Efficacy and safety of rofecoxib in patients with chronic low back pain: results from two 4-week, randomized, placebo-controlled, parallel-group, double-blind trials

Pharmacological interventions for patients with chronic primary musculoskeletal pain: disparity between synthesized evidence and real-world clinical practice

Introduction

Chronic primary musculoskeletal pain (CPMP) poses a major problem of public health, with high prevalence rates and economic burden. There is a wealth of clinical trials examining pharmacological interventions for patients with CPMP. Nevertheless, evidence from such trials does not necessarily mirror clinical realities.

Objectives

We aimed to compare data sets from a clinical sample with an randomized controlled trial (RCT)-based sample.

Methods

Both data sets included participants living with CPMP who received pharmacological interventions. The clinical sample was retrieved from electronic health records. The RCT-based sample stemmed from a network meta-analysis project. The following outcomes were used: demographic information, diagnosis-specific data, and pharmacological interventions (categorized according to the World Health Organization [WHO] analgesic ladder).

Results

The clinical sample consisted of 103 patients (mean age: 50.25 years; SD: 14.0) and the RCT-based samples contributed 8665 participants (mean age: 51.97 years; SD: 6.74). In both samples, the proportion of women was higher than that of men (ie, 74.8% vs 58.9%). Psychiatric disorders were the most common comorbidities in the clinic sample but also the most frequent reason for patient exclusion in RCTs. The 2 samples differed significantly in medication classified as WHO III (clinical sample: 12.9%; RCT sample: 23.5%; P = 0.023) and WHO IV (clinical sample: 23.4%; RCT sample: 8.6%; P < 0.001), yet not WHO I and II.

Conclusion

Our findings suggest a disparity between research-based study populations and clinical populations with CPMP. We advocate for future investigations on how to implement robust scientific evidence into real-world clinical practice, with a particular focus on addressing psychiatric comorbidities.

Nociceptive pain assessed by the PainDETECT questionnaire may predict response to opioid treatment for chronic low back pain

Introduction

The pharmacological management of chronic low back pain (LBP) is complex. The World Health Organisation recommends a laddered approach to pain medication usage. The PainDETECT questionnaire distinguishes between neuropathic pain (NeP), nociceptive pain (NoP), and ambiguous pain. By elucidating the difference in medication efficacy between these groups, clinicians can provide a tailored treatment plan to manage patient's pain. This study aimed to investigate the relationship between pharmacological treatments, pain categorizations, and medication efficacy as reported by patients.

Methods

A secondary retrospective analysis of a prospectively collected database was conducted involving 318 consecutively recruited patients, aged 18 years and above, who completed PainDETECT, medication history and patient reported medication efficacy questionnaires. Medication history was categorized into four lines of treatment: first line (paracetamol ± non-prescribed anti-inflammatories), second line (prescribed anti-inflammatories), third line (anticonvulsants/neuromodulators) and fourth line (opioids). Medication efficacy was measured using a three-point Likert scale: effective (+2), somewhat effective (+1), no effect (0).

Findings

The study included 120, 50, 54 and 94 patients on first line, second line, third line and fourth line treatment, respectively. The NeP group had higher mean numerical rating scale (NRS) compared to NoP group in all four lines of treatment (8.10 ± 1.59 vs. 5.47± 2.27, p < 0.001, 8.64± 1.43 vs. 5.52± 1.86, p < 0.001, 8.00± 1.07 vs. 6.37± 2.39, p < 0.01, and 8.05± 1.73 vs. 7.2± 1.29, p < 0.05). When confounding for severity of LBP as measured by NRS, the distribution of medication efficacy significantly differed amongst the NeP, ambiguous and NoP groups in patients undergoing fourth line pharmacological treatment (r2 = 8.623, p < 0.05). The NoP group exhibited significantly higher medication efficacy compared to the NeP group (U = 14.038, p < 0.05). There was no significant difference in medication efficacy across the pain classifications for first, second- and third-line treatment.

Interpretation

Opioids was the only line of treatment more effective in targeting NoP, as determined by the PainDETECT questionnaire, compared to NeP. This pioneering study illustrates the complex nature of pharmacological management for chronic LBP. It underscores the importance of tailoring pharmacological treatment plans to fit individual pain profiles and expectations instead of adopting a blanket approach to pain management.

Mawangdui-Guidance Qigong Exercise for patients with chronic non-specific low back pain: Study protocol of a randomized controlled trial

Introduction

Worldwide, there is a high frequency of chronic non-specific low back pain (CNLBP), which is a significant public health concern. The etiology is complicated and diverse, and it includes a number of risk factors such as diminished stability and weak core muscles. Mawangdui-Guidance Qigong has been employed extensively to bolster the body in China for countless years. However, the effectiveness of treating CNLBP has not been assessed by a randomized controlled trial (RCT). In order to verify the results of the Mawangdui-Guidance Qigong Exercise and examine its biomechanical mechanism, we intend to perform a randomized controlled trial.

Methods and analysis

Over the course of 4 weeks, 84 individuals with CNLBP will be randomly assigned to receive either Mawangdui-Guidance Qigong Exercise, motor control exercise, or medication (celecoxib). Electromyographic data, including muscle activation time, iEMGs, root mean square value (RMS) and median frequency (MF), will be the main outcomes. The Japanese Orthopedic Association (JOA) Score, the Mcgill Pain Questionnaire (MPQ), beta-endorphin, and substance P are examples of secondary outcomes. At the start of treatment and 4 weeks later, all outcomes will be evaluated. SPSS version 20.0 (SPSS Inc., Chicago, IL, USA) will be used for all of the analysis.

Discussion

The prospective findings are anticipated to offer an alternative treatment for CNLBP and provide a possible explanation of the mechanism of Mawangdui-Guidance Qigong Exercise on CNLBP.

Ethics and dissemination

The Sichuan Regional Ethics Review Committee on Traditional Chinese Medicine has given the study approval (Approval No. 2020KL-067). It has also registered at the website of China Clinical Trial Center Registration. The application adheres to the Declaration of Helsinki’s tenets (Version Edinburgh 2000). Peer-reviewed papers will be used to publicize the trial’s findings.

Trial registration number

ClinicalTrials.gov, identifier ChiCTR2000041080.

Pharmacotherapy for Spine-Related Pain in Older Adults

As the population ages, spine-related pain is increasingly common in older adults. While medications play an important role in pain management, their use has limitations in geriatric patients due to reduced liver and renal function, comorbid medical problems, and polypharmacy. This review will assess the evidence basis for medications used for spine-related pain in older adults, with a focus on drug metabolism and adverse drug reactions. A PubMed/OVID search crossing common spine, neck, and back pain terms with key words for older adults and geriatrics was combined with common drug classes and common drug names and limited to clinical trials and age over 65 years. The results were then reviewed with identification of commonly used drugs and drug categories: nonsteroidal anti-inflammatories (NSAIDs), acetaminophen, corticosteroids, gabapentin and pregabalin, antispastic and antispasmodic muscle relaxants, tricyclic antidepressants (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tramadol, and opioids. Collectively, 138 double-blind, placebo-controlled trials were the focus of the review. The review found a variable contribution of high-quality studies examining the efficacy of medications for spine pain primarily in the geriatric population. There was strong evidence for NSAID use with adjustments for gastrointestinal and renal risk factors. Gabapentin and pregabalin had mixed evidence for neuropathic pain. SNRIs had good evidence for neuropathic pain and a more favorable safety profile than TCAs. Tramadol had some evidence in older patients, but more so in persons aged < 65 years. Rational therapeutic choices based on geriatric spine pain diagnosis are helpful, such as NSAIDs and acetaminophen for arthritic and myofascial-based pain, gabapentinoids or duloxetine for neuropathic and radicular pain, antispastic agents for myofascial-based pain, and combination therapy for mixed etiologies. Tramadol can be well tolerated in older patients, but has risks of cognitive and classic opioid side effects. Otherwise, opioids are typically avoided in the treatment of spine-related pain in older adults due to their morbidity and mortality risk and are reserved for refractory severe pain. Whenever possible, beneficial geriatric spine pain pharmacotherapy should employ the lowest therapeutic doses with consideration of polypharmacy, potentially decreased renal and hepatic metabolism, and co-morbid medical disorders.

Comparative safety review of current treatment options for chronic low back pain and unmet needs: a narrative review

Introduction: The healthcare expenditures in the United States are substantial for the management of refractory, chronic low back pain (CLBP). The objective of this review is to summarize and evaluate the safety profiles of different pharmacological treatment options used in the management of CLBP.Areas covered: The authors conducted a search of randomized controlled trials (RCTs) assessing the safety profiles of different pharmacological agents used in the management of CLBP. This narrative review covered corticosteroids, opioids, antidepressants, gabapentinoids, nonsteroidal anti-inflammatory drugs, muscle relaxants, anti-nerve growth factor antibodies and topical agents, as monotherapy or in combination.Expert opinion: The risk-benefit ratio of a particular treatment is a subject driving the ongoing development of pharmaceuticals. The most commonly reported AEs across all drug classes are of gastrointestinal nature, followed by neurological and skin-related. These AEs include nausea, dizziness, constipation, arthralgia, headache, dry mouth, pruritus, etc. The majority of the AEs reported are not life-threatening, although they may lower patients' quality of life, thus, affecting their compliance. One of the biggest limitations of our review stems from the paucity of safety assessments in published RCTs. Advances in our understanding of the neurobiology of pain will promote development of new therapeutic strategies.

Chronic nonspecific (musculoskeletal) low back pain. Guidelines of the Russian Society for the Study of Pain (RSSP)

Examination of a patient with chronic low back pain (LBP) is aimed at eliminating its specific cause and assessing the social and psychological factors of chronic pain. The diagnosis of chronic nonspecific (musculoskeletal) LBP is based on the exclusion of a specific cause of pain, discogenic radiculopathy, and lumbar stenosis. It is advisable to identify possible pain sources: pathology of intervertebral disc pathology, facet joints, and sacroiliac joint and myofascial syndrome.

An integrated multidisciplinary approach (a high level of evidence), including therapeutic exercises, physical activity optimization, psychological treatments (cognitive behavioral therapy), an educational program (back pain school for patients), and manual therapy, is effective in treating chronic musculoskeletal LBP. For pain relief, one may use nonsteroidal anti-inflammatory drugs in minimally effective doses and in a short cycle, muscle relaxants, and a capsaicin patch, and, if there is depressive disorder, antidepressants (a medium level of evidence). Radiofrequency denervation or therapeutic blockages with anesthetics and glucocorticoids (damage to the facet joints, sacroiliac joint), back massage, and acupuncture (a low level of evidence) may be used in some patients.

Therapeutic exercises and an educational program (the prevention of excessive loads and prolonged static and uncomfortable postures and the use of correct methods for lifting weights, etc.) are recommended for preventive purposes. 

Alternatives to Opioids in the Pharmacologic Management of Chronic Pain Syndromes: A Narrative Review of Randomized, Controlled, and Blinded Clinical Trials

Chronic pain exerts a tremendous burden on individuals and societies. If one views chronic pain as a single disease entity, then it is the most common and costly medical condition. At present, medical professionals who treat patients in chronic pain are recommended to provide comprehensive and multidisciplinary treatments, which may include pharmacotherapy. Many providers use nonopioid medications to treat chronic pain; however, for some patients, opioid analgesics are the exclusive treatment of chronic pain. However, there is currently an epidemic of opioid use in the United States, and recent guidelines from the Centers for Disease Control (CDC) have recommended that the use of opioids for nonmalignant chronic pain be used only in certain circumstances. The goal of this review was to report the current body of evidence-based medicine gained from prospective, randomized-controlled, blinded studies on the use of nonopioid analgesics for the most common noncancer chronic pain conditions. A total of 9566 studies were obtained during literature searches, and 271 of these met inclusion for this review. Overall, while many nonopioid analgesics have been found to be effective in reducing pain for many chronic pain conditions, it is evident that the number of high-quality studies is lacking, and the effect sizes noted in many studies are not considered to be clinically significant despite statistical significance. More research is needed to determine effective and mechanism-based treatments for the chronic pain syndromes discussed in this review. Utilization of rigorous and homogeneous research methodology would likely allow for better consistency and reproducibility, which is of utmost importance in guiding evidence-based care.

Clinical Efficacy of Celecoxib Compared to Acetaminophen in Chronic Nonspecific Low Back Pain: Results of a Randomized Controlled Trial

OBJECTIVE

In this randomized controlled trial, we compared the effect of celecoxib and acetaminophen on pain and magnetic resonance imaging (MRI) scores in patients with chronic nonspecific low back pain.

METHODS

A total of 50 patients with chronic nonspecific low back pain were blindly randomized into 2 groups treated with celecoxib (200 mg twice daily) or acetaminophen (500 mg twice daily). Outcome measures included total back pain, nocturnal back pain, Oswestry Disability Index (ODI) scores, the Short Form 36 health survey to assess physical and mental status, and patient global assessment. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index, and Bath Ankylosing Spondylitis Metrology Index scores were also assessed before and after the therapy. The Spondyloarthritis Research Consortium of Canada scoring method was used to evaluate spinal MRI changes.

RESULTS

Celecoxib showed a superior effect on total back pain, ODI, BASDAI, nocturnal back pain, and patient global assessment, compared to acetaminophen (P < 0.05). The number of patients with a significant change in back pain scales was higher in the celecoxib arm (ODI 34.8% versus 4.5%, nocturnal back pain 41.7% versus 9.1%, total back pain 33.3% versus 9.1%, and BASDAI 30.4% versus 9.1%; P < 0.01 for all). The responsiveness to celecoxib, calculated by Guyatt's Responsiveness Index, was 1.62, 1.28, 1.27, and 0.58 for the ODI, total back pain, BASDAI, and nocturnal back pain, respectively. The MRI scores for sacroiliac joints and spine showed no significant change with either treatment when compared with baseline values (P > 0.05).

CONCLUSION

There was superior efficacy of celecoxib compared with acetaminophen in chronic nonspecific low back pain. Inflammatory lesions of sacroiliac joints and spine are commonly seen in nonspecific low back pain, but these lesions did not change with either celecoxib or acetaminophen treatments and were not associated with clinical response to either agent.

Non-steroidal anti-inflammatory drugs for spinal pain: a systematic review and meta-analysis

BACKGROUND

While it is now clear that paracetamol is ineffective for spinal pain, there is not consensus on the efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) for this condition. We performed a systematic review with meta-analysis to determine the efficacy and safety of NSAIDs for spinal pain.

METHODS

We searched MEDLINE, EMBASE, CINAHL, CENTRAL and LILACS for randomised controlled trials comparing the efficacy and safety of NSAIDs with placebo for spinal pain. Reviewers extracted data, assessed risk of bias and evaluated the quality of evidence using the Grade of Recommendations Assessment, Development and Evaluation approach. A between-group difference of 10 points (on a 0-100 scale) was used for pain and disability as the smallest worthwhile effect, as well as to calculate numbers needed to treat. Random-effects models were used to calculate mean differences or risk ratios with 95% CIs.

RESULTS

We included 35 randomised placebo-controlled trials. NSAIDs reduced pain and disability, but provided clinically unimportant effects over placebo. Six participants (95% CI 4 to 10) needed to be treated with NSAIDs, rather than placebo, for one additional participant to achieve clinically important pain reduction. When looking at different types of spinal pain, outcomes or time points, in only 3 of the 14 analyses were the pooled treatment effects marginally above our threshold for clinical importance. NSAIDs increased the risk of gastrointestinal reactions by 2.5 times (95% CI 1.2 to 5.2), although the median duration of included trials was 7 days.

CONCLUSIONS

NSAIDs are effective for spinal pain, but the magnitude of the difference in outcomes between the intervention and placebo groups is not clinically important. At present, there are no simple analgesics that provide clinically important effects for spinal pain over placebo. There is an urgent need to develop new drug therapies for this condition.

Non-steroidal anti-inflammatory drugs for chronic low back pain

BACKGROUND

Chronic back pain is an important health problem. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used to treat people with low back pain, especially people with acute back pain. Short term NSAID use is also recommended for pain relief in people with chronic back pain. Two types of NSAIDs are available and used to treat back pain: non-selective NSAIDs and selective COX-2 NSAIDs. In 2008, a Cochrane review identified a small but significant effect from NSAIDs compared to placebo in people with chronic back pain. This is an update of the Cochrane review published in 2008 and focuses on people with chronic low back pain.

OBJECTIVES

To determine if NSAIDs are more efficacious than various comparison treatments for non-specific chronic low back pain and if so, which type of NSAID is most efficacious.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, PubMed and two clinical trials registry databases up to 24 June 2015 for randomized controlled trials (RCTs) published in English, German or Dutch. We also screened references cited in relevant reviews.

SELECTION CRITERIA

We included RCTs (double-blind and single-blind) of NSAIDs used to treat people with chronic low back pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened trials for inclusion in this Cochrane review according to the inclusion criteria. One review author extracted the data, and a second review author checked the data. Two review authors independently evaluated the risk of bias of all included trials. If data were clinically homogeneous, we performed a meta-analysis and assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We included 13 trials in this Cochrane review. Ten studies were at 'low' risk of bias. Six studies compared NSAIDs with placebo, and included 1354 participants in total. There is low quality evidence that NSAIDs are more effective than placebo, with a mean difference in pain intensity score from baseline of -3.30 (95% CI -5.33 to -1.27) on a 0 to 100 visual analogue scale (VAS) with a median follow-up of 56 days (interquartile range (IQR) 13 to 91 days). Four studies measured disability using the Roland Morris Disability Questionnaire. There is low quality evidence that NSAIDs are more effective than placebo on disability, with a mean difference from baseline of -0.85 (95% CI -1.30 to -0.40) on a scale from 0 to 24 with a median follow-up of 84 days (IQR 42 to 105 days). All six placebo controlled studies also reported adverse events, and suggested that adverse events are not statistically significant more frequent in participants using NSAIDs compared to placebo (RR 1.04, 95% CI 0.92 to 1.17). Due to the relatively small sample size and relatively short follow-up in most included trials, it is likely that the proportion of patients experiencing an adverse event is underestimated.Two studies compared different types of non-selective NSAIDs, namely ibuprofen versus diclofenac and piroxicam versus indomethacin. The trials did not find any differences between these NSAID types, but both trials had small sample sizes. One trial reported no differences in pain intensity between treatment groups that used selective or non-selective NSAIDs. One other trial compared diflunisal with paracetamol and showed no difference in improvement from baseline on pain intensity score. One trial showed a better global improvement in favour of celecoxib versus tramadol.One included trial compared NSAIDs with 'home-based exercise'. Disability improved more in participants who did exercises versus participants receiving NSAIDs, but pain scores were similar.

AUTHORS' CONCLUSIONS

Six of the 13 included RCTs showed that NSAIDs are more effective than placebo regarding pain intensity. NSAIDs are slightly more effective than placebo regarding disability. However, the magnitude of the effects is small, and the level of evidence was low. When we only included RCTs at low risk of bias, differences in effect between NSAIDs and placebo were reduced. We identified no difference in efficacy between different NSAID types, including selective versus non-selective NSAIDs. Due to inclusion of RCTs only, the relatively small sample sizes and relatively short follow-up in most included trials, we cannot make firm statements about the occurrence of adverse events or whether NSAIDs are safe for long-term use.

WITHDRAWN: Medicinal and injection therapies for mechanical neck disorders

Withdrawn due to non‐compliance with The Cochrane Collaboration’s Commercial Sponsorship Policy

The editorial group responsible for this previously published document have withdrawn it from publication.

The measurement of symptoms and side effects in clinical trials of chronic pain

Clinical trials in chronic pain have used various methods to assess the effect of medications. In addition to measuring symptom relief, researchers must also address adverse events (AEs) associated with the medication to evaluate overall therapeutic results. This paper reviews methods of measuring symptoms and AEs, including passive capture, scripted prompting, prospective assessments of side effects of interest, and prospective comprehensive symptom checklists. Methods of measuring therapeutic results have advantages and disadvantages. Although passive AE capture (unscripted, open-ended questions about symptoms) is not constrained by preconceptions of potential AEs, it sometimes fails to capture clinically significant AEs. Scripted prompting (prespecified, scripted, open-ended questions about symptoms) is likely to address the latter problem but preclude consistency across trials. Prospective assessments (prespecified symptom inventories) can offer greater sensitivity and consistency in detecting side effects of specific treatments. Comprehensive symptom distress inventories can be more sensitive measures of overall treatment benefit, which may be important when efficacy, passive AE capture, and comprehensive quality of life (QOL) batteries fail to differentiate between treatments. In cancer populations these inventories have been statistically correlated with survival and other important clinical outcomes, even after controlling for disease status, global QOL, psychological state, and performance status. Other important considerations are patient perceptions of the importance of symptoms, the correlations between QOL and symptom distress, and the usefulness of global ratings, in which patients integrate any perceived benefits of the medication with tolerability and other factors, such as convenience and cost.

An examination of the observed placebo effect associated with the treatment of low back pain - a systematic review

OBJECTIVE

To determine whether the nonspecific effects that occur following the use of sham interventions to treat nonspecific low back pain (LBP) are large enough to be considered clinically meaningful.

DESIGN

Electronic databases were searched systematically for randomized placebo-controlled trials of interventions for LBP that used sham ultrasound, sham laser or sham drug therapy as the placebo control. Study selection was accomplished via independent evaluation of scientific admissibility by three reviewers and final decisions of inclusion were based on consensus.

RESULTS

None of the studies using sham ultrasound as the placebo control in the treatment of LBP were acceptable for inclusion. Twelve studies were included in the present evaluation of the placebo effect - eight trials that met the strict inclusion criteria for best evidence (three using sham laser placebo and five using sham medication placebo) and four sham medication studies that 'just missed' the inclusion criteria for best evidence. Although the evidence from studies using sham laser was inconclusive, the present review did find a clinically meaningful change in LBP scores following the use of sham oral medications.

CONCLUSIONS

The present best-evidence review found a clinically meaningful change in pain scores following the use of sham oral medications for the treatment of nonspecific LBP. This finding suggests that further clinical research is warranted to identify which patient subgroups could benefit most from such treatment and to distinguish the true contribution of the placebo effect from other nonspecific effects.

Pharmacotherapy of low back pain: targeting nociceptive and neuropathic pain components

AIM

To review pharmacological management of chronic low back pain (LBP), with respect to management of nociceptive and neuropathic components.

METHODS

Studies were identified by a PubMed search of English-language papers from the last 10  years, with additional hand searches of relevant reviews.

DISCUSSION

Paracetamol, non-steroidal anti-inflammatory drugs and cyclo-oxygenase-2 inhibitors target the nociceptive component of chronic LBP, and do not affect neuropathic pain mechanisms. Antidepressants target the neuropathic component of chronic LBP; however, conflicting efficacy results have been reported. Opioids target both nociceptive and to a lesser extent neuropathic pain. They are effective in chronic LBP, but many patients require higher doses or combination treatment. The long-term efficacy of opioids in chronic LBP has been questioned because of the absence of high-quality data and concerns regarding tolerability and dependence. The topical preparation lidocaine 5% plaster, indicated in post-herpetic neuralgia, is effective in localized neuropathic pain in patients with chronic LBP. Pregabalin is ineffective as monotherapy for chronic LBP but is effective when combined with celecoxib or opioids. Muscle relaxant monotherapy is ineffective in chronic LBP. Combination therapy is often necessary in patients with chronic LBP, in order to manage both nociceptive and neuropathic pain components.

CONCLUSION

Chronic LBP often comprises both nociceptive and neuropathic components, therefore a multimodal and individualized treatment approach is necessary. Combining drugs with different mechanisms of action (e.g. an agent with µ-receptor activity plus an agent of a different class) represents a rational approach to management of chronic LBP with both nociceptive and neuropathic components.

A systematic review on the effectiveness of pharmacological interventions for chronic non-specific low-back pain

The objective of this review was to determine the effectiveness of pharmacological interventions [i.e., non-steroid anti-inflammatory drugs (NSAIDs), muscle relaxants, antidepressants, and opioids] for non-specific chronic low-back pain (LBP). Existing Cochrane reviews for the four interventions were screened for studies fulfilling the inclusion criteria. Then, the literature searches were updated. Only randomized controlled trials on adults (≥18 years) with chronic (≥12 weeks) non-specific LBP and evaluation of at least one of the main clinically relevant outcome measures (pain, functional status, perceived recovery, or return to work) were included. The GRADE approach was used to determine the quality of evidence. A total of 17 randomized controlled trials was included: NSAIDs (n = 4), antidepressants (n = 5), and opioids (n = 8). No studies were found for muscle relaxants; 14 studies had a low risk of bias. The studies only reported effects on the short term (<3 months). The overall quality of the evidence was low. NSAIDs and opioids seem to lead to a somewhat higher relief in pain on the short term, as compared to placebo, in patients with non-specific chronic low back pain; opioids seem to have a small effect in improving function for a selection of patients who responded with an exacerbation of their symptoms after stopping their medication. However, both types of medication show more adverse effects than placebo. There seems to be no difference in effect between antidepressants and placebo in patients with non-specific chronic LBP.

Research design considerations for confirmatory chronic pain clinical trials: IMMPACT recommendations

There has been an increase in the number of chronic pain clinical trials in which the treatments being evaluated did not differ significantly from placebo in the primary efficacy analyses despite previous research suggesting that efficacy could be expected. These findings could reflect a true lack of efficacy or methodological and other aspects of these trials that compromise the demonstration of efficacy. There is substantial variability among chronic pain clinical trials with respect to important research design considerations, and identifying and addressing any methodological weaknesses would enhance the likelihood of demonstrating the analgesic effects of new interventions. An IMMPACT consensus meeting was therefore convened to identify the critical research design considerations for confirmatory chronic pain trials and to make recommendations for their conduct. We present recommendations for the major components of confirmatory chronic pain clinical trials, including participant selection, trial phases and duration, treatment groups and dosing regimens, and types of trials. Increased attention to and research on the methodological aspects of confirmatory chronic pain clinical trials has the potential to enhance their assay sensitivity and ultimately provide more meaningful evaluations of treatments for chronic pain.

Do COX-2 inhibitors raise blood pressure more than nonselective NSAIDs and placebo? An updated meta-analysis

BACKGROUND

Both COX-2 selective inhibitors (coxibs) and nonselective (ns)-NSAIDs elevate blood pressure (BP) and this may contribute to excess cardiovascular (CV) events. A number of recent large-scale randomized clinical trials (RCTs) comparing coxibs (including newer agents, lumiracoxib and etoricoxib) to both ns-NSAIDs and placebo have been reported, permitting an update to earlier BP analyses of these agents.

DATA SOURCES/SYNTHESIS

Our search yielded 51 RCTs involving coxibs published before April 2008 with a total of 130 541 participants in which BP data were available. The Der Simonian and Laird random effects method for dichotomous variables was used to produce risk ratios (RR) for development of hypertension.

RESULTS

For coxibs versus placebo, there was a RR of 1.49 (1.18-1.88, P = 0.04) in the development of new hypertension. For coxibs versus ns-NSAIDs, the RR was 1.12 (0.93-1.35, P = 0.23). These results were mainly driven by rofecoxib, with a RR of 1.87 (1.63-2.14, P = 0.08) versus placebo, and etoricoxib, with a RR of 1.52 (1.39-1.66, P = 0.01) versus ns-NSAID.

CONCLUSION

On the basis of this updated meta-analysis, coxibs appear to produce greater hypertension than either ns-NSAIDs or placebo. However, this response was heterogeneous, with markedly raised BP associated with rofecoxib and etoricoxib, whereas celecoxib, valdecoxib and lumiracoxib appeared to have little BP effect. The relationship of this increased risk of hypertension to subsequent adverse CV outcomes requires further investigation and prospective RCTs.

Pooled analysis of rofecoxib placebo-controlled clinical trial data: lessons for postmarket pharmaceutical safety surveillance

BACKGROUND

In September 2004, rofecoxib was voluntarily withdrawn from the worldwide market. Our objective was to determine whether and when analysis of published and unpublished placebo-controlled trials could have revealed cardiovascular risk associated with rofecoxib before its withdrawal as an example to inform future postmarket pharmaceutical safety surveillance efforts.

METHODS

We conducted a cumulative subject-level pooled analysis of data from all randomized, placebo-controlled trials of rofecoxib conducted by the manufacturer before September 2004. Our main outcome measurement was incidence of any investigator-reported death from any cause or cardiovascular thromboembolic (CVT) adverse event.

RESULTS

We identified 30 randomized, placebo-controlled trials of rofecoxib that enrolled a combined 20 152 subjects. Trial duration ranged from 4 weeks to 4 years; enrollment ranged from 17 to 2586 subjects prescribed either rofecoxib or placebo; and rofecoxib dose ranged from 12.5 mg to 50 mg. As of December 2000, 21 of these trials had been completed (70%), and the risk of a CVT adverse event or death was greater among subjects assigned to the rofecoxib group (rate ratio [RR], 2.18; 95% confidence interval [CI], 0.93-5.81) (P = .07), raising concerns from a safety standpoint. Subsequently collected data through June 2001 showed that rofecoxib was associated with a 35% increased risk of a CVT adverse event or death (RR, 1.35; 95% CI, 1.00-1.96) (P = .05). Analyzing data available as of April 2002, we found a 39% increased risk (RR, 1.39; 95% CI, 1.07-1.80) (P = .02), and using data available as of September 2004, we found a 43% increased risk (RR,1.43; 95% CI, 1.16-1.76) (P < .001).

CONCLUSION

Cumulative pooled analysis of all randomized, placebo-controlled trials demonstrates a trend toward increased cardiovascular risk associated with rofecoxib compared with placebo as early as December 2000, the comparison reaching a P value of .05 by June 2001, nearly 3(1/2) years before the manufacturer's voluntary market withdrawal.

Periganglionic inflammation elicits a distally radiating pain hypersensitivity by promoting COX-2 induction in the dorsal root ganglion

We have developed a model in which inflammation contiguous to and within a dorsal root ganglion (DRG) was generated by local application of complete Freund's adjuvant (CFA) to the L4 lumbar spinal nerve as it exits from the intervertebral foramen. The periganglionic inflammation (PGI) elicited a marked reduction in withdrawal threshold to mechanical stimuli and an increase in heat pain sensitivity in the ipsilateral hindpaw in the absence of any hindpaw inflammation. The pain sensitivity appeared within hours and lasted for a week. The PGI also induced a prominent increase in IL-1beta and TNF-alpha levels in the DRG and of cyclooxygenase-2 (COX-2) expression in neurons and satellite cells. A selective COX-2 inhibitor reduced the PGI-induced hyperalgesia. We also show that IL-1beta induces COX-2 expression and prostaglandin release in DRG neurons in vitro in a MAP kinase-dependent fashion. The COX-2 induction was prevented by ERK and p38 inhibitors. We conclude that periganglionic inflammation increases cytokine levels, including IL-1beta, leading to the transcription of COX-2 and prostaglandin production in the affected DRG, and thereby to the development of a dermatomally distributed pain hypersensitivity.

Analgesic effects of treatments for non-specific low back pain: a meta-analysis of placebo-controlled randomized trials

OBJECTIVE

Estimates of treatment effects reported in placebo-controlled randomized trials are less subject to bias than those estimates provided by other study designs. The objective of this meta-analysis was to estimate the analgesic effects of treatments for non-specific low back pain reported in placebo-controlled randomized trials.

METHODS

Medline, Embase, Cinahl, PsychInfo and Cochrane Central Register of Controlled Trials databases were searched for eligible trials from earliest records to November 2006. Continuous pain outcomes were converted to a common 0-100 scale and pooled using a random effects model.

RESULTS

A total of 76 trials reporting on 34 treatments were included. Fifty percent of the investigated treatments had statistically significant effects, but for most the effects were small or moderate: 47% had point estimates of effects of <10 points on the 100-point scale, 38% had point estimates from 10 to 20 points and 15% had point estimates of >20 points. Treatments reported to have large effects (>20 points) had been investigated only in a single trial.

CONCLUSIONS

This meta-analysis revealed that the analgesic effects of many treatments for non-specific low back pain are small and that they do not differ in populations with acute or chronic symptoms.

Imperfect placebos are common in low back pain trials: a systematic review of the literature

The placebo is an important tool to blind patients to treatment allocation and therefore minimise some sources of bias in clinical trials. However, placebos that are improperly designed or implemented may introduce bias into trials. The purpose of this systematic review was to evaluate the adequacy of placebo interventions used in low back pain trials. Electronic databases were searched systematically for randomised placebo-controlled trials of conservative interventions for low back pain. Trial selection and data extraction were performed by two reviewers independently. A total of 126 trials using over 25 different placebo interventions were included. The strategy most commonly used to enhance blinding was the provision of structurally equivalent placebos. Adequacy of blinding was assessed in only 13% of trials. In 20% of trials the placebo intervention was a potentially genuine treatment. Most trials that assessed patients' expectations showed that the placebo generated lower expectations than the experimental intervention. Taken together, these results demonstrate that imperfect placebos are common in low back pain trials; a result suggesting that many trials provide potentially biased estimates of treatment efficacy. This finding has implications for the interpretation of published trials and the design of future trials. Implementation of strategies to facilitate blinding and balance expectations in randomised groups need a higher priority in low back pain research.

Non-steroidal anti-inflammatory drugs for low back pain

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most frequently prescribed medications worldwide and are widely used for patients with low-back pain. Selective COX-2 inhibitors are currently available and used for patients with low-back pain.

OBJECTIVES

The objective was to assess the effects of NSAIDs and COX-2 inhibitors in the treatment of non-specific low-back pain and to assess which type of NSAID is most effective.

SEARCH STRATEGY

We searched the MEDLINE and EMBASE databases and the Cochrane Central Register of Controlled Trials up to and including June 2007 if reported in English, Dutch or German. We also screened references given in relevant reviews and identified trials.

SELECTION CRITERIA

Randomised trials and double-blind controlled trials of NSAIDs in non-specific low-back pain with or without sciatica were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed methodological quality. All studies were also assessed on clinical relevance, from which no further interpretations or conclusions were drawn. If data were considered clinically homogeneous, a meta-analysis was performed. If data were lacking for clinically homogeneous trials, a qualitative analysis was performed using a rating system with four levels of evidence (strong, moderate, limited, no evidence).

MAIN RESULTS

In total, 65 trials (total number of patients = 11,237) were included in this review. Twenty-eight trials (42%) were considered high quality. Statistically significant effects were found in favour of NSAIDs compared to placebo, but at the cost of statistically significant more side effects. There is moderate evidence that NSAIDs are not more effective than paracetamol for acute low-back pain, but paracetamol had fewer side effects. There is moderate evidence that NSAIDs are not more effective than other drugs for acute low-back pain. There is strong evidence that various types of NSAIDs, including COX-2 NSAIDs, are equally effective for acute low-back pain. COX-2 NSAIDs had statistically significantly fewer side-effects than traditional NSAIDs.

AUTHORS' CONCLUSIONS

The evidence from the 65 trials included in this review suggests that NSAIDs are effective for short-term symptomatic relief in patients with acute and chronic low-back pain without sciatica. However, effect sizes are small. Furthermore, there does not seem to be a specific type of NSAID which is clearly more effective than others. The selective COX-2 inhibitors showed fewer side effects compared to traditional NSAIDs in the RCTs included in this review. However, recent studies have shown that COX-2 inhibitors are associated with increased cardiovascular risks in specific patient populations.

Evidence-informed management of chronic low back pain with nonsteroidal anti-inflammatory drugs, muscle relaxants, and simple analgesics

The management of chronic low back pain (CLBP) has proven to be very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing amongst available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to CLBP, the North American Spine Society has sponsored this special focus issue of The Spine Journal, titled Evidence-Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP.

Effect sizes of non-surgical treatments of non-specific low-back pain

Numerous randomized trials have been published investigating the effectiveness of treatments for non-specific low-back pain (LBP) either by trials comparing interventions with a no-treatment group or comparing different interventions. In trials comparing two interventions, often no differences are found and it raises questions about the basic benefit of each treatment. To estimate the effect sizes of treatments for non-specific LBP compared to no-treatment comparison groups, we searched for randomized controlled trials from systematic reviews of treatment of non-specific LBP in the latest issue of the Cochrane Library, issue 2, 2005 and available databases until December 2005. Extracted data were effect sizes estimated as Standardized Mean Differences (SMD) and Relative Risk (RR) or data enabling calculation of effect sizes. For acute LBP, the effect size of non-steroidal anti-inflammatory drugs (NSAIDs) and manipulation were only modest (ES: 0.51 and 0.40, respectively) and there was no effect of exercise (ES: 0.07). For chronic LBP, acupuncture, behavioral therapy, exercise therapy, and NSAIDs had the largest effect sizes (SMD: 0.61, 0.57, and 0.52, and RR: 0.61, respectively), all with only a modest effect. Transcutaneous electric nerve stimulation and manipulation had small effect sizes (SMD: 0.22 and 0.35, respectively). As a conclusion, the effect of treatments for LBP is only small to moderate. Therefore, there is a dire need for developing more effective interventions.

A systematic review of measures used to assess chronic musculoskeletal pain in clinical and randomized controlled clinical trials

There are many types of pain assessments available to researchers conducting clinical trials, ranging from simple, single-item Visual Analog Scale (VAS) questions through extensive, multidimensional inventories. The primary question addressed in this survey of top-tier medical journals was: Which pain assessments are most commonly used in trials? Articles addressing chronic musculoskeletal pain in clinical trials were identified in 7 major medical journals for the year 2003. A total of 50 studies (1476 total original research articles reviewed) met selection criteria, and from these we identified 28 types of pain assessments. Selected studies were classified according to the dimensions of pain assessed, the type of scale and descriptors/anchors used, and the reporting period specified. The most frequently used assessments were the single-item VAS and the Numeric Rating Scale; multidimensional inventories were used infrequently. There was considerable variability in the instructions patients received about the period to consider when evaluating their pain, and many studies provided only cursory information about their assessments in the methods. Overall, it appears that clinical trials use simple measures of pain and that there is no widely accepted standard for clinical pain assessment that would facilitate comparison of outcomes across trials.

PERSPECTIVE

This review highlights the heterogeneity of pain outcome measures used and the abundance of single-item measures in clinical trials. Although there are many pain outcome measures available to clinical researchers, more consistency in the field should be encouraged so that results between studies can be compared.

Medicinal and injection therapies for mechanical neck disorders

BACKGROUND

Controversy persists regarding medicinal therapies and injections.

OBJECTIVES

To determine the effects of medication and injections on primary outcomes (e.g. pain) for adults with mechanical neck disorders and whiplash.

SEARCH STRATEGY

We searched CENTRAL, MANTIS, CINAHL from their start to May 2006; MEDLINE and EMBASE to December 2006. We scrutinised reference lists for other trials.

SELECTION CRITERIA

We included randomised controlled trials with adults with neck disorders, with or without associated headache or radicular findings. We considered medicinal and injection therapies, regardless of route of administration.

DATA COLLECTION AND ANALYSIS

Two authors independently selected articles, abstracted data and assessed methodological quality. When clinical heterogeneity was absent, we combined studies using random-effects models.

MAIN RESULTS

We found 36 trials that examined the effects of oral NSAIDs, psychotropic agents, steroid injections, and anaesthetic agents. Trials had a mean of 3.1 on the Jadad Scale for methodological quality; 70% were high quality. For acute whiplash, administering intravenous methylprednisolone within eight hours of injury reduced pain at one week (SMD -0.90, 95% CI -1.57 to -0.24), and sick leave but not pain at six months compared to placebo in one trial. For chronic neck disorders at short-term follow-up, intramuscular injection of lidocaine was superior to placebo (SMD -1.36, 95% CI -1.93 to -0.80); NNT 3, treatment advantage 45% and dry needling, but similar to ultrasound in one trial each. In chronic neck disorders with radicular findings, epidural methylprednisolone and lidocaine reduced neck pain and improved function more than when given by intramuscular route at one-year follow-up, in one trial. In subacute and chronic neck disorders, muscle relaxants, analgesics and NSAIDs had limited evidence and unclear benefits. In participants with chronic neck disorders with or without radicular findings or headache, there was moderate evidence from five high quality trials that Botulinum toxin A intramuscular injections had similar effects to saline in improving pain (pooled SMD: -0.39, 95%CI -1.25 to 0.47), disability or global perceived effect.

AUTHORS' CONCLUSIONS

The major limitations are the lack of replication of the findings and sufficiently large trials. There is moderate evidence for the benefit of intravenous methylprednisolone given within eight hours of acute whiplash, from a single trial. Lidocaine injection into myofascial trigger points appears effective in two trials. There is moderate evidence that Botulinum toxin A is not superior to saline injection for chronic MND. Muscle relaxants, analgesics and NSAIDs had limited evidence and unclear benefits.

Chronic low back pain in a working-age adult

Low back pain is an extremely common patient complaint. Most cases resolve fairly quickly after the acute episode. However, a small but significant number of patients develop chronic low back pain; a persistent disabling condition. Patients suffer from unremitting pain and often become functionally impaired. Multiple patient characteristics have been identified that place patients at risk for developing chronic low back pain. Currently, it is difficult to find clinical guidelines on how best to manage chronic low back pain, and it remains a substantial treatment challenge for both physicians and patients. The causes, risk factors, prognosis and treatment strategies for chronic low back pain will be discussed in this chapter. The evidence regarding different pharmacological and non-pharmacological treatment modalities will be reviewed and a logical, focused treatment strategy will be outlined.

Outcome of non-invasive treatment modalities on back pain: an evidence-based review

At present, there is an increasing international trend towards evidence-based health care. The field of low back pain (LBP) research in primary care is an excellent example of evidence-based health care because there is a huge body of evidence from randomized trials. These trials have been summarized in a large number of systematic reviews. This paper summarizes the best available evidence from systematic reviews conducted within the framework of the Cochrane Back Review Group on non-invasive treatments for non-specific LBP. Data were gathered from the latest Cochrane Database of Systematic Reviews 2005, Issue 2. The Cochrane reviews were updated with additional trials, if available. Traditional NSAIDs, muscle relaxants, and advice to stay active are effective for short-term pain relief in acute LBP. Advice to stay active is also effective for long-term improvement of function in acute LBP. In chronic LBP, various interventions are effective for short-term pain relief, i.e. antidepressants, COX2 inhibitors, back schools, progressive relaxation, cognitive-respondent treatment, exercise therapy, and intensive multidisciplinary treatment. Several treatments are also effective for short-term improvement of function in chronic LBP, namely COX2 inhibitors, back schools, progressive relaxation, exercise therapy, and multidisciplinary treatment. There is no evidence that any of these interventions provides long-term effects on pain and function. Also, many trials showed methodological weaknesses, effects are compared to placebo, no treatment or waiting list controls, and effect sizes are small. Future trials should meet current quality standards and have adequate sample size.

Does osteoarthritis of the lumbar spine cause chronic low back pain?

The lumbar spine is a common location for osteoarthritis. The axial skeleton demonstrates the same classic alterations of cartilage loss, joint instability, and osteophytosis characteristic of symptomatic disease in the appendages. Despite these similarities, questions remain regarding the lumbar spine facet joints as a source of chronic back pain. The facet joints undergo a progression of degeneration that may result in pain. The facet joints have sensory input from two spinal levels that makes localization of pain difficult. Radiographic studies describe intervertebral disc abnormalities in asymptomatic individuals that are associated with, but not synonymous for, osteoarthritis. Patients who do not have osteoarthritis of the facet joints on magnetic resonance scan do not have back pain. Single photon emission computed tomography scans of the axial skeleton are able to identify painful facet joints with increased activity that may be helped by local anesthetic injections. Low back pain is responsive to therapies that are effective for osteoarthritis in other locations. Osteoarthritis of the lumbar spine does cause low back pain.

A 1-year follow-up after a pilot study with Doloteffin for low back pain

OBJECTIVE

To complete a year's follow-up on patients from a 6-week double-blind pilot comparison between 44 Doloteffin patients and 44 rofecoxib patients being treated for acute exacerbations of chronic low back pain.

METHODS

38 "ex-Doloteffin" (ex-D) and 35 "ex-rofecoxib" (ex-R) received Doloteffin containing 60 mg harpagoside per day for up to 54 weeks. Pain, additional analgesics, mobility, general health and adverse events were assessed from diary records and at 6-week visits.

RESULTS

53 patients remained in the follow-up at 24 weeks and 43 at 54 weeks. There was never any convincing difference between ex-D and ex-R patients in the number of patients remaining in follow-up, diary pain scores, additional analgesics, Arhus Index and health assessment questionnaire scores (HAQ). Individual fluctuations notwithstanding, the follow-up showed a slight overall improvement on the improvements in Arhus and HAQ scores achieved in the pilot study (MANOVA p = 0.016). Of the 21761 patient-days, the respective percentages with no, mild, moderate, severe and excruciating pain were 28%, 39%, 22%, 8.5% and 1.5%, respectively. Few patients requested additional treatments for their pain. Three patients suffered from minor adverse drug reactions.

CONCLUSION

Long-term treatment with Doloteffin was well tolerated. Ex-R and ex-D patients behaved similarly during the follow-up.

Does osteoarthritis of the lumbar spine cause chronic low back pain?

The lumbar spine is a common location for osteoarthritis. The axial skeleton demonstrates the same classic alterations of cartilage loss, joint instability, and osteophytosis characteristic of symptomatic disease in the appendages. Despite these similarities, questions remain regarding the lumbar spine facet joints as a source of chronic back pain. The facet joints undergo a progression of degeneration that may result in pain. The facet joints have sensory input from two spinal levels that makes localization of pain difficult. Radiographic studies describe intervertebral disc abnormalities in asymptomatic individuals that are associated with, but not synonymous for, osteoarthritis. Patients who do not have osteoarthritis of the facet joints on magnetic resonance scan do not have back pain. Single photon emission computed tomography scans of the axial skeleton are able to identify painful facet joints with increased activity that may be helped by local anesthetic injections. Low back pain is responsive to therapies that are effective for osteoarthritis in other locations. Osteoarthritis of the lumbar spine does cause low back pain.