Moderators of treatment effect of non-steroidal anti-inflammatory drugs for patients with (sub) acute low back pain: Protocol for a systematic review with individual participant data meta-analysis

A Cochrane review found that non-steroidal anti-inflammatory drugs (NSAIDs) are slightly more effective than placebo on acute and subacute low back pain (LBP) outcomes (pain intensity, disability, and global improvement). Our objectives are: (1) to assess the overall treatment effect of NSAIDs in adults with acute and subacute LBP; (2) to identify the moderation of baseline patients' characteristics on treatment effect. We will conduct a systematic search of RCTs on effectiveness of NSAIDs compared with placebo in adults with non-chronic LBP in Medline ALL, Embase, Cochrane Central Register of Controlled Trials*. We will screen the records after January 2020, and include eligible RCTs before January 2020 screened by the Cochrane review mentioned above. Our primary outcomes are pain intensity, disability, and health-related quality of life, secondary outcomes are adverse events. Our IPD dataset will consist of the information on each eligible trial characteristics and included variables according to a predefined coding scheme. We will assess risk-of-bias of included RCTs with the Cochrane Risk Of Bias (RoB)-2 assessment tool. We will perform power calculations with closed-form solutions and prioritize a one-stage approach for IPD-MA. For reporting the results, we will adhere to the PRISMA-IPD statement.

Opioid analgesics for nociceptive cancer pain: A comprehensive review

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.

Opioids for Acute Musculoskeletal Pain: A Systematic Review with Meta-Analysis

OBJECTIVE

To evaluate the efficacy of opioids for people with acute musculoskeletal pain against placebo.

STUDY DESIGN

Systematic review and meta-analyses of randomised, placebo-controlled trials of opioid analgesics for acute musculoskeletal pain in any setting. The primary outcomes were pain and disability at the immediate timepoint (< 24 h).

DATA SOURCES

Multiple databases were searched from their inception to February 22nd, 2023.

DATA SYNTHESIS

Continuous outcomes were converted to a 0-100 scale. Dichotomous outcomes were presented as risk differences. Risk of bias and certainty of evidence was assessed.

RESULTS

We located 17 trials (1 intravenous and 16 oral route of administration). For adults, high certainty evidence from 11 comparisons shows that oral opioids provide small benefits relative to placebo in the immediate term for pain (mean difference [MD] - 8.8 95% confidence interval [CI] - 12.0 to - 5.6). For disability, the difference is uncertain (MD - 6.2, 95% CI - 17.8 to 5.4). Opioid groups were at higher risk of adverse events (MD 14.3%, 95% CI 8.3-20.4%, very low certainty). There was moderate certainty evidence of a large effect of IV morphine on sciatica pain (MD -42.5, 95% CI - 49.9 to - 35.1, n = 197, 1 study). In paediatric populations, moderate certainty evidence from 3 trials shows that oral opioids probably do not provide benefit beyond that of placebo for pain (MD 6.1, 95% CI - 1.7 to 12.8) and there was no evidence for disability. There was low certainty evidence that there may be no difference in adverse events (MD 10.4%, 95% CI - 0.6 to 21.4%).

DISCUSSION

Intravenous morphine likely offers benefits, but oral opioids may not provide clinically meaningful benefits.

PROSPERO REGISTRATION

CRD42021249346.

Understanding general practitioners' prescribing choices to patients with chronic low back pain: a discrete choice experiment

BACKGROUND

Although NSAIDs are recommended as a first line analgesic treatment, opioids are very commonly prescribed to patients with low back pain (LBP) despite risks of harms.

AIM

This study aimed to determine factors contributing to general practitioners' (GPs') prescribing choices to patients with chronic LBP in a primary care setting.

METHOD

This discrete choice experiment (DCE) presented 210 GPs with hypothetical scenarios of a patient with chronic LBP. Participants chose their preferred treatment for each choice set, either the opioid, NSAID or neither. The scenarios varied by two patient attributes; non-specific LBP or LBP with referred leg pain (sciatica) and number of comorbidities. The three treatment attributes also varied, being: the type of opioid or NSAID, degree of pain reduction and number of adverse events. The significance of each attribute in influencing clinical decisions was the primary outcome and the degree to which GPs preferred the alternative based on the number of adverse events or the amount of pain reduction was the secondary outcome.

RESULTS

Overall, GPs preferred NSAIDs (45.2%, 95% CI 38.7-51.7%) over opioids (28.8%, 95% CI 23.0-34.7%), however there was no difference between the type of NSAID or opioid preferred. Additionally, the attributes of pain reduction and adverse events did not influence a GP's choice between NSAIDs or opioids for patients with chronic LBP.

CONCLUSION

GPs prefer prescribing NSAIDs over opioids for a patient with chronic low back pain regardless of patient factors of comorbidities or the presence of leg pain (i.e. sciatica).

Content and sentiment analysis of gabapentinoid-related tweets: An infodemiology study

INTRODUCTION

The increasing number of gabapentinoid (pregabalin and gabapentin) harms, including deaths observed across countries is concerning to health-care professionals and policy makers. However, it is unclear if the public shares these concerns. This study aimed to describe posts related to gabapentinoids, conduct a content analysis to identify common themes and describe adverse events or symptoms.

METHODS

Keywords of 'pregabalin' or 'Lyrica' or 'gabapentin' or 'Neurontin' were used to search for related tweets posted by people in the community between 8 March and 7 May 2021. Eligible tweets included a keyword in the post. We extracted de-identified data which included descriptive data of the total number of posts over time; and data on individual tweets including date, number of re-tweets and post content. Data were exported separately for pregabalin- and gabapentin-related tweets. A 20% random sample was used for the thematic analysis.

RESULTS

There were 2931 pregabalin-related tweets and 2736 gabapentin-related tweets. Thematic analysis revealed three themes (sharing positive experiences and benefits of taking gabapentinoids, people voicing their negative experiences, and people seeking opinions and sharing information). Positive experiences of gabapentinoids were related to sharing stories and giving advice. This was contrasted to negative experiences including ineffectiveness, withdrawals, side effects and frustration related to cost and insurance coverage. Brain fog was the most common adverse symptom reported. Gabapentinoid-related deaths were only mentioned in three tweets.

DISCUSSION

The increasing public health concern of gabapentinoid-related deaths was not translated to Twitter discussions.

Clinical Observation, Management and Function Of low back pain Relief Therapies (COMFORT): A cluster randomised controlled trial protocol

INTRODUCTION

Low back pain (LBP) is commonly treated with opioid analgesics despite evidence that these medicines provide minimal or no benefit for LBP and have an established profile of harms. International guidelines discourage or urge caution with the use of opioids for back pain; however, doctors and patients lack practical strategies to help them implement the guidelines. This trial will evaluate a multifaceted intervention to support general practitioners (GPs) and their patients with LBP implement the recommendations in the latest opioid prescribing guidelines.

METHODS AND ANALYSIS

This is a cluster randomised controlled trial that will evaluate the effect of educational outreach visits to GPs promoting opioid stewardship alongside non-pharmacological interventions including heat wrap and patient education about the possible harms and benefits of opioids, on GP prescribing of opioids medicines dispensed. At least 40 general practices will be randomised in a 1:1 ratio to either the intervention or control (no outreach visits; GP provides usual care). A total of 410 patient-participants (205 in each arm) who have been prescribed an opioid for LBP will be enrolled via participating general practices. Follow-up of patient-participants will occur over a 1-year period. The primary outcome will be the cumulative dose of opioid dispensed that was prescribed by study GPs over 1 year from the enrolment visit (in morphine milligram equivalent dose). Secondary outcomes include prescription of opioid medicines, benzodiazepines, gabapentinoids, non-steroidal anti-inflammatory drugs by study GPs or any GP, health services utilisation and patient-reported outcomes such as pain, quality of life and adverse events. Analysis will be by intention to treat, with a health economics analysis also planned.

ETHICS AND DISSEMINATION

The trial received ethics approval from The University of Sydney Human Research Ethics Committee (2022/511). The results will be disseminated via publications in journals, media and conference presentations.

TRIAL REGISTRATION NUMBER

ACTRN12622001505796.

Continued Opioid Use and Adverse Events Following Provision of Opioids for Musculoskeletal Pain in the Emergency Department: A Systematic Review and Meta-Analysis

BACKGROUND

The prevalence of continued opioid use or serious adverse events (SAEs) following opioid therapy in the emergency department (ED) for musculoskeletal pain is unclear. The aim of this review was to examine the prevalence of continued opioid use and serious adverse events (SAEs) following the provision of opioids for musculoskeletal pain in the emergency department (ED) or at discharge.

METHODS

Records were searched from MEDLINE, EMBASE and CINAHL from inception to 7 October 2022. We included randomised controlled trials and observational studies enrolling adult patients with musculoskeletal pain who were administered and/or prescribed opioids in the ED. Continued opioid use and opioid misuse data after day 4 since ED discharge were extracted. Adverse events were coded using the Common Terminology Criteria for Adverse Events (CTCAE), and those rated as grades 3-4 (severe or life-threatening) and grade 5 (death) were considered SAEs. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool.

RESULTS

Seventy-two studies were included. Among opioid-naïve patients who received an opioid prescription, 6.8-7.0% reported recent opioid use at 3-12 months after discharge, 4.4% filled ≥ 5 opioid prescriptions and 3.1% filled > 90-day supply of opioids within 6 months. The prevalence of SAEs was 0.02% [95% confidence interval (CI) 0, 0.2%] in the ED and 0.1% (95% CI 0, 1.5%) within 2 days. One study observed 42.9% of patients misused opioids within 30 days after discharge.

CONCLUSIONS

Around 7% of opioid-naïve patients with musculoskeletal pain receiving opioid therapy continue opioid use at 3-12 months after ED discharge. SAEs following ED administration of an opioid were uncommon; however, studies only monitored patients for 2 days.

PROTOCOL REGISTRATION

10.31219/osf.io/w4z3u.

Prevalence of Nonsteroidal Antiinflammatory Drugs Prescribed for Osteoarthritis: A Systematic Review and Meta-Analysis of Observational Studies

OBJECTIVE

Our systematic review aimed to investigate the proportion of participants with osteoarthritis who were prescribed nonsteroidal antiinflammatory drugs (NSAIDs) by their health care provider.

METHODS

Electronic databases were searched for observational studies reporting NSAID prescribing to participants with diagnosed osteoarthritis of any region. Risk of bias was assessed using a tool designed for observational studies measuring prevalence. Random and fixed-effects meta-analysis was used. Meta-regression investigated study-level factors associated with prescribing. The overall evidence quality was assessed using Grading of Recommendations Assessment, Development, and Evaluation criteria.

RESULTS

Fifty-one studies were included, published between 1989 and 2022, with 6,494,509 participants. The mean age of participants was 64.7 years (95% confidence interval [95% CI] 62.4, 67.0; n = 34 studies). Most studies were from Europe and Central Asia (n = 23 studies), and North America (n = 12 studies). Most studies were judged to be at low risk of bias (75%). Heterogeneity was eliminated when removing studies with a high risk of bias, to give a pooled estimate of NSAIDs prescribing to participants with osteoarthritis of 43.8% (95% CI 36.8, 51.1; moderate quality of evidence). Meta-regression determined that prescribing was associated with year (decreased prescribing over time; P = 0.05) and geographic region (P = 0.03; higher in Europe and Central Asia and in South Asia than in North America) but not with clinical setting.

CONCLUSION

Data from over 6.4 million participants with osteoarthritis between 1989 and 2022 indicate that NSAID prescribing has decreased over time and that prescribing differs between geographic locations.

General practitioners' decision-making process to prescribe pain medicines for low back pain: a qualitative study

BACKGROUND

Pain medicines are widely prescribed by general practitioners (GPs) when managing people with low back pain (LBP), but little is known about what drives decisions to prescribe these medicines.

OBJECTIVES

The aim of this study was to investigate what influences GPs' decision to prescribe pain medicines for LBP.

DESIGN

Qualitative study with in-depth interviews.

SETTING

Australian primary care.

PARTICIPANTS

We interviewed 25 GPs practising in Australia experienced in managing LBP (mean (SD) age 53.4 (9.1) years, mean (SD) years of experience: 24.6 (9.3), 36% female). GPs were provided three vignettes describing common LBP presentations (acute exacerbation of chronic LBP, subacute sciatica and chronic LBP) and were asked to think aloud how they would manage the cases described in the vignettes.

DATA ANALYSIS

We summarised GP's choices of pain medicines for each vignette using content analysis and used framework analysis to investigate factors that affected GP's decision-making.

RESULTS

GPs more commonly prescribed opioid analgesics. Anticonvulsants and antidepressants were also commonly prescribed depending on the presentation described in the vignette. GP participants made decisions about what pain medicines to prescribe for LBP largely based on previous experiences, including their own personal experiences of LBP, rather than guidelines. The choice of pain medicine was influenced by a range of clinical factors, more commonly the patient's pathoanatomical diagnosis. While many adhered to principles of judicious use of pain medicines, polypharmacy scenarios were also common. Concerns about drug-seeking behaviour, adverse effects, stigma around opioid analgesics and pressure from regulators also shaped their decision-making process.

CONCLUSIONS

We identified several aspects of decision-making that help explain the current profile of pain medicines prescribed for LBP by GPs. Themes identified by our study could inform future implementation strategies to improve the quality use of medicines for LBP.

Deprescribing interventions for gabapentinoids in adults: A scoping review

The emerging issue of rising gabapentinoid misuse is being recognized alongside the lack of current evidence supporting the safe and effective deprescribing of gabapentinoids. This scoping review aimed to assess the extent and nature of gabapentinoid deprescribing interventions in adults, either in reducing dosages, or prescribing of, gabapentinoids. Electronic databases were searched on 23 February 2022 without restrictions. Eligible studies included randomized, non-randomized and observational studies that assessed an intervention aimed at reducing/ceasing the prescription/use of a gabapentinoid in adults for any indication in a clinical setting. The research outcomes investigated the type of intervention, prescribing rates, cessations, patient outcomes and adverse events. Extracted outcome data were categorized as either short (≤3 months), intermediate (>3 but <12 months) or long (≥12 months) term. A narrative synthesis was conducted. The four included studies were conducted in primary and acute care settings. Interventions were of dose-reducing protocols, education and/or pharmacological-based approaches. In the randomized trials, gabapentinoid use could be ceased in at least one third of participants. In the two observational trials, gabapentinoid prescribing rates decreased by 9%. Serious adverse events and adverse events specifically related to gabapentinoids were reported in one trial. No study included patient-focused psychological interventions in the deprescribing process, nor provided any long-term follow-up. This review highlights the lack of existing evidence in this area. Due to limited available data, our review was unable to make any firm judgements on the most effective gabapentinoid deprescribing interventions in adults, highlighting the need for more research in this area.

A Second Look at the Risks of Serious Adverse Events with Orthopaedic Manual Therapy, Paracetamol, and NSAID Treatment of Neck Pain

Letter to the Editor-in-Chief in response to JOSPT article "International Framework for Examination of the Cervical Region for Potential of Vascular Pathologies of the Neck Prior to Musculoskeletal Intervention: International IFOMPT Cervical Framework" by Rushton A, Carlesso LC, Flynn T, et al. J Orthop Sports Phys Ther 2023;53(6):1-2. doi:10.2519/jospt.2023.0202.

Surgical versus non-surgical treatment for sciatica: systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To investigate the effectiveness and safety of surgery compared with non-surgical treatment for sciatica.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, CINAHL, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the World Health Organisation International Clinical Trials Registry Platform from database inception to June 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials comparing any surgical treatment with non-surgical treatment, epidural steroid injections, or placebo or sham surgery, in people with sciatica of any duration due to lumbar disc herniation (diagnosed by radiological imaging).

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data. Leg pain and disability were the primary outcomes. Adverse events, back pain, quality of life, and satisfaction with treatment were the secondary outcomes. Pain and disability scores were converted to a scale of 0 (no pain or disability) to 100 (worst pain or disability). Data were pooled using a random effects model. Risk of bias was assessed with the Cochrane Collaboration's tool and certainty of evidence with the grading of recommendations assessment, development, and evaluation (GRADE) framework. Follow-up times were into immediate term (≤six weeks), short term (>six weeks and ≤three months), medium term (>three and <12 months), and long term (at 12 months).

RESULTS

24 trials were included, half of these investigated the effectiveness of discectomy compared with non-surgical treatment or epidural steroid injections (1711 participants). Very low to low certainty evidence showed that discectomy, compared with non-surgical treatment, reduced leg pain: the effect size was moderate at immediate term (mean difference -12.1 (95% confidence interval -23.6 to -0.5)) and short term (-11.7 (-18.6 to -4.7)), and small at medium term (-6.5 (-11.0 to -2.1)). Negligible effects were noted at long term (-2.3 (-4.5 to -0.2)). For disability, small, negligible, or no effects were found. A similar effect on leg pain was found when comparing discectomy with epidural steroid injections. For disability, a moderate effect was found at short term, but no effect was observed at medium and long term. The risk of any adverse events was similar between discectomy and non-surgical treatment (risk ratio 1.34 (95% confidence interval 0.91 to 1.98)).

CONCLUSION

Very low to low certainty evidence suggests that discectomy was superior to non-surgical treatment or epidural steroid injections in reducing leg pain and disability in people with sciatica with a surgical indication, but the benefits declined over time. Discectomy might be an option for people with sciatica who feel that the rapid relief offered by discectomy outweighs the risks and costs associated with surgery.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021269997.

Effectiveness of Opioid Analgesic Medicines Prescribed in or at Discharge From Emergency Departments for Musculoskeletal Pain : A Systematic Review and Meta-analysis

BACKGROUND

The comparative benefits and harms of opioids for musculoskeletal pain in the emergency department (ED) are uncertain.

PURPOSE

To evaluate the comparative effectiveness and harms of opioids for musculoskeletal pain in the ED setting.

DATA SOURCES

Electronic databases and registries from inception to 7 February 2022.

STUDY SELECTION

Randomized controlled trials of any opioid analgesic compared with placebo or a nonopioid analgesic administered or prescribed to adults in or on discharge from the ED.

DATA EXTRACTION

Pain and disability were rated on a scale of 0 to 100 and pooled using a random-effects model. Certainty of evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework.

DATA SYNTHESIS

Forty-two articles were included (n = 6128). In the ED, opioids were statistically but not clinically more effective in reducing pain in the short term (about 2 hours) than placebo and paracetamol (acetaminophen) but were not clinically or statistically more effective than nonsteroidal anti-inflammatory drugs (NSAIDs) or local or systemic anesthetics. Opioids may carry higher risk for harms than placebo, paracetamol, or NSAIDs, although evidence is very uncertain. There was no evidence of difference in harms associated with local or systemic anesthetics.

LIMITATIONS

Low or very low GRADE ratings for some outcomes, unexplained heterogeneity, and little information on long-term outcomes.

CONCLUSION

The risk-benefit balance of opioids versus placebo, paracetamol, NSAIDs, and local or systemic anesthetics is uncertain. Opioids may have equivalent pain outcomes compared with NSAIDs, but evidence on comparisons of harms is very uncertain and heterogeneous. Although factors such as route of administration or dosage may explain some heterogeneity, more work is needed to identify which subgroups will have a more favorable benefit-risk balance for one analgesic over another. Longer-term pain management once dose thresholds are reached is also uncertain.

PRIMARY FUNDING SOURCE

None. (PROSPERO: CRD42021275293).

Spinal Cord Stimulators: An Analysis of the Adverse Events Reported to the Australian Therapeutic Goods Administration

BACKGROUND

Spinal cord stimulators are used to treat intractable pain. Placebo-controlled trials of spinal cord stimulators typically involve short-term treatment and follow-up, so long-term safety and efficacy are unclear.

AIM

The aim of the study was to describe the adverse events relating to spinal cord stimulators reported to the Therapeutic Goods Administration of Australia between July 2012 and January 2019.

METHODS

Adverse events were coded by seriousness, severity, body system affected, type of event, action taken, and attribution of fault. Data on the number of stimulators implanted and removed were sourced from the Admitted Patient Care Minimum Data Set.

RESULTS

Five hundred twenty adverse events were reported for spinal cord stimulators. Most events were rated as severe (79%) or life-threatening (13%). Device malfunction was the most common event (56.5%). The most common action taken in response to an adverse event was surgical intervention with or without antibiotics (80%). The ratio of removals to implants was 4 per every 10 implanted.

CONCLUSIONS

Spinal cords stimulators have the potential for serious harm, and each year in Australia, many are removed. In view of the low certainty evidence of their long-term safety and effectiveness, our results raise questions about their role in providing long-term management of intractable pain.

Continued opioid use following an emergency department presentation for low back pain

OBJECTIVE

To investigate the proportion of patients with low back pain who receive an opioid analgesic prescription on hospital discharge, the proportion using opioid analgesics 4 weeks after discharge, and to identify predictors of continued opioid analgesic use at 4 weeks after an ED presentation in opioid-naïve patients.

METHODS

An observational cohort study nested within a randomised controlled trial in four EDs in New South Wales, Australia. Participants were adults who presented to the ED with non-specific low back pain or low back pain with lower limb neurological signs and symptoms. Electronic medical records supplemented the patient-reported pain and use of opioid analgesics at 4-week follow up.

RESULTS

Of the 104 patients included, 33 (31.7%, 95% confidence interval [CI] 22.9-41.6) received an opioid analgesic prescription at hospital discharge and 38 (36.5%, 95% CI 27.3-46.6) reported taking an opioid analgesic for pain 4 weeks after the ED presentation. Among opioid-naïve patients (n = 85), older age (odds ratio [OR] 1.04, 95% CI 1.00-1.08, P = 0.031) was the only predictor for continued opioid analgesic use at 4 weeks post-ED presentation.

CONCLUSION

About one-third of patients who present to the ED with low back pain receive an opioid analgesic prescription on discharge and are taking an opioid analgesic 4 weeks later. These findings justify future research to identify strategies to reduce the risk of long-term opioid use in patients who present to the ED with low back pain.

Immunomodulatory effects of pharmaceutical opioids and antipyretic analgesics: Mechanisms and relevance to infection

Understanding how pharmaceutical opioids and antipyretic analgesics interact with the immune system potentially has major clinical implications for management of patients with infectious diseases and surgical and critical care patients. An electronic search was carried out on MEDLINE, EMBASE, PsycINFO, CENTRAL and the Cochrane library to identify reports describing the immunomodulatory effects of opioid analgesics and antipyretic analgesics, and their effects in infectious diseases. In adaptive immunity, nonsteroidal anti-inflammatory drugs have divergent effects: augmenting cell-mediated immunity but inhibiting humoral immunity. Nonsteroidal anti-inflammatory drugs have demonstrated a beneficial role in Mycobacterium tuberculosis infection and histoplasmosis in animals, and may be plausible adjuvants to antimicrobial agents in these diseases. There is a need to evaluate these findings rigorously in human clinical trials. There is preliminary evidence demonstrating antiviral effects of indomethacin in SARS CoV-2 in vitro; however, uncertainty regarding its clinical benefit in humans needs to be resolved in large clinical trials. Certain opioid analgesics are associated with immunosuppressive effects, with a developing understanding that fentanyl, morphine, methadone and buprenorphine suppress innate immunity, whilst having diverse effects on adaptive immunity. Morphine suppresses key cells of the innate immunity and is associated with greater risk of infection in the postsurgical setting. Efforts are needed to achieve adequate analgesia whilst avoiding suppression of the innate immunity in the immediate postoperative period caused by certain opioids, particularly in cancer surgery.

Advice and education provide small short-term improvements in pain and disability in people with non-specific spinal pain: a systematic review

QUESTIONS

What is the effect of advice/education compared with placebo or no advice/education on pain and disability in people with non-specific spinal pain? To what extent do characteristics of the patients, trial or intervention modify the estimate of the treatment effects?

DESIGN

A systematic review with meta-analyses of randomised controlled trials.

PARTICIPANTS

Adults with non-specific back and/or neck pain with or without radiating leg/arm pain of any duration were included. Trials recruiting pregnant women or surgical patients in the immediate postoperative phase were ineligible.

INTERVENTION

Advice or education.

OUTCOME MEASURES

The primary outcomes were self-reported pain and disability, and the secondary outcome was adverse events. The following potential effect modifiers were examined: risk of bias, duration of pain, location of pain, intensity of intervention and mode of intervention.

RESULTS

Twenty-seven trials involving 7,006 participants were included. Eighteen of the included trials were assessed as being at low risk of bias (≥ 6 on the PEDro scale). There was low-quality evidence that advice had a small effect on pain (MD -8.2, 95% CI -12.5 to -3.9, n = 2,241) and moderate-quality evidence that advice had a small effect on disability (MD -4.5, 95% CI -7.9 to -1.0, n = 2,579) compared with no advice or placebo advice in the short-term. None of the items that were assessed modified the treatment effects.

CONCLUSION

Advice provides short-term improvements in pain and disability in non-specific spinal pain, but the effects are small and may be insufficient as the sole treatment for patients with spinal pain.

REGISTRATION

PROSPERO CRD42020162008.

Systematic review with meta-analysis: The effects of non-steroidal anti-inflammatory drugs and anti-platelet therapy on the incidence and recurrence of hepatocellular carcinoma

BACKGROUND

Chemoprevention with NSAIDs, including aspirin, and anti-platelet therapy (APT), has been suggested to reduce the incidence and recurrence of hepatocellular carcinoma (HCC).

AIM

To determine by meta-analysis whether NSAIDs and APT use affected HCC incidence, HCC recurrence and liver-related mortality in at-risk populations with chronic liver disease.

METHOD

Electronic databases including Pubmed, Scopus, Medline, Embase and Cochrane Library were searched (from inception to 31 May 2021) for eligible studies evaluating the impacts of NSAID or APT use on HCC incidence, recurrence and mortality. Data on HCC incidence, recurrence, liver-related mortality or bleeding complications had to be available. Studies were included if they evaluated adults with hepatitis B virus (HBV), hepatitis C virus (HCV), alcohol-related liver disease (ALD) or nonalcoholic steatohepatitis that were administered at least one NSAID or APT for a defined period of time and were followed for at least 6 months. The primary outcome was HCC incidence. Secondary outcomes included: HCC recurrence, liver-related mortality and bleeding complications. Data were pooled using a random effects model with hazard ratios (HRs) or odds ratio (OR), and 95% confidence intervals (CIs) presented.

RESULTS

Of 3773 articles screened, 19 studies were included, with a total of 147 283 participants. Aspirin use reduced the risk of HCC incidence (HR: 0.51, 95% CI: 0.36-0.72); and improved liver-related mortality (OR: 0.32, 95% CI: 0.15-0.70), with a small increased risk of gastrointestinal bleeding events (OR: 1.32, 95% CI: 1.08-1.94). With respect to HCC recurrence following treatment, analysis of all aspirin and NSAID treatment (including; aspirin only; non-aspirin NSAIDs only; and combination NSAIDs groups) was associated with a decreased risk of HCC recurrence (HR: 0.80, 95% CI: 0.75-0.86). By stratified analysis, only the non-aspirin NSAID group showed significant risk reduction (HR: 0.73, 95% CI: 0.63-0.84).

CONCLUSION

The study supports the use of aspirin in at-risk individuals to reduce the incidence of HCC and liver-related mortality. HCC recurrence following treatment was lower with NSAID treatment.

The efficacy and safety of paracetamol for pain relief: an overview of systematic reviews

OBJECTIVE

To evaluate the efficacy and safety of paracetamol as an analgesic medication in a range of painful conditions.

STUDY DESIGN

Systematic review of systematic reviews of the analgesic effects of paracetamol in randomised, placebo-controlled trials. Conduct of systematic reviews was assessed with AMSTAR-2; confidence in effect estimates (quality of evidence) was assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria.

DATA SOURCES

MEDLINE, EMBASE, PsycINFO, Cochrane Database of Systematic Reviews; systematic reviews published 1 January 2010 - 30 April 2020.

DATA SYNTHESIS

We extracted pain and adverse events outcomes from 36 systematic reviews that assessed the efficacy of paracetamol in 44 painful conditions. Continuous pain outcomes were expressed as mean differences (MDs; standardised 0-10-point scale); dichotomous outcomes were expressed as risk ratios (RRs). There is high quality evidence that paracetamol provides modest pain relief for people with knee or hip osteoarthritis (MD, -0.3 points; 95% CI, -0.6 to -0.1 points) and after craniotomy (MD, -0.8 points; 95% CI, -1.4 to -0.2 points); there is moderate quality evidence for its efficacy in tension-type headache (pain-free at 2 hours: RR, 1.3; 95% CI, 1.1-1.4) and perineal pain soon after childbirth (patients experiencing 50% pain relief: RR, 2.4; 95% CI, 1.5-3.8). There is high quality evidence that paracetamol is not effective for relieving acute low back pain (MD, 0.2 points; 95% CI, -0.1 to 0.4 points). Evidence regarding efficacy in other conditions was of low or very low quality. Frequency of adverse events was generally similar for people receiving placebo or paracetamol, except that transient elevation of blood liver enzyme levels was more frequent during repeated administration of paracetamol to patients with spinal pain (RR, 3.8; 95% CI, 1.9-7.4).

CONCLUSIONS

For most conditions, evidence regarding the effectiveness of paracetamol is insufficient for drawing firm conclusions. Evidence for its efficacy in four conditions was moderate to strong, and there is strong evidence that paracetamol is not effective for reducing acute low back pain. Investigations that evaluate more typical dosing regimens are required.

PROSPERO REGISTRATION

CRD42015029282 (prospective).

OASIS-a randomised, placebo-controlled trial of oral glucocorticoids for leg pain in patients with acute sciatica: trial protocol

INTRODUCTION

Sciatica is a lower spine condition characterised by radiating leg pain below the knee. It may be accompanied by motor and sensory loss in the distribution of a spinal nerve. There are few effective treatments for sciatica. Orally administered glucocorticoids have shown some promise, however, any beneficial effects need to be confirmed and weighed against drug safety and cost-effectiveness, in a high-quality, definitive trial.

METHODS AND ANALYSIS

The Oral Steroids In Sciatica (OASIS) trial is a randomised, placebo-controlled, double-blind trial that will evaluate a tapering regimen of oral prednisolone in 200 participants with acute sciatica. Participants will be recruited on presentation to general practice, specialist outpatient clinics or hospital emergency departments and randomised to receive orally administered prednisolone 50 mg per day, up to 3 days then tapering to cessation over 10 days, or placebo, for a maximum of 13 days, in addition to guideline advice. Participants will be followed for 1 year. The primary endpoint will be leg pain intensity at 2 weeks. Secondary outcomes will include back pain intensity, disability, time to recovery, quality of life and treatment success rate. Adverse events will be assessed and a cost-effectiveness analysis will be conducted.

ETHICS AND DISSEMINATION

Ethical approval has been granted from the Human Research Ethics Committee, The University of Sydney. Trial results will be disseminated by publications and conference presentations and via the media.

TRIAL REGISTRATION NUMBER

ACTRN12619001716156.

An Electronic Clinical Decision Support System for the Management of Low Back Pain in Community Pharmacy: Development and Mixed Methods Feasibility Study

Background

People with low back pain (LBP) in the community often do not receive evidence-based advice and management. Community pharmacists can play an important role in supporting people with LBP as pharmacists are easily accessible to provide first-line care. However, previous research suggests that pharmacists may not consistently deliver advice that is concordant with guideline recommendations and may demonstrate difficulty determining which patients require prompt medical review. A clinical decision support system (CDSS) may enhance first-line care of LBP, but none exists to support the community pharmacist–client consultation.

Objective

This study aimed to develop a CDSS to guide first-line care of LBP in the community pharmacy setting and to evaluate the pharmacist-reported usability and acceptance of the prototype system.

Methods

A cross-platform Web app for the Apple iPad was developed in conjunction with academic and clinical experts using an iterative user-centered design process during interface design, clinical reasoning, program development, and evaluation. The CDSS was evaluated via one-to-one user-testing with 5 community pharmacists (5 case vignettes each). Data were collected via video recording, screen capture, survey instrument (system usability scale), and direct observation.

Results

Pharmacists’ agreement with CDSS-generated self-care recommendations was 90% (18/20), with medicines recommendations was 100% (25/25), and with referral advice was 88% (22/25; total 70 recommendations). Pharmacists expressed uncertainty when screening for serious pathology in 40% (10/25) of cases. Pharmacists requested more direction from the CDSS in relation to automated prompts for user input and page navigation. Overall system usability was rated as excellent (mean score 92/100, SD 6.5; 90th percentile compared with similar systems), with acceptance rated as good to excellent.

Conclusions

A novel CDSS (high-fidelity prototype) to enhance pharmacist care of LBP was developed, underpinned by clinical practice guidelines and informed by a multidisciplinary team of experts. User-testing revealed a high level of usability and acceptance of the prototype system, with suggestions to improve interface prompts and information delivery. The small study sample limits the generalizability of the findings but offers important insights to inform the next stage of system development.

Efficacy and harms of orally, intramuscularly or intravenously administered glucocorticoids for sciatica: A systematic review and meta-analysis

BACKGROUND

Sciatica can be a debilitating condition and there is limited guidance on the use of glucocorticoids administered via the oral, intramuscular or intravenous route for this condition. These represent viable treatment options in the primary care setting.

OBJECTIVE

To evaluate the evidence on efficacy and harms of oral, IM and IV glucocorticoid administration for sciatica.

DATABASES AND DATA TREATMENT

MEDLINE, EMBASE, CENTRAL, CINAHL, PsycINFO (inception to October 2018) were searched for randomised placebo-controlled trials evaluating oral, IV or IM glucocorticoid administration for sciatica. Two authors extracted outcomes data. Continuous pain and disability outcomes were converted to a 0 (no pain/disability) to 100 (worst pain/disability) scale. Data were pooled using a random effects model. Overall quality of evidence was assessed using GRADE. Primary outcomes were leg pain and disability. Primary follow-up period was the immediate-term (<2 weeks from administration). We also considered adverse events.

RESULTS

Nine trials were eligible. One study [n = 27] provided low quality evidence of a small reduction in disability with early administration of oral prednisone (within 1 week); MD -13.4 [-23.3, -3.5] but not for pain MD -2.5 [-16.9, 11.9]. There was low quality evidence from one study [n = 78] of moderate reduction in disability and small reduction in pain with early (within 72 hr of symptom onset) single intramuscular administration of methylprednisolone acetate; MD -24.5 [-38.8, -10.2] and -14.0 [-27.4, -0.6], respectively. There were no immediate-term benefits with IV administration.

CONCLUSION

The effects of glucocorticoids on immediate-term leg pain or disability are uncertain. Future large high quality trials are needed to resolve this uncertainty.

Is the use of metformin in patients undergoing dialysis hazardous for life? A systematic review of the safety of metformin in patients undergoing dialysis

AIMS

Metformin may have clinical benefits in dialysis patients; however, its safety in this population is unknown. This systematic review evaluated the safety of metformin in dialysis patients.

METHODS

MEDLINE, Embase, CENTRAL, PsycINFO and the Cochrane Library were searched for randomised controlled trials and observational studies evaluating metformin use in dialysis patients. Three authors reviewed the studies and extracted data. The primary outcomes were mortality, occurrence of lactic acidosis and myocardial infarction (MI) in patients taking metformin during dialysis treatment for ≥12 months (long term). Risk of bias was assessed using Risk Of Bias In Nonrandomised Studies of Interventions (ROBINS-1). Overall quality of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

Fifteen observational studies were eligible; 7 were prospective observational studies and 8 were case reports/case series. No randomised controlled trials were identified. The 7 prospective observational studies (n = 194) reported on cautious metformin use in patients undergoing maintenance dialysis. Only 3 provided long-term follow-up data. In 2 long-term studies of metformin therapy (≤1000 mg/d) in patients undergoing peritoneal dialysis (PD), 1 reported 6 deaths (6/83; 7%) due to major cardiovascular events (3 MI) and the other reported no deaths (0/35). One long-term study of metformin therapy (250 mg to 500 mg thrice weekly) in patients undergoing haemodialysis reported 4 deaths (4/61; 7%) due to major cardiovascular events (2 MI). These findings provide very low-quality evidence as they come from small observational studies.

CONCLUSION

The evidence regarding the safety of metformin in people undergoing dialysis is inconclusive. Appropriately designed randomised controlled trials are needed to resolve this uncertainty.

Management of low back pain in Australian emergency departments

Background

To describe the diagnoses of people who present to the emergency department (ED) with low back pain (LBP), the proportion of people with a lumbar spine condition who arrived by ambulance, received imaging, opioids and were admitted to hospital; and to explore factors associated with these four outcomes.

Methods

In this retrospective study, we analysed electronic medical records for all adults presenting with LBP at three Australian EDs from January 2016 to June 2018. Outcomes included discharge diagnoses and key aspects of care (ambulance transport, lumbar spine imaging, provision of opioids, admission). We explored factors associated with these care outcomes using multilevel mixed-effects logistic regression models and reported data as ORs.

Results

There were 14 024 presentations with a ‘visit reason’ for low back pain, of which 6393 (45.6%) had a diagnosis of a lumbar spine condition. Of these, 31.4% arrived by ambulance, 23.6% received lumbar imaging, 69.6% received opioids and 17.6% were admitted to hospital. Older patients (OR 1.79, 95% CI 1.56 to 2.04) were more likely to be imaged. Opioids were less used during working hours (OR 0.81, 95% CI 0.67 to 0.98) and in patients with non-serious LBP compared with patients with serious spinal pathology (OR 1.65, 95% CI 1.07 to 2.55). Hospital admission was more likely to occur during working hours (OR 1.74, 95% CI 1.48 to 2.05) and for those who arrived by ambulance (OR 2.98, 95% CI 2.53 to 3.51).

Conclusion

Many ED presentations of LBP were not due to a lumbar spine condition. Of those that were, we noted relatively high rates of lumbar imaging, opioid use and hospital admission.

Transcutaneous electric nerve stimulation (TENS) for acute low back pain: systematic review

Background and aims There has been no comprehensive evaluation of the efficacy of transcutaneous electric nerve stimulation (TENS) for acute low back pain (LBP). The aim of this systematic review was to investigate the efficacy and safety of TENS for acute LBP. Methods We searched MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, CINAHL and PsycINFO (inception to May 2018) for randomised placebo controlled trials. The primary outcome measure was pain relief in the immediate term (within 2-weeks of administration) assessed using the 100 mm visual analogue scale. A mean difference of at least 10 points on the 100-point pain scale was considered clinically significant. Methodological quality of the eligible studies was assessed using the PEDro scale and overall quality assessment rating was assessed using GRADE. Results Three placebo controlled studies (n = 192) were included. One low quality trial (n = 63) provides low quality evidence that ~30 min treatment with TENS in an emergency-care setting provides clinically worthwhile pain relief for moderate to severe acute LBP in the immediate term compared with sham TENS [Mean Difference (MD) - 28.0 (95% CI - 32.7, -23.3)]. Two other studies which administered a course of TENS over 4-5 weeks, in more usual settings provide inconclusive evidence; MD -2.75 (95% CI -11.63, 6.13). There was limited data on adverse events or long term follow-up. Conclusions The current evidence is insufficient to support or dismiss the use of TENS for acute LBP. Implications There is insufficient evidence to guide the use of TENS for acute LBP. There is low quality evidence of moderate improvements in pain with a short course of TENS (~30 min) during emergency transport of patients to the hospital. Future research should evaluate whether TENS has an opioid sparing role in the management of acute LBP.

Combination Therapy with an SGLT2 Inhibitor as Initial Treatment for Type 2 Diabetes: A Systematic Review and Meta-Analysis

Background: Guidelines differ with regard to indications for initial combination pharmacotherapy for type 2 diabetes. Aims: To compare the efficacy and safety of (i) sodium-glucose cotransporter 2 (SGLT2) inhibitor combination therapy in treatment-naïve type 2 diabetes adults; (ii) initial high and low dose SGLT2 inhibitor combination therapy. Methods: PubMed, Embase and Cochrane Library were searched for randomised controlled trials (RCTs) of initial SGLT2 combination therapy. Mean difference (MD) for changes from baseline (HbA1c, weight, blood pressure) after 24–26 weeks of treatment and relative risks (RR, safety) were calculated using a random-effects model. Risk of bias and quality of evidence was assessed. Results: In 4 RCTs (n = 3749) there was moderate quality evidence that SGLT2 inhibitor/metformin combination therapy resulted in a greater reduction in HbA1c (MD (95% CI); −0.55% (−0.67, −0.43)) and weight (−2.00 kg (−2.34, −1.66)) compared with metformin monotherapy, and a greater reduction in HbA1c (−0.59% (−0.72, −0.46)) and weight (−0.57 kg (−0.89, −0.25)) compared with SGLT2 inhibitor monotherapy. The high dose SGLT2 inhibitor/metformin combination resulted in a similar HbA1c but greater weight reduction; −0.47 kg (−0.88, −0.06) than the low dose combination therapy. The RR of genital infection with combination therapy was 2.22 (95% CI 1.33, 3.72) and 0.69 (95% CI 0.50, 0.96) compared with metformin and SGLT2 inhibitor monotherapy, respectively. The RR of diarrhoea was 2.23 (95% CI 1.46, 3.40) with combination therapy compared with SGLT2 inhibitor monotherapy. Conclusions: Initial SGLT2 inhibitor/metformin combination therapy has glycaemic and weight benefits compared with either agent alone and appears relatively safe. High dose SGLT2 inhibitor/metformin combination therapy appears to have modest weight, but no glycaemic benefits compared with the low dose combination therapy.

Clinicopathologic and Prognostic Significance of Programmed Cell Death Ligand 1 Expression in Patients with Non-Medullary Thyroid Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Evidence has shown that programmed cell death ligand 1 (PD-L1) overexpression is associated with poor prognosis and resistance to immune therapies in several human cancers. However, data on the prognostic significance of PD-L1 expression in thyroid cancer are limited and remain controversial. This systematic review and meta-analysis aimed to evaluate comprehensively the clinicopathologic significance and prognostic value of PD-L1 expression in non-medullary thyroid cancers.

METHODS

Electronic databases, including Medline/PubMed, EMBASE, and the Cochrane Library, were searched up until July 5, 2017. In total, seven comparisons (from six articles) comprising 1421 patients were included in the pooled analysis.

RESULTS

There was moderate quality evidence from four studies (n = 721) that shows positive PD-L1 expression was significantly associated with poor survival among thyroid cancer patients (pooled hazard ratio = 3.73 [confidence interval (CI) 2.75-5.06]). Increased PD-L1 expression was also found to be significantly associated with disease recurrence (odds ratio = 1.95 [CI 1.15-3.32]) and concurrent thyroiditis (odds ratio = 1.65 [CI 1.09-2.51]).

CONCLUSIONS

The results confirm the prognostic significance of PD-L1 expression in thyroid cancer patients. PD-L1 expression has the potential to be implemented as a prognostic biomarker used to guide clinicians in identifying patients with more aggressive cancers, and for the selection of individuals that would derive durable clinical benefit from anti-PD-1/PD-L1 immunotherapy. Prospective clinical trials will be useful to support these findings.

Comparison of effect sizes between enriched and nonenriched trials of analgesics for chronic musculoskeletal pain: a systematic review

AIMS

To investigate the use of an enriched study design on the estimates of treatment effect in analgesic trials for chronic musculoskeletal pain.

METHODS

Database searches were conducted from 2004 to 2014. We included randomized placebo-controlled trials evaluating pain medications for chronic musculoskeletal pain. Methodological quality was assessed using the PEDro scale. The estimates of treatment effect on pain and adverse events were compared between enriched and nonenriched designs. Metaregression was used to assess the association between the effect size estimate and the study design controlling for analgesic dose and methodological quality.

RESULTS

We included 108 trials, of which 99 were included in the meta-analysis (n = 44 171). There were no overall differences in effect sizes between enriched and nonenriched designs for pain intensity. There was a significant difference for a reduction in any adverse events favouring enriched designs for opioids, but not for other analgesics or the outcome serious adverse events. There was an association between effect size and methodological quality, with failure to blind the outcome assessor and failure to use intention-to-treat analysis being associated with larger effect sizes.

CONCLUSIONS

There is no evidence that the use of an enriched study design changes the treatment effect size estimate for pain. There is some evidence that clinical trials that employ enriched designs report a reduced risk of adverse events in trials for chronic musculoskeletal pain, but it is unclear whether enriched designs influence estimates of serious adverse events. Features of trial design and study quality were associated with treatment effect estimates.

Pharmacists' views on implementing a disease state management program for low back pain

Pharmacists have the potential to take a lead role in the primary care management of people with acute low back pain. The aim of this study was to investigate pharmacists' views on implementing a care program for people with acute low back pain in the community pharmacy. Recruitment of pharmacists for this study took place between July 2012 and March 2013. A convenience sample of 30 pharmacists who collaborated in recruiting participants for a low back pain clinical trial in Sydney (n=15 pharmacist recruiters and n=15 non-recruiters) completed an open-ended questionnaire. There was no marked variation in responses between the two groups. Participating pharmacists were receptive to the idea of implementing a care program for people with low back pain, highlighting the need for adequate reimbursement and adequate training of staff to ensure it is successful. Pharmacists identified that the follow up of people receiving such a service is dependent on several factors such as effective reminder systems and the proximity of patients to the pharmacy.

Efficacy, Tolerability, and Dose-Dependent Effects of Opioid Analgesics for Low Back Pain: A Systematic Review and Meta-analysis

IMPORTANCE

Opioid analgesics are commonly used for low back pain, however, to our knowledge there has been no systematic evaluation of the effect of opioid dose and use of enrichment study design on estimates of treatment effect.

OBJECTIVE

To evaluate efficacy and tolerability of opioids in the management of back pain; and investigate the effect of opioid dose and use of an enrichment study design on treatment effect.

DATA SOURCES

Medline, EMBASE, CENTRAL, CINAHL, and PsycINFO (inception to September 2015) with citation tracking from eligible randomized clinical trials (RCTs).

STUDY SELECTION

Placebo-controlled RCTs in any language.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted data and assessed risk of bias. Data were pooled using a random effects model with strength of evidence assessed using the grading of recommendations assessment, development, and evaluation (GRADE).

MAIN OUTCOMES AND MEASURES

The primary outcome measure was pain. Pain and disability outcomes were converted to a common 0 to 100 scale, with effects greater than 20 points considered clinically important.

RESULTS

Of 20 included RCTs of opioid analgesics (with a total of 7925 participants), 13 trials (3419 participants) evaluated short-term effects on chronic low back pain, and no placebo-controlled trials enrolled patients with acute low back pain. In half of these 13 trials, at least 50% of participants withdrew owing to adverse events or lack of efficacy. There was moderate-quality evidence that opioid analgesics reduce pain in the short term; mean difference (MD), -10.1 (95% CI, -12.8 to -7.4). Meta-regression revealed a 12.0 point greater pain relief for every 1 log unit increase in morphine equivalent dose (P = .046). Clinically important pain relief was not observed within the dose range evaluated (40.0-240.0-mg morphine equivalents per day). There was no significant effect of enrichment study design.

CONCLUSIONS AND RELEVANCE

For people with chronic low back pain who tolerate the medicine, opioid analgesics provide modest short-term pain relief but the effect is not likely to be clinically important within guideline recommended doses. Evidence on long-term efficacy is lacking. The efficacy of opioid analgesics in acute low back pain is unknown.

Paracetamol for low back pain

BACKGROUND

Analgesic medication is the most frequently prescribed treatment for low back pain (LBP), of which paracetamol (acetaminophen) is recommended as the first choice medication. However, there is uncertainty about the efficacy of paracetamol for LBP.

OBJECTIVES

To investigate the efficacy and safety of paracetamol for non-specific LBP.

SEARCH METHODS

We conducted searches on the Cochrane Central Register of Controlled Trials (CENTRAL, which includes the Back and Neck Review Group trials register), MEDLINE, EMBASE, CINAHL, AMED, Web of Science, LILACS, and IPA from their inception to 7 August 2015. We also searched the reference lists of eligible papers and trial registry websites (WHO ICTRP and ClinicalTrials.gov).

SELECTION CRITERIA

We only considered randomised trials comparing the efficacy of paracetamol with placebo for non-specific LBP. The primary outcomes were pain and disability. We also investigated quality of life, function, adverse effects, global impression of recovery, sleep quality, patient adherence, and use of rescue medication as secondary outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the data extraction and assessed risk of bias in the included studies. We also evaluated the quality of evidence using the GRADE approach. We converted scales for pain intensity to a common 0 to 100 scale. We quantified treatment effects using mean difference for continuous outcomes and risk ratios for dichotomous outcomes. We used effect sizes and 95% confidence intervals as a measure of treatment effect for the primary outcomes. When the treatment effects were smaller than 9 points on a 0 to 100 scale, we considered the effect as small and not clinically important.

MAIN RESULTS

Our searches retrieved 4449 records, of which three trials were included in the review (n = 1825 participants), and two trials were included in the meta-analysis. For acute LBP, there is high-quality evidence for no difference between paracetamol (4 g per day) and placebo at 1 week (immediate term), 2 weeks, 4 weeks, and 12 weeks (short term) for the primary outcomes. There is high-quality evidence that paracetamol has no effect on quality of life, function, global impression of recovery, and sleep quality for all included time periods. There were also no significant differences between paracetamol and placebo for adverse events, patient adherence, or use of rescue medication. For chronic LBP, there is very low-quality evidence (based on a trial that has been retracted) for no effect of paracetamol (1 g single intravenous dose) on immediate pain reduction. Finally, no trials were identified evaluating patients with subacute LBP.

AUTHORS' CONCLUSIONS

We found that paracetamol does not produce better outcomes than placebo for people with acute LBP, and it is uncertain if it has any effect on chronic LBP.