Comparing pain intensity rating scales in acute postoperative pain: boundary values and category disagreements

Pain intensity assessment scales are important in evaluating postoperative pain and guiding management. Different scales can be used for patients to self-report their pain, but research determining cut points between mild, moderate and severe pain has been limited to studies with < 1500 patients. We examined 13,017 simultaneous acute postoperative pain ratings from 913 patients taken at rest and on activity, between 4 h and 48 h following surgery using both a verbal rating scale (no, mild, moderate or severe pain) and 0-100 mm visual analogue scale. We determined the best cut points on the visual analogue scale between mild and moderate pain as 35 mm, and moderate and severe pain as 80 mm. These remained consistent for pain at rest and on activity, and over time. We also explored the presence of category disagreements, defined as patients verbally describing no or mild pain scored above the mild/moderate cut point on the visual analogue scale, and patients verbally describing moderate or severe pain scored below the mild/moderate cut point on the visual analogue scale. Using 30 and 60 mm cut points, 1533 observations (12%) showed a category disagreement and using 35 and 80 mm cut points, 1632 (13%) showed a category disagreement. Around 1 in 8 simultaneous pain scores implausibly disagreed, possibly resulting in incorrect pain reporting. The reasons are not known but low rates of literacy and numeracy may be contributing factors. Understanding these disagreements between pain scales is important for pain research and medical practice.

Whole genome and transcriptome analysis enhances precision cancer treatment options

BACKGROUND

Recent advances are enabling delivery of precision genomic medicine to cancer clinics. While the majority of approaches profile panels of selected genes or hotspot regions, comprehensive data provided by whole genome and transcriptome sequencing and analysis (WGTA) presents an opportunity to align a much larger proportion of patients to therapies.

PATIENTS AND METHODS

Samples from 570 patients with advanced or metastatic cancer of diverse types enrolled in the Personalized OncoGenomics (POG) program underwent WGTA. DNA-based data, including mutations, copy number, and mutation signatures, were combined with RNA-based data, including gene expression and fusions, to generate comprehensive WGTA profiles. A multidisciplinary molecular tumour board used WGTA profiles to identify and prioritize clinically actionable alterations and inform therapy. Patient responses to WGTA-informed therapies were collected.

RESULTS

Clinically actionable targets were identified for 83% of patients, 37% of whom received WGTA-informed treatments. RNA expression data were particularly informative, contributing to 67% of WGTA-informed treatments; 25% of treatments were informed by RNA expression alone. Of a total 248 WGTA-informed treatments, 46% resulted in clinical benefit. RNA expression data were comparable to DNA-based mutation and copy number data in aligning to clinically beneficial treatments. Genome signatures also guided therapeutics including platinum, PARP inhibitors, and immunotherapies. Patients accessed WGTA-informed treatments through clinical trials (19%), off-label use (35%), and as standard therapies (46%) including those which would not otherwise have been the next choice of therapy, demonstrating the utility of genomic information to direct use of chemotherapies as well as targeted therapies.

CONCLUSIONS

Integrating RNA expression and genome data illuminated treatment options that resulted in 46% of treated patients experiencing positive clinical benefit, supporting the use of comprehensive WGTA profiling in clinical cancer care.

CLINICAL TRIAL NUMBER

NCT02155621.

Diabetes Self-Care Behaviors and Barriers to Clinical Care During COVID-19 Pandemic for Marshallese Adults

PURPOSE

The purpose of the study was to explore experiences of Marshallese adults related to diabetes self-care behaviors during the COVID-19 pandemic.

METHODS

A qualitative descriptive design was utilized to understand participants' diabetes self-care behaviors during the pandemic. Nine focus groups with 53 participants were held via videoconference and conducted in English, Marshallese, or a mixture of both languages. A priori codes based on diabetes self-care behaviors provided a framework for analyzing and summarizing participant experiences.

RESULTS

Both increases and decreases in healthy eating and exercise were described, with improvements in health behaviors attributed to health education messaging via social media. Participants reported increased stress and difficulty monitoring and managing glucose. Difficulty obtaining medication and difficulty seeing their health care provider regularly was reported and attributed to health care provider availability and lack of insurance due to job loss.

CONCLUSIONS

The study provides significant insight into the reach of health education campaigns via social media and provides important information about the reasons for delays in care, which extend beyond fear of contracting COVID-19 to structural issues.

Trusted Sources of COVID-19 Vaccine Information among Hesitant Adopters in the United States

The World Health Organization has identified vaccine hesitancy as a top health concern. Emerging research shows that those who are hesitant may still get vaccinated; however, little is known about those who say they are hesitant but still get vaccinated. Most people have high trust in several sources of COVID-19 information, and trust in certain information sources such as the Centers for Disease Control and Prevention and health care providers was associated with being vaccinated. This study explored trusted information sources among hesitant adopters in the United States with a survey respondents completed while waiting after receiving a COVID-19 vaccine dose. The study included (n = 867) respondents. The majority of respondents were female (60.21%); were between the ages of 18 and 44 years old (71.97%); and were diverse, with most identifying as White (44.54%) or Hispanic/Latinx (32.55%). Hesitant adopters reported multiple trusted sources of COVID-19 vaccine information, which can be grouped into four emergent subthemes: (1) Health care/Medical science, (2) Personal relationships, (3) News and social media, and (4) Individual/Myself. Some respondents expressed a distrust of all sources of COVID-19 vaccine information, despite receiving the vaccine, describing a lack of trust in traditional sources of information such as the mainstream media or government. This study contributes to the literature by documenting trusted sources of COVID-19 vaccine information among hesitant adopters in the United States. Findings provide important insights about respondents' trusted sources of COVID-19 vaccine information that can inform future public health messaging campaigns intended to increase vaccine uptake among hesitant adopters.

Successful targeting of the NRG1 pathway indicates novel treatment strategy for metastatic cancer

Background

NRG1 fusion-positive lung cancers have emerged as potentially actionable events in lung cancer, but clinical support is currently limited and no evidence of efficacy of this approach in cancers beyond lung has been shown.

Patients and methods

Here, we describe two patients with advanced cancers refractory to standard therapies. Patient 1 had lung adenocarcinoma and patient 2 cholangiocarcinoma. Whole-genome and transcriptome sequencing were carried out for these cases with select findings validated by fluorescence in situ hybridization.

Results

Both tumors were found to be positive for NRG1 gene fusions. In patient 1, an SDC4-NRG1 gene fusion was detected, similar gene fusions having been described in lung cancers previously. In patient 2, a novel ATP1B1-NRG1 gene fusion was detected. Cholangiocarcinoma is not a disease type in which NRG1 fusions had been described previously. Integrative genome analysis was used to assess the potential functional significance of the detected genomic events including the gene fusions, prioritizing therapeutic strategies targeting the HER-family of growth factor receptors. Both patients were treated with the pan HER-family kinase inhibitor afatinib and both displayed significant and durable response to treatment. Upon progression sites of disease were sequenced. The lack of obvious genomic events to describe the disease progression indicated that broad transcriptomic or epigenetic mechanisms could be attributed to the lack of prolonged response to afatinib.

Conclusion

These observations lend further support to the use of pan HER-tyrosine kinase inhibitors for the treatment of NRG1 fusion-positive in both cancers of lung and hepatocellular origin and indicate more broadly that cancers found to be NRG1 fusion-positive may benefit from such a clinical approach regardless of their site of origin.

Clinical trial information

Personalized Oncogenomics (POG) Program of British Columbia: Utilization of Genomic Analysis to Better Understand Tumour Heterogeneity and Evolution (NCT02155621).

Correction to: Dexketoprofen/tramadol 25 mg/75 mg: randomised double-blind trial in moderate-to-severe acute pain after abdominal hysterectomy

CORRECTION

Following publication of the original article [1], the authors reported that additional file 10 contained a typing error in the table "Percentage of responders (≥50% max TOTPAR) over two, four, six and eight hours (single-dose phase) (ITT Population)". The table is to be read as follows.

Randomized clinical trial of dexketoprofen/tramadol 25 mg/75 mg in moderate-to-severe pain after total hip arthroplasty

Background. The aim was to evaluate the analgesic efficacy and safety of the dexketoprofen/tramadol 25 mg/75 mg fixed-dose combination vs dexketoprofen (25 mg) and tramadol (100 mg) in moderate-to-severe acute pain after total hip arthroplasty.

Methods. This was a randomized, double-blind, parallel-group study in patients experiencing pain of at least moderate intensity on the day after surgery, compared with placebo at first administration to validate the pain model. The study drug was administered orally every 8 h throughout a 5 day period. Rescue medication, metamizole 500 mg, was available during the treatment period. The evaluation of efficacy was based on patient assessments of pain intensity and pain relief. The primary end point was the mean sum of the pain intensity difference values throughout the first 8 h (SPID₈).

Results. Overall, 641 patients, mean age 62 (range 29–80) yr, were analysed; mean (sd) values of SPID₈ were 247 (157) for dexketoprofen/tramadol, 209 (155) for dexketoprofen, 205 (146) for tramadol, and 151 (159) for placebo. The primary analysis confirmed the superiority of the combination over dexketoprofen 25 mg (P=0.019; 95% confidence interval 6.4–73) and tramadol 100 mg (P=0.012; 95% confidence interval 9.5–76). The single components were superior to placebo (P<0.05), confirming model sensitivity. Most secondary analyses supported the superiority of the combination. The incidence of adverse drug reactions was low and similar among active treatment groups.

Conclusion. The efficacy results confirmed the superiority of dexketoprofen/tramadol over its single components, even at higher doses (tramadol), with a safety profile fully in line with that previously known for these agents in monotherapy.

Clinical trial registration. EudraCT 2012-004548-31 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=eudract_number:2012-004548-31);

ClinicalTrials.gov NCT01902134 (https://www.clinicaltrials.gov/ct2/show/NCT01902134?term=NCT01902134&rank=1).

Dexketoprofen/tramadol 25 mg/75 mg: randomised double-blind trial in moderate-to-severe acute pain after abdominal hysterectomy

BACKGROUND

Dexketoprofen trometamol plus tramadol hydrochloride is a new oral combination of two analgesics, which have different mechanisms of action for the treatment of moderate to severe acute pain.

METHODS

Randomised, double-blind, parallel, placebo and active-controlled, single and multiple-dose study to evaluate the analgesic efficacy and safety of dexketoprofen/tramadol 25 mg/75 mg in comparison with the single agents (dexketoprofen 25 mg and tramadol 100 mg) in moderate to severe acute pain after abdominal hysterectomy. Patients received seven consecutive doses of study drug within a 3-day period, each dose separated by an 8-hour interval. A placebo arm was included during the single-dose phase to validate the pain model. Efficacy assessments included pain intensity, pain relief, patient global evaluation and use of rescue medication. The primary endpoint was the mean sum of pain intensity differences over the first 8 h (SPID8).

RESULTS

The efficacy analysis included 606 patients, with a mean age of 48 years (range 25-73). The study results confirmed the superiority of the combination over the single agents in terms of the primary endpoint (p <0.001). Secondary endpoints were generally supportive of the superiority of the combination for both single and multiple doses. Most common adverse drug reactions (ADRs) were nausea (4.6%) and vomiting (2.3%). All other ADRs were experienced by less than 2% of patients.

CONCLUSIONS

The study results provided robust evidence of the superiority of dexketoprofen/tramadol 25 mg/75 mg over the single components in the management of moderate to severe acute pain, as confirmed by the single-dose efficacy, repeated-dose sustained effect and good safety profile observed.

TRIAL REGISTRATION

EU Clinical Trials Register (EudraCT number 2012-004545-32, registered 04 October 2012); Clinicaltrials.gov ( NCT01904149, registered 17 July 2013).

Speed, science and optimal pain relief

Pain is a major global health problem. Six of the 11 most prevalent conditions worldwide are pain-related, with tension-type headache and migraine being the second and third most prevalent conditions. Pain also ranks high among the conditions that have the longest-lasting impact: five of the top 11 contributors to years lived with disability are pain-related.

Validating speed of onset as a key component of good analgesic response in acute pain

Background

Previous analysis of a single data set in acute pain following third molar extraction demonstrated a strong relationship between the speed of reduction of pain intensity and overall pain relief, as well as need for additional analgesia.

Methods

Individual patient data analysis of a single randomized, double-blind trial of placebo, paracetamol 1000 mg, ibuprofen sodium 400 mg and ibuprofen-poloxamer 400 mg following third molar extraction. Visual analogue scale pain intensity (VASPI) and other measurements were made at baseline, every 5–45 min, and at 60, 90, 120, 180, 240, 300 and 360 min.

Results

Most patients produced consistent VASPI results over time. For placebo and paracetamol, few patients achieved low VASPI scores and maintained them. For both ibuprofen formulations, VASPI scores fell rapidly during the first hour and were then typically maintained until later re-medication. Analysis of all patients showed that rapid VASPI reduction in the first hour was strongly correlated with good overall pain relief (high total pain relief over 0–6 h), and with lesser need for additional analgesia within 6 h. Results for this analysis were in very good agreement with a previous analysis, validating the relationship between fast initial pain intensity reduction and overall good pain relief in this setting.

Conclusions

In acute pain following third molar extraction, faster acting analgesic formulations provide earlier onset of pain relief, better overall pain relief and a less frequent need for additional analgesia, indicating longer lasting pain relief.

Challenges in design and interpretation of chronic pain trials

The process of systematic review has shone a light on the methodology of randomized controlled trials. Notably, a range of potential biases hinders the interpretation of chronic pain trials. These include a consistent bias favouring active over placebo in trials that are small and of short duration. The use of the 'last observation carried forward' imputation method is known to inflate results, often generating statistically significance when adverse event withdrawals are high; in clinical practice terms, this is the wrong answer. Patients want outcomes of low pain scores, large reductions in pain and relief from associated symptoms, with improvements in ability to function and in quality of life. Some patients achieve this, but many do not. The distribution of benefit is skewed and the use of average pain scores, or change in pain, can be misleading compared with responder analysis in which withdrawal is regarded as non-response. Historically, chronic pain trials have had a simple classic or a crossover design. They have been small and short, and used inappropriate imputation and outcomes unconnected to the experiences of most patients. While these designs are useful for answering some questions, they may be insensitive for many interventions. Newer designs, like enriched enrolment randomized withdrawal (EERW) trials or clinical effectiveness trials, are potentially more interesting and informative.

Duloxetine use in chronic painful conditions--individual patient data responder analysis

Background

Duloxetine has been studied in four distinct chronic pain conditions – osteoarthritis (OA), fibromyalgia, chronic low back pain (CLBP) and diabetic peripheral neuropathic pain (DPNP). These trials have involved large numbers of patients with at least moderate pain, and have used similar methods for recording pain intensity, over about 12 weeks.

Methods

Data from the trials were pooled according to painful condition, and reanalysed at the level of the individual patient and using increasing levels of pain intensity reduction (<15%, 15–29%, 30–49%, ≥50%), with different imputation methods on withdrawal.

Results

The proportion of patients recording at least 50% pain intensity reduction plateaued after 2–6 weeks in fibromyalgia, and 8–12 weeks in other conditions. The duloxetine-specific benefit [number needed to treat (NNT) for at least 50% pain intensity reduction] was fairly constant after about 2 weeks for DPNP and fibromyalgia and after about 4 or 5 weeks for OA and CLBP. In all conditions, responses were bimodal, with patients generally experiencing either very good or very poor pain relief. Last-observation-carried-forward imputation produced numerically and occasionally statistically better (lower) NNTs than use of baseline-observation-carried-forward (true response).

Conclusions

Baseline-observation-carried-forward (true response), which combines the success of high levels of pain relief with the failure to experience pain relief on withdrawal of the drug is conservative and probably reflective of clinical practice experience. The distribution of effect was not normal; few patients had the average response and averages are not an appropriate descriptor for these data.

What's already known about this topic?

What does this study add?

End-to-end military pain management

The last three years have seen significant changes in the Defence Medical Services approach to trauma pain management. This article seeks to outline these changes that have occurred at every level of the casualty's journey along the chain of evacuation, from the point of injury to rehabilitation and either continued employment in the Services or to medical discharge. Particular attention is paid to the evidence for the interventions used for both acute pain and chronic pain management. Also highlighted are possible differences in pain management techniques between civilian and military casualties.

THE PHYSIOLOGICAL RESPONSE OF PROSTATIC AND VESICULAR TRANSPLANTS IN THE ANTERIOR CHAMBER OF THE EYE

1. With a photographic method for the determination of the size of prostatic and vesicular transplants in the anterior chamber of the eye, it has been possible to follow continuously the response to an injection of a hormone. 2. The results may be briefly summarized as follows: (a) One injection of the gonadotropic substance of pregnancy urine produces a moderate increase in size; (b) subsequent injections of this same substance for a period of at least 3 months are without effect; (c) an alkaline extract of the whole anterior pituitary gland produces a similar increase; (d) all pituitary derivatives are ineffective in the castrated animal; (e) castration brings about a decrease in size that gradually loses velocity; (f) the male sex hormone produces a slight increase in intact, and a variable, at times conspicuous, increase in castrated animals; (g) the female sex hormone provokes a conspicuous increase in both intact and castrated animals; (h) the hormone of the corpus luteum has no effect; and (i) there is no evidence of synergism of the pituitary and male sex hormones nor of antagonism of the male and female sex hormones in adult rabbits.

HISTOLOGICAL STUDIES OF THE BONE MARROW IN FASTED AND POLYNEURITIC PIGEONS

1. The histological changes of the bone marrow in fasted and rice disease pigeons are essentially the same. 2. The histological changes of the bone marrow in pure vitamin B deficiency consist of degeneration and edema and slight endothelial proliferation of the small vascular channels, but with active hematopoiesis. 3. The anemia of rice disease in pigeons is in large part a starvation anemia and not directly related to vitamin B deficiency.

NUMBER OF GLOMERULI IN KIDNEY OF ADULT WHITE RAT UNILATERALLY NEPHRECTOMIZED IN EARLY LIFE

Unilateral nephrectomy during the period of active nephrogenesis in the white rat has no effect on the total number of glomeruli which will be formed in the opposite kidney.

VARIATION IN THE SIZE OF TRANSPLANTS OF THE PROSTATE AND SEMINAL VESICLE IN THE ANTERIOR CHAMBER OF THE EYE

1. A method is described with which the two-dimensional size of a transplant in the anterior chamber of the eye may be measured daily with a high degree of accuracy. 2. The size of transplants of the prostate and seminal vesicles varies from day to day and objective evidence indicates that this variation is related to physiologically active testicular tissue.

THE EFFECT OF UNILATERAL NEPHRECTOMY ON THE TOTAL NUMBER OF OPEN GLOMERULI IN THE RABBIT

1. Under the experimental conditions employed, from 44 to 78 per cent of the glomeruli of the normal rabbit kidney contain circulating blood at any one moment. 2. After unilateral nephrectomy the number of glomeruli in the remaining kidney, which contain circulating blood, is increased to 91 to 99 per cent. 3. Compensation for the removal of one kidney is accomplished during the first 10 days at least, by an increase of the number of open glomeruli in the opposite kidney.

THE EFFECT OF UNILATERAL NEPHRECTOMY ON THE SENILE ATROPHY OF THE KIDNEY IN THE WHITE RAT

1. In senility in the white rat there is a decrease in the total number of glomerular units. 2, The decrease in glomerular units is associated with an increase in the average diameter and a greater variation in size, of the remaining glomeruli. 3. Unilateral nephrectomy during adult life has no effect on these senile changes.

THE EFFECT OF AVITAMINOSIS-A ON THE PROSTATE

1. Vitamin A deficiency alone in the white rat is associated with atrophy of the testis and accessory sexual glands. This would appear to be indicative of some disturbance in the hypophyseal-gonadalprostatic hormonal relationships. All of the known vitamins necessary for the rat, except vitamin A, were present in the diet fed the animals studied. 2. Vitamin A deficiency in the rat is associated with foci of inflammation and epithelial metaplasia in the prostatic acini and vesicular ducts entirely similar to that reported in other organs. 3. Focal metaplasia and inflammation is occasionally encountered in the prostate of patients with extreme inanition associated with stenosis of the esophagus. It seems probable that this lesion is due to vitamin A deficiency.

Responder analysis for pain relief and numbers needed to treat in a meta-analysis of etoricoxib osteoarthritis trials: bridging a gap between clinical trials and clinical practice

BACKGROUND

Population mean changes from clinical trials are difficult to apply to individuals in clinical practice. Responder analysis may be better, but needs validating for level of response and treatment duration.

METHODS

The numbers of patients with pain relief over baseline (> or =15%, > or =30%, > or =50%, > or =70%) at 2, 4, 8 and 12 weeks of treatment were obtained using the WOMAC 100 mm visual analogue pain subscale score for each treatment group in seven randomised placebo-controlled trials of etoricoxib in osteoarthritis lasting > or =6 weeks. Dropouts were assigned 0% improvement from baseline from then on. The numbers needed to treat (NNTs) were calculated at each level of response and time point.

RESULTS

3554 patients were treated with placebo, etoricoxib 30 mg and 60 mg, celecoxib 200 mg, naproxen 1000 mg or ibuprofen 2400 mg daily. Response rates fell with increasing pain relief: 60-80% experienced minimally important pain relief (> or =15%), 50-60% moderate pain relief (> or =30%), 40-50% substantial pain relief (> or =50%) and 20-30% extensive pain relief (> or =70%). NNTs for etoricoxib, celecoxib and naproxen were stable over 2-12 weeks. Ibuprofen showed lessening of effectiveness with time.

CONCLUSION

Responder rates and NNTs are reproducible for different levels of response over 12 weeks and have relevance for clinical practice at the individual patient level. An average 10 mm improvement in pain equates to almost one in two patients having substantial benefit.

Analysis of individual patient data from clinical trials: epidural morphine for postoperative pain

BACKGROUND

Individual patient information from clinical trials is infrequently available, but can provide insights for clinical trials and practice.

METHODS

We analysed individual patient information from five randomized trials (913 patients) of i.v. patient-controlled analgesia (IVPCA) plus epidural placebo, morphine sulphate (MS) 5 mg, or extended-release epidural morphine (EREM; DepoDur) at doses of 5-30 mg, to explore effects of a range of epidural morphine doses. Pain and opioid requirement on first and second postoperative days, dose-response, clinically relevant comparisons of IVPCA without epidural morphine, 5 mg MS, and 10 mg EREM, and relationship between patient rating and other measures were described.

RESULTS

There were three strong findings. Epidural morphine resulted in greater patient satisfaction, despite higher rates of adverse events. Those describing their analgesic medication as 'very good' or 'excellent' used IVPCA opioid less and had pain scores significantly below the global mean, whereas those describing their medication as 'poor' or 'fair' had pain scores significantly above the mean. Epidural morphine meant less need for postoperative IVPCA opioid than epidural placebo. The therapeutic gain with EREM was lower pain scores with less IVPCA opioid. Moderate or severe pruritus was more common with IVPCA plus epidural morphine, whatever the formulation, compared with IVPCA plus placebo.

CONCLUSIONS

Analysis of individual patient data from high-quality clinical trials provides important insights into characteristics of new agents not immediately apparent from original trials, and also informing clinical practice. Prophylactic epidural morphine provides a better patient experience than IVPCA alone.

Single dose oral lumiracoxib for postoperative pain

BACKGROUND

Lumiracoxib is a novel selective cyclooxygenase-2 (COX-2) inhibitor. COX-2 inhibitors have been developed to avoid COX-1 related gastrointestinal (GI) problems. Lumiracoxib has analgesic and anti-inflammatory activity comparable with traditional non-steroidal anti-inflammatory drugs (tNSAIDs) in the management of post-operative pain, but with the advantage of better GI tolerability.

OBJECTIVES

To review the analgesic efficacy, duration of analgesia, and adverse effects of a single oral dose of lumiracoxib for moderate to severe postoperative pain in adults and compare it with established analgesics.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to March 2007), EMBASE (1974 to 2006), and PubMed (February 2007).

SELECTION CRITERIA

Single oral dose, randomised placebo controlled trials of lumiracoxib, in acute postoperative pain, in adult patients.

DATA COLLECTION AND ANALYSIS

Trials were quality scored and data extracted by two review authors independently. Summed pain relief (TOTPAR) was extracted and converted into dichotomous information yielding the number of patients with at least 50% pain relief. These derived results were used to calculate the relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Three studies (737 patients) met the inclusion criteria. In total 211 patients were treated with lumiracoxib 400 mg, 51 with lumiracoxib 100 mg, and 161 with placebo. Active comparators were naproxen 500 mg (60 patients), rofecoxib 50 mg (102), celecoxib 200 mg (101), and ibuprofen 400 mg (51). One hundred patients (48%) given lumiracoxib 400 mg had at least 50% pain relief over six hours, compared with 17 (11%) given placebo; RB 4.8 (95% CI 2.9 to 7.9), NNT 2.7 (2.2 to 3.5). Weighted median time to use of rescue medication was 7.4 hours for lumiracoxib 400 mg and 1.8 hours for placebo. Patient global assessment at study endpoint was rated as "excellent" by 71 patients (34%) given lumiracoxib 400 mg and 5 (3%) given placebo. Median time to onset of analgesia was shorter for lumiracoxib 400 mg (0.6 to 1.5 hours) than placebo (>12 hours), and use of rescue medication within 12 hours occurred in 64 patients (58%) given lumiracoxib 400 mg and 100 (91%) given placebo. Adverse events reported were generally mild to moderate in severity, with one serious adverse event reported in a patient given placebo.

AUTHORS' CONCLUSIONS

Lumiracoxib 400 mg given as a single oral dose, is an effective analgesic for acute postoperative pain.

WITHDRAWN: Rizatriptan for acute migraine

BACKGROUND

There are a number of different drug treatments for acute migraine, including currently four triptans, with several more likely to become available in the future. There is a need for evidence-based information to help determine the balance of benefit and harm for acute migraine treatment.

OBJECTIVES

To quantitatively assess the efficacy of a single dose of rizatriptan (Maxalt) for treating a single migraine attack using the outcomes of headache response and pain-free response at half-an-hour, one hour, two hours, and sustained relief over 24 hours. To express efficacy in terms of numbers-needed-to-treat (NNTs).

SEARCH STRATEGY

Trials were identified by searching MEDLINE (1966-July 2000), EMBASE (1980-June 2000), the Cochrane Library (Issue 3, 2000) and the Oxford Pain Relief Database (1950-1994). Date of last search: July 2000.

SELECTION CRITERIA

The inclusion criteria were randomised, placebo-controlled trials of rizatriptan for acute migraine; double-blind design; International Headache Society diagnostic criteria for migraine with or without aura; single migraine attack; single-dose treatment at standard doses; adult population; baseline pain of moderate or severe intensity using a four-point standardised rating scale; dichotomous or percentage data for at least one of the main efficacy outcomes; and full journal publication.

DATA COLLECTION AND ANALYSIS

Main outcomes considered were i) headache response at two hours, ii) headache response at one hour, iii) pain-free response at two hours, iv) sustained relief over 24 hours, v) pain-free response at 24 hours and vi) adverse effects. Minor outcomes were headache response and pain-free response at half-an-hour and four hours, and pain-free response at one hour. Dichotomous or percentage data were extracted and used to calculate the relative benefit (RB) and number-needed-to-treat (NNT) for each outcome.

MAIN RESULTS

Seven trials met our inclusion criteria, with 2626 patients given rizatriptan and 902 given placebo. Significant benefit of rizatriptan over placebo was shown for both doses of rizatriptan (5 mg and 10 mg) for all five main efficacy outcomes (ranging from one to 24 hours). A dose response was seen for the main outcomes. It was not possible to analyse adverse effects information in a meaningful way.

AUTHORS' CONCLUSIONS

Rizatriptan 5 mg and 10 mg are effective in treating acute migraine, with a dose-related increase in efficacy.

WITHDRAWN: Eletriptan for acute migraine

BACKGROUND

Eletriptan (Relpax) is a new triptan soon to be made available by prescription for the treatment of acute migraine. Currently five triptans are available by prescription and more are under development. In light of the many drugs for treating acute migraine, there is a need for evidence-based assessments to help determine the relative efficacy and harm of these treatments.

OBJECTIVES

To determine the efficacy of eletriptan for treating a single migraine attack using the outcomes of headache response and pain-free response at 0.5, 1, 2 and 4 hours, and sustained relief over 24 hours. To express efficacy in terms of number-needed-to-treat (NNT). To determine the adverse effects of a single dose of eletriptan and express this in terms of number-needed-to-harm (NNH). To allow for the comparison of the efficacy of eletriptan with other migraine treatments evaluated systematically in the same way.

SEARCH STRATEGY

Data from all Phase III randomised placebo-controlled trials were made available by the manufacturer, Pfizer Inc. To date, these trials comprise the only data on eletriptan relevant to this review in a published or unpublished form; thus, searches of electronic databases for further trials of eletriptan were not conducted. Date of last search: January 2000.

SELECTION CRITERIA

Trials of eletriptan for acute migraine; randomised allocation to treatment groups, including a placebo group; double-blind design; International Headache Society diagnostic criteria for migraine with or without aura; single migraine attack; single-dose treatment at standard doses; adult population; baseline pain of moderate or severe intensity using a 4-point standardised rating scale (0 = no pain, 1 = mild pain, 2 = moderate pain and 3 = severe pain); and dichotomous or percentage data for at least one of the main efficacy outcomes.

DATA COLLECTION AND ANALYSIS

Trials were scored for quality and data extracted by two independent reviewers. Dichotomous or percentage data were extracted and pooled to calculate the relative benefit (RB) or relative risk (RR) and NNTs or NNHs for a number of outcomes for eletriptan 20 mg, 40 mg and 80 mg. The main outcomes considered were headache response at 1 and 2 hours, pain-free response at 2 hours, sustained relief over 24 hours and adverse effects. Minor outcomes considered were headache response at 0.5 and 4 hours, and pain-free response at 0.5, 1 and 4 hours.

MAIN RESULTS

Six trials met the inclusion criteria. Significant benefit of eletriptan over placebo was shown for eletriptan 20 mg, 40 mg and 80 mg for the primary efficacy outcomes of headache response and pain-free response at 2 hours. For headache response at 2 hours, the NNTs (with 95% confidence intervals) were 4.4 (3.4 to 6.2), 2.9 (2.6 to 3.3) and 2.6 (2.4 to 3.0) for eletriptan 20 mg, 40 mg and 80 mg, respectively. For pain-free response at 2 hours, the NNTs were 9.9 (6.9 to 18), 4.0 (3.6 to 4.5) and 3.7 (3.4 to 4.2), for eletriptan 20 mg, 40 and 80 mg, respectively. There was no significant difference in the incidence of major adverse effects between any dose of eletriptan and placebo. The incidence of minor adverse effects was significantly higher for all eletriptan doses than for placebo, with NNHs of 11 (95% confidence interval, 6.2 to 39), 7.0 (5.2 to 11) and 3.7 (3.1 to 4.5) for eletriptan 20 mg, 40 mg and 80 mg, respectively.

AUTHORS' CONCLUSIONS

Eletriptan 20 mg, 40 mg and 80 mg are effective for the treatment of an acute migraine attack. Effectiveness is dose-related, with statistically significant differences between doses for pain-free response and 24-hour outcomes. Eletriptan compares well with other triptans available for outcomes measured up to 2 hours and provides meaningful relief for 24 hours. Taken as a single dose, eletriptan was well tolerated and caused no major harm. The incidence of minor harm was dose-dependent, with 80 mg giving significantly more adverse effects than 40 mg.

NSAIDs: a clinical approach to the problems of gastrointestinal side-effects

Despite the fact that non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs in medicine today, 2-10% of patients must discontinue their use primarily due to gastrointestinal (GI) side-effects. While the development of non-aspirin NSAIDs (NA-NSAIDs) has significantly reduced GI side-effects, major problems persist. A practical clinical approach to these problems includes informing the patient about the risks and benefits of NSAIDs, risk management during treatment with NSAIDs and investigation of symptomatic side-effects during treatment. Prophylaxis of GI side-effects is feasible in selected populations, but it has not been studied widely and may not be cost-effective. At present, costs of prophylaxis in all but selected populations with multiple risks probably outweight the benefits.

Systematic review of systematic reviews of acupuncture published 1996-2005

Systematic reviews of acupuncture have tended to support its use, but few applied rigorous inclusion criteria. We tested the credibility of conclusions of systematic reviews of acupuncture published since 1996 by applying rigorous inclusion criteria. Reinterpretation used randomised and double blind trials with valid outcomes or design, and with information available from at least four trials or from 200 patients. Qualified support for acupuncture was originally reported in 12 out of 35 systematic reviews, and strong support was found in another six. Applying stricter inclusion criteria, however, showed that none of the 35 reviews supported acupuncture, predominantly because there were too few patients in the randomised, double blind studies. Six reviews with more than 200 patients in randomised, double blind studies had good evidence of no benefit. Systematic reviews of acupuncture have overstated effectiveness by including studies likely to be biased. They provide no robust evidence that acupuncture works for any indication.

Perioperative ketamine for acute postoperative pain

BACKGROUND

Postoperative pain management is often limited by adverse effects such as nausea and vomiting. Adjuvant treatment with an inexpensive opioid-sparing drug such as ketamine may be of value in giving better analgesia with fewer adverse effects.

OBJECTIVES

To evaluate the effectiveness and tolerability of ketamine administered perioperatively in the treatment of acute postoperative pain in adults.

SEARCH STRATEGY

Studies were identified from MEDLINE (1966-2004), EMBASE (1980-2004), the Cochrane Library (2004) and by handsearching reference lists from review articles and trials. The manufacturer of ketamine (Pfizer) provided search results from their in-house database, PARDLARS.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of adult patients undergoing surgery, being treated with perioperative ketamine or placebo. Studies where ketamine was administered in addition to a basic analgesic (such as morphine or NSAID) in one study group, and compared with a group receiving the same basic analgesic (but without ketamine) in another group, were also included.

DATA COLLECTION AND ANALYSIS

Two independent reviewers identified fifty five RCTs for potential inclusion. Quality and validity assessment was performed by two independent reviewers. In the case of discrepancy, a third reviewer was consulted. Patient reported pain intensity and pain relief was assessed using visual analogue scales or verbal rating scales and adverse effects data were collated.

MAIN RESULTS

Thirty-seven trials were included (2240 participants). Eighteen trials were excluded.Twenty-seven of the 37 trials found that perioperative subanaesthetic doses of ketamine reduced rescue analgesic requirements or pain intensity, or both. Quantitative analysis showed that treatment with ketamine reduced 24 hour PCA morphine consumption and postoperative nausea or vomiting (PONV). Adverse effects were mild or absent.

AUTHORS' CONCLUSIONS

Ketamine in subanaesthetic dose (that is a dose which is below that required to produce anaesthesia) is effective in reducing morphine requirements in the first 24 hours after surgery. Ketamine also reduces postoperative nausea and vomiting. Adverse effects are mild or absent.

Peri-operative ketamine for acute post-operative pain: a quantitative and qualitative systematic review (Cochrane review)

BACKGROUND

Post-operative pain management is usually limited by adverse effects such as nausea and vomiting. Adjuvant treatment with an inexpensive opioid-sparing drug such as ketamine may be of value in giving better analgesia with fewer adverse effects. The objective of this systematic review was to evaluate the effectiveness and tolerability of ketamine administered peri-operatively in the treatment of acute post-operative pain in adults.

METHODS

Studies were identified from MEDLINE (1966-2004), EMBASE (1980-2004), the Cochrane Library (2004) and by hand searching reference lists from review articles and trials. The manufacturer of ketamine (Pfizer AS, Lysaker, Norway) provided search results from their in-house database, PARDLARS. Randomized and controlled trials (RCTs) of adult patients undergoing surgery, being treated with peri-operative ketamine, placebo or an active control were considered for inclusion.

RESULTS

Eighteen trials were excluded. Thirty-seven trials were included. Twenty-seven out of 37 trials found that peri-operative ketamine reduced rescue analgesic requirements or pain intensity, or both. Quantitative analysis showed that treatment with ketamine reduced 24-h patient-controlled analgesia (PCA) morphine consumption and post-operative nausea and vomiting (PONV). Adverse effects were mild or absent.

CONCLUSION

In the first 24 h after surgery, ketamine reduces morphine requirements. Ketamine also reduces PONV. Adverse effects are mild or absent. These data should be interpreted with caution as the retrieved studies were heterogenous and the result of the meta-analysis can not be translated into any specific administration regimen with ketamine.

Acute pain: individual patient meta-analysis shows the impact of different ways of analysing and presenting results

Individual patient meta-analysis using information from clinically homogeneous acute pain trials with observations over 24h was used to investigate different ways trials can be analysed and reported. There were 13 third-molar extraction trials, with 1,330 patients using rofecoxib 50mg, 303 using ibuprofen 400mg, and 570 using placebo. Pain relief scores were available at individual time points, plus time to remedication. Many more patients remedicated with placebo than ibuprofen 400mg, and more with ibuprofen than rofecoxib 50mg. Median time to remedication, the proportion remedicated at various times, or survival curves would be useful outcomes. In dealing with missing data points when patients remedicated, baseline observation carried forward was more conservative than last observation carried forward, resulting in higher (worse) NNTs and lower average pain scores after 12 and 24h. Results based on both methods might be sensible for trials longer than eight hours. The distribution of pain relief was highly skewed, especially at later times, when almost no patient was average. Different cut points for pain relief (at least 25, 50 or 75% maxTOTPAR) and longer duration changed the NNT for ibuprofen compared with placebo, but less for rofecoxib, reflecting longer duration of action of rofecoxib. Reporting for each treatment group the percentage of patients with 25, 50 and 75% pain relief at various times after dose, and reporting the proportion of patients with good or complete pain relief, and inadequate pain relief, at each time point, would improve acute pain trial reporting.

Carbamazepine for acute and chronic pain

BACKGROUND

Anticonvulsant drugs have been used in the management of pain since the 1960s. The clinical impression is that they are useful for chronic neuropathic pain, especially when the pain is lancinating or burning.

OBJECTIVES

To evaluate the analgesic effectiveness and adverse effects of the anticonvulsant medicine carbamazepine for pain management in clinical practice and to identify a clinical research agenda. Migraine and headache studies are not included in this review.

SEARCH STRATEGY

Randomised trials (RCTs) of anticonvulsants in acute, chronic or cancer pain were identified by MEDLINE (1966-2004), EMBASE (1994-2004), SIGLE (1980-2004) and the Cochrane Controlled Trials Register (CENTRAL/CCTR) (Cochrane Library Issue 3, 2003). In addition, 41 medical journals were hand searched for a previous version of this review. Additional reports were identified from the reference list of the retrieved papers, and by contacting investigators. Date of most recent search: November 2004.

SELECTION CRITERIA

Randomised trials reporting the analgesic effects of carbamazepine in patients, with subjective pain assessment as either the primary or a secondary outcome.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent reviewers, and trials were quality scored. Numbers-needed-to-treat (NNTs) were calculated from dichotomous data for effectiveness, adverse effects and drug-related study withdrawal, for individual studies and for pooled data.

MAIN RESULTS

Twelve studies were included (404 participants). Four studies included trigeminal neuralgia patients. Two studies which provided evaluable data yielded an NNT for effectiveness of 1.8 (95%CI 1.4-2.8). For diabetic neuropathy there was insufficient data for an NNT to be calculated.Numbers-needed-to-harm (NNHs) were calculated where possible by combining studies for each drug entity irrespective of the condition treated. The results were, for minor harm, carbamazepine 3.7 (CI 2.4-7.8), NNHs for major harm were not statistically significant for carbamazepine compared with placebo. There is no evidence that carbamazepine is effective for acute pain.

AUTHORS' CONCLUSIONS

There is evidence to show that carbamazepine is effective but trials are small.

Gabapentin for acute and chronic pain

BACKGROUND

Anticonvulsant drugs have been used in the management of pain since the 1960s. The clinical impression is that they are useful for chronic neuropathic pain, especially when the pain is lancinating or burning.

OBJECTIVES

To evaluate the analgesic effectiveness and adverse effects of gabapentin for pain management in clinical practice.

SEARCH STRATEGY

Randomised trials of gabapentin in acute, chronic or cancer pain were identified by MEDLINE (1966-Nov 2004), EMBASE (1994-Nov 2004), SIGLE (1980-Jan 2004) and the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 4, 2004). Additional reports were identified from the reference list of the retrieved papers, and by contacting investigators. Date of most recent search: January 2004.

SELECTION CRITERIA

Randomised trials reporting the analgesic effects of gabapentin in patients, with subjective pain assessment as either the primary or a secondary outcome.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent reviewers, and trials were quality scored. Numbers-needed-to-treat (NNTs) were calculated, where possible, from dichotomous data for effectiveness, adverse effects and drug-related study withdrawal.

MAIN RESULTS

Fourteen reports describing 15 studies of gabapentin were considered eligible (1468 participants). One was a study of acute pain. The remainder included the following conditions: post-herpetic neuralgia (two studies), diabetic neuropathy (seven studies), a cancer related neuropathic pain (one study) phantom limb pain (one study), Guillain Barré syndrome (one study) , spinal chord injury pain (one study) and various neuropathic pains (one study). The study in acute post-operative pain (70 participants) showed no benefit for gabapentin compared to placebo for pain at rest. In chronic pain, the NNT for improvement in all trials with evaluable data is 4.3 (95%CI 3.5-5.7). Forty two percent of participants improved on gabapentin compared to 19% on placebo. The number needed to harm(NNH) for adverse events leading to withdrawal from a trial was not significant. Fourteen percent of participants withdrew from active arms compared to 10% in placebo arms. The NNH for minor harm was 3.7 (95% CI 2.4 to 5.4). The NNT for effective pain relief in diabetic neuropathy was 2.9 (95% CI 2.2 to 4.3) and for post herpetic neuralgia 3.9 (95% CI 3 to 5.7).

AUTHORS' CONCLUSIONS

There is evidence to show that gabapentin is effective in neuropathic pain. There is limited evidence to show that gabapentin is ineffective in acute pain.

Placebo

Placebo, used here to mean an inert treatment given as if it was a real treatment, means lots of different things to different people. The structure of the article is that it begins by talking about the technical use of placebos in clinical trials, and the extent of the placebo response, then about the mechanism--"How does the placebo work?"--and last about the ethics of placebo in the contexts of research and in everyday practice.

Effect of preoperative Cox-II-selective NSAIDs (coxibs) on postoperative outcomes: a systematic review of randomized studies

BACKGROUND

Preoperative use of coxibs has been claimed to reduce postoperative pain and analgesic consumption, and to affect other postoperative outcomes.

METHODS

Systematic review of randomized trials comparing preoperative coxib with preoperative placebo, or active comparator. Searching of PubMed and Cochrane Library to August 2004. A qualitative and a quantitative analysis.

RESULTS

Twenty-two included trials with 2246 patients had high reporting quality and validity scores, though treatment group sizes were small, with a median size of 30 patients. Most trials used oral preoperative rofecoxib (mainly 50 mg) or celecoxib (mainly 200 mg). Preoperative coxibs significantly reduced both postoperative pain and analgesic consumption compared with preoperative placebo in 15/20 trials. In one further trial postoperative pain was reduced and in one analgesic consumption. There was no significant difference in the incidence of postoperative nausea and vomiting in 13/17 studies or when data were pooled. Postoperative antiemetic use was significantly reduced in all five trials reporting it; the NNT to prevent one patient using postoperative antiemetic was 10 (5.5 to 66). No trial reported any significant difference in intraoperative blood loss or recovery from anaesthesia. Patient satisfaction was significantly increased with preoperative coxib use. No conclusions could be drawn from the three trials comparing preoperative coxib with preoperative NSAID. One study reported significantly improved cost-efficacy with rofecoxib.

CONCLUSIONS

Preoperative coxibs had clear benefits in terms of reduced postoperative pain, analgesic consumption and patient satisfaction compared with placebo. Effects on postoperative nausea and vomiting remain uncertain, as do those on recovery from surgery or economic benefit. Future trials should be larger and more pragmatic in nature.

Single dose oral rofecoxib for postoperative pain

BACKGROUND

Editor's note: The anti-inflammatory drug rofecoxib (Vioxx) was withdrawn from the market at the end of September 2004 after it was shown that long-term use (greater than 18 months) could increase the risk of heart attack and stroke. So far, other similar anti-inflammatory drugs are unaffected. Further information is available at www.vioxx.com. Rofecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that was licensed in the UK and the US for acute pain treatment and is associated with fewer gastrointestinal adverse events than conventional NSAIDs. Rofecoxib is believed to be at least as effective as conventional non-steroidal anti-inflammatory drugs (NSAIDs) for postoperative pain.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of rofecoxib for moderate to severe postoperative pain, and to compare its effectiveness with other analgesics used for treating acute pain.

SEARCH STRATEGY

We searched Cochrane Library (Issue 1, 2002), MEDLINE (1966 to March 2002), Biological Abstracts (1985 to Dec 2001), CINAHL (1982 to Dec 2001), Psychinfo (1967 to Jan 2002), PubMed (March 2001) and the Oxford pain database.

SELECTION CRITERIA

Randomised controlled trials of adult patients who received either rofecoxib or placebo for postoperative pain.

DATA COLLECTION AND ANALYSIS

Trials were quality scored and the data extracted by two reviewers independently. Summed pain relief (TOTPAR) or pain intensity difference (SPID) was extracted and converted into dichotomous information yielding the number of patients with at least 50% pain relief. These derived results were used to calculate the relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Seven studies met the inclusion criteria. All the trials were funded by Merck & Company, the manufacturer of rofecoxib. In total, 667 patients were treated with rofecoxib 50 mg and 315 with placebo. The NNT for rofecoxib 50 mg was 2.2 (95% CI 1.9 to 2.4), ie, for every two patients treated with rofecoxib 50 mg, one patient experienced at least 50% pain relief that would not have done had they received placebo. All the studies were of short duration, and reported adverse events occurred less frequently with rofecoxib 50 mg than with placebo.

AUTHORS' CONCLUSIONS

Rofecoxib 50 mg (a dose 2 to 4 times the standard daily dose for chronic pain) is an effective single dose oral analgesic for acute postoperative pain.

Species barriers in prion diseases--brief review

Transmissible spongiform encephalopathies (TSEs or prion diseases) are neurological disorders associated with the aggregation of a pathologic isoform of a host-encoded protein, termed prion protein (PrP). The pathologic isoform of PrP, termed PrP(Sc), is a major constituent of the infectious agent. TSE diseases are characterized by neurodegenerative failure and inevitable morbidity. Bovine spongiform encephalopathy (BSE) has been transmitted from cattle to humans to cause a new variant of Creutzfeldt-Jakob syndrome. The potential for chronic wasting disease to similarly cross the species barrier from cervids to humans is considered unlikely but possible. Thus, understanding how TSE agents overcome resistance to transmission between species is crucial if we are to prevent future epidemics. The species barrier usually can be abrogated to varying degrees in laboratory animals. Studies done with transgenic animals, tissue culture, and cell-free assays established PrP as being necessary for TSE pathogenesis and illustrated that certain amino acid residues are more influential than others for conferring resistance to TSE agent transmission. The essence of what constitutes a TSE agent's species compatibility is thought to be orchestrated by a complex interplay of contributions from its primary amino acid sequence, its glycoform patterns, and its three-dimensional structure.

Single dose oral naproxen and naproxen sodium for acute postoperative pain

BACKGROUND

Postoperative pain is often poorly managed. Treatment options include a range of drug therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) of which naproxen is one. Naproxen is used to treat a variety of painful conditions including acute postoperative pain, and is often combined with sodium to improve its solubility for oral administration. Naproxen sodium 550 mg (equivalent to 500 mg of naproxen) is considered to be an effective dose for treating postoperative pain but to date no systematic review of the effectiveness of naproxen/naproxen sodium at different doses has been published.

OBJECTIVES

To assess the efficacy, safety and duration of action of a single oral dose of naproxen or naproxen sodium for acute postoperative pain in adults.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE and the Oxford Pain Relief Database for relevant studies. Additional studies were identified from the reference list of retrieved reports. The most recent search was undertaken in July 2004.

SELECTION CRITERIA

Included studies were randomised, double blind, placebo-controlled trials of a single dose of orally administered naproxen or naproxen sodium in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Pain relief or pain intensity data were extracted and converted into dichotomous information to give the number of patients with at least 50% pain relief over four to six hours. Relative risk estimates (RR) and the number-needed-to-treat (NNT) for at least 50% pain relief were then calculated. Information was sought on the percentage of patients experiencing any adverse event, and the number-needed-to-harm was derived. Time to remedication was also estimated.

MAIN RESULTS

Ten trials (996 patients) met the inclusion criteria: nine assessed naproxen sodium; one combined the results from two small trials of naproxen alone. Included studies scored well for methodological quality. Meta-analysis of six trials (500 patients) that compared naproxen sodium 550 mg with placebo gave a RR for at least 50% pain relief over 4 to 6 hours of 4.2 (95% confidence interval (CI) 2.9 to 6.0) and an NNT of 2.6 (95% CI 2.2 to 3.2). Three trials (334 patients) assessed naproxen 400 mg and naproxen sodium 440 mg, giving a RR of 4.8 (95% CI 2.75 to 8.38). Two small studies indicated that naproxen 200 mg and naproxen sodium 220 mg may provide effective postoperative pain relief. There was no significant difference between the number of patients experiencing any adverse event on treatment compared with placebo. Weighted mean time to remedication for naproxen sodium 550 mg was 7.6 hours compared with 2.6 hours for placebo.

REVIEWERS' CONCLUSIONS

Naproxen sodium 550 mg, naproxen 400 mg and naproxen sodium 440 mg administered orally are effective analgesics for the treatment of acute postoperative pain in adults. A low incidence of adverse events was found but reporting was not consistent.

Relative efficacy of oral analgesics after third molar extraction

OBJECTIVES

To compare the relative efficacy of analgesics after third molar extraction from systematic reviews of randomised, double blind studies.

DATA SOURCES

Dental trials from systematic reviews of randomised, double-blind studies of analgesics in acute pain.

DATA SELECTION

Number of patients with moderate or severe pain achieving at least half pain relief over 4 to 6 hours after a single oral dose of analgesic.

DATA EXTRACTION

Independently by two reviewers.

DATA SYNTHESIS

Use of dichotomous information from active and placebo treatments, first to calculate the statistical significance using relative risk, and then to evaluate the clinical relevance using number needed to treat (NNT). Non-steroidal anti-inflammatory drugs (NSAIDs) and cyclo-oxygenase-2 (COX-2) inhibitors had the lowest (best) NNTs for the outcome of at least half pain relief over 4-6 hours compared with placebo. With the best performing analgesics, 50-70 patients out of 100 had good pain relief compared with about 10 out of 100 with placebo. Only paracetamol 600/650 mg plus codeine 60 mg was associated with any significant increase in any patient experiencing an adverse event.

CONCLUSIONS

NSAIDs and COX-2 inhibitors have the lowest (best) NNTs. They may also have fewer adverse effects after third molar surgery, though conclusive evidence is lacking. At least 80% of analgesic prescribing by UK dentists is in line with the best available evidence on efficacy and safety.

Composition and stress analysis in Si structures using micro-raman spectroscopy

Strained silicon (Si) technology enables improvements in complementary metal oxide semiconductor (CMOS) performance and functionality via replacement of the bulk, cubic-crystal Si substrate with an Si substrate that contains a tetragonally distorted, biaxially strained Si thin film at the surface. Here we use Raman spectroscopy to allow us to characterise growth processes of strained si, and to characterise the resulting level of strain/stress in the si and the effect it has on the underlying layer of graded SiGe.

Single dose oral diclofenac for postoperative pain

BACKGROUND

Diclofenac is a benzene-acetic acid derivative that acts, like other NSAIDs, by inhibiting cyclo-oxygenase isoforms that mediate the body's production of the prostaglandins implicated in pain and inflammation. Diclofenac is widely available as a sodium or potassium salt. Diclofenac potassium tablets are known as 'immediate-release' diclofenac as absorption takes place in the gastrointestinal tract whereas 'delayed-release' (enteric-coated) diclofenac tablets resist dissolution until reaching the duodenum. An existing review showed that diclofenac was an effective treatment for acute postoperative pain but did not address the distinction between potassium and sodium salts due to lack of data. The aim of this update is to gather and add appropriate information published subsequently and, data permitting, examine any potential differences between the two different diclofenac formulations.

OBJECTIVES

To assess single dose oral diclofenac for the treatment of acute postoperative pain and determine whether there are differences between the different formulations.

SEARCH STRATEGY

We searched the Cochrane Library (Issue 2, 2003), MEDLINE (1966 to May 1996), EMBASE (1980 to 1996), Biological Abstracts (1985 to 2003), the Oxford Pain Relief Database (1950 to 1994), PubMed (1996 to 2003) and reference lists of articles.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac sodium or diclofenac potassium for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trials for inclusion in the review, quality and extracted data. The area under the pain relief versus time curve was used to derive the proportion of patients prescribed diclofenac or placebo with at least 50% pain relief over four to six hours using validated equations. The number needed to treat (NNT) was calculated. Information on adverse effects was also collected.

MAIN RESULTS

One additional trial was included and added to the six trials included in the original review. All seven trials provided data for quantitative analysis: 581 patients were treated with diclofenac and 364 were treated with placebo. The NNT for at least 50% relief over four to six hours with diclofenac 25 mg, 50 mg and 100 mg compared with placebo was 2.8 (95% CI 2.1 to 4.3), 2.3 (2.0 to 2.7) and 1.9 (1.6 to 2.2) respectively. Though higher doses produced lower (better) NNTs, statistical significance was not achieved. There was no significant difference between diclofenac 50 mg and placebo in the proportion of patients experiencing dizziness, headache, nausea or vomiting. The weighted median duration of analgesia was 2 hours for placebo, 6.7 hours for diclofenac 50 mg and 7.2 hours for diclofenac 100 mg. Sensitivity analyses for drug formulation, pain model, trial size and quality did not reveal any statistically significant differences.

REVIEWERS' CONCLUSIONS

Oral diclofenac is an effective single-dose treatment for moderate to severe postoperative pain. There was no significant difference between diclofenac and placebo in the incidence of adverse effects, or between diclofenac sodium and potassium, different pain models, smaller and larger trials and trials of higher and lower quality.

Single dose oral rofecoxib for postoperative pain

BACKGROUND

Rofecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor licensed in the UK and the US for acute pain treatment and is associated with fewer gastrointestinal adverse events than conventional NSAIDs. Rofecoxib is believed to be at least as effective as conventional non-steroidal anti-inflammatory drugs (NSAIDs) for postoperative pain.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of rofecoxib for moderate to severe postoperative pain, and to compare its effectiveness with other analgesics used for treating acute pain.

SEARCH STRATEGY

We searched Cochrane Library (Issue 1, 2002), MEDLINE (1966 to March 2002), Biological Abstracts (1985 to Dec 2001), CINAHL (1982 to Dec 2001), Psychinfo (1967 to Jan 2002), PubMed (March 2001) and the Oxford pain database.

SELECTION CRITERIA

Randomised controlled trials of adult patients who received either rofecoxib or placebo for postoperative pain.

DATA COLLECTION AND ANALYSIS

Trials were quality scored and the data extracted by two reviewers independently. Summed pain relief (TOTPAR) or pain intensity difference (SPID) was extracted and converted into dichotomous information yielding the number of patients with at least 50% pain relief. These derived results were used to calculate the relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Seven studies met the inclusion criteria. All the trials were funded by Merck & Company, the manufacturer of rofecoxib. In total, 667 patients were treated with rofecoxib 50 mg and 315 with placebo. The NNT for rofecoxib 50 mg was 2.2 (95% CI 1.9 to 2.4), ie, for every two patients treated with rofecoxib 50 mg, one patient experienced at least 50% pain relief that would not have done had they received placebo. All the studies were of short duration, and reported adverse events occurred less frequently with rofecoxib 50 mg than with placebo.

REVIEWER'S CONCLUSIONS

Rofecoxib 50 mg (a dose 2 to 4 times the standard daily dose for chronic pain) is an effective single dose oral analgesic for acute postoperative pain.

Benefits of laparoscopy in middle-aged patients

BACKGROUND

The introduction of laparoscopic techniques in biliary, adrenal and thoracic surgery has shortened the patient's hospital stay and lowered costs. However, in colorectal surgery, only a limited number of patients obtain these benefits, and these controversial results have been achieved in laparoscopic appendectomy (LA). The objective of this study was to compare the results of LA performed in young patients (<50 years) to those obtained with older counterparts.

METHODS

All patients who underwent LA and open appendectomy (OA) between January 1996 and December 2000 were analyzed retrospectively. The data included age, gender, American Society of Anesthesiologists (ASA) score, emergent procedure, length of procedure, operating room and hospitalization costs as well as length of stay. For analysis purposes, the patients were divided into two chronological groups: age <50 and age >50 years.

RESULTS

A total of 405 patients were available for analysis. Average age was 35 years and 42% were females. Thirty-nine patients underwent LA. The rate of LA was 14% in women and 6% in men (p<0.05). For young patients, there was no difference between LA and OA in ASA score, length of procedure, operating room costs, and total cost. Length of stay was 2.7 days in both the LA and the OA groups (P>0.05). However, patients >50 years in the LA group had a significantly shorter length of stay (2.5 days) than those in compared to the OA group (6 days) (p<0.05). Furthermore, total hospitalization cost was significantly lower for the LA group (13,448 dollars) than for the OA group (21,730 dollars) (p<0.05). No difference was found for length of operation, ASA score, or operating room costs.

CONCLUSIONS

We found no benefits in terms of cost containment or reduced length of stay for LA patients aged <or=50 years. However, there was a significant decrease in overall costs for LA patients >50 years old. We attribute this diminution of the benefits of LA in younger patients probably diminished due to their lower rate of comorbid conditions and better tolerance of surgical stress.

Single dose oral celecoxib for postoperative pain

BACKGROUND

Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor prescribed for the relief of chronic pain in osteoarthritis and rheumatoid arthritis. The drug is believed to be associated with fewer adverse effects than conventional non-steroidal anti-inflammatory drugs (NSAIDs). However, the effectiveness of celecoxib in the treatment of acute pain has not yet been assessed by systematic review.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of celecoxib for moderate to severe postoperative pain.

SEARCH STRATEGY

We searched the Cochrane Library Controlled Trials Register, MEDLINE, Biological Abstracts, PubMed and the Oxford Pain database. Date of the most recent search: May 2002.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of adults prescribed any dose of oral celecoxib or placebo for acute postoperative pain were included.

DATA COLLECTION AND ANALYSIS

Two trials (418 subjects) met the inclusion criteria for this review. The trials were assessed for quality and the data extracted by two independent reviewers. Summed pain relief (TOTPAR) or pain intensity difference (SPID) was extracted and converted into dichotomous information yielding the number of patients with at least 50% pain relief over 4-6 hours. These derived results were used to calculate the relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

The number-needed-to-treat for celecoxib 200 mg compared with placebo was 4.5 (CI 3.3 to 7.2). For every 4.5 patients experiencing moderate to severe acute pain treated with celecoxib 200 mg one more will experience at least 50% pain relief that would not have done had they received placebo. The median time to remedication over 24 hours was 5.1 hours with celecoxib 200 mg and 1.5 hours with placebo. Quantitative analysis of adverse effects was not possible but no serious or unexpected adverse effects were reported.

REVIEWER'S CONCLUSIONS

Single dose oral celecoxib is an effective means of postoperative pain relief, similar in efficacy to aspirin 600/650 mg, and paracetamol 1000 mg. The two trials included used celecoxib 200 mg, a dose 50% less than is recommended for acute pain. More trials are needed to estimate efficacy for recommended dose of 400 mg, and to reinforce current findings for 200 mg, and provide data for pooled quantitative estimates of adverse effects.

Absence of canine oral papillomavirus DNA following prophylactic L1 particle-mediated immunotherapeutic delivery vaccination

In the canine oral papillomavirus (COPV) model, following wart regression, COPV DNA was detected by PCR at the challenge site. However, following particle-mediated immunotherapeutic delivery (PMID) of COPV L1 and subsequent challenge, no COPV DNA could be detected. These data support PMID of COPV L1 as a protective vaccine and suggest that PMID of L1 may induce virus clearance.

Sildenafil (Viagra) for male erectile dysfunction: a meta-analysis of clinical trial reports

BACKGROUND

Evaluation of company clinical trial reports could provide information for meta-analysis at the commercial introduction of a new technology.

METHODS

Clinical trial reports of sildenafil for erectile dysfunction from September 1997 were used for meta-analysis of randomised trials (at least four weeks duration) and using fixed or dose optimisation regimens. The main outcome sought was an erection, sufficiently rigid for penetration, followed by successful intercourse, and conducted at home.

RESULTS

Ten randomised controlled trials fulfilled the inclusion criteria (2123 men given sildenafil and 1131 placebo). NNT or NNH were calculated for important efficacy, adverse event and discontinuation outcomes. Dose optimisation led to at least 60% of attempts at sexual intercourse being successful in 49% of men, compared with 11% with placebo; the NNT was 2.7 (95% confidence interval 2.3 to 3.3). For global improvement in erections the NNT was 1.7 (1.6 to 1.9). Treatment-related adverse events occurred in 30% of men on dose optimised sildenafil compared with 11% on placebo; the NNH was 5.4 (4.3 to 7.3). All cause discontinuations were less frequent with sildenafil (10%) than with placebo (20%). Sildenafil dose optimisation gave efficacy equivalent to the highest fixed doses, and adverse events equivalent to the lowest fixed doses.

CONCLUSION

This review of clinical trial reports available at the time of licensing agreed with later reviews that had many more trials and patients. Making reports submitted for marketing approval available publicly would provide better information when it was most needed, and would improve evidence-based introduction of new technologies.