence of opioid misuse/abuse in retrospective... (Review)
Review
We conducted a systematic review to evaluate worldwide human English published literature from 2009 to 2014 on prevalence of opioid misuse/abuse in retrospective databases where International Classification of Diseases (ICD) codes were used. Inclusion criteria for the studies were use of a retrospective database, measured abuse, dependence, and/or poisoning using ICD codes, stated prevalence or it could be derived, and documented time frame. A meta-analysis was not performed. A qualitative narrative synthesis was used, and 16 studies were included for data abstraction. ICD code use varies; 10 studies used ICD codes that encompassed all three terms: abuse, dependence, or poisoning. Eight studies limited determination of misuse/abuse to an opioid user population. Abuse prevalence among opioid users in commercial databases using all three terms of ICD codes varied depending on the opioid; 21 per 1000 persons (reformulated extended-release oxymorphone; 2011-2012) to 113 per 1000 persons (immediate-release opioids; 2010-2011). Abuse prevalence in general populations using all three ICD code terms ranged from 1.15 per 1000 persons (commercial; 6 months 2010) to 8.7 per 1000 persons (Medicaid; 2002-2003). Prevalence increased over time. When similar ICD codes are used, the highest prevalence is in US government-insured populations. Limiting population to continuous opioid users increases prevalence. Prevalence varies depending on ICD codes used, population, time frame, and years studied. Researchers using ICD codes to determine opioid abuse prevalence need to be aware of cautions and limitations.
Topics: Analgesics, Opioid; Databases, Factual; Humans; International Classification of Diseases; Opioid-Related Disorders; Prescription Drug Misuse; Prevalence
PubMed: 27802072
DOI: 10.1080/15360288.2016.1231739 -
Pain Physician May 2016Opioid overdose continues to be a significant and growing cause of preventable mortality and morbidity. Studies suggest that unintentional, non-fatal overdose from... (Review)
Review
BACKGROUND
Opioid overdose continues to be a significant and growing cause of preventable mortality and morbidity. Studies suggest that unintentional, non-fatal overdose from prescription opioid analgesics constitutes a large portion of total overdose events. The societal burden associated with these events is a frequently overlooked public health concern.
OBJECTIVES
To evaluate unintentional, non-fatal prescription opioid overdoses, including the identification of risk factors, societal burden, and knowledge gaps where further study is warranted.
STUDY DESIGN
Systematic review of the literature for unintentional, non-fatal opioid overdose.
METHODS
Preferred reporting items for systematic reviews and meta-analyses guidelines were used in constructing this systematic review. To determine the scope of the existing literature, a systematic search was conducted using the MEDLINE, CINAHL, PsycINFO, and Web of Science databases.
RESULTS
This systematic review analyzes 24 articles (21 retrospective descriptive analyses, 2 prospective analyses, one phase III trial, and one meta-analysis). Articles were reviewed by authors and relevant data examined. Results show that opioid overdose morbidity is significantly more prevalent than mortality and sequelae of non-fatal events should be studied in more detail.
LIMITATIONS
The limitations of this systematic review include the range of study populations and opioids discussed and the broad and variable definitions of "opioid overdose" in the literature.
CONCLUSIONS
Opioid overdose morbidity and mortality is seen across the entire spectrum of inpatient and outpatient use with significant numbers of adverse events occurring in population segments not identified by high risk indicators. Increased physician awareness and a multi-modal approach could help mitigate the overdose epidemic while maintaining effective pain control for patients.
KEY WORDS
Prescription, opioid, accidental drug overdose, unintentional overdose, drug poisoning, fentanyl, oxycodone, hydrocodone, methadone, oxymorphone, hydromorphone.
Topics: Analgesics, Opioid; Drug Overdose; Humans; Prescription Drug Overuse
PubMed: 27228510
DOI: No ID Found -
The Cochrane Database of Systematic... May 2015Agitation 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... (Review)
Review
BACKGROUND
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.
OBJECTIVES
To determine the clinical efficacy and safety of opioids for agitation in people with dementia.
SEARCH METHODS
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.
SELECTION CRITERIA
Randomised, controlled trials of opioids compared to placebo for agitation in people with dementia.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed the studies identified by the search against the inclusion criteria.
MAIN RESULTS
There are currently no completed randomised, placebo controlled trials of opioids for agitation in dementia. There are two potentially relevant trials still in progress.
AUTHORS' CONCLUSIONS
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.
Topics: Analgesics, Opioid; Dementia; Humans; Psychomotor Agitation
PubMed: 25972091
DOI: 10.1002/14651858.CD009705.pub2 -
Schmerz (Berlin, Germany) Feb 2015The efficacy and safety of opioid therapy in chronic low back pain (CLBP) is under debate. We updated a recent systematic review on the efficacy and safety of opioids in... (Comparative Study)
Comparative Study Meta-Analysis Review
[Opioids in chronic low back pain. A systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks duration].
BACKGROUND
The efficacy and safety of opioid therapy in chronic low back pain (CLBP) is under debate. We updated a recent systematic review on the efficacy and safety of opioids in CLBP.
METHODS
We screened MEDLINE, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL) up until October 2013, as well as reference sections of original studies and systematic reviews of randomized controlled trials (RCTs) of opioids in CLBP. We included double-blind randomized placebo-controlled studies of at least 4 weeks duration. Using a random effects model, absolute risk differences (RD) were calculated for categorical data and standardized mean differences (SMD) for continuous variables.
RESULTS
We included 12 RCTs with 17 treatment arms and 4375 participants. Median study duration was 12 (4-16) weeks. Of the 17 treatment arms, seven (41.2 %) used oxycodone; four (23.6 %) tramadol; buprenorphine and oxymorphone were each used in two (11.8 %) and hydromorphone and tapentadol each in one (5.8 %). The results for studies with parallel/cross-over design were as follows (with 95 % confidence interval, CI): opioids were superior to placebo in reducing pain intensity (SMD - 0.29 [- 0.37, - 0.21], p < 0.0001; six studies with 2896 participants). Opioids were superior to placebo in 50 % pain reduction (RD 0.05 [0.01, 0.10], p = 0.01; two studies with 1492 participants; number needed to benefit (NNTB) 19 [95 % CI 10-107]). Opioids were not superior to placebo in reports of much or very much improved pain (RD 0.16 [- 0.01, 0.34], p = 0.07; two studies with 1153 participants). Opioids were superior to placebo in improving physical functioning (SMD - 0.22 [- 0.31, - 0.12], p < 0.0001; four studies with 1895 participants). Patients dropped out less frequently with opioids than with placebo due to lack of efficacy (RD - 0.10 [- 0.16, - 0.04], p = 0.001; five studies with 3168 participants; NNTB 10 [8-13]). Patients dropped out more frequently with opioids than with placebo due to adverse events (RD 0.12 [0.05, 0.19], p = 0.0007; six studies with 2910 participants; number needed to harm (NNTH) 7 [95 % CI 6-8]). There was no significant difference between opioids and placebo in terms of the frequency of serious adverse events or deaths.
CONCLUSION
Opioids were superior to placebo in terms of efficacy and inferior in terms of tolerability. Opioids and placebo did not differ in terms of safety during the study period. The conclusion on the safety of opioids compared to placebo is limited by the low number of serious adverse events and deaths. Short-term and intermediate-term opioid therapy may be considered in selected CLBP patients. The English full-text version of this article is freely available at SpringerLink (under "Supplemental").
Topics: Activities of Daily Living; Analgesics, Opioid; Cross-Over Studies; Humans; Long-Term Care; Low Back Pain; Pain Measurement; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 25503883
DOI: 10.1007/s00482-014-1449-8 -
Schmerz (Berlin, Germany) Feb 2015The efficacy and safety of long-term (≥ 6 months) opioid therapy (LtOT) in chronic noncancer pain (CNCP) is under debate. A systematic review with meta-analysis of... (Comparative Study)
Comparative Study Meta-Analysis Review
[Long-term opioid therapy in chronic noncancer pain. A systematic review and meta-analysis of efficacy, tolerability and safety in open-label extension trials with study duration of at least 26 weeks].
BACKGROUND
The efficacy and safety of long-term (≥ 6 months) opioid therapy (LtOT) in chronic noncancer pain (CNCP) is under debate. A systematic review with meta-analysis of the efficacy and harms of opioids in open-label extension studies of randomized controlled trials (RCTs) has not been conducted until now.
METHODS
We screened MEDLINE and clinicaltrials.gov (through to December 2013), as well as reference sections of systematic reviews of long-term RCTs of opioids in CNCP. We included open-label extension trials with a study duration ≥ 26 weeks of RCTs of ≥ 2 weeks duration. Using a random effects model, pooled estimates of event rates for categorical data and standardized mean differences (SMD) for continuous variables were calculated.
RESULTS
We included 11 open-label extension studies with 2445 participants with nociceptive (low back, osteoarthritis) and neuropathic (radicular, polyneuropathy) pain. Median study duration was 26 (range 26-108) weeks. Four studies tested oxycodone, two studies tramadol and buprenorphine; hydromorphone, morphine, oxymorphone and tapentadol were each tested in one study. Of the patients randomized at baseline, 28.5 % (95 % confidence interval, CI, 17.9-39.2 %) finished the open-label period; 53.5 % (95 % CI 38.1-68.2 %) of patients entering the open-label period finished the open-label period. In sum, the total loss was 71.5 % (95 % CI 60.9-83.1 %) of all patients primarily included into the RCT. A total of 4.9 % (95 % CI 2.9-8.2 %) of patients dropped out due lack of efficacy; 16.8 % (95 % CI 11.0-24.8 %) dropped out to due adverse events (AE) in the open-label period and 0.08 % (95 % CI 0.001-0.05 %) of patients died during the open-label period. Only one study systematically assessed aberrant drug behavior of the patients: 5.7 % (95 % CI 3.4-9.6 %) showed aberrant drug behavior in the opinion of the investigators and 2.6 % (95 % CI 1.2-5.8 %) were judged to show aberrant drug behavior by independent expert assessment. There was no significant change (p = 0.50) in pain intensity between the end of the randomized period and the end of open-label phase (SMD 0.19 [- 0.03, 0.41]; six studies with 1360 participants).
CONCLUSION
Only a minority of patients selected for opioid therapy at randomization finished the long-term open-label study. However, sustained effects of pain reduction could be demonstrated in these patients. LtOT can be considered in carefully selected and monitored CNCP patients who experience clinically meaningful pain reduction with at least tolerable AE in short-term opioid therapy. The English full-text version of this article is freely available at SpringerLink (under "Supplementary Material").
Topics: Analgesics, Opioid; Buprenorphine; Chronic Pain; Hydromorphone; Long-Term Care; Morphine; Oxycodone; Oxymorphone; Pain Measurement; Phenols; Randomized Controlled Trials as Topic; Tapentadol; Tramadol; Treatment Outcome
PubMed: 25503691
DOI: 10.1007/s00482-014-1452-0 -
Schmerz (Berlin, Germany) Feb 2015The efficacy, tolerability and safety of opioid therapy in chronic osteoarthritis (OA) pain is under debate. We updated a Cochrane systematic review on the efficacy and... (Comparative Study)
Comparative Study Review
[Opioids in chronic osteoarthritis pain. A systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks duration].
BACKGROUND
The efficacy, tolerability and safety of opioid therapy in chronic osteoarthritis (OA) pain is under debate. We updated a Cochrane systematic review on the efficacy and safety of opioids in chronic OA pain published in 2009.
METHODS
We screened MEDLINE, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL) up until October 2013, as well as reference sections of original studies and systematic reviews of randomized controlled trials (RCTs) of opioids in chronic osteoarthritis (OA) pain. We included double-blind randomized placebo-controlled studies lasting ≥ 4 weeks. Using a random effects model, absolute risk differences (RD) were calculated for categorical data and standardized mean differences (SMD) for continuous variables.
RESULTS
We included 20 RCTs with 33 treatment arms and 8545 participants. Median study duration was 12 (4-24) weeks. Oxycodone and tramadol were each tested in six studies; buprenorphine, hydromorphone, morphine and tapentadol each in two studies and codeine, fentanyl and oxymorphone in one study each. Results are reported with 95 % confidence intervals (CIs). Opioids were superior to placebo in reducing pain intensity (SMD - 0.22 [- 0.28, - 0.17], p < 0.00001; 16 studies with 6743 participants). Opioids were not superior to placebo in 50 % pain reduction (RD - 0.00 [- 0.07, 0.07], p = 0.96; two studies with 2684 participants). Opioids were superior to placebo in terms of reports of much or very much global improvement (RD 0.13 [0.05, 0.21], p = 0.002; three studies with 2251 participants). Opioids were superior to placebo in improving physical functioning (SMD - 0.22 [- 0.28, - 0.17], p < 0.00001; 14 studies with 5887 participants). Patients dropped out more frequently with opioids than with placebo (RD 0.17 [0.14, 0.21], p < 0.00001; 15 studies with 6834 participants; number needed to harm 5 [4-6]. There was no significant difference between opioids and placebo in the frequency of serious adverse events (SAE) or deaths over the respective observation periods.
CONCLUSION
Opioids were superior to placebo in terms of efficacy and inferior in terms of tolerability. The effect sizes of average reduction in pain intensity and physical disability were small. Opioids and placebo did not differ in terms of safety. The conclusion on the safety of opioids compared to placebo is limited by the low number of SAE and deaths. Short-term opioid therapy may be considered in selected chronic OA pain patients. No current evidence-based guideline recommends opioids as first-line treatment option for chronic OA pain. To provide superior evidence for future treatment guidelines, RCTs must directly compare existing pharmacological and nonpharmacological therapies and administer these in various combinations and sequences. The English full-text version of this article is freely available at SpringerLink (under "Supplemental").
Topics: Adult; Analgesics, Opioid; Chronic Pain; Double-Blind Method; Evidence-Based Medicine; Humans; Long-Term Care; Osteoarthritis; Pain Measurement; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 25376547
DOI: 10.1007/s00482-014-1451-1 -
Schmerz (Berlin, Germany) Feb 2015We updated a systematic review on the comparative efficacy, tolerability and safety of opioids and of their routes of application in chronic noncancer pain (CNCP). (Comparative Study)
Comparative Study Meta-Analysis Review
[Opioids in chronic noncancer pain-are opioids different? A systematic review and meta-analysis of efficacy, tolerability and safety in randomized head-to-head comparisons of opioids of at least four week's duration].
BACKGROUND
We updated a systematic review on the comparative efficacy, tolerability and safety of opioids and of their routes of application in chronic noncancer pain (CNCP).
METHODS
We screened MEDLINE, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL) up until October 2013, as well as the reference sections of original studies and systematic reviews of randomized controlled trials (RCTs) of opioids in CNCP. We included randomized head-to-head comparisons of opioids (opioid of the sponsor of the study versus standard opioid) of at least 4 week's duration. Using a random effects model, absolute risk differences (RD) were calculated for categorical data and standardized mean differences (SMD) for continuous variables. The quality of evidence was rated by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach.
RESULTS
We included 13 RCTs with 6748 participants. Median study duration was 15 weeks (range 4-56 weeks). Hydromorphone, morphine, oxymorphone and tapentadol were compared to oxycodone; fentanyl to morphine and buprenorphine to tramadol. In pooled analysis, there were no significant differences between the two groups of opioids in terms of mean pain reduction (low-quality evidence), the patient global impression to be much or very much improved outcome (low-quality evidence), physical function (very low-quality evidence), serious adverse events (moderate-quality evidence) or mortality (moderate-quality evidence). There was no significant difference between transdermal and oral application of opioids in terms of mean pain reduction, physical function, serious adverse events, mortality (all low-quality evidence) or dropout due to adverse events (very low-quality).
CONCLUSION
Pooled head-to-head comparisons of opioids (opioid of the sponsor of the study versus standard opioid) provide no rational for preferring one opioid and/or administration route over another in the therapy of patients with CNCP. The English full-text version of this article is freely available at SpringerLink (under "Supplemental").
Topics: Administration, Cutaneous; Administration, Oral; Analgesics, Opioid; Chronic Pain; Data Accuracy; Evidence-Based Medicine; Humans; Long-Term Care; Randomized Controlled Trials as Topic
PubMed: 25376545
DOI: 10.1007/s00482-014-1432-4 -
The Cochrane Database of Systematic... Sep 2014Osteoarthritis 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... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
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.
OBJECTIVES
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.
SEARCH METHODS
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.
SELECTION CRITERIA
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.
DATA COLLECTION AND ANALYSIS
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.
MAIN RESULTS
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).
AUTHORS' CONCLUSIONS
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.
Topics: Administration, Cutaneous; Administration, Oral; Analgesics, Opioid; Humans; Osteoarthritis, Hip; Osteoarthritis, Knee; Pain Measurement; Randomized Controlled Trials as Topic
PubMed: 25229835
DOI: 10.1002/14651858.CD003115.pub4 -
Pain Practice : the Official Journal of... Nov 2014A large percentage of patients with chronic pain on around-the-clock (ATC) opioids may experience increased pain occurring at the end of a scheduled dose, also known as... (Review)
Review
A large percentage of patients with chronic pain on around-the-clock (ATC) opioids may experience increased pain occurring at the end of a scheduled dose, also known as end-of-dose pain. Despite the significant prevalence and impact of end-of-dose pain in patients using extended-release (ER) opioids, there are no detailed analyses examining how the frequency of end-of-dose pain is linked to the formulations of long-acting opioids. Consequently, we performed a systematic review to evaluate how many published studies on patients with chronic cancer or noncancer pain identified end-of-dose pain. As only a few studies mentioned end-of-dose pain explicitly, we used breakthrough pain (BTP) as a surrogate parameter. We determined if any opioid formulation had a greater association with the frequency of BTP, the use of rescue medication for BTP, and the frequency of end-of-dose pain. Of the 39 studies entered in the final analysis, 14 studies across different formulations showed that ER opioids were effective in the prevention of BTP. The opioids most frequently studied were hydromorphone (26%), followed by morphine (23%), and transdermal buprenorphine (23%). Only 5% of the studies used immediate-release preparations. Overall, most studies showed that patients using ER preparations experienced fewer episodes of BTP compared with patients on placebo or an active comparator. This could reflect the favorable duration of action of these opioids compared with short-acting formulations. Future studies should examine the incidence of end-of-dose pain and use of rescue medicine in a longitudinal manner in patients with chronic pain taking short- vs. long-acting ATC opioids.
Topics: Analgesics, Opioid; Breakthrough Pain; Chronic Pain; Humans; Pain Measurement; Time; Treatment Outcome
PubMed: 24373184
DOI: 10.1111/papr.12156 -
The Cochrane Database of Systematic... Aug 2013The use of opioids in the long-term management of chronic low-back pain (CLBP) has increased dramatically. Despite this trend, the benefits and risks of these... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The use of opioids in the long-term management of chronic low-back pain (CLBP) has increased dramatically. Despite this trend, the benefits and risks of these medications remain unclear. This review is an update of a Cochrane review first published in 2007.
OBJECTIVES
To determine the efficacy of opioids in adults with CLBP.
SEARCH METHODS
We electronically searched the Cochrane Back Review Group's Specialized Register, CENTRAL, CINAHL and PsycINFO, MEDLINE, and EMBASE from January 2006 to October 2012. We checked the reference lists of these trials and other relevant systematic reviews for potential trials for inclusion.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) that assessed the use of opioids (as monotherapy or in combination with other therapies) in adults with CLBP that were at least four weeks in duration. We included trials that compared non-injectable opioids to placebo or other treatments. We excluded trials that compared different opioids only.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed the risk of bias and extracted data onto a pre-designed form. We pooled results using Review Manager (RevMan) 5.2. We reported on pain and function outcomes using standardized mean difference (SMD) or risk ratios with 95% confidence intervals (95% CI). We used absolute risk difference (RD) with 95% CI to report adverse effects.
MAIN RESULTS
We included 15 trials (5540 participants). Tramadol was examined in five trials (1378 participants); it was found to be better than placebo for pain (SMD -0.55, 95% CI -0.66 to -0.44; low quality evidence) and function (SMD -0.18, 95% CI -0.29 to -0.07; moderate quality evidence). Transdermal buprenorphine (two trials, 653 participants) may make little difference for pain (SMD -2.47, 95%CI -2.69 to -2.25; very low quality evidence), but no difference compared to placebo for function (SMD -0.14, 95%CI -0.53 to 0.25; very low quality evidence). Strong opioids (morphine, hydromorphone, oxycodone, oxymorphone, and tapentadol), examined in six trials (1887 participants), were better than placebo for pain (SMD -0.43, 95%CI -0.52 to -0.33; moderate quality evidence) and function (SMD -0.26, 95% CI -0.37 to -0.15; moderate quality evidence). One trial (1583 participants) demonstrated that tramadol may make little difference compared to celecoxib (RR 0.82, 95% CI 0.76 to 0.90; very low quality evidence) for pain relief. Two trials (272 participants) found no difference between opioids and antidepressants for either pain (SMD 0.21, 95% CI -0.03 to 0.45; very low quality evidence), or function (SMD -0.11, 95% -0.63 to 0.42; very low quality evidence). The included trials in this review had high drop-out rates, were of short duration, and had limited interpretability of functional improvement. They did not report any serious adverse effects, risks (addiction or overdose), or complications (sleep apnea, opioid-induced hyperalgesia, hypogonadism). In general, the effect sizes were medium for pain and small for function.
AUTHORS' CONCLUSIONS
There is some evidence (very low to moderate quality) for short-term efficacy (for both pain and function) of opioids to treat CLBP compared to placebo. The very few trials that compared opioids to non-steroidal anti-inflammatory drugs (NSAIDs) or antidepressants did not show any differences regarding pain and function. The initiation of a trial of opioids for long-term management should be done with extreme caution, especially after a comprehensive assessment of potential risks. There are no placebo-RCTs supporting the effectiveness and safety of long-term opioid therapy for treatment of CLBP.
Topics: Adult; Analgesics, Opioid; Anti-Inflammatory Agents, Non-Steroidal; Chronic Pain; Female; Humans; Low Back Pain; Male; Middle Aged; Randomized Controlled Trials as Topic
PubMed: 23983011
DOI: 10.1002/14651858.CD004959.pub4