The hidden costs of arthritis treatment and the cost of new therapy--the burden of non-steroidal anti-inflammatory drug gastropathy

Pain is very common throughout the world and is an increasing problem in the ageing population. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely prescribed to treat pain and many are also available without prescription, or over the counter. These drugs are effective painkillers, but they can also have severe adverse effects, particularly on the upper gastrointestinal (GI) tract. Therapeutic decisions should be made using the best available evidence and there is a growing body of evidence showing that the new specific cyclooxygenase-2 (COX-2) inhibitors, or coxibs, are effective pain killers that do not cause GI harm. The risks associated with the use of NSAIDs are substantial, with a 1 in 1200 chance of dying from a major GI adverse effect after 2 months of NSAID therapy. These risks increase with age and are avoidable. The costs associated with the prevention and treatment of NSAID-induced GI adverse effects can more than double the cost of the original therapy and should be included when costing NSAID interventions. Taking these costs into account, the expense of switching from a conventional NSAID to a coxib is relatively modest. Compared with other interventions that society may be willing to consider to prevent one death, such as those for the rail (15 million Pounds) and road (100,000 Pounds) networks in the UK, the cost of preventing one death by switching to a coxib is much lower, with a high estimate being 20,000-30,000 Pounds, which is in line with the accepted benchmarks for the cost-effectiveness of medical interventions.

Single dose dipyrone for acute renal colic pain

BACKGROUND

Renal colic pain is extremely painful and requires immediate treatment with strong analgesics. Dipyrone is the most popular non-opioid first line analgesic in many countries but in others it has been banned (e.g. USA, UK) because of its association with blood dyscrasias such as agranulocytosis. Since dipyrone is used in many countries (e.g. Brazil, Spain) there is a need to determine the benefits and harms of its use to treat renal colic pain.

OBJECTIVES

To assess quantitatively the analgesic efficacy and adverse effects of single-dose dipyrone in adults with moderate to severe renal colic pain.

SEARCH STRATEGY

Published reports were identified from electronic databases (MEDLINE, EMBASE, the Cochrane Library, LILACS) and additional studies were identified from the reference lists of retrieved reports. Date of the most recent search: January 2000.

SELECTION CRITERIA

Inclusion criteria were: full journal publication; RCT with a double-blind design; adult patients with baseline renal colic pain of moderate or severe intensity; treatment arms which included dipyrone (oral, intramuscular or intravenous administration) and a control; single dose data.

DATA COLLECTION AND ANALYSIS

Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief over 15-30 minutes, 1-2 hours and six hours. The proportion of patients with at least 50% pain relief was calculated. Single dose adverse effect data were collected.

MAIN RESULTS

Eleven studies with 1053 patients (550 on dipyrone) met the inclusion criteria. Unfortunately, few data were available for analysis; most analyses were based on the results of single, small trials and statistical pooling of the results was inappropriate. Efficacy estimates were calculated as the weighted mean percent of patients achieving at least 50% pain relief with the range of values from trials contributing to the analysis. However, these estimates were not robust. Commonly reported adverse effects with intravenous dipyrone were dry mouth and somnolence, and one study reported pain at the injection site. Insufficient information was available for safety analyses to be conducted.

REVIEWER'S CONCLUSIONS

Limited available data indicated that single dose dipyrone was of similar efficacy to other analgesics used in renal colic pain, although intramuscular dipyrone was less effective than diclofenac 75 mg. Combining dipyrone with antispasmolytic agents did not appear to improve its efficacy. Intravenous dipyrone was more effective than intramuscular dipyrone. Dry mouth and somnolence were commonly reported with intravenous dipyrone. None of the studies reported agranulocytosis.

Pain and systematic reviews

There is a huge medical literature, with very large amounts of information. Some of that information is useful, some not. The task is to distil the information, apply quality filters, and place it into context so that we can use the knowledge we have with wisdom. The process of systematically reviewing the literature helps us generate solid, unbiased knowledge. Using appropriate tools, like numbers needed to treat (NNT), we can provide a solid basis to allow practitioners and their patients to make the best, and best informed, choices about their care.

Cannabinoids for control of chemotherapy induced nausea and vomiting: quantitative systematic review

OBJECTIVE

To quantify the antiemetic efficacy and adverse effects of cannabis used for sickness induced by chemotherapy.

DESIGN

Systematic review.

DATA SOURCES

Systematic search (Medline, Embase, Cochrane library, bibliographies), any language, to August 2000.

STUDIES

30 randomised comparisons of cannabis with placebo or antiemetics from which dichotomous data on efficacy and harm were available (1366 patients). Oral nabilone, oral dronabinol (tetrahydrocannabinol), and intramuscular levonantradol were tested. No cannabis was smoked. Follow up lasted 24 hours.

RESULTS

Cannabinoids were more effective antiemetics than prochlorperazine, metoclopramide, chlorpromazine, thiethylperazine, haloperidol, domperidone, or alizapride: relative risk 1.38 (95% confidence interval 1.18 to 1.62), number needed to treat 6 for complete control of nausea; 1.28 (1.08 to 1.51), NNT 8 for complete control of vomiting. Cannabinoids were not more effective in patients receiving very low or very high emetogenic chemotherapy. In crossover trials, patients preferred cannabinoids for future chemotherapy cycles: 2.39 (2.05 to 2.78), NNT 3. Some potentially beneficial side effects occurred more often with cannabinoids: "high" 10.6 (6.86 to 16.5), NNT 3; sedation or drowsiness 1.66 (1.46 to 1.89), NNT 5; euphoria 12.5 (3.00 to 52.1), NNT 7. Harmful side effects also occurred more often with cannabinoids: dizziness 2.97 (2.31 to 3.83), NNT 3; dysphoria or depression 8.06 (3.38 to 19.2), NNT 8; hallucinations 6.10 (2.41 to 15.4), NNT 17; paranoia 8.58 (6.38 to 11.5), NNT 20; and arterial hypotension 2.23 (1.75 to 2.83), NNT 7. Patients given cannabinoids were more likely to withdraw due to side effects 4.67 (3.07 to 7.09), NNT 11.

CONCLUSIONS

In selected patients, the cannabinoids tested in these trials may be useful as mood enhancing adjuvants for controlling chemotherapy related sickness. Potentially serious adverse effects, even when taken short term orally or intramuscularly, are likely to limit their widespread use.

Cannabinoids for control of chemotherapy induced nausea and vomiting: quantitative systematic review

OBJECTIVE

To quantify the antiemetic efficacy and adverse effects of cannabis used for sickness induced by chemotherapy.

DESIGN

Systematic review.

DATA SOURCES

Systematic search (Medline, Embase, Cochrane library, bibliographies), any language, to August 2000.

STUDIES

30 randomised comparisons of cannabis with placebo or antiemetics from which dichotomous data on efficacy and harm were available (1366 patients). Oral nabilone, oral dronabinol (tetrahydrocannabinol), and intramuscular levonantradol were tested. No cannabis was smoked. Follow up lasted 24 hours.

RESULTS

Cannabinoids were more effective antiemetics than prochlorperazine, metoclopramide, chlorpromazine, thiethylperazine, haloperidol, domperidone, or alizapride: relative risk 1.38 (95% confidence interval 1.18 to 1.62), number needed to treat 6 for complete control of nausea; 1.28 (1.08 to 1.51), NNT 8 for complete control of vomiting. Cannabinoids were not more effective in patients receiving very low or very high emetogenic chemotherapy. In crossover trials, patients preferred cannabinoids for future chemotherapy cycles: 2.39 (2.05 to 2.78), NNT 3. Some potentially beneficial side effects occurred more often with cannabinoids: "high" 10.6 (6.86 to 16.5), NNT 3; sedation or drowsiness 1.66 (1.46 to 1.89), NNT 5; euphoria 12.5 (3.00 to 52.1), NNT 7. Harmful side effects also occurred more often with cannabinoids: dizziness 2.97 (2.31 to 3.83), NNT 3; dysphoria or depression 8.06 (3.38 to 19.2), NNT 8; hallucinations 6.10 (2.41 to 15.4), NNT 17; paranoia 8.58 (6.38 to 11.5), NNT 20; and arterial hypotension 2.23 (1.75 to 2.83), NNT 7. Patients given cannabinoids were more likely to withdraw due to side effects 4.67 (3.07 to 7.09), NNT 11.

CONCLUSIONS

In selected patients, the cannabinoids tested in these trials may be useful as mood enhancing adjuvants for controlling chemotherapy related sickness. Potentially serious adverse effects, even when taken short term orally or intramuscularly, are likely to limit their widespread use.

Are cannabinoids an effective and safe treatment option in the management of pain? A qualitative systematic review

OBJECTIVE

To establish whether cannabis is an effective and safe treatment option in the management of pain.

DESIGN

Systematic review of randomised controlled trials.

DATA SOURCES

Electronic databases Medline, Embase, Oxford Pain Database, and Cochrane Library; references from identified papers; hand searches.

STUDY SELECTION

Trials of cannabis given by any route of administration (experimental intervention) with any analgesic or placebo (control intervention) in patients with acute, chronic non-malignant, or cancer pain. Outcomes examined were pain intensity scores, pain relief scores, and adverse effects. Validity of trials was assessed independently with the Oxford score.

DATA EXTRACTION

Independent data extraction; discrepancies resolved by consensus.

DATA SYNTHESIS

20 randomised controlled trials were identified, 11 of which were excluded. Of the 9 included trials (222 patients), 5 trials related to cancer pain, 2 to chronic non-malignant pain, and 2 to acute postoperative pain. No randomised controlled trials evaluated cannabis; all tested active substances were cannabinoids. Oral delta-9-tetrahydrocannabinol (THC) 5-20 mg, an oral synthetic nitrogen analogue of THC 1 mg, and intramuscular levonantradol 1.5-3 mg were about as effective as codeine 50-120 mg, and oral benzopyranoperidine 2-4 mg was less effective than codeine 60-120 mg and no better than placebo. Adverse effects, most often psychotropic, were common.

CONCLUSION

Cannabinoids are no more effective than codeine in controlling pain and have depressant effects on the central nervous system that limit their use. Their widespread introduction into clinical practice for pain management is therefore undesirable. In acute postoperative pain they should not be used. Before cannabinoids can be considered for treating spasticity and neuropathic pain, further valid randomised controlled studies are needed.

Nitric oxide synthase as a marker in colorectal carcinoma

Elevated inducible nitric oxide synthase (iNOS) activity has been found in 60 per cent of colon adenomas and 20 to 50 per cent of adenocarcinomas. We postulated that high levels of iNOS may increase the invasive and metastatic potential of colon carcinoma and could be indicative of survival potential. Data were reviewed for 52 patients with colorectal carcinoma diagnosed in 1991 and 1992. Specimens were stained for iNOS and catalogued as low-activity staining (LAS) or high-activity staining (HAS) on the basis of visual evaluation by three pathologists. Thirty patients were LAS and 22 HAS. Age, sex, preoperative carcinoembryonic antigen, tumor and nodal status, and American Joint Committee on Cancer staging were not different between groups. Forty-six per cent of the HAS group remained alive after 5 years versus 71 per cent in the LAS group. Survival was significantly lower and metastatic status significantly higher in the HAS group. Results indicated that iNOS activity may be a prognostic indicator of long-term survival potential after treatment for colon cancer. In addition results suggested that metastasis was greater in colon carcinoma specimens that maintain an activated iNOS and that these cells clinically react more aggressively. Conclusions are tempered by the fact that results were based on a limited sample size.

Cecal volvulus causing postoperative intestinal obstruction: report of a case

Cecal volvulus is a rare cause of intestinal obstruction after major abdominal surgery. A case of cecal volvulus occurring in the early postoperative period after left colon resection for malignancy is presented. Clinical evaluation and plain abdominal radiographs suggesting cecal volvulus prompted laparotomy and correction. Delay in diagnosis results in high mortality, and treatment depends largely on the viability of the involved intestine. This report describes the second case of cecal volvulus complicating a left colectomy. It was treated by detorsion and reperitonealization cecopexy.

Diffuse lamellar keratitis: isolation of endotoxin and demonstration of the inflammatory potential in a rabbit laser in situ keratomileusis model

PURPOSE

To systematically examine sources of endotoxin contamination in eye centers as a potential cause of diffuse lamellar keratitis (DLK) and to demonstrate the inflammatory potential of endotoxin in a rabbit model of laser in situ keratomileusis (LASIK) surgery.

SETTING

University of Calgary, Calgary, Alberta, Canada.

METHODS

In this prospective study, all water sources that routinely come in contact with LASIK instruments, including sterilizer reservoirs, eyedrops, microkeratome blades, and cleaning solutions, were examined for endotoxins at 5 eye centers. Bacterial cultures were performed on water samples from 5 sterilizer reservoirs. A LASIK flap was created in 8 rabbit eyes using an Automated Corneal Shaper microkeratome (Bausch & Lomb). The flaps were reflected, and a dose of endotoxin at various concentrations was placed on the interface. After 1 minute, the flap was irrigated and repositioned. The rabbit eyes were examined daily with a slitlamp biomicroscope for 3 days for the development of DLK, which was classified on a scale from grade 1 to 4 (mild to severe). The rabbits were killed at the conclusion of the study, and the interfaces were stained to rule out infectious etiologies.

RESULTS

Endotoxin was detected in significant concentrations in tap water, filtered and distilled water, instrument washbasins, and sterilizer reservoirs at all 5 centers. The cultures of the water samples taken from the sterilizer reservoirs ranged from no growth to the presence of >100 colony-forming units of Flavobacterium and Pseudomonas aeruginosa. Endotoxins caused DLK-like interface inflammation in all eyes tested. Examination of stained scrapings showed no microorganisms in the interface of the rabbit eyes.

CONCLUSION

Endotoxin contamination was detected in water sources that routinely come in contact with LASIK instruments. Endotoxins were capable of inducing interface inflammation in a rabbit model and may therefore be a significant factor in epidemic DLK.

Detection of Viral DNA and E4 Protein in Basal Keratinocytes of Experimental Canine Oral Papillomavirus Lesions

We studied experimental canine oral papillomavirus (COPV) infection by in situ hybridization and immunohistochemistry of weekly biopsies. After 4 weeks, viral DNA in rete ridges suggested a keratinocyte stem cell target. Abundant viral DNA was seen in E4-positive cells only. E4 was predominantly cytoplasmic but also nuclear, being concentrated in the nucleoli during wart formation. Infected cells spread laterally along the basal layer and into the parabasal layers, accompanied by E7 transcription and increased mitoses. Most of the lower epithelium was positive for viral DNA, but, in mature warts, higher levels of E4 expression and genome amplification occurred in only sporadic superficial cells. L1 expression was late and in only a subset of E4-positive cells. During regression, viral DNA was less abundant in deep epithelial layers, suggesting downregulation of replication prior to replacement of infected cells from beneath. Detection of viral DNA in post-regression tissue indicated latent infection.

Regression of canine oral papillomas is associated with infiltration of CD4+ and CD8+ lymphocytes

Canine oral papillomavirus (COPV) infection is used in vaccine development against mucosal papillomaviruses. The predictable, spontaneous regression of the papillomas makes this an attractive system for analysis of cellular immunity. Immunohistochemical analysis of the timing and phenotype of immune cell infiltration revealed a marked influx of leukocytes during wart regression, including abundant CD4+ and CD8+ cells, with CD4+ cells being most numerous. Comparison of these findings, and those of immunohistochemistry using TCRalphabeta-, TCRgammadelta-, CD1a-, CD1c-, CD11a-, CD11b-, CD11c-, CD18-, CD21-, and CD49d-specific monoclonal antibodies, with previously published work in the human, ox, and rabbit models revealed important differences between these systems. Unlike bovine papillomavirus lesions, those of COPV do not have a significant gamma/delta T-cell infiltrate. Furthermore, COPV lesions had numerous CD4+ cells, unlike cottontail rabbit papillomavirus lesions. The lymphocyte infiltrate in the dog resembled that in human papillomavirus lesions, indicating that COPV is an appropriate model for human papillomavirus immunity.

Intra-epithelial vaccination with COPV L1 DNA by particle-mediated DNA delivery protects against mucosal challenge with infectious COPV in beagle dogs

Protection against viral challenge with canine oral papillomavirus (COPV) was achieved by immunisation via particle-mediated DNA delivery (PMDD) of a plasmid encoding the COPV L1 gene to cutaneous and oral mucosal sites in beagle dogs. The initial dose of approximately 9 microg of DNA was followed by two booster doses at 6 week intervals. A similar approach was used to vaccinate a control group of animals with plasmid DNA encoding the Hepatitis B virus S gene. Following challenge at the oral mucosa with COPV all animals vaccinated with the COPV L1 gene were protected against disease. However five of six animals in the control group developed COPV induced papillomas at the oral mucosa. Both cell-mediated lymphoproliferative and humoral antibody responses to the DNA vaccine were observed. Our data indicate that PMDD of plasmid DNA can protect against mucosal challenge with papillomavirus.

Seeking a simple measure of analgesia for mega-trials: is a single global assessment good enough?

We sought to investigate the potential of using a simple global estimation ('How effective do you think the treatment was?') as a measure of efficacy by comparing it with at least 50%maxTOTPAR (at least 50% of the maximum possible pain relief) in acute pain studies. One hundred and fifty randomized, double-blind trials included in 11 systematic reviews of single dose, oral analgesics for postoperative pain were used as a source of data. The relationship between the proportion of patients reporting the top two or three values on a five-point global scale and the proportion with at least 50%maxTOTPAR was investigated. Twenty-six trials provided data on the proportion reporting the top two categories (very good or excellent) and 27 gave data on the top three categories (good, very good or excellent). The relationship between the percentage of patients recording the top two categories on a five-point global scale and the proportion with at least 50%maxTOTPAR was fair (r(2)=0.67). That for the top three categories was less good (r(2)=0.57). Similar numbers-needed-to-treat were calculated for aspirin 600/650 mg and ibuprofen 400 mg using at least 50%maxTOTPAR and the top two categories. No real difference was seen in the correlation for standard wording compared to non-standard wording. Individual patient data were also used from four randomized, placebo-controlled, double-blind trials in postoperative pain. The frequency distribution for %maxTOTPAR was plotted for patients reporting each of the five categories on the global scale. A global assessment provides similar measures of analgesic efficacy as TOTPAR derived from hourly measurements, but the effects of adverse effects have yet to be understood.

Colonoscopy in octogenarians and older patients

INTRODUCTION

Colonoscopy in the elderly has been considered by many to be risky because of mechanical bowel preparation and dehydration, electrolyte disturbances, conscious sedation, and hypoxic complications. We hypothesized that colonoscopy in octogenarians and older patients is a safe procedure.

MATERIALS AND METHODS

A retrospective review of 803 patients who underwent colonoscopy from January 1997 to October 1997 was performed. The patients were grouped by age: group A (17-49 years) had 166 patients (20%); group B (50-79 years) had 534 patients (67%); and group C (80 years and older) had 103 patients (13%). Results were considered significant at p value less than 0.05 unless otherwise noted.

RESULTS

Blood in the stool (84%) and history of colonic vascular disease (5.8%) were the most common indication in group C (84%). Colonoscopy was used in group A (18%) more often than in the other groups to rule out inflammatory bowel disease. History of colon polyps was a more common indication in group B (20%) than in the other groups. Group A had a significantly higher incidence of normal examinations (84%) and diagnosis of inflammatory bowel disease (14%). Group B had a higher incidence of polyps than the other groups. Group C had the highest incidence of vascular disease (15%). Diverticular disease and carcinoma were more common in groups B (37%) and C (52%). The amount of sedation in the groups did not significantly differ. Completion of the colonoscopy to the cecum or anastomotic sites did not differ among the groups (p > 0.05), nor did complication rates among groups (p > 0.05).

CONCLUSIONS

Colonoscopy is safe in octogenarians and older patients. Age does not, by itself, confer an increased risk to the procedure.

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.

REVIEWER'S CONCLUSIONS

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

Transcutaneous electrical nerve stimulation (TENS) for chronic pain

BACKGROUND

Transcutaneous electrical nerve stimulation (TENS) is used in a variety of different clinical settings to treat a range of different acute and chronic pain conditions and has become popular with both patients and health professionals.

OBJECTIVES

To evaluate the effectiveness of TENS in chronic pain.

SEARCH STRATEGY

The Cochrane Library, Embase, Medline, CINAHL and The Oxford Pain Database were searched. Reference lists from retrieved reports and reviews were examined. Date of the most recent search: March 1999.

SELECTION CRITERIA

RCTs were eligible if they included the following treatment comparisons: active TENS versus sham TENS controls active TENS versus no treatment controls active TENS versus active TENS controls (for instance High Frequency TENS vs Low Frequency TENS) Studies of patients suffering chronic pain for three months or more which included subjective outcome measures for pain intensity, or pain relief were eligible for evaluation in this review. No restrictions were made to language or sample size. Data from abstracts, letters, or unpublished studies, and studies of TENS in angina, headache and migraine, and dysmenorrhoea were not included.

DATA COLLECTION AND ANALYSIS

Data were extracted and summarised on the following items: patients and details of pain condition, study treatments, study duration, design, methods, subjective pain outcome measures, methodological quality, results for pain outcome measures and adverse effects, and the conclusions made by the authors of the original studies. Extracted data and methodological quality of each report was confirmed by at least three of the reviewers.

MAIN RESULTS

Of 107 reports identified from the searches, 88 were excluded as they did not fulfil the pre-defined entry criteria. Nineteen RCTs (from 18 reports) were evaluated. The included trials varied in terms of design, analgesic outcomes, chronic pain conditions, TENS treatments and overall methodological quality. Studies included single and multiple dose treatment comparisons of TENS. The studies were small. The reporting of the methods used and results for the analgesic outcomes were generally poor. TENS treatments and controls were often poorly defined. Few studies evaluated the long-term analgesic effectiveness of TENS and single dose evaluations of TENS are unhelpful in making clinical decisions of the long-term effectiveness of TENS in the management of chronic pain. Meta-analysis was not possible. Overall in 10 of 15 inactive control studies there was a positive analgesic outcome in favour of the active TENS treatments. For the multiple dose treatment comparison studies only three of seven were considered to be in favour of the active TENS treatments. For the active controlled studies, seven studies made direct comparisons between HFTENS and LFTENS. Five of seven studies could find no difference in terms of analgesic efficacy between HFTENS and LFTENS at any time point.

REVIEWER'S CONCLUSIONS

The results of this review are inconclusive; the published trials do not provide information on the stimulation parameters which are most likely to provide optimum pain relief, nor do they answer questions about long-term effectiveness. Large multi-centre randomised controlled trials of TENS in chronic pain are urgently needed.

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.

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), 4.5 (4.0 to 5.1) 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.

REVIEWER'S 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.

Single-dose dipyrone for acute postoperative pain

BACKGROUND

The use of dipyrone as an analgesic is controversial. It is used most commonly to treat postoperative pain, colic pain, cancer pain and migraine, and in many countries, eg, Russia, Spain, Brazil, and in many parts of South-America and Africa, it is the most popular non opioid first line analgesic. In others it has been banned (e.g. USA, UK) because of its association with potentially life-threatening blood dyscrasias such as agranulocytosis. Dipyrone is currently available in Austria, Belgium, France, Germany, Italy, The Netherlands, Spain, Switzerland, South Africa, Latin America, Russia, Israel and India.

OBJECTIVES

To assess quantitatively the analgesic efficacy and adverse effects of single-dose dipyrone in randomised trials in moderate to severe postoperative pain. To compare the relative efficacy of dipyrone with other drugs assessed in the same way.

SEARCH STRATEGY

Published reports were identified from Medline, Embase, the Cochrane Library (Issue 3 1999), LILACs and the Oxford Pain Relief Database. Additional studies were identified from bibliographies of retrieved reports. Date of the most recent search: December 1999.

SELECTION CRITERIA

The following inclusion criteria were used: full journal publication, clinical trial, random allocation of patients to treatment groups, double-blind design, adult patients, pain of moderate to severe intensity at the baseline assessment, postoperative administration of study drugs, treatment arms which included dipyrone and placebo or active control and oral, rectal, intramuscular or intravenous administration of study drugs.

DATA COLLECTION AND ANALYSIS

Summed pain intensity and pain relief data over 4-6 hours were extracted and converted into dichotomous information to yield the number of patients who obtained at least 50% pain relief. This was used to calculate the proportion of patients with, and number-needed-to-treat for, at least 50% pain relief over 4-6 hours. Single-dose adverse effect data were collected.

MAIN RESULTS

Fifteen studies were included; eight used placebo and seven used an active control (oral dexketoprofen 12.5 mg or 25 mg, oral ketorolac 10 mg, intramuscular pethidine 100 mg or ketorolac 30 mg, intravenous tramadol 100 mg or rectal suprofen 300 mg). In five trials (288 patients) the mean response rate (proportion of patients with at least 50% pain relief) for single dose oral dipyrone 500 mg was 73% (range 54% to 87%) and with placebo it was 32% (19% to 41%) in moderate to severe postoperative pain over 4-6 hours. In two studies (113 patients) the response rate with oral dipyrone 1 g was 69% (61% and 77%) and with placebo it was 20% (11% and 25%). In one study (70 patients) the response rate with intramuscular dipyrone 2 g was 74% and with placebo it was 46%. No analyses could be conducted for adverse effects. The response rates in the active controlled trials were similar to those reported in the placebo controlled trials.

REVIEWER'S CONCLUSIONS

Single-dose dipyrone appears to be of similar efficacy to ibuprofen 400 mg and other analgesics frequently used in the treatment of moderate to severe postoperative pain. The commonest adverse effects were somnolence, gastric discomfort and nausea.

Antidepressants and anticonvulsants for diabetic neuropathy and postherpetic neuralgia: a quantitative systematic review

To determine the relative efficacy and adverse effects of antidepressants and anticonvulsants in the treatment of diabetic neuroapathy and postherpetic neuralgia, published reports were identified from a variety of electronic databases, including Medline, EMBASE, the Cochrane Library and the Oxford Pain Relief Database, and from two previously published reviews. Additional studies were identified from the reference lists of retrieved reports. The relative benefit (RB) and number-needed-to-treat (NNT) for one patient to achieve at least 50 % pain relief was calculated from available dichotomous data, as was the relative risk (RR) and number-needed-to-harm (NH) for minor adverse effects and drug related study withdrawal. In diabetic neuropathy, 16 reports compared antidepressants with placebo (491 patient episodes) and three compared anticonvulsants with placebo (321). The NNT for at least 50 % pain relief with antidepressants was 3.4 (95 % confidence interval 2.6-4. 7) and with anticonvulsants 2. 7 (2. 2-3. 8). In postherpetic neuralgia, three reports compared antidepressants with placebo (145 patient episodes) and one compared anticonvulsants with placebo (225), giving an NNT with antidepressants of 2.1 (1. 7-3) and with anticonvulsants 3.2 (2.4-5). There was little difference in the incidence of minor adverse effects with either antidepressants or anticonvulsants compared with placebo, with 1VH (minor) values of about 3. For drug-related study withdrawal, antidepressants had an NNH (major) of 17 (11-43) compared with placebo, whereas with anticonvulsants there was no significant difference from placebo. Antidepressants and anticonvulsants had the same efficacy and incidence of minor adverse effects in these tzoo neuropathic pain conditions. There was no evidence that selective serotonin reuptake inhibitors (SSRIs) were better than older antidepressants, and no evidence that gabapentin was better than older anticonvulsants. In these trials patients were more likely to stop taking antidepressants than anticonvulsants because of adverse effects.

Divergent functional properties of ryanodine receptor types 1 and 3 expressed in a myogenic cell line

Of the three known ryanodine receptor (RyR) isoforms expressed in muscle, RyR1 and RyR2 have well-defined roles in contraction. However, studies on mammalian RyR3 have been difficult because of low expression levels relative to RyR1 or RyR2. Using the herpes simplex virus 1 (HSV-1) helper-free amplicon system, we expressed either RyR1 or RyR3 in 1B5 RyR-deficient myotubes. Western blot analysis revealed that RyR1- or RyR3-transduced cells expressed the appropriate RyR isoform of the correct molecular mass. Although RyR1 channels exhibited the expected unitary conductance for Cs(+) in bilayer lipid membranes, 74 of 88 RyR3 channels exhibited pronounced subconductance behavior. Western blot analysis with an FKBP12/12.6-selective antibody reveals that differences in gating behavior exhibited by RyR1 and RyR3 may be, in part, the result of lower affinity of RyR3 for FKBP12. In calcium imaging studies, RyR1 restored skeletal-type excitation-contraction coupling, whereas RyR3 did not. Although RyR3-expressing myotubes were more sensitive to caffeine than those expressing RyR1, they were much less sensitive to 4-chloro-m-cresol (CMC). In RyR1-expressing cells, regenerative calcium oscillations were observed in response to caffeine and CMC but were never seen in RyR3-expressing 1B5 cells. In [(3)H]ryanodine binding studies, only RyR1 exhibited sensitivity to CMC, but both RyR isoforms responded to caffeine. These functional differences between RyR1 and RyR3 expressed in a mammalian muscle context may reflect differences in association with accessory proteins, especially FKBP12, as well as structural differences in modulator binding sites.

Postoperative analgesia and vomiting, with special reference to day-case surgery: a systematic review

BACKGROUND

Day-case surgery is of great value to patients and the health service. It enables many more patients to be treated properly, and faster than before. Newer, less invasive, operative techniques will allow many more procedures to be carried out. There are many elements to successful day-case surgery. Two key components are the effectiveness of the control of pain after the operation, and the effectiveness of measures to minimise postoperative nausea and vomiting.

OBJECTIVES

To enable those caring for patients undergoing day-case surgery to make the best choices for their patients and the health service, this review sought the highest quality evidence on: (1) the effectiveness of the control of pain after an operation; (2) the effectiveness of measures to minimise postoperative nausea and vomiting.

METHODS

Full details of the search strategy are presented in the report. RESULTS - ANALGESIA: The systematic reviews of the literature explored whether different interventions work and, if they do work, how well they work. A number of conclusions can be drawn. RESULTS-ANALGESIA, INEFFECTIVE INTERVENTIONS: There is good evidence that some interventions are ineffective. They include: (1) transcutaneous electrical nerve stimulation in acute postoperative pain; (2) the use of local injections of opioids at sites other than the knee joint; (3) the use of dihydrocodeine, 30 mg, in acute postoperative pain (it is no better than placebo). RESULTS-ANALGESIA, INTERVENTIONS OF DOUBTFUL VALUE: Some interventions may be effective but the size of the effect or the complication of undertaking them confers no measurable benefit over conventional methods. Such interventions include: (1) injecting morphine into the knee joint after surgery: there is a small analgesic benefit which may last for up to 24 hours but there is no clear evidence that the size of the benefit is of any clinical value; (2) manoeuvres to try and anticipate pain by using pre-emptive analgesia; these are no more effective than standard methods; (3) administering non-steroidal anti-inflammatory drugs (NSAIDs) by injection or per rectum in patients who can swallow; this appears to be no more effective than giving NSAIDs by mouth and, indeed, may do more harm than good; (4) administering codeine in single doses; this has poor analgesic efficacy. RESULTS-ANALGESIA, INTERVENTIONS OF PROVEN VALUE: These include a number of oral analgesics including (at standard doses): (1) dextropropoxyphene; (2) tramadol; (3) paracetamol; (4) ibuprofen; (5) diclofenac. Diclofenac and ibuprofen at standard doses give analgesia equivalent to that obtained with 10 mg of intramuscular morphine. Each will provide at least 50% pain relief from a single oral dose in patients with moderate or severe postoperative pain. Paracetamol and codeine combinations also appear to be highly effective, although there is little information on the standard doses used in the UK. The relative effectiveness of these analgesics is compared in an effectiveness 'ladder' which can inform prescribers making choices for individual patients, or planning day-case surgery. Dose-response relationships show that higher doses of ibuprofen may be particularly effective. Topical NSAIDs (applied to the skin) are effective in minor injuries and chronic pain but there is no obvious role for them in day-case surgery. RESULTS-POSTOPERATIVE NAUSEA AND VOMITING: The proportion of patients who may feel nauseated or vomit after surgery is very variable, despite similar operations and anaesthetic techniques. Systematic review can still lead to clear estimations of effectiveness of interventions. Whichever anti-emetic is used, the choice is often between prophylactic use (trying to prevent anyone vomiting) and treating those people who do feel nauseated or who may vomit. Systematic reviews of a number of different anti-emetics show clearly that none of the anti-emetics is sufficiently effective to be used for prophylaxis. (ABSTRACT TRUNCATE

The role of Mucodyne in reducing the need for surgery in patients with persistent otitis media with effusion

A recent meta-analysis suggested a possible beneficial effect of carboxymethylcysteine (Mucodyne) in resolving otitis media with effusion (OME), but the methodology in several of the included trials was flawed. A double-blind randomised controlled trial (RCT) involving 163 patients (78 randomised to Mucodyne and 85 to placebo) was therefore performed.

MAIN OUTCOME MEASURE

operative intervention or not. Of the 28 patients with resolved OME, 17 were in the Mucodyne group and 11 in the placebo group. Although it appeared that patients treated with Mucodyne were 1.68 times more likely to undergo resolution of OME than patients receiving placebo, this did not reach statistical significance. [Risk ratio of 1.68 (95% C.I., 0.74-3.37)]. chi2 test (df = 162) = 2.24 (P = 0.134). The absolute risk difference in the study was 8.5% (95% C.I., -3-20). We cannot exclude the possibility that Mucodyne is as beneficial as a 20% additional resolution of OME, or as harmful as a 3% decrease in the resolution of OME.

Current perspectives in evidence-based laboratory medicine

This review examines some of the current perspectives in evidence-based laboratory medicine. From evidence-based medicine, which has concentrated mainly on treatments, we have learned that systematic reviews of the literature are the major way of producing high-quality evidence. This is because systematic reviews search all the literature, apply quality standards to ensure that only the best evidence is available, and aggregate a sufficient weight of information to inform on both the direction of a result (that a treatment works) and the magnitude of the result (how good the treatment is). In laboratory medicine, we have few systematic reviews. Even those we do have give little insight into features of studies which provide the closest view of the 'truth'. It may well be that current studies of laboratory tests are just not good enough. Often, they are too limited in scope, too small, and choose inappropriate patient populations. In the future, comprehensive, prospective and large studies should examine patient demographics and clinical history, as well as laboratory findings. This will better predict those features that are most closely associated with the correct diagnosis in a particular clinical situation. Clinical decision rules combining all available data will be the best way forward.

Teasing apart quality and validity in systematic reviews: an example from acupuncture trials in chronic neck and back pain

The objectives of the study were (1) to carry out a systematic review to assess the analgesic efficacy and the adverse effects of acupuncture compared with placebo for back and neck pain and (2) to develop a new tool, the Oxford Pain Validity Scale (OPVS), to measure validity of findings from randomized controlled trials (RCTs), and to enable ranking of trial findings according to validity within qualitative reviews. Published RCTs (of acupuncture at both traditional and non-traditional points) were identified from systematic searching of bibliographic databases (e.g. MEDLINE) and reference lists of retrieved reports. Pain outcome data were extracted with preference given to standardized outcomes such as pain intensity. Information on adverse effects was also extracted. All included trials were scored using a five-item 0-16 point validity scale (OPVS). The individual RCTs were ranked according to their OPVS score to enable more weight to be placed on the trials of greater validity when drawing an overall conclusion about the efficacy of acupuncture for relieving neck and back pain. Statistical analyses were carried out on the OPVS scores to assess the relationship between trial finding (positive or negative) and validity. Thirteen RCTs met the inclusion criteria. Five trials concluded that acupuncture was effective, and eight concluded that it was not effective for relieving back or neck pain. There was no obvious difference between the findings of trials using traditional and non-traditional points. Using the new OPVS scale, the validity scores of the included trials ranged from 4 to 14. There was no significant relationship between OPVS score and trial finding (positive versus negative). Authors' conclusions did not always agree with their data. We drew our own conclusions (positive/negative) based on the data presented in the reports. Re-analysis using our conclusions showed a significant relationship between OPVS score and trial finding, with higher validity scores associated with negative findings. OPVS is a useful tool for assessing the validity of trials in qualitative reviews. With acupuncture for chronic back and neck pain, we found that the most valid trials tended to be negative. There is no convincing evidence for the analgesic efficacy of acupuncture for back or neck pain.

Women's knowledge of, and attitudes to, contraceptive effectiveness and adverse health effects

Our objectives were to determine women's knowledge of the effectiveness of different contraceptive methods and the risks of thrombosis with use of hormonal contraceptives, and their attitudes regarding the acceptability of bleeding irregularities and weight change. An additional aim was to determine what information women want to be given about contraceptives. In order to satisfy the study objectives, a series of semi-structured focus groups was conducted with women of differing life-stage and background from Oxford. Quantitative data were collected using a structured questionnaire. Qualitative data were collected through discussion with group members. Forty-five women attended four focus groups. Women were segregated into the following groups: professional working mothers; non-professional mothers; young, unmarried professional women; and undergraduate students. Women tended to overestimate the risks and underestimate the effectiveness of hormonal contraceptives. They were resistant to interference with their bleeding patterns and weight.

Quantitative estimation of rare adverse events which follow a biological progression: a new model applied to chronic NSAID use

Randomised controlled trials (RCTs) alone are unlikely to provide reliable estimates of the incidence of rare events because of their limited size. Cohort, case control, and other observational studies have large numbers but are vulnerable to various kinds of bias. Wanting to estimate the risk of death from bleeding or perforated gastroduodenal ulcers with chronic usage of non-steroidal anti-inflammatory drugs (NSAIDs) with greater precision, we developed a model to quantify the frequency of rare adverse events which follow a biological progression. The model combined data from both RCTs and observational studies. We searched systematically for any report of chronic (>/=2 months) use of NSAIDs which gave information on gastroduodenal ulcer, bleed or perforation, death due to these complications, or progression from one level of harm to the next. Fifteen RCTs (19364 patients exposed to NSAIDs for 2-60 months), three cohort studies (215076 patients redeeming a NSAID prescription over a 3-12 month period), six case-control studies (2957 cases) and 20 case series (7406), and case reports (4447) were analysed. In RCTs the incidence of bleeding or perforation in 6822 patients exposed to NSAIDs was 0.69%; two deaths occurred. Of 11040 patients with bleeding or perforation with or without NSAID exposure across all reports, 6-16% (average 12%) died; the risk was lowest in RCTs and highest in case reports. Death from bleeding or perforation in all controls not exposed to NSAIDs occurred in 18 out of 849489 (0.002%). From these numbers we calculated the number-needed-to-treat for one patient to die due to gastroduodenal complications with chronic (>/=2 months) NSAIDs as 1/((0.69x¿6-16%, average 12%¿)-0.002%))=909-2500 (average 1220). On average 1 in 1200 patients taking NSAIDs for at least 2 months will die from gastroduodenal complications who would not have died had they not taken NSAIDs. This extrapolates to about 2000 deaths each year in the UK.

HSV-1 amplicon vectors are a highly efficient gene delivery system for skeletal muscle myoblasts and myotubes

Analysis of RyR1 structure function in muscle cells is made difficult by the low (<5%) transfection efficiencies of myoblasts or myotubes using calcium phosphate or cationic lipid techniques. We inserted the full-length 15.3-kb RyR1 cDNA into a herpes simplex virus type 1 (HSV-1) amplicon vector, pHSVPrPUC between the ori/IE 4/5 promoter sequence and the HSV-1 DNA cleavage/packaging signal (pac). pHSVGN and pHSVGRyR1, two amplicons that expressed green fluorescent protein, were used for fluorescence-activated cell sorter analysis of transduction efficiency. All amplicons were packaged into HSV-1 virus particles using a helper virus-free packaging system and yielded 10(6) transducing vector units/ml. HSVRyR1, HSVGRyR1, and HSVGN virions efficiently transduced mouse myoblasts and myotubes, expressing the desired product in 70-90% of the cells at multiplicity of infection 5. The transduced cells appeared healthy and RyR1 produced by this method was targeted properly and restored skeletal excitation-contraction coupling in dyspedic myotubes. The myotubes produced sufficient protein to allow single-channel analyses from as few as 10 100-mm dishes. In most cases this method could preclude the need for permanent transfectants for the study of RyR1 structure function.

Importance of radiation therapy for breast cancer patients treated with high-dose chemotherapy and stem cell transplant

PURPOSE

To determine local-regional failure rates in breast cancer patients treated with surgery and high-dose chemotherapy with stem cell transplant and to relate local-regional failure to the use and timing of radiation treatment.

METHODS AND MATERIALS

We retrospectively reviewed the records of 165 breast cancer patients treated on institutional protocols with surgery and high-dose chemotherapy with stem cell transplant. All patients had either Stage III disease, 10 or more positive axillary lymph nodes, or 4 or more positive axillary lymph nodes following neoadjuvant chemotherapy. Twelve patients had inflammatory breast cancer. Thirteen patients treated with breast preservation and 5 patients who died from toxicity within 30 days of transplant were excluded from the analyses of local-regional recurrences. In the remaining 147 patients, 108 were treated with adjuvant radiation and 39 were not. The disease stage distribution for these two groups was comparable. The median follow-up for surviving patients was 35 months.

RESULTS

The 3- and 5-year actuarial disease-free survival (DFS) for the entire group was 60% and 51%, respectively. The 5-year rates of freedom from isolated local-regional recurrence were 95% in the patients treated with adjuvant radiation and 86% in the patients who did not receive radiation (p = 0.014, log rank comparison). The 5-year rates of any local-regional recurrence as a first event (isolated recurrences plus those with simultaneous local-regional and distant recurrences) were 92% versus 82%, respectively for patients whose treatment did and did not include radiation (p = 0.038). We could not demonstrate a correlation of the timing of radiation with the risk of local-regional recurrence.

CONCLUSIONS

These data indicate that high-dose chemotherapy does not negate the importance of radiation in optimizing local-regional control in patients with high-risk breast cancer. Given the results of recent randomized trials studying postmastectomy radiation, which show that improving local-regional control improves overall survival (OS), we believe that all breast cancer patients with high-risk primary breast cancer who are treated with high-dose chemotherapy with stem cell transplant should receive radiation as a component of their treatment.

Single dose oral ibuprofen and diclofenac for postoperative pain

BACKGROUND

Ibuprofen and diclofenac are two widely used non-steroidal anti-inflammatory (NSAID) analgesics. It is therefore important to know which drug should be recommended for postoperative pain relief. This review seeks to compare the relative efficacy of the two drugs, and also considers the issues of safety and cost.

OBJECTIVES

To assess the analgesic efficacy of ibuprofen and diclofenac in single oral doses for moderate to severe postoperative pain.

SEARCH STRATEGY

Randomised trials were identified by searching Medline (1966 to December 1996), Embase (1980 to January 1997), the Cochrane Library (Issue 3 1996), Biological Abstracts (January 1985 to December 1996) and the Oxford Pain Relief Database (1950 to 1994). Date of the most recent searches: July 1998.

SELECTION CRITERIA

The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared either ibuprofen or diclofenac with placebo.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent reviewers, and trials were quality scored. Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Thirty-four trials compared ibuprofen and placebo (3,591 patients), six compared diclofenac with placebo (840 patients) and there were two direct comparisons of diclofenac 50 mg and ibuprofen 400 mg (130 patients). In postoperative pain the NNTs for ibuprofen 200 mg were 3.3 (95% confidence interval 2.8 to 4.0) compared with placebo, for ibuprofen 400 mg 2.7 (2.5 to 3.0), for ibuprofen 600 mg 2.4 (1.9 to 3.3), for diclofenac 50 mg 2.3 (2.0 to 2.7) and for diclofenac 100 mg 1.8 (1.5 to 2.1). Direct comparisons of diclofenac 50 mg with ibuprofen 400 mg showed no significant difference between the two.

REVIEWER'S CONCLUSIONS

Both drugs work well. Choosing between them is an issue of dose, safety and cost.

Single dose oxycodone and oxycodone plus paracetamol (acetominophen) for acute postoperative pain

BACKGROUND

Oxycodone is a strong opioid agonist which is useful for the management of severe pain. It is becoming increasingly important to assess the relative efficacy and harm caused by different treatments. This can be determined when an analgesic is compared with control under similar clinical circumstances.

OBJECTIVES

To quantitatively assess the analgesic efficacy and adverse effects of single-dose oxycodone and oxycodone plus paracetamol in randomised trials in acute postoperative pain.

SEARCH STRATEGY

Published reports were identified from Medline, Biological Abstracts, Embase, the Cochrane Library and the Oxford Pain Relief Database. Additional studies were identified from the reference lists of retrieved reports.

SELECTION CRITERIA

The inclusion criteria were: full journal publication, clinical trial, random allocation of adult patients to treatment groups, double blind design, moderate to severe baseline pain, postoperative administration of study drugs, treatment arms which included oxycodone or oxycodone plus paracetamol and placebo (or active control for which comparable efficacy data exist), and oral, intramuscular or intravenous administration of study drugs.

DATA COLLECTION AND ANALYSIS

Summed pain intensity and pain relief data over 4-6 hours were extracted and converted into dichotomous information yielding the number of patients obtaining at least 50% pain relief. Estimates of relative benefit and number-needed-to-treat were calculated. Single-dose adverse effect data were collected.

MAIN RESULTS

Seventy-seven reports were identified. Seven reports met the inclusion criteria; all assessed oral oxycodone. For efficacy, a significant benefit of active drug over placebo was shown for all doses of oxycodone and oxycodone plus paracetamol, except oxycodone 5 mg. For adverse effects, the number of patients reporting adverse effects was extracted for each dose of active drug versus placebo. When these data were pooled for the individual doses significantly more adverse effects with active drug than with placebo were shown for all doses, except oxycodone 5 mg and its combination with paracetamol 325 mg. This was also shown for drowsiness/somnolence. Significantly more nausea, vomiting and dizziness/lightheadedness were reported with oxycodone 10 mg plus paracetamol (650 mg and 1000 mg) than with placebo.

REVIEWER'S CONCLUSIONS

Single-dose oral oxycodone, with or without paracetamol, appears to be of comparable efficacy to intramuscular morphine and non-steroidal anti-inflammatory drugs. Central nervous system adverse effects were common.

Single dose dihydrocodeine for acute postoperative pain

BACKGROUND

Dihydrocodeine is a synthetic opioid analgesic developed in the early 1900s. Its structure and pharmacokinetics are similar to that of codeine and it is used for the treatment of postoperative pain or as an antitussive. It is becoming increasingly important to assess the relative efficacy and harm caused by different treatments. Relative efficacy can be determined when an analgesic is compared with control under similar clinical circumstances.

OBJECTIVES

To quantitatively assess the analgesic efficacy and adverse effects of single-dose dihydrocodeine compared with placebo in randomised trials in moderate to severe postoperative pain.

SEARCH STRATEGY

Published reports were identified from a variety of electronic databases including Medline, Biological Abstracts, Embase, the Cochrane Library and the Oxford Pain Relief Database. Additional studies were identified from the reference lists of retrieved reports.

SELECTION CRITERIA

The following inclusion criteria were used: full journal publication, clinical trial, random allocation of patients to treatment groups, double blind design, adult patients, pain of moderate to severe intensity at baseline, postoperative administration of study drugs, treatment arms which included dihydrocodeine and placebo and either oral or injected (intramuscular or intravenous) administration of study drugs.

DATA COLLECTION AND ANALYSIS

Data collection and analysis: Summed pain intensity and pain relief data over 4-6 hours were extracted and converted into dichotomous information to yield the number of patients obtaining at least 50% pain relief. This was used to calculate relative benefit and number-needed-to-treat for one patient to obtain at least 50% pain relief. Single-dose adverse effect data were collected and used to calculate relative risk and number-needed-to-harm.

MAIN RESULTS

Fifty-two reports were identified as possible randomised trials which assessed dihydrocodeine in postoperative pain. Four reports met the inclusion criteria; all assessed oral dihydrocodeine. Three reports (194 patients) compared dihydrocodeine with placebo and one (120 patients) compared dihydrocodeine (30 mg or 60 mg) with ibuprofen 400 mg. For a single dose of dihydrocodeine 30 mg in moderate to severe postoperative pain the NNT for at least 50% pain relief was 8.1 (95% confidence interval 4.1 to 540) when compared with placebo over a period of 4-6 hours. Pooled data showed significantly more patients to have reported adverse effects with dihydrocodeine 30 mg than with placebo. When compared to ibuprofen 400 mg both dihydrocodeine 30 mg and 60 mg were significantly inferior.

REVIEWER'S CONCLUSIONS

A single 30 mg dose of dihydrocodeine is not sufficient to provide adequate pain relief in postoperative pain. Statistical superiority of ibuprofen 400 mg over dihydrocodeine (30 mg or 60 mg) was shown.

Radiotherapy for the palliation of painful bone metastases

BACKGROUND

Radiotherapy is used commonly to provide pain relief for painful bone metastases, and there is a perception that of the three-quarters of patients who achieve pain relief, half of these stay free from pain. However, the precise contribution from radiotherapy may be unclear because of difficulties in assessing the numbers of people achieving relief, the extent of relief and its duration, and the influence of other contemporaneous interventions, such as analgesics.

OBJECTIVES

To assess pain relief from: 1. localised bone metastases achieved by radiotherapy, comparing the efficacy of different fractionation schedules 2. more generalised metastatic disease achieved by radiotherapy or radioisotopes.

SEARCH STRATEGY

Studies were identified by searching Medline (1966 to August 1998), Embase (1980 to 1998), the Cochrane Library (1998 Issue 3) and the Oxford Pain Relief Database (1950 to 1994).

SELECTION CRITERIA

The inclusion criteria used were: full journal publication, patients with pain due to bone metastases, and random allocation to a radiotherapeutic intervention (either external irradiation or administration of radioisotopes).

DATA COLLECTION AND ANALYSIS

The number of patients achieving complete pain relief and at least 50% at one month were compared with an assumed natural history of 1 in 100 patients achieving pain relief without treatment to obtain the number-needed-to-treat (NNT). Summed pain relief or pain intensity difference over four to six hours was extracted, converted into dichotomous information yielding the number of patients with at least 50% pain relief, and used to calculate the relative benefit and the NNT for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Twenty trials reported on 43 different radiotherapy fractionation schedules and eight studies of radioisotopes. Radiotherapy produced complete pain relief at one month in 395/1580 (25%) patients, and at least 50% relief in 788/1933 (41%) patients at some time during the trials. There were no differences in the proportions of patients achieving these outcomes between single or multiple fraction schedules. The number-needed-to-treat (NNT) to achieve complete relief at one month (compared with an assumed natural history of 1 in 100 patients whose pain resolved without treatment) was 4.2 (95% CI 3.7-4.7). No pooled estimates of speed of onset of relief, or of its duration, could be obtained. In the largest trial (759 patients) 52% of those who had complete relief had achieved it within four weeks, and the median duration of complete relief was 12 weeks. For more generalised disease, radioisotopes produced similar analgesic results to external irradiation. Adverse effect reporting was poor. There were no obvious differences between the various fractionation schedules in the incidence of nausea and vomiting, diarrhoea or pathological fractures.

REVIEWER'S CONCLUSIONS

Radiotherapy is clearly effective at reducing pain from painful bone metastases. There was no evidence of any difference in efficacy between different fractionation schedules, nor indeed of a dose-response with total dose of radiation. For treatment of generalised bone pain both hemibody irradiation and radioisotopes can reduce the number of painful new sites.

Single-dose ketorolac and pethidine in acute postoperative pain: systematic review with meta-analysis

For a systematic review of postoperative analgesic efficacy and adverse effects of single doses, injected or oral, of pethidine and ketorolac compared with placebo, we sought published randomized studies in moderate to severe postoperative pain. Information on summed pain intensity or pain relief outcomes over 4-6 h was extracted and converted to dichotomous information to produce the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. Minor and major adverse effect data were extracted and summarized. For pethidine 100 mg i.m., eight randomized, controlled studies met the inclusion criteria, with 203 patients given pethidine and 161 placebo. The NNT to produce at least 50% pain relief was 2.9 (95% confidence interval 2.3-3.9). At this dose, pethidine produced significantly more drowsiness and dizziness than placebo, with numbers-needed-to-harm (NNH) of 2.9 (2.2-4.4) and 7.2 (4.8-14), respectively. For ketorolac, 14 reports met the inclusion criteria (six i.m. and eight oral). Most i.m. information (176 patients) was available for the 30 mg dose, which had an NNT of 3.4 (2.5-4.9). Most oral information was available for the 10 mg dose, which had an NNT of 2.6 (2.3-3.1). Oral ketorolac 10 mg was consistently at least as effective as ketorolac 30 mg i.m. Only with oral ketorolac 10 mg were there significantly more adverse effects than with placebo, with an NNH for any adverse effect of 7.3 (4.7-17).

Single dose piroxicam for acute postoperative pain

BACKGROUND

Piroxicam is a non-steroidal anti-inflammatory drug (NSAID) with analgesic properties, and is used mainly for treating rheumatic disorders. Some drugs have been directly compared against each other within a trial setting to determine their relative efficacies, whereas other have not. It is possible, however, to compare analgesics indirectly by examining the effectiveness of each drug against placebo when used in similar clinical situations.

OBJECTIVES

To determine the analgesic efficacy and adverse effects of single-dose piroxicam compared with placebo in moderate to severe postoperative pain. To compare the effects of piroxicam with other analgesics.

SEARCH STRATEGY

Published reports were identified from systematic searching of Medline, Biological Abstracts, Embase, The Cochrane Library and the Oxford Pain Relief Database. Additional studies were identified from the reference lists of retrieved reports.

SELECTION CRITERIA

The following inclusion criteria were used: full journal publication, randomised placebo controlled trial, double-blind design, adult patients, postoperative pain of moderate to severe intensity at the baseline assessment, postoperative administration of oral or intramuscular piroxicam.

DATA COLLECTION AND ANALYSIS

Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients obtaining at least 50% pain relief. This was used to calculate estimates of relative benefit and number-needed-to-treat for one patient to obtain at least 50% pain relief. Information was collected on adverse effects and estimates of relative risk and number-needed-to-harm were calculated.

MAIN RESULTS

Three trials (141 patients) compared oral piroxicam 20 mg with placebo and one (15 patients) compared oral piroxicam 40 mg with placebo. For single doses of piroxicam 20 mg and 40 mg the respective numbers-needed-to-treat for at least 50% pain relief were 2.7 (2.1 to 3.8) [95% confidence interval] and 1.9 (1.2 to 4.3) [95% confidence interval] compared with placebo over 4-6 hours in moderate to severe postoperative pain. The reported incidence of adverse effects was no higher with piroxicam (20 mg or 40 mg) than with placebo.

REVIEWER'S CONCLUSIONS

Piroxicam appears to be of similar efficacy to other non-steroidal anti-inflammatory drugs (NSAIDs) and intramuscular morphine 10 mg when used as a single oral dose in the treatment of moderate to severe postoperative pain.

Single dose oral aspirin for acute pain

BACKGROUND

Aspirin has been known to be an effective analgesic for many years and is commonly used throughout the world for many different pain conditions. It is important for both prescribers and patients to have the best possible information about the efficacy and safety of analgesics, and this need is reflected in patient surveys which show that postoperative pain is often poorly managed. We also need to benchmark relative efficacy and safety of current analgesics so that we can compare them with new analgesics.

OBJECTIVES

To quantitatively assess the analgesic efficacy and adverse effects of a single-dose of aspirin in acute pain of moderate to severe intensity.

SEARCH STRATEGY

Randomised trials were identified by searching Medline (1966 to March 1998), Embase (1980 to January 1998), the Cochrane Library (Issue 1,1998) and the Oxford Pain Relief Database (1950 to 1994).

SELECTION CRITERIA

The inclusion criteria used were: full journal publication, postoperative pain or a mixture of postoperative and acute trauma pain, oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared aspirin with placebo.

DATA COLLECTION AND ANALYSIS

Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief.

MAIN RESULTS

Seventy-two randomised single-dose trials met our inclusion criteria, with 3253 patients given aspirin, and 3297 placebo. Significant benefit of aspirin over placebo was shown for aspirin 600/650 mg, 1000 mg and 1200 mg, NNTs for at least 50% pain relief of 4.4 (4.0 to 4.9), 4.0 (3.2 to 5.4) and 2.4 (1.9 to 3.2) respectively. Single-dose aspirin 600/650 mg produced significantly more drowsiness and gastric irritation than placebo, with a number-needed-to-harm (NNH) of 28 (19 to 52) and 38 (22 to 174) respectively. Type of pain model, pain measurement, sample size, quality of study design, and study duration had no significant impact on the results.

REVIEWER'S CONCLUSIONS

Aspirin is an effective analgesic for acute pain of moderate to severe intensity with a clear dose-response. Drowsiness and gastric irritation were seen as significant adverse effects even though the studies were single-dose. The pain relief achieved with aspirin was very similar milligram for milligram to that seen with paracetamol.

Naturally occurring, nonregressing canine oral papillomavirus infection: host immunity, virus characterization, and experimental infection

Papillomaviruses occasionally cause severe, nonregressing or recurrent infections in their human and animal hosts. The mechanisms underlying these atypical infections are not known. Canine oral papillomavirus (COPV) typically regresses spontaneously and is an important model of mucosal human papillomavirus infections. A severe, naturally occurring, nonregressing COPV infection provided an opportunity to investigate some aspects of viral pathogenicity and host immunity. In this case, the papillomas proved refractory to surgical and medical treatments, including autogenous vaccination and vaccination with capsid (L1) virus-like particles. High levels of induced anti-L1 antibodies appeared to have no effect on the infection. The papillomas spread to oesophageal mucosa, perioral haired skin, and remote cutaneous sites. Isolation of COPV from the animal and sequencing of several regions of the viral genome showed no differences to the COPV prototype. Experimental infection of beagle dogs with this viral isolate resulted in the uncomplicated development and regression of oral warts within the usual period, indicating that the virus was not an unusual pathogenic variant. These findings support the hypothesis that the recurrent lesions seen in some human papillomavirus infections, such as recurrent laryngeal papillomatosis, are associated with specific defects in host immunity rather than variations in viral pathogenicity.

Reporting of adverse effects in clinical trials should be improved: lessons from acute postoperative pain

We assessed the quality of assessment and reporting of adverse effects in randomized, double-blind clinical trials of single-dose acetaminophen or ibuprofen compared with placebo in moderate to severe postoperative pain. Reports were identified by systematic searching of a number of bibliographic databases (e.g., MEDLINE). Information on adverse effect assessment, severity and reporting, patient withdrawals, and anesthetic used was extracted. Compliance with former guidelines for adverse effect reporting was noted. Fifty-two studies were included; two made no mention of adverse effects. No method of assessment was given in 19 studies. Twenty trials failed to report the type of anesthetic used, eight made no mention of patient withdrawals, and nine did not state the severity of reported adverse effects. Only two studies described the method of assessment of adverse effect severity. When all adverse effect data were pooled, significantly more adverse effects were reported with active treatment than with placebo. For individual adverse effects, there was no difference between active (acetaminophen 1000 mg or ibuprofen 400 mg) and placebo; the exception was significantly more somnolence/drowsiness with ibuprofen 400 mg. Ninety percent of trials reporting somnolence/drowsiness with ibuprofen 400 mg were in dental pain. All studies published after 1994 complied with former guidelines for adverse effect reporting. Different methods of assessing adverse effects produce different reported incidence: patient diaries yielded significantly more adverse effects than other forms of assessment. We recommend guidelines for reporting adverse effect information in clinical trials.

Young men's knowledge of testicular cancer and testicular self-examination: a lost opportunity?

Testicular cancer remains the most commonly occurring cancer in young men (aged 20-45 years) and recent trends suggest an increase throughout the western world. Whilst testicular cancer is highly treatable late diagnosis resulting in poorer treatment outcomes remains a problem. Testicular self-examination (TSE) a procedure whereby young men can routinely systematically examine their testicles has been advocated as a particularly effective health education intervention. This study aimed to establish the knowledge of testicular cancer and prevalence of TSE practice amongst young men. A descriptive survey approach using a 16-item self-report questionnaire was administered to a convenience sample of 203 male undergraduate and postgraduate students at the University of Huddersfield. Results indicated that the majority of the respondents were either uninformed or misinformed about the risks and symptoms of testicular cancer although 78% indicated an interest in accessing information. Only 32% had prior knowledge of TSE, 22% practiced TSE, and worryingly only a single respondent was able to recognize the correct procedure and indicated he regularly practiced TSE. Sixty-eight per cent indicated that TSE should be a part of general health assessments for men. Although some critics of TSE argue the cost of teaching TSE outweighs the benefits in terms of early diagnosis this study suggests that young men may be willing to participate in an aspect of personal health surveillance. If this is the case then low cost strategies to increase impact on the target audience should be considered.