Incomplete evidence: the inadequacy of databases in tracing published adverse drug reactions in clinical trials

Pharmacogenomic Determinants of Adverse Drug Effects: A Systematic Review and Meta-analysis

BACKGROUND/AIM

Genomic variants can predispose individuals to adverse drug effects (ADEs), implying the potential for personalised therapy based on genetic data to prevent them. However, existing pharmacogenomic databases lack a comprehensive list of such variants due to irregular updates and incomplete literature coverage. To facilitate the assessment of the feasibility of using pharmacogenetic testing on a larger scale and identify existing gaps in the literature, this study sought to compile a comprehensive list of genomic variants associated with ADEs, with a focus on serious ADEs.

PATIENTS AND METHODS

To identify relevant pharmacogenetic studies within randomised controlled trials (RCTs), post-hoc studies of RCTs and meta-analyses, two literature searches were performed across multiple databases. The compiled list of variants associated with ADEs was refined to create a set of variant-drug pairs significantly associated with serious ADEs.

RESULTS

We identified 254 RCTs/post-hoc studies and 207 meta-analyses investigating variants associated with ADEs. Among the 254 RCTs/post-hoc studies identified, 24 meta-analyses were conducted. Among these, only G6PD A- showed a significant association with severe anaemia in patients receiving artemisinin-based treatment for malaria.

CONCLUSION

This systematic review provides a comprehensive list of variants associated with ADEs and a set of variant-drug pairs significantly associated with serious ADEs. These resources serve as valuable references for regulatory agencies, researchers, and healthcare professionals. This study, however, underscores the need for improved indexing and standardised definitions of ADE seriousness in the literature.

Adverse Events Reported in Trials Assessing Manual Therapy to the Extremities: A Systematic Review

Objective: This review aimed to describe the quality and comprehensiveness of adverse event (AE) reporting in clinical trials incorporating manual therapy (MT) as an intervention for extremity conditions using the Consolidated Standards of Reporting Trials (CONSORT)-Harms extension as the benchmark. The secondary aim was to determine whether the quality of AE reporting improved after the availability of the CONSORT reporting checklist. Design: Systematic review. Methods: A literature search was conducted using multiple databases to identify trials where MT was used to treat extremity conditions. Studies that reported AEs were identified and evaluated using the CONSORT-Harms extension. The frequency of trials reporting study AEs before and after the publication of the updated 2010 CONSORT statement was calculated, along with the categorization of how study AEs were reported. Results: Of the 55,539 studies initially identified, 220 trials met all inclusion criteria. Eighty trials (36.4%) reported AE occurrence. None of the studies that reported AEs adhered to all 10 criteria proposed by the 2010 CONSORT-Harms extension. The most commonly reported criterion was number four, which clarified how AE-related information was collected (30% of trials). The least reported criterion was number six, which describes the participant withdrawals for each arm due to AEs and the experience with the allocated treatment (1.3% of trials). The nomenclature used to describe AEs varied substantially. Fifty-nine of 76 trials (33.3%) were published after the updated CONSORT Harms-checklist was available, compared to 21 of 44 trials (46.7%) published before it was available. Conclusion: Reporting of AEs in trials investigating MT for extremity conditions is poor. Every included trial lacked adherence to all 10 criteria proposed by the CONSORT-Harms Extension. The quality and comprehensiveness of AE reporting did not improve after the most recent CONSORT update recommending AE reporting. Clinicians must obtain informed consent before performing any intervention, including MT, which requires disclosing potential risks, which could be better known with improved tracking, analyzing, and reporting of AEs. The authors recommend improved adherence to best practices for adequately tracking and reporting AEs in future MT trials.

Accurate and interpretable drug-drug interaction prediction enabled by knowledge subgraph learning

BACKGROUND

Discovering potential drug-drug interactions (DDIs) is a long-standing challenge in clinical treatments and drug developments. Recently, deep learning techniques have been developed for DDI prediction. However, they generally require a huge number of samples, while known DDIs are rare.

METHODS

In this work, we present KnowDDI, a graph neural network-based method that addresses the above challenge. KnowDDI enhances drug representations by adaptively leveraging rich neighborhood information from large biomedical knowledge graphs. Then, it learns a knowledge subgraph for each drug-pair to interpret the predicted DDI, where each of the edges is associated with a connection strength indicating the importance of a known DDI or resembling strength between a drug-pair whose connection is unknown. Thus, the lack of DDIs is implicitly compensated by the enriched drug representations and propagated drug similarities.

RESULTS

Here we show the evaluation results of KnowDDI on two benchmark DDI datasets. Results show that KnowDDI obtains the state-of-the-art prediction performance with better interpretability. We also find that KnowDDI suffers less than existing works given a sparser knowledge graph. This indicates that the propagated drug similarities play a more important role in compensating for the lack of DDIs when the drug representations are less enriched.

CONCLUSIONS

KnowDDI nicely combines the efficiency of deep learning techniques and the rich prior knowledge in biomedical knowledge graphs. As an original open-source tool, KnowDDI can help detect possible interactions in a broad range of relevant interaction prediction tasks, such as protein-protein interactions, drug-target interactions and disease-gene interactions, eventually promoting the development of biomedicine and healthcare.

Drug Repurposing Using FDA Adverse Event Reporting System (FAERS) Database

Drug repurposing is an emerging approach to reassigning existing pre-approved therapies for new indications. The FDA Adverse Event Reporting System (FAERS) is a large database of over 28 million adverse event reports submitted by medical providers, patients, and drug manufacturers and provides extensive drug safety signal data. In this review, four common drug repurposing strategies using FAERS are described, including inverse signal detection for a single disease, drug-drug interactions that mitigate a target ADE, identifying drug-ADE pairs with opposing gene perturbation signatures and identifying drug-drug pairs with congruent gene perturbation signatures. The purpose of this review is to provide an overview of these different approaches using existing successful applications in the literature. With the fast expansion of adverse drug event reports, FAERS-based drug repurposing represents a promising strategy for discovering new uses for existing therapies.

Cholinesterase inhibitors and falls, syncope and injuries in patients with cognitive impairment: a systematic review and meta-analysis

BACKGROUND

Cholinesterase inhibitors are commonly used to treat patients with neurocognitive disorders, who often have an elevated risk of falling. Effective use of these medications requires a thoughtful assessment of risks and benefits.

OBJECTIVE

To provide an update on previous reviews and determine the association between cholinesterase inhibitors and falls, syncope, fracture and accidental injuries in patients with neurocognitive disorders.

METHODS

Embase, MEDLINE, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature and AgeLine were systematically searched through March 2023 to identify all randomised controlled trials of cholinesterase inhibitors (donepezil, galantamine, rivastigmine) in patients with cognitive impairment. Corresponding authors were contacted for additional data necessary for meta-analysis. Inclusion criteria consisted of adults ≥19 years, with a diagnosis of dementia, Parkinson's disease, mild cognitive impairment or traumatic brain injury. Data were extracted in duplicate for the aforementioned primary outcomes and all outcomes were analysed using random-effects meta-analysis.

RESULTS

Fifty three studies (30 donepezil, 14 galantamine, 9 rivastigmine) were included providing data on 25, 399 patients. Cholinesterase inhibitors, compared to placebo, were associated with reduced risk of falls (risk ratio [RR] 0.84 [95% confidence interval [CI] = 0.73-0.96, P = 0.009]) and increased risk of syncope (RR 1.50 [95% CI = 1.02-2.21, P = 0.04]). There was no association with accidental injuries or fractures.

CONCLUSION

In patients with neurocognitive disorders, cholinesterase inhibitors were associated with decreased risk of falls, increased risk of syncope and no association with accidental trauma or fractures. These findings will help clinicians better evaluate risks and benefits of cholinesterase inhibitors.

Identifying the serious clinical outcomes of adverse reactions to drugs by a multi-task deep learning framework

Adverse Drug Reactions (ADRs) have a direct impact on human health. As continuous pharmacovigilance and drug monitoring prove to be costly and time-consuming, computational methods have emerged as promising alternatives. However, most existing computational methods primarily focus on predicting whether or not the drug is associated with an adverse reaction and do not consider the core issue of drug benefit-risk assessment-whether the treatment outcome is serious when adverse drug reactions occur. To this end, we categorize serious clinical outcomes caused by adverse reactions to drugs into seven distinct classes and present a deep learning framework, so-called GCAP, for predicting the seriousness of clinical outcomes of adverse reactions to drugs. GCAP has two tasks: one is to predict whether adverse reactions to drugs cause serious clinical outcomes, and the other is to infer the corresponding classes of serious clinical outcomes. Experimental results demonstrate that our method is a powerful and robust framework with high extendibility. GCAP can serve as a useful tool to successfully address the challenge of predicting the seriousness of clinical outcomes stemming from adverse reactions to drugs.

Quality of adverse event reporting in phase III randomized controlled trials of breast and colorectal cancer: A systematic review

BACKGROUND

Clinical trial reports often emphasize efficacy over harms, leading to misinterpretation of the risk-to-benefit ratio of new therapies. Clear and sufficiently detailed reporting of methods and results is especially important in the abstracts of trial reports, as readers often base their assessment of a trial on such information. In this study, we evaluated the quality of adverse event (AE) reporting and abstract quality in phase III randomized controlled trials (RCTs) of systemic therapies in breast and colorectal cancer.

METHODS

Medline, EMBASE, Cochrane Database of RCTs, and Cochrane Database of Systematic Reviews were searched from November 2005 to September 2018. Phase III RCTs evaluating systemic therapies in breast or colorectal cancer were included. Each article was independently reviewed by two investigators using a standardized data extraction form based on guidelines developed by the Consolidated Standards of Reporting Trials (CONSORT) group. Descriptive statistics, bivariate analysis, and multivariable linear regression were used to analyze data. All statistical tests were two-sided.

RESULTS

Of 166 RCTs identified, 99.4% reported harms in the manuscript body, and 59.6% reported harms in the abstract. Reporting was restricted to severe harms in 15.6% of RCTs. Statistical comparison of AE rates went unreported in 59.0% of studies. Information regarding AEs leading to dose reductions, treatment discontinuations, or study withdrawals went unreported in 59.3%, 18.7%, and 86.8% of studies, respectively. Recently published RCTs (P = .009) and those sponsored at least partially by for-profit companies (P = .003) had higher abstract quality scores.

CONCLUSIONS

Breast and colorectal cancer phase III RCTs inadequately report CONSORT-compliant AE data. Improved guideline adherence and abstract reporting is required to properly weigh benefits and harms of new oncologic therapies.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42019140673.

Efficacy and Safety of Endoscopic Sleeve Gastroplasty: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Bariatric surgery is the most successful treatment for obesity. However, many patients avoid surgery due to its perceived invasive nature and fear of complications. Endoscopic sleeve gastroplasty (ESG) is a seemingly less invasive option for patients with obesity. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of ESG in adults.

METHODS

We searched MEDLINE, Embase, Web of Science, and Cochrane Library through July 2019. Investigated outcomes included the percent total body weight loss (TBWL), body mass index reduction, percent excess weight loss (EWL), and adverse events.

RESULTS

We extracted data from 8 original studies, published from 2016 through 2019, which included a total of 1772 patients. At 6 months, mean TBWL was 15.1% (95% CI, 14.3-16.0), mean decrease in body mass index was 5.65 kg/m2 (95% CI, 5.07-6.22), and mean excess weight loss was 57.7% (95% CI, 52.0-63.4). Weight loss was sustained at 12 months and 18-24 months with a TBWL of 16.5% (95% CI, 15.2-17.8) and 17.2% (95% CI, 14.6-19.7), respectively. The pooled post-ESG rate of severe adverse events was 2.2% (95% CI, 1.6%-3.1%), including pain or nausea requiring hospitalization (n = 18, 1.08%), upper gastrointestinal bleeding (n=9, 0.56%), and peri-gastric leak or fluid collection (n = 8, 0.48%).

CONCLUSIONS

In a systematic review and meta-analysis, we found ESG to produce clinically significant weight loss that was reproducible among independent centers and to have a low rate of severe adverse events. ESG appears to be an effective intervention for patients with obesity, although comparative studies and randomized controlled trials are necessary. PROSPERO Identifier: CRD42019121921.

Safety and effectiveness of balloon cryoablation for treatment of Barrett's associated neoplasia: systematic review and meta-analysis

Background and study aims  Balloon cryoablation (BC) is a novel procedure for endoscopic ablation of Barrett's esophagus (BE- associated neoplasia. We performed a meta-analysis to assess the feasibility, effectiveness, and safety of BC for treatment of BE neoplasia. Patients and methods  Several databases were searched for relevant articles (PubMed, Web of Science, Google Scholar, EMBASE) as well as abstracts of recent gastroenterology meetings. Data extraction was performed by two investigators using standardized forms, including age, gender, length of BE segment, prior treatments, procedural time and number ablation sessions, technical feasibility, adverse events, and eradication rates of intestinal metaplasia (CE-IM) and dysplasia (CE-D) at follow-up. Quality of the studies was assessed using a modified Newcastle Ottawa Scale. Results  Seven studies met inclusion criteria for a total of 548 ablation sessions in 272 patients. The most common histopathology reported prior to BC was high-grade dysplasia (n = 131), followed by low-grade dysplasia (n = 75), and intramucosal adenocarcinoma (n = 52). The pooled rate for technical feasibility was 95.8 % (95 % CI: 93.6-97.5 %; I 2  = 13.2 %; P  = 0.3). Pooled rates of CE-IM and CE-D were 85.8 % (95 % CI: 77.8-92.2 %, I 2  = 55.5 %; p = 0.04) and 93.8 % (95 % CI: 85.5-98.7 %, I 2  = 74.2 %; P  = 0.001), respectively. The overall adverse event (AE) rate was 12.5 % (34 out of 272 patients), of which stricture formation was the most common (5.8 %), followed by mucosal laceration (0.7 %), perforation (0.4 %), and bleeding (0.4 %). All AEs were successfully managed endoscopically. Conclusion  This meta-analysis suggests that BC is a safe and effective ablative technique for treatment of BE neoplasia; future prospective comparative trials are needed to corroborate these initial findings.

Side effects associated with pharmacotherapy for pediatric irritable bowel syndrome and functional abdominal pain - not otherwise specified: a systematic review

INTRODUCTION

To systematically review the literature regarding the side effects of pharmacotherapy in children with irritable bowel syndrome (IBS) and functional abdominal pain - not otherwise specified (FAP-NOS). Areas covered: Cochrane Library, PubMed, and Embase databases were searched from inception to May 2018. The following inclusion criteria were applied: (1) randomized controlled trials (RCTs), cohort studies or case-control studies; (2) in children aged 4-18 years or adult studies if children are reported separately; (3) reporting a diagnosis of IBS or FAP-NOS as defined by the authors; and (4) reporting the occurrence of side effects of pharmacotherapy. Quality assessment of included studies was conducted. Expert opinion: A total of 4619 articles were identified; 17 were included. In 10/17 (59%) studies, side effects of pharmacotherapy (antispasmodics, antidepressants, antihistaminic agents, serotonergic agents and antibiotics) occurred. The majority of side effects were: (1) limited to the gastrointestinal tract and central nervous system and, 2) mild and transient. No serious adverse events were reported. This systematic review shows that data on safety in children with functional abdominal pain disorders are scarce, and highlights the lack of high-quality research for potential side effects of pediatric IBS and FAP-NOS. Further research by means of large well-designed-follow-up studies is necessary.

Serious adverse events reported in placebo randomised controlled trials of oral naltrexone: a systematic review and meta-analysis

BACKGROUND

Naltrexone is an opioid antagonist used in many different conditions, both licensed and unlicensed. It is used at widely varying doses from 3 to 250 mg. The aim of this review was to extensively evaluate the safety of oral naltrexone by examining the risk of serious adverse events and adverse events in randomised controlled trials of naltrexone compared to placebo.

METHODS

A systematic search of the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, other databases and clinical trials registries was undertaken up to May 2018. Parallel placebo-controlled randomised controlled trials longer than 4 weeks published after 1 January 2001 of oral naltrexone at any dose were selected. Any condition or age group was included, excluding only studies in opioid or ex-opioid users owing to possible opioid/opioid antagonist interactions. The systematic review used the guidance of the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-analyses harms checklist throughout. Numerical data were independently extracted by two people and cross-checked. Risk of bias was assessed with the Cochrane risk-of-bias tool. Meta-analyses were performed in R using random effects models throughout.

RESULTS

Eighty-nine randomised controlled trials with 11,194 participants were found, studying alcohol use disorders (n = 38), various psychiatric disorders (n = 13), impulse control disorders (n = 9), other addictions including smoking (n = 18), obesity or eating disorders (n = 6), Crohn's disease (n = 2), fibromyalgia (n = 1) and cancers (n = 2). Twenty-six studies (4,960 participants) recorded serious adverse events occurring by arm of study. There was no evidence of increased risk of serious adverse events for naltrexone compared to placebo (risk ratio 0.84, 95% confidence interval 0.66-1.06). Sensitivity analyses pooling risk differences supported this conclusion (risk difference -0.01, 95% confidence interval -0.02-0.00) and subgroup analyses showed that results were consistent across different doses and disease groups. Secondary analysis revealed only six marginally significant adverse events for naltrexone compared to placebo, which were of mild severity.

CONCLUSIONS

Naltrexone does not appear to increase the risk of serious adverse events over placebo. These findings confirm the safety of oral naltrexone when used in licensed indications and encourage investments to undertake efficacy studies in unlicensed indications.

TRIAL REGISTRATION

PROSPERO 2017 CRD42017054421 .

Endoscopic submucosal dissection for early Barrett's neoplasia: a meta-analysis

BACKGROUND AND AIMS

The role of endoscopic submucosal dissection (ESD) in Barrett's esophagus (BE) is not well established. This meta-analysis aimed to evaluate the safety and efficacy of ESD for the management of early BE neoplasia.

METHODS

Three online databases were searched. The Cochran Q test and I² were used to test for heterogeneity. Pooling was conducted using either fixed- or random-effects models depending on heterogeneity across studies. For the main outcomes, potential sources of heterogeneity were evaluated via linear regression analysis.

RESULTS

Eleven studies (501 patients, 524 lesions) were included. Mean lesion size was 27 mm (95% confidence interval [CI], 20.9-33.1). Pooled estimate for en bloc resection was 92.9% (95% CI, 90.3%-95.2%). The pooled R0 (complete) and curative resection rates were 74.5% (95% CI, 66.3%-81.9%) and 64.9% (95% CI, 55.7%-73.6%), respectively. There was no association between R0 or curative resection rates and study setting (Asia vs West), length of BE, lesion characteristics, procedural time, or length of follow-up. The pooled estimates for perforation and bleeding were 1.5% (95% CI, .4%-3.0%) and 1.7% (95% CI, .6%-3.4%), respectively. Esophageal stricture rate was 11.6% (95% CI, .9%-29.6%). Incidence of recurrence after curative resection was .17% (95% CI, 0%-.3%) at a mean follow-up 22.9 months (95% CI, 17.5-28.3).

CONCLUSIONS

ESD for early BE neoplasia is associated with a high en bloc resection rate, acceptable safety profile, and low recurrence after curative resection. ESD should be considered as part of the armamentarium for the management of BE neoplasia.

The feasibility of a search filter for the adverse effects of nondrug interventions in MEDLINE and Embase

Authors and indexers are increasingly including terms for adverse drug effects in the titles, abstracts, or indexing of records in MEDLINE and Embase. However, it is not clear if this is the same for studies with nondrug adverse effects data. We therefore assessed the feasibility of using adverse effects terms when searching MEDLINE or Embase to retrieve papers of nondrug adverse effects. A collection of papers that reported data on nondrug adverse effects was sought from included studies of systematic reviews. Each included study was analysed to ascertain whether the corresponding record in MEDLINE and Embase included adverse effects terms in the title, abstract, or indexing. From 9129 records screened from DARE, 30 reviews evaluating nondrug adverse effects met our inclusion criteria. From these, 635 unique papers were included in our analysis. Sensitive searches for adverse effects required generic and specific named adverse effects terms using the title, abstract, and indexing. Records relating to surgical interventions were more likely to contain adverse effects terms than records relating to nonsurgical interventions. Using any adverse effects terms in the title, abstract or indexing in MEDLINE and Embase would have identified an average of 94% of papers on surgical adverse effect interventions per systematic review and 72% of papers on nonsurgical adverse effects per systematic review. Hence, while a generic nondrug adverse effect search filter may not yet be feasible, a filter for the adverse effects of surgical interventions may be within reach.

Effectiveness of adverse effects search filters: drugs versus medical devices

OBJECTIVE

The study tested the performance of adverse effects search filters when searching for safety information on medical devices, procedures, and diagnostic tests in MEDLINE and Embase.

METHODS

The sensitivity of 3 filters was determined using a sample of 631 references from 131 rapid reviews related to the safety of health technologies. The references were divided into 2 sets by type of intervention: drugs and nondrug health technologies. Keyword and indexing analysis were performed on references from the nondrug testing set that 1 or more of the filters did not retrieve.

RESULTS

For all 3 filters, sensitivity was lower for nondrug health technologies (ranging from 53%-87%) than for drugs (88%-93%) in both databases. When tested on the nondrug health technologies set, sensitivity was lower in Embase (ranging from 53%-81%) than in MEDLINE (67%-87%) for all filters. Of the nondrug records that 1 or more of the filters missed, 39% of the missed MEDLINE records and 18% of the missed Embase records did not contain any indexing terms related to adverse events. Analyzing the titles and abstracts of nondrug records that were missed by any 1 filter, the most commonly used keywords related to adverse effects were: risk, complications, mortality, contamination, hemorrhage, and failure.

CONCLUSIONS

In this study, adverse effects filters were less effective at finding information about the safety of medical devices, procedures, and tests compared to information about the safety of drugs.

Topical analgesics for acute and chronic pain in adults - an overview of Cochrane Reviews

BACKGROUND

Topical analgesic drugs are used for a variety of painful conditions. Some are acute, typically strains or sprains, tendinopathy, or muscle aches. Others are chronic, typically osteoarthritis of hand or knee, or neuropathic pain.

OBJECTIVES

To provide an overview of the analgesic efficacy and associated adverse events of topical analgesics (primarily nonsteroidal anti-inflammatory drugs (NSAIDs), salicylate rubefacients, capsaicin, and lidocaine) applied to intact skin for the treatment of acute and chronic pain in adults.

METHODS

We identified systematic reviews in acute and chronic pain published to February 2017 in the Cochrane Database of Systematic Reviews (the Cochrane Library). The primary outcome was at least 50% pain relief (participant-reported) at an appropriate duration. We extracted the number needed to treat for one additional beneficial outcome (NNT) for efficacy outcomes for each topical analgesic or formulation, and the number needed to treat for one additional harmful outcome (NNH) for adverse events. We also extracted information on withdrawals due to lack of efficacy or adverse events, systemic and local adverse events, and serious adverse events. We required information from at least 200 participants, in at least two studies. We judged that there was potential for publication bias if the addition of four studies of typical size (400 participants) with zero effect increased NNT compared with placebo to 10 (minimal clinical utility). We extracted GRADE assessment in the original papers, and made our own GRADE assessment.

MAIN RESULTS

Thirteen Cochrane Reviews (206 studies with around 30,700 participants) assessed the efficacy and harms from a range of topical analgesics applied to intact skin in a number of acute and chronic painful conditions. Reviews were overseen by several Review Groups, and concentrated on evidence comparing topical analgesic with topical placebo; comparisons of topical and oral analgesics were rare.For at least 50% pain relief, we considered evidence was moderate or high quality for several therapies, based on the underlying quality of studies and susceptibility to publication bias.In acute musculoskeletal pain (strains and sprains) with assessment at about seven days, therapies were diclofenac Emulgel (78% Emulgel, 20% placebo; 2 studies, 314 participants, NNT 1.8 (95% confidence interval 1.5 to 2.1)), ketoprofen gel (72% ketoprofen, 33% placebo, 5 studies, 348 participants, NNT 2.5 (2.0 to 3.4)), piroxicam gel (70% piroxicam, 47% placebo, 3 studies, 522 participants, NNT 4.4 (3.2 to 6.9)), diclofenac Flector plaster (63% Flector, 41% placebo, 4 studies, 1030 participants, NNT 4.7 (3.7 to 6.5)), and diclofenac other plaster (88% diclofenac plaster, 57% placebo, 3 studies, 474 participants, NNT 3.2 (2.6 to 4.2)).In chronic musculoskeletal pain (mainly hand and knee osteoarthritis) therapies were topical diclofenac preparations for less than six weeks (43% diclofenac, 23% placebo, 5 studies, 732 participants, NNT 5.0 (3.7 to 7.4)), ketoprofen over 6 to 12 weeks (63% ketoprofen, 48% placebo, 4 studies, 2573 participants, NNT 6.9 (5.4 to 9.3)), and topical diclofenac preparations over 6 to 12 weeks (60% diclofenac, 50% placebo, 4 studies, 2343 participants, NNT 9.8 (7.1 to 16)). In postherpetic neuralgia, topical high-concentration capsaicin had moderate-quality evidence of limited efficacy (33% capsaicin, 24% placebo, 2 studies, 571 participants, NNT 11 (6.1 to 62)).We judged evidence of efficacy for other therapies as low or very low quality. Limited evidence of efficacy, potentially subject to publication bias, existed for topical preparations of ibuprofen gels and creams, unspecified diclofenac formulations and diclofenac gel other than Emulgel, indomethacin, and ketoprofen plaster in acute pain conditions, and for salicylate rubefacients for chronic pain conditions. Evidence for other interventions (other topical NSAIDs, topical salicylate in acute pain conditions, low concentration capsaicin, lidocaine, clonidine for neuropathic pain, and herbal remedies for any condition) was very low quality and typically limited to single studies or comparisons with sparse data.We assessed the evidence on withdrawals as moderate or very low quality, because of small numbers of events. In chronic pain conditions lack of efficacy withdrawals were lower with topical diclofenac (6%) than placebo (9%) (11 studies, 3455 participants, number needed to treat to prevent (NNTp) 26, moderate-quality evidence), and topical salicylate (2% vs 7% for placebo) (5 studies, 501 participants, NNTp 21, very low-quality evidence). Adverse event withdrawals were higher with topical capsaicin low-concentration (15%) than placebo (3%) (4 studies, 477 participants, NNH 8, very low-quality evidence), topical salicylate (5% vs 1% for placebo) (7 studies, 735 participants, NNH 26, very low-quality evidence), and topical diclofenac (5% vs 4% for placebo) (12 studies, 3552 participants, NNH 51, very low-quality evidence).In acute pain, systemic or local adverse event rates with topical NSAIDs (4.3%) were no greater than with topical placebo (4.6%) (42 studies, 6740 participants, high quality evidence). In chronic pain local adverse events with topical capsaicin low concentration (63%) were higher than topical placebo (5 studies, 557 participants, number needed to treat for harm (NNH) 2.6), high quality evidence. Moderate-quality evidence indicated more local adverse events than placebo in chronic pain conditions with topical diclofenac (NNH 16) and local pain with topical capsaicin high-concentration (NNH 16). There was moderate-quality evidence of no additional local adverse events with topical ketoprofen over topical placebo in chronic pain. Serious adverse events were rare (very low-quality evidence).GRADE assessments of moderate or low quality in some of the reviews were considered by us to be very low because of small numbers of participants and events.

AUTHORS' CONCLUSIONS

There is good evidence that some formulations of topical diclofenac and ketoprofen are useful in acute pain conditions such as sprains or strains, with low (good) NNT values. There is a strong message that the exact formulation used is critically important in acute conditions, and that might also apply to other pain conditions. In chronic musculoskeletal conditions with assessments over 6 to 12 weeks, topical diclofenac and ketoprofen had limited efficacy in hand and knee osteoarthritis, as did topical high-concentration capsaicin in postherpetic neuralgia. Though NNTs were higher, this still indicates that a small proportion of people had good pain relief.Use of GRADE in Cochrane Reviews with small numbers of participants and events requires attention.

Assignment of adverse event indexing terms in randomized clinical trials involving spinal manipulative therapy: an audit of records in MEDLINE and EMBASE databases

Background

Reporting of adverse events in randomized clinical trials (RCTs) is encouraged by the authors of The Consolidated Standards of Reporting Trials (CONSORT) statement. With robust methodological design and adequate reporting, RCTs have the potential to provide useful evidence on the incidence of adverse events associated with spinal manipulative therapy (SMT). During a previous investigation, it became apparent that comprehensive search strategies combining text words with indexing terms was not sufficiently sensitive for retrieving records that were known to contain reports on adverse events. The aim of this analysis was to compare the proportion of articles containing data on adverse events associated with SMT that were indexed in MEDLINE and/or EMBASE and the proportion of those that included adverse event-related words in their title or abstract.

Methods

A sample of 140 RCT articles previously identified as containing data on adverse events associated with SMT was used. Articles were checked to determine if: (1) they had been indexed with relevant terms describing adverse events in the MEDLINE and EMBASE databases; and (2) they mentioned adverse events (or any related terms) in the title or abstract.

Results

Of the 140 papers, 91% were MEDLINE records, 85% were EMBASE records, 81% were found in both MEDLINE and EMBASE records, and 4% were not in either database. Only 19% mentioned adverse event-related text words in the title or abstract. There was no significant difference between MEDLINE and EMBASE records in the proportion of available papers (p = 0.078). Of the 113 papers that were found in both MEDLINE and EMBASE records, only 3% had adverse event-related indexing terms assigned to them in both databases, while 81% were not assigned an adverse event-related indexing term in either database.

Conclusions

While there was effective indexing of RCTs involving SMT in the MEDLINE and EMBASE databases, there was a failure of allocation of adverse event indexing terms in both databases. We recommend the development of standardized definitions and reporting tools for adverse events associated with SMT. Adequate reporting of adverse events associated with SMT will facilitate accurate indexing of these types of manuscripts in the databases.

The reporting of adverse events following spinal manipulation in randomized clinical trials-a systematic review

BACKGROUND CONTEXT

Spinal manipulative therapy (SMT) is commonly used to treat spinal disorders. Although clinical practice guidelines recommend the use of SMT in the treatment of neck and back disorders, concerns exist about the nature and incidence of adverse events associated with the intervention. Comprehensive reporting of adverse events in clinical trials could allow for accurate incidence estimates through meta-analysis. However, it is not clear if randomized clinical trials (RCTs) that involve SMT are currently reporting adverse events adequately.

PURPOSE

This study aimed to describe the extent of adverse events reporting in published RCTs involving SMT, and to determine whether the quality of reporting has improved since publication of the 2010 Consolidated Standards Of Reporting Trials (CONSORT) statement.

STUDY DESIGN

This is a systematic literature review.

METHODS

The Physiotherapy Evidence Database (PEDro) and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for RCTs involving SMT. Domains of interest included classifications of adverse events, completeness of adverse events reporting, nomenclature used to describe the events, methodological quality of the study, and details of the publishing journal. Data were analyzed using descriptive statistics. Frequencies and proportions of trials reporting on each of the specified domains above were calculated. Differences in proportions between pre- and post-CONSORT trials were calculated with 95% confidence intervals using standard methods, and statistical comparisons were analyzed using tests for equality of proportions with continuity correction. There was no funding obtained for this study. The authors declare no conflict of interest.

RESULTS

Of 7,398 records identified in the electronic searches, 368 articles were eligible for inclusion in this review. Adverse events were reported in 140 (38.0%) articles. There was a significant increase in the reporting of adverse events post-CONSORT (p=.001). There were two major adverse events reported (0.3%). Only 22 articles (15.7%) reported on adverse events in the abstract. There were no differences in reporting of adverse events post-CONSORT for any of the chosen parameters.

CONCLUSIONS

Although there has been an increase in reporting adverse events since the introduction of the 2010 CONSORT guidelines, the current level should be seen as inadequate and unacceptable. We recommend that authors adhere to the CONSORT statement when reporting adverse events associated with RCTs that involve SMT.

Efficacy and adverse events of cold vs hot polypectomy: A meta-analysis

AIM: To compare previously reported randomized controlled studies (RCTs) of cold and hot polypectomy, we systematically reviewed and clarify the utility of cold polypectomy over hot with respect to efficacy and adverse events.

METHODS: A meta-analysis was conducted to evaluate the predominance of cold and hot polypectomy for removing colon polyps. Published articles and abstracts from worldwide conferences were searched using the keywords “cold polypectomy”. RCTs that compared either or both the effects or adverse events of cold polypectomy with those of hot polypectomy were collected. The patients’ demographics, endoscopic procedures, No. of examined lesions, lesion size, macroscopic and histologic findings, rates of incomplete resection, bleeding amount, perforation, and length of procedure were extracted from each study. A forest plot analysis was used to verify the relative strength of the effects and adverse events of each procedure. A funnel plot was generated to assess the possibility of publication bias.

RESULTS: Ultimately, six RCTs were selected. No significant differences were noted in the average lesion size (less than 10 mm) between the cold and hot polypectomy groups in each study. Further, the rates of complete resection and adverse events, including delayed bleeding, did not differ markedly between cold and hot polypectomy. The average procedural time in the cold polypectomy group was significantly shorter than in the hot polypectomy group.

CONCLUSION: Cold polypectomy is a time-saving procedure for removing small polyps with markedly similar curability and safety to hot polypectomy.

Antiepileptic drugs' tolerability and safety--a systematic review and meta-analysis of adverse effects in dogs

Background

The safety profile of anti-epileptic drugs (AEDs) is an important consideration for the regulatory bodies, owners and prescribing clinicians. Information on their adverse effects still remains limited. A systematic review including a meta-analytic approach was designed to evaluate existing evidence for the safety profile of AEDs in canine patients. Electronic searches of PubMed, CAB Direct and Google scholar were carried out without date or language restrictions. Conference proceedings were also searched. Peer-reviewed full-length studies reporting adverse effects of AEDs in epileptic and healthy non-epileptic dogs were included. Studies were allocated to three groups based on their design. Individual studies were evaluated based on the quality of evidence (study design, study group sizes, subject enrolment quality and overall risk of bias) and the outcome measures reported (proportion of specific adverse effects for each AED, prevalence and 95 % confidence interval of the affected population in each study and comparative odds ratio of adverse effects for AEDs).

Results

Ninety studies, including six conference proceedings, reporting clinical outcomes of AEDs’ adverse effects were identified. Few studies were designed as blinded randomised controlled clinical trials. Many studies included low canine populations with unclear criteria of subject enrolment and short treatment periods. Direct comparisons suggested that imepitoin and levetiracetam might have a better safety profile than phenobarbital, whilst the latter might have a better safety profile than potassium bromide. However, none of these comparisons showed a statistically significant difference. Comparisons between other AEDs were not possible as a considerable amount of studies lacked power calculations or adequate data to allow further statistical analysis. Individual AED assessments indicated that levetiracetam might be one of the safest AEDs, followed by imepitoin and then phenobarbital and potassium bromide; these findings were all supported by a strong level of evidence. The safety profile in other AEDs was variable, but weak evidence was found to permit firm conclusions or to compare their safety to other AEDs.

Conclusions

This systematic review provides objective evaluation of the most commonly used AEDs’ adverse effects. Adverse effects usually appeared mild in all AEDs and subsided once doses and/or serum levels were monitored or after the AED was withdrawn. Although phenobarbital might be less safe than imepitoin and levetiracetam, there was insufficient evidence to classify it as an AED with a high risk of major adverse effects. It is important for clinicians to evaluate both AEDs’ effectiveness and safety on an individual basis before the selection of the appropriate monotherapy or adjunctive AED therapy.

Toward standardized reporting of drug interactions: the READI checklist for anecdotal reports

Anecdotal reports contribute 30% of the literature on adverse drug reactions and interactions. However, the quality of such reports has not been uniformly high. Standardized reporting of clinical studies is of increasing interest, including the CARE guidelines on reporting anecdotal cases in general. Although there are guidelines on evaluating and managing drug-drug interactions, there are none recommending methods for reporting suspected drug interactions. Here, based on published guidelines for reporting suspected adverse drug reactions, I propose a checklist for reporting details of suspected drug interactions, the REporting Anecdotal Drug Interactions (READI) checklist, hoping to stimulate discussion and improve reporting of suspected drug interactions. The checklist includes items relating, among others, to the patient affected, the drugs involved, and the outcome.

Bisphosphonates and risk of cardiovascular events: a meta-analysis

Background and Objectives

Some evidence suggests that bisphosphonates may reduce atherosclerosis, while concerns have been raised about atrial fibrillation. We conducted a meta-analysis to determine the effects of bisphosphonates on total adverse cardiovascular (CV) events, atrial fibrillation, myocardial infarction (MI), stroke, and CV death in adults with or at risk for low bone mass.

Methods

A systematic search of MEDLINE and EMBASE through July 2014 identified 58 randomized controlled trials with longer than 6 months in duration that reported CV events. Absolute risks and the Mantel-Haenszel fixed-effects odds ratios (ORs) and 95% confidence intervals (CIs) of total CV events, atrial fibrillation, MI, stroke, and CV death were estimated. Subgroup analyses by follow-up duration, population characteristics, bisphosphonate types, and route were performed.

Results

Absolute risks over 25–36 months in bisphosphonate-treated versus control patients were 6.5% versus 6.2% for total CV events; 1.4% versus 1.5% for atrial fibrillation; 1.0% versus 1.2% for MI; 1.6% versus 1.9% for stroke; and 1.5% versus 1.4% for CV death. Bisphosphonate treatment up to 36 months did not have any significant effects on total CV events (14 trials; ORs [95% CI]: 0.98 [0.84–1.14]; I² = 0.0%), atrial fibrillation (41 trials; 1.08 [0.92–1.25]; I² = 0.0%), MI (10 trials; 0.96 [0.69–1.34]; I² = 0.0%), stroke (10 trials; 0.99 [0.82–1.19]; I² = 5.8%), and CV death (14 trials; 0.88 [0.72–1.07]; I² = 0.0%) with little between-study heterogeneity. The risk of atrial fibrillation appears to be modestly elevated for zoledronic acid (6 trials; 1.24 [0.96–1.61]; I² = 0.0%), not for oral bisphosphonates (26 trials; 1.02 [0.83–1.24]; I² = 0.0%). The CV effects did not vary by subgroups or study quality.

Conclusions

Bisphosphonates do not have beneficial or harmful effects on atherosclerotic CV events, but zoledronic acid may modestly increase the risk of atrial fibrillation. Given the large reduction in fractures with bisphosphonates, changes in osteoporosis treatment decision due to CV risk are not justified.

Efficacy and adverse events of EMR and endoscopic submucosal dissection for the treatment of colon neoplasms: a meta-analysis of studies comparing EMR and endoscopic submucosal dissection

BACKGROUND

EMR and endoscopic submucosal dissection (ESD) are used frequently to remove colon neoplasms. However, the predominance of these procedures has not yet been thoroughly explored.

OBJECTIVE

To compare the efficacy and adverse events related to EMR with those related to ESD for colon neoplasms.

DESIGN

A meta-analysis of 8 studies published between 2005 and 2013.

SETTING

Multicenter review.

PATIENTS

Patients from 8 studies yielding 2299 lesions.

INTERVENTIONS

EMR or ESD.

MAIN OUTCOME MEASUREMENTS

En bloc resection, curative resection, recurrence, and adverse events.

RESULTS

The pooled odds ratios (OR) (OR [95% confidence interval]) for the tumor size, length of the procedure, en bloc resection, curative resection, recurrence, additional surgery, delayed bleeding, and perforation by ESD versus EMR were 7.38 (6.42-8.34), 58.07 (36.27-79.88), 6.84 (3.30-14.18), 4.26 (3.77-6.57), 0.08 (0.04-0.17), 2.16 (1.16-4.03), 0.85 (0.45-1.60), and 4.96 (2.79-8.85), respectively.

LIMITATIONS

This analysis included only nonrandomized studies.

CONCLUSION

The size of the tumor and rate of en bloc resection and curative resection were higher, and the rate of recurrence was lower in the ESD group versus the EMR group. However, in the ESD group, the procedure was longer, and the rate of additional surgery and perforation was higher, suggesting that the indications for ESD should therefore be rigorously determined in order to avoid such problems.

Failure or success of search strategies to identify adverse effects of medical devices: a feasibility study using a systematic review

BACKGROUND

Research has indicated that adverse effects terms are increasingly prevalent in the title, abstract or indexing terms of articles that contain adverse drug effects data in MEDLINE and Embase. However, it is unknown whether adverse effects terms are present in the database records of articles that contain adverse effects data of medical devices, and thus, to what extent the development of an adverse effects search filter for medical devices may be feasible.

METHODS

A case study systematic review of a medical device was selected. The included studies from a systematic review of the safety of recombinant human bone morphogenetic protein-2 (rhBMP-2) for spinal fusion were used in the analysis. For each included study, the corresponding database record on MEDLINE and Embase was assessed to measure the presence or absence of adverse effects terms in the title, abstract or indexing. The performance of each potential adverse effects search term was also measured and compared.

RESULTS

There were 82 publications (49 studies) included in the systematic review with 51 of these indexed on MEDLINE and 55 on Embase. Ninety-four percent (48/51) of the records on MEDLINE and 95% (52/55) of the records on Embase contained at least one adverse effects related search term. The wide variety of adverse effects terms included in the title, abstract or indexing of bibliographic records, and the lack of any individual high-performing search terms suggests that a combination of terms in different fields is required to identify adverse effects of medical devices. In addition, the most successful search terms differed from the most successful terms for identifying adverse drug effects.

CONCLUSIONS

The search filters currently available for adverse drug effects are not necessarily useful for searching adverse effects data of medical devices. The presence of adverse effects terms in the bibliographic records of articles on medical devices, however, indicates that combinations of adverse effects search terms may be useful in search strategies in MEDLINE and Embase. The results, therefore, suggest that not only a search filter for the adverse effects of medical devices is feasible, but also that it should be a research priority.

Comprehensive evaluations of the adverse effects of drugs: importance of appropriate study selection and data sources

While systematic reviews and meta-analyses are at the top of the evidence hierarchy, most of the methodology has focused on assessing treatment benefit. Hence, we propose a structured framework for the initial steps of searching and identifying relevant data sources so that adverse effects can be evaluated in a comprehensive, unbiased manner. The unique methodological challenges stem from the difficulties of addressing diverse outcomes encompassing common, mild symptoms to rare, fatal events. Retrieval of the most appropriate studies should be specifically tailored to fit the nature of the adverse effects, according to the primary objective and study question. In our framework, the structure of the review takes different forms depending on whether the main aim is on scoping/hypothesis generation, or evaluating statistically the magnitude of risk (hypothesis testing), or clarifying characteristics and risk factors of the adverse effect. The wide range of data sources covering adverse effects all have distinct strengths and limitations, and selection of appropriate sources depends on characteristics of the adverse effect (e.g. background incidence and effect size of the drug, clinical presentation, time of onset after drug exposure). Reviewers need to retrieve particular study designs that are most likely to yield robust data on the adverse effects of interest, rather than rely on studies that cannot reliably detect adverse effects, and may yield 'false negatives'. Type II errors (a particular problem when evaluating rare adverse effects) can lull us into a false sense of security (e.g. wrongly concluding that there was no significant difference in harm between drug and control, with the drug erroneously judged as safe). Given the rapid rate at which methodological improvements occur, this proposed framework is by no means definitive, but aims to stimulate further debate and discussion amongst the pharmacoepidemiological and systematic review communities to reach a common consensus on the best methods.

Automatic construction of a large-scale and accurate drug-side-effect association knowledge base from biomedical literature

Systems approaches to studying drug-side-effect (drug-SE) associations are emerging as an active research area for drug target discovery, drug repositioning, and drug toxicity prediction. However, currently available drug-SE association databases are far from being complete. Herein, in an effort to increase the data completeness of current drug-SE relationship resources, we present an automatic learning approach to accurately extract drug-SE pairs from the vast amount of published biomedical literature, a rich knowledge source of side effect information for commercial, experimental, and even failed drugs. For the text corpus, we used 119,085,682 MEDLINE sentences and their parse trees. We used known drug-SE associations derived from US Food and Drug Administration (FDA) drug labels as prior knowledge to find relevant sentences and parse trees. We extracted syntactic patterns associated with drug-SE pairs from the resulting set of parse trees. We developed pattern-ranking algorithms to prioritize drug-SE-specific patterns. We then selected a set of patterns with both high precisions and recalls in order to extract drug-SE pairs from the entire MEDLINE. In total, we extracted 38,871 drug-SE pairs from MEDLINE using the learned patterns, the majority of which have not been captured in FDA drug labels to date. On average, our knowledge-driven pattern-learning approach in extracting drug-SE pairs from MEDLINE has achieved a precision of 0.833, a recall of 0.407, and an F1 of 0.545. We compared our approach to a support vector machine (SVM)-based machine learning and a co-occurrence statistics-based approach. We show that the pattern-learning approach is largely complementary to the SVM- and co-occurrence-based approaches with significantly higher precision and F1 but lower recall. We demonstrated by correlation analysis that the extracted drug side effects correlate positively with both drug targets, metabolism, and indications.

Comparison of search strategies in systematic reviews of adverse effects to other systematic reviews

BACKGROUND

Research indicates that the methods used to identify data for systematic reviews of adverse effects may need to differ from other systematic reviews.

OBJECTIVES

To compare search methods in systematic reviews of adverse effects with other reviews.

METHODS

The search methodologies in 849 systematic reviews of adverse effects were compared with other reviews.

RESULTS

Poor reporting of search strategies is apparent in both systematic reviews of adverse effects and other types of systematic reviews. Systematic reviews of adverse effects are less likely to restrict their searches to MEDLINE or include only randomised controlled trials (RCTs). The use of other databases is largely dependent on the topic area and the year the review was conducted, with more databases searched in more recent reviews. Adverse effects search terms are used by 72% of reviews and despite recommendations only two reviews report using floating subheadings.

CONCLUSIONS

The poor reporting of search strategies in systematic reviews is universal, as is the dominance of searching MEDLINE. However, reviews of adverse effects are more likely to include a range of study designs (not just RCTs) and search beyond MEDLINE.

dRiskKB: a large-scale disease-disease risk relationship knowledge base constructed from biomedical text

BACKGROUND

Discerning the genetic contributions to complex human diseases is a challenging mandate that demands new types of data and calls for new avenues for advancing the state-of-the-art in computational approaches to uncovering disease etiology. Systems approaches to studying observable phenotypic relationships among diseases are emerging as an active area of research for both novel disease gene discovery and drug repositioning. Currently, systematic study of disease relationships on a phenome-wide scale is limited due to the lack of large-scale machine understandable disease phenotype relationship knowledge bases. Our study innovates a semi-supervised iterative pattern learning approach that is used to build an precise, large-scale disease-disease risk relationship (D1 → D2) knowledge base (dRiskKB) from a vast corpus of free-text published biomedical literature.

RESULTS

21,354,075 MEDLINE records comprised the text corpus under study. First, we used one typical disease risk-specific syntactic pattern (i.e. "D1 due to D2") as a seed to automatically discover other patterns specifying similar semantic relationships among diseases. We then extracted D1 → D2 risk pairs from MEDLINE using the learned patterns. We manually evaluated the precisions of the learned patterns and extracted pairs. Finally, we analyzed the correlations between disease-disease risk pairs and their associated genes and drugs. The newly created dRiskKB consists of a total of 34,448 unique D1 → D2 pairs, representing the risk-specific semantic relationships among 12,981 diseases with each disease linked to its associated genes and drugs. The identified patterns are highly precise (average precision of 0.99) in specifying the risk-specific relationships among diseases. The precisions of extracted pairs are 0.919 for those that are exactly matched and 0.988 for those that are partially matched. By comparing the iterative pattern approach starting from different seeds, we demonstrated that our algorithm is robust in terms of seed choice. We show that diseases and their risk diseases as well as diseases with similar risk profiles tend to share both genes and drugs.

CONCLUSIONS

This unique dRiskKB, when combined with existing phenotypic, genetic, and genomic datasets, can have profound implications in our deeper understanding of disease etiology and in drug repositioning.

Probiotic treatments for induction and maintenance of remission in inflammatory bowel diseases: a meta-analysis of randomized controlled trials

Probiotics have been used for the treatment of inflammatory bowel diseases (IBD). However, the effects of probiotics on the induction and maintenance of remission in ulcerative colitis (UC) or Crohn's disease (CD) still remain controversial. This systematic review verified the findings of high-quality randomized controlled trials (RCTs) which investigated the therapeutic effects of probiotics on IBD. After the quality assessment, 20 RCTs which investigated the effects of probiotics on the induction or maintenance of remission in IBD were identified. From the results of the validation of these RCTs, beneficial effects of probiotic treatments to improve the response rate and remission rate on the remission induction therapies [risk ratio (RR) 1.81; 95 % confidence interval (CI) 1.40-2.35 and RR 1.56; 95 % CI 0.95-2.56, respectively] were verified. Furthermore, probiotic treatments exhibited effects equal to mesalazine on the maintenance of remission in UC (RR 1.00; 95 % CI 0.79-1.26). In contrast, no significant effect of probiotic treatments was shown in either the induction or maintenance of remission in CD. Because there were many variations in the conditions among these studies, a further analysis evaluating the effects of probiotic treatments in IBD is needed to clarify the optimal probiotics and treatment regimens for each condition or population in IBD patients.

Quality of reporting in systematic reviews of adverse events: systematic review

OBJECTIVES

To examine the quality of reporting of harms in systematic reviews, and to determine the need for a reporting guideline specific for reviews of harms.

DESIGN

Systematic review.

DATA SOURCES

Cochrane Database of Systematic Reviews (CDSR) and Database of Abstracts of Reviews of Effects (DARE).

REVIEW METHODS

Databases were searched for systematic reviews having an adverse event as the main outcome, published from January 2008 to April 2011. Adverse events included an adverse reaction, harms, or complications associated with any healthcare intervention. Articles with a primary aim to investigate the complete safety profile of an intervention were also included. We developed a list of 37 items to measure the quality of reporting on harms in each review; data were collected as dichotomous outcomes ("yes" or "no" for each item).

RESULTS

Of 4644 reviews identified, 309 were systematic reviews or meta-analyses primarily assessing harms (13 from CDSR; 296 from DARE). Despite a short time interval, the comparison between the years of 2008 and 2010-11 showed no difference on the quality of reporting over time (P=0.079). Titles in fewer than half the reviews (proportion of reviews 0.46 (95% confidence interval 0.40 to 0.52)) did not mention any harm related terms. Almost one third of DARE reviews (0.26 (0.22 to 0.31)) did not clearly define the adverse events reviewed, nor did they specify the study designs selected for inclusion in their methods section. Almost half of reviews (n=170) did not consider patient risk factors or length of follow-up when reviewing harms of an intervention. Of 67 reviews of complications related to surgery or other procedures, only four (0.05 (0.01 to 0.14)) reported professional qualifications of the individuals involved. The overall, unweighted, proportion of reviews with good reporting was 0.56 (0.55 to 0.57); corresponding proportions were 0.55 (0.53 to 0.57) in 2008, 0.55 (0.54 to 0.57) in 2009, and 0.57 (0.55 to 0.58) in 2010-11.

CONCLUSION

Systematic reviews compound the poor reporting of harms data in primary studies by failing to report on harms or doing so inadequately. Improving reporting of adverse events in systematic reviews is an important step towards a balanced assessment of an intervention.

Optimising the retrieval of information on adverse drug effects

Pharmaceutical interventions have brought about many benefits to health, improving the population's well-being and life expectancy. However, these interventions are not without potential harmful side-effects and yet searching for the evidence on adverse effects is challenging. This article summarises a PhD whose main aim was to develop a better understanding of the implications of using different sources and approaches to identifying relevant data on adverse effects. The author is Su Golder, who has recently completed her PhD at the University of York and who has already published several articles on specific aspects of her research, including this journal. This article is the first in the Dissertations into Practice series to report on a PhD study, and it summarises her research in a way which emphasises the implications for practice.

Reporting of harms data in RCTs: a systematic review of empirical assessments against the CONSORT harms extension

OBJECTIVE

To determine the standard of reporting of harms-related data, in randomised controlled trials (RCTs) according to the Consolidated Standards of Reporting Trials (CONSORT) statement extension for harms.

DESIGN

Systematic review.

DATA SOURCES

The Cochrane library, Ovid MEDLINE, Scopus and ISI Web of Knowledge were searched for relevant literature.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included publications of studies that used the CONSORT harms extension to assess the reporting of harms in RCTs.

RESULTS

We identified 7 studies which included between 10 and 205 RCTs. The clinical areas of the 7 studies were: hypertension (1), urology (1), epilepsy (1), complimentary medicine (2) and two not restricted to a clinical topic. Quality of the 7 studies was assessed by a risk of bias tool and was found to be variable. Adherence to the CONSORT harms criteria reported in the 7 studies was inadequate and variable across the items in the checklist. Adverse events are poorly defined, with 6 studies failing to exceed 50% adherence to the items in the checklist.

CONCLUSIONS

Readers of RCT publications need to be able to balance the trade-offs between benefits and harms of interventions. This systematic review suggests that this is compromised due to poor reporting of harms which is evident across a range of clinical areas. Improvements in quality could be achieved by wider adoption of the CONSORT harms criteria by journals reporting RCTs.

Adverse effects of iodine thyroid blocking: a systematic review

(131)I, when released in a radiological or nuclear accident as happened recently in Fukushima, Japan, may cause thyroid cancer as a long-term consequence. Iodine thyroid blocking (ITB) is known to reduce the risk of developing thyroid cancer. Potential adverse effects of ITB have not been systematically investigated so far. This article summarises the results of a review on adverse effects of ITB based on a systematic literature search in scientific medical databases. A meta-analysis was not performed as identified studies displayed major heterogeneity. The search resulted in 14 articles relevant to the topic, reporting mostly on surveys, ecological and intervention studies. Only one study from Poland focused on effects (both desired and adverse) of an ITB intervention following the Chernobyl accident. All other studies reported on iodine administration in a different context. Overall, the studies did not reveal severe adverse reactions to potassium iodide in the general public. Since ITB is a protective measure only applied in very specific circumstances, scientifically sound studies of adverse effects are scarce and consequently the evidence base is weak. The assessment of adverse effects of ITB relies on indirect evidence from related areas. This study may contribute to ongoing developments in pharmacoepidemiology aiming to better quantify adverse effects of medications and health care interventions including ITB.

The performance of adverse effects search filters in MEDLINE and EMBASE

BACKGROUND

 Search filters can potentially improve the efficiency of searches involving electronic databases such as medline and embase. Although search filters have been developed for identifying records that contain adverse effects data, little is known about the sensitivity of such filters.

OBJECTIVES

 This study measured the sensitivity of using available adverse effects filters to retrieve papers with adverse effects data.

METHODS

  A total of 233 included studies from 26 systematic reviews of adverse effects were used for analysis. Search filters from medline and embase were tested for their sensitivity in retrieving the records included in these reviews. In addition, the sensitivity of each individual search term used in at least one search filter was measured.

RESULTS

 Subheadings proved the most useful search terms in both medline and embase. No indexing terms in medline achieved over 12% sensitivity. The sensitivity of published search filters varied in medline from 3% to 93% and in embase from 57% to 97%. Whether this level of sensitivity is acceptable will be dependent on the purpose of the search.

CONCLUSIONS

 Although no adverse effects search filter captured all the relevant records, high sensitivity could be achieved. Search filters may therefore be useful in retrieving adverse effects data.

Discordance between conclusions stated in the abstract and conclusions in the article: analysis of published randomized controlled trials of systemic therapy in lung cancer

PURPOSE

Clinicians may read only the abstract of an article to keep abreast of newly published randomized controlled trials (RCTs). However, discordances have been noticed in summary conclusions in the abstracts and the main body of some articles. This article evaluated such discordances in detail.

METHODS

RCTs of systemic therapy for lung cancer published between 2004 and 2009 were considered. Conclusions in the body of the articles and those in the abstracts were graded by using a 7-point Likert scale; 1 for strong endorsement of the control arm, 4 for a neutral statement, and 7 for strong endorsement of the experimental arm. Conclusions were classified as discordant if the difference in scores was ≥ 2. χ(2) tests and logistic regression were used to identify factors associated with discordance.

RESULTS

From among 114 eligible RCTs identified (90 for non-small-cell and 24 for small-cell lung cancer), 11 (10%) articles presented discordant conclusions in the abstract and in the body of the articles. Discordance was most common when the experimental arm was strongly supported in the abstract but not in the body of the article (nine of 11; 82%); however, the converse was much less common (two of 11; 18%; P < .001). Intraclass correlations for the two reviewers were ≥ 0.9. The discordances were found to be independent of trial-related factors.

CONCLUSION

Conclusive statements in the abstract can differ from those in the full text. Clinicians should use caution when they consider making changes in their practice on the basis of reading only the abstract of a published RCT.

Systematic review of methods used in meta-analyses where a primary outcome is an adverse or unintended event

BACKGROUND

Adverse consequences of medical interventions are a source of concern, but clinical trials may lack power to detect elevated rates of such events, while observational studies have inherent limitations. Meta-analysis allows the combination of individual studies, which can increase power and provide stronger evidence relating to adverse events. However, meta-analysis of adverse events has associated methodological challenges. The aim of this study was to systematically identify and review the methodology used in meta-analyses where a primary outcome is an adverse or unintended event, following a therapeutic intervention.

METHODS

Using a collection of reviews identified previously, 166 references including a meta-analysis were selected for review. At least one of the primary outcomes in each review was an adverse or unintended event. The nature of the intervention, source of funding, number of individual meta-analyses performed, number of primary studies included in the review, and use of meta-analytic methods were all recorded. Specific areas of interest relating to the methods used included the choice of outcome metric, methods of dealing with sparse events, heterogeneity, publication bias and use of individual patient data.

RESULTS

The 166 included reviews were published between 1994 and 2006. Interventions included drugs and surgery among other interventions. Many of the references being reviewed included multiple meta-analyses with 44.6% (74/166) including more than ten. Randomised trials only were included in 42.2% of meta-analyses (70/166), observational studies only in 33.7% (56/166) and a mix of observational studies and trials in 15.7% (26/166). Sparse data, in the form of zero events in one or both arms where the outcome was a count of events, was found in 64 reviews of two-arm studies, of which 41 (64.1%) had zero events in both arms.

CONCLUSIONS

Meta-analyses of adverse events data are common and useful in terms of increasing the power to detect an association with an intervention, especially when the events are infrequent. However, with regard to existing meta-analyses, a wide variety of different methods have been employed, often with no evident rationale for using a particular approach. More specifically, the approach to dealing with zero events varies, and guidelines on this issue would be desirable.

Sensitivity and precision of adverse effects search filters in MEDLINE and EMBASE: a case study of fractures with thiazolidinediones

BACKGROUND

Search filters have been developed in MEDLINE and EMBASE to help overcome the challenges of searching electronic databases for information on adverse effects. However, little evaluation of their effectiveness has been carried out.

OBJECTIVES

To measure the sensitivity and precision of available adverse effects search filters in MEDLINE and EMBASE.

METHODS

A case study systematic review of fracture related adverse effects associated with the use of thiazolidinediones was used. Twelve MEDLINE search strategies and three EMBASE search strategies were tested.

RESULTS

Nineteen relevant references from MEDLINE and 24 from EMBASE were included in the review. Four search filters in MEDLINE achieved high sensitivity (95 or 100%) with an improved level of precision from searches without any adverse effects filter. High precision in MEDLINE could also be achieved (up to 53%) using search filters that rely on Medical Subject Headings. No search filter in EMBASE achieved high precision (all were under 5%) and the highest sensitivity in EMBASE was 83%.

CONCLUSIONS

Adverse effects search filters appear to be effective in MEDLINE for achieving either high sensitivity or high precision. Search filters in EMBASE, however, do not appear as effective, particularly in improving precision.

Complementary medicine and safety: a systematic investigation of design and reporting of systematic reviews

OBJECTIVES

The objective of this study was to examine the methods used in systematic reviews of safety across a range of complementary therapies to assess the variation in approach and the potential for developing guidance on conduct and reporting.

DESIGN

Systematic reviews focusing on safety were retrieved from NHS Evidence and searches of major databases. A pre-prepared template was used for data extraction. Information extracted included details of search strategies, sources, participants, interventions, reported adverse event/effect(s) and causality assessment. Data extraction was carried out by one researcher and a check for accuracy by a second researcher. Methods were assessed against criteria based on guidance provided by the Cochrane Adverse Effects Methods Group.

RESULTS

A total of 2563 citations were screened and 88 systematic reviews were selected for inclusion. The majority focused on the safety of herbs and nutritional supplements. Approximately half the reviews covered all aspects of safety; other reviews addressed specific adverse effects or interactions. Types of data included in the reviews did not always reflect the focus of the review. Search strategies, sources used, quality assessment and assessment of causality also varied.

CONCLUSIONS

Detailed examination and comparison of the methods has highlighted several areas in which there is potential for development of guidelines and consensus on standards. These include search strategies, sources of information, data extraction and assessment of causality. The value of systematic reviews in relation to large outcome studies requires further consideration.

Finding evidence for comparing medical interventions: AHRQ and the Effective Health Care Program

OBJECTIVE

This article discusses search methodology to identify evidence for comparative effectiveness reviews (CERs) as practiced by the Effective Health Care program.

STUDY DESIGN AND SETTING

Review.

RESULTS

Search methods described attempt to overcome the bias inherent in the publication and distribution of clinical evidence. Bibliographic databases and search strategies are discussed with special emphasis on searching for observational studies and harms data. Other techniques described include the use of key articles, citation tracking, hand searching, and personal communications. Strategies for locating gray literature, such as clinical trial protocols and regulatory information, are described. Search reporting and other practical matters are also discussed.

CONCLUSION

Better reporting and further research on search strategies is needed to develop additional evidence-based recommendations.

Dementia medications and risk of falls, syncope, and related adverse events: meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effect of cholinesterase inhibitors (ChEIs) and memantine on the risk of falls, syncope, and related events, defined as fracture and accidental injury.

DESIGN

Meta-analysis of randomized controlled trials that were identified from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (no language restriction, through July 2009), and manual search.

SETTING

Community and nursing homes.

PARTICIPANTS

Participants in fifty-four placebo-controlled randomized trials and extension studies of ChEIs and memantine that reported falls, syncope, and related events in cognitively impaired older adults.

MEASUREMENTS

Falls, syncope, fracture, and accidental injury.

RESULTS

ChEI use was associated with greater risk of syncope (odds ratio (OR)=1.53, 95% confidence interval (CI)=1.02-2.30) than placebo but not with other events (falls: OR=0.88, 95% CI=0.74-1.04; fracture: OR=1.39, 95% CI=0.75-2.56; accidental injury: OR=1.13, 95% CI=0.87-1.45). Memantine use was associated with fewer fractures (OR=0.21, 95% CI=0.05-0.85) but not with other events (falls: OR=0.92, 95% CI=0.72-1.18; syncope: OR=1.04, 95% CI=0.35-3.04; accidental injury: OR=0.80, 95% CI=0.56-1.12). There was no differential effect according to type and severity of cognitive impairment, residential status, or length of follow-up, although because of underreporting and small number of events, a potential benefit or risk cannot be excluded.

CONCLUSION

ChEIs may increase the risk of syncope, with no effects on falls, fracture, or accidental injury in cognitively impaired older adults. Memantine may have a favorable effect on fracture, with no effects on other events. More research is needed to confirm the reduction in fractures observed for memantine.

Dementia medications and risk of falls, syncope, and related adverse events: meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effect of cholinesterase inhibitors (ChEIs) and memantine on the risk of falls, syncope, and related events, defined as fracture and accidental injury.

DESIGN

Meta-analysis of randomized controlled trials that were identified from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (no language restriction, through July 2009), and manual search.

SETTING

Community and nursing homes.

PARTICIPANTS

Participants in fifty-four placebo-controlled randomized trials and extension studies of ChEIs and memantine that reported falls, syncope, and related events in cognitively impaired older adults.

MEASUREMENTS

Falls, syncope, fracture, and accidental injury.

RESULTS

ChEI use was associated with greater risk of syncope (odds ratio (OR)=1.53, 95% confidence interval (CI)=1.02-2.30) than placebo but not with other events (falls: OR=0.88, 95% CI=0.74-1.04; fracture: OR=1.39, 95% CI=0.75-2.56; accidental injury: OR=1.13, 95% CI=0.87-1.45). Memantine use was associated with fewer fractures (OR=0.21, 95% CI=0.05-0.85) but not with other events (falls: OR=0.92, 95% CI=0.72-1.18; syncope: OR=1.04, 95% CI=0.35-3.04; accidental injury: OR=0.80, 95% CI=0.56-1.12). There was no differential effect according to type and severity of cognitive impairment, residential status, or length of follow-up, although because of underreporting and small number of events, a potential benefit or risk cannot be excluded.

CONCLUSION

ChEIs may increase the risk of syncope, with no effects on falls, fracture, or accidental injury in cognitively impaired older adults. Memantine may have a favorable effect on fracture, with no effects on other events. More research is needed to confirm the reduction in fractures observed for memantine.

Not published, not indexed: issues in generating and finding hospice and palliative care literature

INTRODUCTION

Accessing new knowledge as the evidence base for hospice and palliative care grows has specific challenges for the discipline. This study aimed to describe conversion rates of palliative and hospice care conference abstracts to journal articles and to highlight that some palliative care literature may not be retrievable because it is not indexed on bibliographic databases.

METHODS

Substudy A tracked the journal publication of conference abstracts selected for inclusion in a gray literature database on www.caresearch.com.au . Abstracts were included in the gray literature database following handsearching of proceedings of over 100 Australian conferences likely to have some hospice or palliative care content that were held between 1980 and 1999. Substudy B looked at indexing from first publication until 2001 of three international hospice and palliative care journals in four widely available bibliographic databases through systematic tracing of all original papers in the journals.

RESULTS

Substudy A showed that for the 1338 abstracts identified only 15.9% were published (compared to an average in health of 45%). Published abstracts were found in 78 different journals. Multiauthor abstracts and oral presentations had higher rates of conversion. Substudy B demonstrated lag time between first publication and bibliographic indexing. Even after listing, idiosyncratic noninclusions were identified.

DISCUSSION

There are limitations to retrieval of all possible literature through electronic searching of bibliographic databases. Encouraging publication in indexed journals of studies presented at conferences, promoting selection of palliative care journals for database indexing, and searching more than one bibliographic database will improve the accessibility of existing and new knowledge in hospice and palliative care.

Is there an association between low dose aspirin and anemia (without overt bleeding)? Narrative review

Background

Overt bleeding associated with low dose aspirin (LDA) is well-recognized, little attention is given to the possibility of association between LDA and occult bleeding, although this is known to occur in healthy volunteers. LDA is used increasingly in primary and secondary prevention of a number of medical conditions, many of which are common in older people, as is anemia. Anemia in older people is associated with adverse outcomes including disability, morbidity and mortality. The purpose of this study was to review the evidence that LDA might cause anemia without overt bleeding.

Methods

An extensive narrative review was carried out. Electronic searching (including database links) and reference lists of reports were used to identify studies reporting on use of aspirin ≤325 mg/day and anemia or change in hemoglobin (Hb) without overt bleeding. Data were extracted from reports of trials, adverse drug reactions (ADRs) and prevalence studies of adults aged ≥18 years, published since 1980.

Results

There are few relevant data, with considerable heterogeneity among trial designs, duration, and patient characteristics in studies of LDA. In five randomised trials (n = 5879) in (mostly secondary) prevention, the majority of patients were men without peptic ulcer disease aged 50-70 years and no consistent association between LDA and change in Hb was found. In two smaller studies (n = 609) of primary prevention in healthy patients aged ≥70 years, there was a small but statistically significant fall in Hb with LDA. Observational studies, and data from trials in which use of LDA was not a primary focus of the study, were inconclusive.

Conclusions

It is not clear whether there is an association between LDA and anemia in the absence of overt bleeding, but there may be an association between LDA and fall in Hb in (a subset of) older patients. The available evidence has significant limitations, which are discussed; studies including more older patients, and publication of individual patient data, would help clarify this important matter.

Adverse effects of extra-articular corticosteroid injections: a systematic review

BACKGROUND

To estimate the occurrence and type of adverse effects after application of an extra-articular (soft tissue) corticosteroid injection.

METHODS

A systematic review of the literature was made based on a PubMed and Embase search covering the period 1956 to January 2010. Case reports were included, as were prospective and retrospective studies that reported adverse events of corticosteroid injection. All clinical trials which used extra-articular corticosteroid injections were examined. We divided the reported adverse events into major (defined as those needing intervention or not disappearing) and minor ones (transient, not requiring intervention).

RESULTS

The search yielded 87 relevant studies:44 case reports, 37 prospective studies and 6 retrospective studies. The major adverse events included osteomyelitis and protothecosis; one fatal necrotizing fasciitis; cellulitis and ecchymosis; tendon ruptures; atrophy of the plantar fat was described after injecting a neuroma; and local skin effects appeared as atrophy, hypopigmentation or as skin defect. The minor adverse events effects ranged from skin rash to flushing and disturbed menstrual pattern. Increased pain or steroid flare after injection was reported in 19 studies. After extra-articular injection, the incidence of major adverse events ranged from 0-5.8% and that of minor adverse events from 0-81%. It was not feasible to pool the risk for adverse effects due to heterogeneity of study populations and difference in interventions and variance in reporting.

CONCLUSION

In this literature review it was difficult to accurately quantify the incidence of adverse effects after extra-articular corticosteroid injection. The reported adverse events were relatively mild, although one fatal reaction was reported.

Meta-analysis of rare and adverse event data

Potentially beneficial drugs may have side effects. Such adverse events may be serious but rare, making their effect difficult to quantify, or even their identification problematic within randomized controlled trials. Meta-analysis provides a means of combining such outcome data across a series of studies and provides a more powerful analysis than is possible from a single study. However, meta-analysis of adverse event data presents some unique methodological challenges. Procedural issues pertaining to study selection and the inclusion of both randomized and observational data are discussed. The statistical problem of combining rare outcomes is also considered at length. Model choice, continuity corrections, exact statistics, Bayesian methods and sensitivity analysis are all covered. The application of results from adverse event meta-analyses to clinical and economic decision models is also considered. A number of examples are presented to illustrate the key points.

[CONSORT for reporting randomized controlled trials in journal and conference abstracts: explanation and elaboration]

BACKGROUND

Clear, transparent, and sufficiently detailed abstracts of conferences and journal articles related to randomized controlled trials (RCTs) are important, because readers often base their assessment of a trial solely on information in the abstract. Here, we extend the CONSORT (Consolidated Standards of Reporting Trials) Statement to develop a minimum list of essential items, which authors should consider when reporting the results of a RCT in any journal or conference abstract.

METHODS AND FINDINGS

We generated a list of items from existing quality assessment tools and empirical evidence. A three-round, modified-Delphi process was used to select items. In all, 109 participants were invited to participate in an electronic survey; the response rate was 61%. Survey results were presented at a meeting of the CONSORT Group in Montebello, Canada, January 2007, involving 26 participants, including clinical trialists, statisticians, epidemiologists, and biomedical editors. Checklist items were discussed for eligibility into the final checklist. The checklist was then revised to ensure that it reflected discussions held during and subsequent to the meeting. CONSORT for Abstracts recommends that abstracts relating to RCTs have a structured format. Items should include details of trial objectives; trial design (e.g., method of allocation, blinding/masking); trial participants (i.e., description, numbers randomized, and number analyzed); interventions intended for each randomized group and their impact on primary efficacy outcomes and harms; trial conclusions; trial registration name and number; and source of funding. We recommend the checklist be used in conjunction with this explanatory document, which includes examples of good reporting, rationale, and evidence, when available, for the inclusion of each item.

CONCLUSIONS

CONSORT for Abstracts aims to improve reporting of abstracts of RCTs published in journal articles and conference proceedings. It will help authors of abstracts of these trials provide the detail and clarity needed by readers wishing to assess a trial's validity and the applicability of its results.