Evidence synthesis for decision making 3: heterogeneity--subgroups, meta-regression, bias, and bias-adjustment

Renin angiotensin system inhibitors for patients with stable coronary artery disease without heart failure: systematic review and meta-analysis of randomized trials

OBJECTIVE

 To critically evaluate the efficacy of renin angiotensin system inhibitors (RASi) in patients with coronary artery disease without heart failure, compared with active controls or placebo.

DESIGN

 Meta-analysis of randomized trials.

DATA SOURCES

 PubMed, EMBASE, and CENTRAL databases until 1 May 2016.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

 Randomized trials of RASi versus placebo or active controls in patients with stable coronary artery disease without heart failure (defined as left ventricular ejection fraction ≥40% or without clinical heart failure). Each trial had to enroll at least 100 patients with coronary artery disease without heart failure, with at least one year's follow-up. Studies were excluded if they were redacted or compared use of angiotensin converting enzyme inhibitors with angiotensin receptor blockers. Outcomes were death, cardiovascular death, myocardial infarction, angina, stroke, heart failure, revascularization, incident diabetes, and drug withdrawal due to adverse effects.

RESULTS

 24 trials with 198 275 patient years of follow-up were included. RASi reduced the risk of all cause mortality (rate ratio 0.84, 95% confidence interval 0.72 to 0.98), cardiovascular mortality (0.74, 0.59 to 0.94), myocardial infarction (0.82, 0.76 to 0.88), stroke (0.79, 0.70 to 0.89), angina, heart failure, and revascularization when compared with placebo but not when compared with active controls (all cause mortality, 1.05, 0.94 to 1.17; P_interaction=0.006; cardiovascular mortality, 1.08, 0.93 to 1.25, P_interaction<0.001; myocardial infarction, 0.99, 0.87 to 1.12, P_interaction=0.01; stroke, 1.10, 0.93 to 1.31; P_interaction=0.002). Bayesian meta-regression analysis showed that the effect of RASi when compared with placebo on all cause mortality and cardiovascular mortality was dependent on the control event rate, such that RASi was only beneficial in trials with high control event rates (>14.10 deaths and >7.65 cardiovascular deaths per 1000 patient years) but not in those with low control event rates.

CONCLUSIONS

 In patients with stable coronary artery disease without heart failure, RASi reduced cardiovascular events and death only when compared with placebo but not when compared with active controls. Even among placebo controlled trials in this study, the benefit of RASi was mainly seen in trials with higher control event rates but not in those with lower control event rates. Evidence does not support a preferred status of RASi over other active controls.

Which is best for osteoporotic vertebral compression fractures: balloon kyphoplasty, percutaneous vertebroplasty or non-surgical treatment? A study protocol for a Bayesian network meta-analysis

INTRODUCTION

Osteoporotic vertebral compression fractures (OVCFs) commonly cause both acute and chronic back pain, substantial spinal deformity, functional disability and decreased quality of life and increase the risk of future vertebral fractures and mortality. Percutaneous vertebroplasty (PVP), balloon kyphoplasty (BK) and non-surgical treatment (NST) are mostly used for the treatment of OVCFs. However, which treatment is preferred is unknown. The purpose of this study is to comprehensively review the literature and ascertain the relative efficacy and safety of BK, PVP and NST for patients with OVCFs using a Bayesian network meta-analysis.

METHODS AND ANALYSIS

We will comprehensively search PubMed, EMBASE and the Cochrane Central Register of Controlled Trials, to include randomided controlled trials that compare BK, PVP or NST for treating OVCFs. The risk of bias for individual studies will be assessed according to the Cochrane Handbook. Bayesian network meta-analysis will be performed to compare the efficacy and safety of BK, PVP and NST. The quality of evidence will be evaluated by GRADE.

ETHICS AND DISSEMINATION

Ethical approval and patient consent are not required since this study is a meta-analysis based on published studies. The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication.

PROSPERO REGISTRATION NUMBER

CRD42016039452; Pre-results.

Additional considerations are required when preparing a protocol for a systematic review with multiple interventions

OBJECTIVES

The number of systematic reviews that aim to compare multiple interventions using network meta-analysis is increasing. In this study, we highlight aspects of a standard systematic review protocol that may need modification when multiple interventions are to be compared.

STUDY DESIGN AND SETTING

We take the protocol format suggested by Cochrane for a standard systematic review as our reference and compare the considerations for a pairwise review with those required for a valid comparison of multiple interventions. We suggest new sections for protocols of systematic reviews including network meta-analyses with a focus on how to evaluate their assumptions. We provide example text from published protocols to exemplify the considerations.

CONCLUSION

Standard systematic review protocols for pairwise meta-analyses need extensions to accommodate the increased complexity of network meta-analysis. Our suggested modifications are widely applicable to both Cochrane and non-Cochrane systematic reviews involving network meta-analyses.

An Overview of R in Health Decision Sciences

As the complexity of health decision science applications increases, high-level programming languages are increasingly adopted for statistical analyses and numerical computations. These programming languages facilitate sophisticated modeling, model documentation, and analysis reproducibility. Among the high-level programming languages, the statistical programming framework R is gaining increased recognition. R is freely available, cross-platform compatible, and open source. A large community of users who have generated an extensive collection of well-documented packages and functions supports it. These functions facilitate applications of health decision science methodology as well as the visualization and communication of results. Although R’s popularity is increasing among health decision scientists, methodological extensions of R in the field of decision analysis remain isolated. The purpose of this article is to provide an overview of existing R functionality that is applicable to the various stages of decision analysis, including model design, input parameter estimation, and analysis of model outputs.

Comparative effectiveness of different transarterial embolization therapies alone or in combination with local ablative or adjuvant systemic treatments for unresectable hepatocellular carcinoma: A network meta-analysis of randomized controlled trials

BACKGROUND

The optimal transcatheter embolization strategy for patients with unresectable hepatocellular carcinoma (HCC) remains elusive. We conducted a systematic review and network meta-analysis (NMA) of different embolization options for unresectable HCC.

METHODS

Medical databases were searched for randomized controlled trials evaluating bland transarterial embolization (TAE), conventional TACE, drug-eluting bead chemoembolization (DEB-TACE), or transarterial radioembolization (TARE), either alone or combined with adjuvant chemotherapy, or local liver ablation, or external radiotherapy for unresectable HCC up to June 2017. Random effects Bayesian models with a binomial and normal likelihood were fitted (WinBUGS). Primary endpoint was patient survival expressed as hazard ratios (HR) and 95% credible intervals. An exponential model was used to fit patient survival curves. Safety and objective response were calculated as odds ratios (OR) and accompanying 95% credible intervals. Competing treatments were ranked with the SUCRA statistic. Heterogeneity-adjusted effective sample sizes were calculated to evaluate information size for each comparison. Quality of evidence (QoE) was assessed with the GRADE system adapted for NMA reports. All analyses complied with the ISPOR-AMCP-NCP Task Force Report for good practice in NMA.

FINDINGS

The network of evidence included 55 RCTs (12 direct comparisons) with 5,763 patients with preserved liver function and unresectable HCC (intermediate to advanced stage). All embolization strategies achieved a significant survival gain over control treatment (HR range, 0.42-0.76; very low-to-moderate QoE). However, TACE, DEB-TACE, TARE and adjuvant systemic agents did not confer any survival benefit over bland TAE alone (moderate QoE, except low in case of TARE). There was moderate QoE that TACE combined with external radiation or liver ablation achieved the best patient survival (SUCRA 86% and 96%, respectively). Estimated median survival was 13.9 months in control, 18.1 months in TACE, 20.6 months with DEB-TACE, 20.8 months with bland TAE, 30.1 months in TACE plus external radiotherapy, and 33.3 months in TACE plus liver ablation. TARE was the safest treatment (SUCRA 77%), however, all examined therapies were associated with a significantly higher risk of toxicity over control (OR range, 6.35 to 68.5). TACE, DEB-TACE, TARE and adjuvant systemic agents did not improve objective response over bland embolization alone (OR range, 0.85 to 1.65). There was clinical diversity among included randomized controlled trials, but statistical heterogeneity was low.

CONCLUSIONS

Chemo- and radio-embolization for unresectable hepatocellular carcinoma may improve tumour objective response and patient survival, but are not more effective than bland particle embolization. Chemoembolization combined with external radiotherapy or local liver ablation may significantly improve tumour response and patient survival rates over embolization monotherapies. Quality of evidence remains mostly low to moderate because of clinical diversity.

SYSTEMATIC REVIEW REGISTRATION

CRD42016035796 (http://www.crd.york.ac.uk/PROSPERO).

Acupuncture for chronic pain and depression in primary care: a programme of research

Background

There has been an increase in the utilisation of acupuncture in recent years, yet the evidence base is insufficiently well established to be certain about its clinical effectiveness and cost-effectiveness. Addressing the questions related to the evidence base will reduce uncertainty and help policy- and decision-makers with regard to whether or not wider access is appropriate and provides value for money.

Aim

Our aim was to establish the most reliable evidence on the clinical effectiveness and cost-effectiveness of acupuncture for chronic pain by drawing on relevant evidence, including recent high-quality trials, and to develop fresh evidence on acupuncture for depression. To extend the evidence base we synthesised the results of published trials using robust systematic review methodology and conducted a randomised controlled trial (RCT) of acupuncture for depression.

Methods and results

We synthesised the evidence from high-quality trials of acupuncture for chronic pain, consisting of musculoskeletal pain related to the neck and low back, osteoarthritis of the knee, and headache and migraine, involving nearly 18,000 patients. In an individual patient data (IPD) pairwise meta-analysis, acupuncture was significantly better than both sham acupuncture (p < 0.001) and usual care (p < 0.001) for all conditions. Using network meta-analyses, we compared acupuncture with other physical therapies for osteoarthritis of the knee. In both an analysis of all available evidence and an analysis of a subset of better-quality trials, using aggregate-level data, we found acupuncture to be one of the more effective therapies. We developed new Bayesian methods for analysing multiple individual patient-level data sets to evaluate heterogeneous continuous outcomes. An accompanying cost-effectiveness analysis found transcutaneous electrical nerve stimulation (TENS) to be cost-effective for osteoarthritis at a threshold of £20,000 per quality-adjusted life-year when all trials were synthesised. When the analysis was restricted to trials of higher quality with adequate allocation concealment, acupuncture was cost-effective. In a RCT of acupuncture or counselling compared with usual care for depression, in which half the patients were also experiencing comorbid pain, we found acupuncture and counselling to be clinically effective and acupuncture to be cost-effective. For patients in whom acupuncture is inappropriate or unavailable, counselling is cost-effective.

Conclusion

We have provided the most robust evidence from high-quality trials on acupuncture for chronic pain. The synthesis of high-quality IPD found that acupuncture was more effective than both usual care and sham acupuncture. Acupuncture is one of the more clinically effective physical therapies for osteoarthritis and is also cost-effective if only high-quality trials are analysed. When all trials are analysed, TENS is cost-effective. Promising clinical and economic evidence on acupuncture for depression needs to be extended to other contexts and settings. For the conditions we have investigated, the drawing together of evidence on acupuncture from this programme of research has substantially reduced levels of uncertainty. We have identified directions for further research. Our research also provides a valuable basis for considering the potential role of acupuncture as a referral option in health care and enabling providers and policy-makers to make decisions based on robust sources of evidence.

Trial registration

Current Controlled Trials ISRCTN63787732.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Automated drawing of network plots in network meta-analysis

In systematic reviews based on network meta-analysis, the network structure should be visualized. Network plots often have been drawn by hand using generic graphical software. A typical way of drawing networks, also implemented in statistical software for network meta-analysis, is a circular representation, often with many crossing lines. We use methods from graph theory in order to generate network plots in an automated way. We give a number of requirements for graph drawing and present an algorithm that fits prespecified ideal distances between the nodes representing the treatments. The method was implemented in the function netgraph of the R package netmeta and applied to a number of networks from the literature. We show that graph representations with a small number of crossing lines are often preferable to circular representations.

IMPRoving Outcomes for children exposed to domestic ViolencE (IMPROVE): an evidence synthesis

Background

Exposure to domestic violence and abuse (DVA) during childhood and adolescence increases the risk of negative outcomes across the lifespan.

Objectives

To synthesise evidence on the clinical effectiveness, cost-effectiveness and acceptability of interventions for children exposed to DVA, with the aim of making recommendations for further research.

Design

(1) A systematic review of controlled trials of interventions; (2) a systematic review of qualitative studies of participant and professional experience of interventions; (3) a network meta-analysis (NMA) of controlled trials and cost-effectiveness analysis; (4) an overview of current UK provision of interventions; and (5) consultations with young people, parents, service providers and commissioners.

Settings

North America (11), the Netherlands (1) and Israel (1) for the systematic review of controlled trials of interventions; the USA (4) and the UK (1) for the systematic review of qualitative studies of participant and professional experience of interventions; and the UK for the overview of current UK provision of interventions and consultations with young people, parents, service providers and commissioners.

Participants

A total of 1345 children for the systematic review of controlled trials of interventions; 100 children, 202 parents and 39 professionals for the systematic review of qualitative studies of participant and professional experience of interventions; and 16 young people, six parents and 20 service providers and commissioners for the consultation with young people, parents, service providers and commissioners.

Interventions

Psychotherapeutic, advocacy, parenting skills and advocacy, psychoeducation, psychoeducation and advocacy, guided self-help.

Main outcome measures

Internalising symptoms and externalising behaviour, mood, depression symptoms and diagnosis, post-traumatic stress disorder symptoms and self-esteem for the systematic review of controlled trials of interventions and NMA; views about and experience of interventions for the systematic review of qualitative studies of participant and professional experience of interventions and consultations.

Data sources

MEDLINE, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, EMBASE, Cochrane Central Register of Controlled Trials, Science Citation Index, Applied Social Sciences Index and Abstracts, International Bibliography of the Social Sciences, Social Services Abstracts, Social Care Online, Sociological Abstracts, Social Science Citation Index, World Health Organization trials portal and clinicaltrials.gov.

Review methods

A narrative review; a NMA and incremental cost-effectiveness analysis; and a qualitative synthesis.

Results

The evidence base on targeted interventions was small, with limited settings and types of interventions; children were mostly < 14 years of age, and there was an absence of comparative studies. The interventions evaluated in trials were mostly psychotherapeutic and psychoeducational interventions delivered to the non-abusive parent and child, usually based on the child’s exposure to DVA (not specific clinical or broader social needs). Qualitative studies largely focused on psychoeducational interventions, some of which included the abusive parent. The evidence for clinical effectiveness was as follows: 11 trials reported improvements in behavioural or mental health outcomes, with modest effect sizes but significant heterogeneity and high or unclear risk of bias. Psychoeducational group-based interventions delivered to the child were found to be more effective for improving mental health outcomes than other types of intervention. Interventions delivered to (non-abusive) parents and to children were most likely to be effective for improving behavioural outcomes. However, there is a large degree of uncertainty around comparisons, particularly with regard to mental health outcomes. In terms of evidence of cost-effectiveness, there were no economic studies of interventions. Cost-effectiveness was modelled on the basis of the NMA, estimating differences between types of interventions. The outcomes measured in trials were largely confined to children’s mental health and behavioural symptoms and disorders, although stakeholders’ concepts of success were broader, suggesting that a broader range of outcomes should be measured in trials. Group-based psychoeducational interventions delivered to children and non-abusive parents in parallel were largely acceptable to all stakeholders. There is limited evidence for the acceptability of other types of intervention. In terms of the UK evidence base and service delivery landscape, there were no UK-based trials, few qualitative studies and little widespread service evaluation. Most programmes are group-based psychoeducational interventions. However, the funding crisis in the DVA sector is significantly undermining programme delivery.

Conclusions

The evidence base regarding the acceptability, clinical effectiveness and cost-effectiveness of interventions to improve outcomes for children exposed to DVA is underdeveloped. There is an urgent need for more high-quality studies, particularly trials, that are designed to produce actionable, generalisable findings that can be implemented in real-world settings and that can inform decisions about which interventions to commission and scale. We suggest that there is a need to pause the development of new interventions and to focus on the systematic evaluation of existing programmes. With regard to the UK, we have identified three types of programme that could be justifiably prioritised for further study: psycho-education delivered to mothers and children, or children alone; parent skills training in combination with advocacy: and interventions involving the abusive parent/caregiver. We also suggest that there is need for key stakeholders to come together to explicitly identify and address the structural, practical and cultural barriers that may have hampered the development of the UK evidence base to date.

Future work recommendations

There is a need for well-designed, well-conducted and well-reported UK-based randomised controlled trials with cost-effectiveness analyses and nested qualitative studies. Development of consensus in the field about core outcome data sets is required. There is a need for further exploration of the acceptability and effectiveness of interventions for specific groups of children and young people (i.e. based on ethnicity, age, trauma exposure and clinical profile). There is also a need for an investigation of the context in which interventions are delivered, including organisational setting and the broader community context, and the evaluation of qualities, qualifications and disciplines of personnel delivering interventions. We recommend prioritisation of psychoeducational interventions and parent skills training delivered in combination with advocacy in the next phase of trials, and exploratory trials of interventions that engage both the abusive and the non-abusive parent.

Study registration

This study is registered as PROSPERO CRD42013004348 and PROSPERO CRD420130043489.

Funding

The National Institute for Health Research Public Health Research programme.

Comparative Effectiveness of Plain Balloon Angioplasty, Bare Metal Stents, Drug-Coated Balloons, and Drug-Eluting Stents for the Treatment of Infrapopliteal Artery Disease: Systematic Review and Bayesian Network Meta-analysis of Randomized Controlled Trials

PURPOSE

To report a Bayesian network meta-analysis of randomized controlled trials (RCTs) comparing bare metal stents (BMS), paclitaxel-coated balloons (PCBs), and drug-eluting stents (DES) with balloon angioplasty (BA) or with each other in the infrapopliteal arteries.

METHODS

Sixteen RCTs comprising 1805 patients with 1-year median follow-up were analyzed. Bayesian random effects binomial models were employed (WinBUGS). Relative treatment effects were expressed as odds ratios (ORs) with 95% credible intervals (CrI), and the cumulative rank probabilities were calculated to provide hierarchies of competing treatments. Quality of evidence (QoE) was assessed with the GRADE (grading of recommendations assessment, development, and evaluation) system. Sensitivity, heterogeneity, and consistency analyses were performed.

RESULTS

There was high QoE that infrapopliteal DES significantly reduced restenosis compared with BMS (OR 0.26, 95% CrI 0.12 to 0.51) and BA (OR 0.22, 95% CrI 0.11 to 0.45). Likewise, DES significantly reduced target lesion revascularization (TLR) compared with BA (OR 0.41, 95% CrI 0.22 to 0.75) and BMS (OR 0.26, 95% CrI 0.15 to 0.45). Paclitaxel-coated balloons also reduced TLR compared with BA (OR 0.55, 95% CrI 0.34 to 0.90) and BMS (OR 0.35, 95% CrI 0.18 to 0.67), but QoE was low to moderate. BA had lower TLR than BMS (OR 0.63, 95% CrI 0.40 to 0.99) with high QoE. DES was the only treatment that significantly reduced limb amputations compared with BA (OR 0.58, 95% CrI 0.35 to 0.96), PCB (OR 0.51, 95% CrI 0.26 to 0.98), or BMS (OR 0.38, 95% CrI 0.19 to 0.72) with moderate to high QoE. DES also significantly improved wound healing compared with BA (OR 2.02, 95% CrI 1.01 to 4.07) or BMS (OR 3.45, 95% CrI 1.41 to 8.73) with high QoE. Results were stable on sensitivity and meta-regression analyses without any significant publication bias or inconsistency.

CONCLUSION

Infrapopliteal DES were associated with significantly lower rates of restenosis, TLR, and amputations and improved wound healing compared to BA and BMS. DES also significantly reduced amputations compared with PCB.

Interventions to improve adherence to antiretroviral therapy: a systematic review and network meta-analysis

BACKGROUND

High adherence to antiretroviral therapy is crucial to the success of HIV treatment. We evaluated comparative effectiveness of adherence interventions with the aim of informing the WHO's global guidance on interventions to increase adherence.

METHODS

For this systematic review and network meta-analysis, we searched for randomised controlled trials of interventions that aimed to improve adherence to antiretroviral therapy regimens in populations with HIV. We searched Cochrane Central Register of Controlled Trials, Embase, and MEDLINE for reports published up to July 16, 2015, and searched major conference abstracts from Jan 1, 2013, to July 16, 2015. We extracted data from eligible studies for study characteristics, interventions, patients' characteristics at baseline, and outcomes for the study populations of interest. We used network meta-analyses to compare adherence and viral suppression for all study settings (global network) and for studies in low-income and middle-income countries only (LMIC network).

FINDINGS

We obtained data from 85 trials with 16 271 participants. Short message service (SMS; text message) interventions were superior to standard of care in improving adherence in both the global network (odds ratio [OR] 1·48, 95% credible interval [CrI] 1·00-2·16) and in the LMIC network (1·49, 1·04-2·09). Multiple interventions showed generally superior adherence to single interventions, indicating additive effects. For viral suppression, only cognitive behavioural therapy (1·46, 1·05-2·12) and supporter interventions (1·28, 1·01-1·71) were superior to standard of care in the global network; none of the interventions improved viral response in the LMIC network. For the global network, the time discrepancy (whether the study outcome was measured during or after intervention was withdrawn) was an effect modifier for both adherence to antiretroviral therapy (coefficient estimate -0·43, 95% CrI -0·75 to -0·11) and viral suppression (-0·48; -0·84 to -0·12), suggesting that the effects of interventions wane over time.

INTERPRETATION

Several interventions can improve adherence and viral suppression; generally, their estimated effects were modest and waned over time.

FUNDING

WHO.

Tumour necrosis factor-α inhibitors for ankylosing spondylitis and non-radiographic axial spondyloarthritis: a systematic review and economic evaluation

BACKGROUND

Tumour necrosis factor (TNF)-α inhibitors (anti-TNFs) are typically used when the inflammatory rheumatologic diseases ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-AxSpA) have not responded adequately to conventional therapy. Current National Institute for Health and Care Excellence (NICE) guidance recommends treatment with adalimumab, etanercept and golimumab in adults with active (severe) AS only if certain criteria are fulfilled but it does not recommend infliximab for AS. Anti-TNFs for patients with nr-AxSpA have not previously been appraised by NICE.

OBJECTIVE

To determine the clinical effectiveness, safety and cost-effectiveness within the NHS of adalimumab, certolizumab pegol, etanercept, golimumab and infliximab, within their licensed indications, for the treatment of severe active AS or severe nr-AxSpA (but with objective signs of inflammation).

DESIGN

Systematic review and economic model.

DATA SOURCES

Fifteen databases were searched for relevant studies in July 2014.

REVIEW METHODS

Clinical effectiveness data from randomised controlled trials (RCTs) were synthesised using Bayesian network meta-analysis methods. Results from other studies were summarised narratively. Only full economic evaluations that compared two or more options and considered both costs and consequences were included in the systematic review of cost-effectiveness studies. The differences in the approaches and assumptions used across the studies, and also those in the manufacturer's submissions, were examined in order to explain any discrepancies in the findings and to identify key areas of uncertainty. A de novo decision model was developed with a generalised framework for evidence synthesis that pooled change in disease activity (BASDAI and BASDAI 50) and simultaneously synthesised information on function (BASFI) to determine the long-term quality-adjusted life-year and cost burden of the disease in the economic model. The decision model was developed in accordance with the NICE reference case. The model has a lifetime horizon (60 years) and considers costs from the perspective of the NHS and personal social services. Health effects were expressed in terms of quality-adjusted life-years.

RESULTS

In total, 28 eligible RCTs were identified and 26 were placebo controlled (mostly up to 12 weeks); 17 extended into open-label active treatment-only phases. Most RCTs were judged to have a low risk of bias overall. In both AS and nr-AxSpA populations, anti-TNFs produced clinically important benefits to patients in terms of improving function and reducing disease activity; for AS, the relative risks for ASAS 40 ranged from 2.53 to 3.42. The efficacy estimates were consistently slightly smaller for nr-AxSpA than for AS. Statistical (and clinical) heterogeneity was more apparent in the nr-AxSpA analyses than in the AS analyses; both the reliability of the nr-AxSpA meta-analysis results and their true relevance to patients seen in clinical practice are questionable. In AS, anti-TNFs are approximately equally effective. Effectiveness appears to be maintained over time, with around 50% of patients still responding at 2 years. Evidence for an effect of anti-TNFs delaying disease progression was limited; results from ongoing long-term studies should help to clarify this issue. Sequential treatment with anti-TNFs can be worthwhile but the drug survival response rates and benefits are reduced with second and third anti-TNFs. The de novo model, which addressed many of the issues of earlier evaluations, generated incremental cost-effectiveness ratios ranging from £19,240 to £66,529 depending on anti-TNF and modelling assumptions.

CONCLUSIONS

In both AS and nr-AxSpA populations anti-TNFs are clinically effective, although more so in AS than in nr-AxSpA. Anti-TNFs may be an effective use of NHS resources depending on which assumptions are considered appropriate.

FUTURE WORK RECOMMENDATIONS

Randomised trials are needed to identify the nr-AxSpA population who will benefit the most from anti-TNFs.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014010182.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Methods to decrease blood loss during liver resection: a network meta-analysis

BACKGROUND

Liver resection is a major surgery with significant mortality and morbidity. Specialists have tested various methods in attempts to limit blood loss, transfusion requirements, and morbidity during elective liver resection. These methods include different approaches (anterior versus conventional approach), use of autologous blood donation, cardiopulmonary interventions such as hypoventilation, low central venous pressure, different methods of parenchymal transection, different methods of management of the raw surface of the liver, different methods of vascular occlusion, and different pharmacological interventions. A surgeon typically uses only one of the methods from each of these seven categories. The optimal method to decrease blood loss and transfusion requirements in people undergoing liver resection is unknown.

OBJECTIVES

To assess the effects of different interventions for decreasing blood loss and blood transfusion requirements during elective liver resection.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and Science Citation Index Expanded to September 2015 to identify randomised clinical trials. We also searched trial registers and handsearched the references lists of identified trials.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) comparing different methods of decreasing blood loss and blood transfusion requirements in people undergoing liver resection.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials and collected data. We assessed the risk of bias using Cochrane domains. We conducted a Bayesian network meta-analysis using the Markov chain Monte Carlo method in WinBUGS 1.4, following the guidelines of the National Institute for Health and Care Excellence Decision Support Unit guidance documents. We calculated the odds ratios (OR) with 95% credible intervals (CrI) for the binary outcomes, mean differences (MD) with 95% CrI for continuous outcomes, and rate ratios with 95% CrI for count outcomes, using a fixed-effect model or random-effects model according to model-fit. We assessed the evidence with GRADE.

MAIN RESULTS

We identified 67 randomised clinical trials involving a total of 6197 participants. All the trials were at high risk of bias. A total of 5771 participants from 64 trials provided data for one or more outcomes included in this review. There was no evidence of differences in most of the comparisons, and where there was, these differences were in single trials, mostly of small sample size. We summarise only the evidence that was available in more than one trial below. Of the primary outcomes, the only one with evidence of a difference from more than one trial under the pair-wise comparison was in the number of adverse events (complications), which was higher with radiofrequency dissecting sealer than with the clamp-crush method (rate ratio 1.85, 95% CrI 1.07 to 3.26; 250 participants; 3 studies; very low-quality evidence). Among the secondary outcomes, the only differences we found from more than one trial under the pair-wise comparison were the following: blood transfusion (proportion) was higher in the low central venous pressure group than in the acute normovolemic haemodilution plus low central venous pressure group (OR 3.19, 95% CrI 1.56 to 6.95; 208 participants; 2 studies; low-quality evidence); blood transfusion quantity (red blood cells) was lower in the fibrin sealant group than in the control (MD -0.53 units, 95% CrI -1.00 to -0.07; 122 participants; 2; very low-quality evidence); blood transfusion quantity (fresh frozen plasma) was higher in the oxidised cellulose group than in the fibrin sealant group (MD 0.53 units, 95% CrI 0.36 to 0.71; 80 participants; 2 studies; very low-quality evidence); blood loss (MD -0.34 L, 95% CrI -0.46 to -0.22; 237 participants; 4 studies; very low-quality evidence), total hospital stay (MD -2.42 days, 95% CrI -3.91 to -0.94; 197 participants; 3 studies; very low-quality evidence), and operating time (MD -15.32 minutes, 95% CrI -29.03 to -1.69; 192 participants; 4 studies; very low-quality evidence) were lower with low central venous pressure than with control. For the other comparisons, the evidence for difference was either based on single small trials or there was no evidence of differences. None of the trials reported health-related quality of life or time needed to return to work.

AUTHORS' CONCLUSIONS

Paucity of data meant that we could not assess transitivity assumptions and inconsistency for most analyses. When direct and indirect comparisons were available, network meta-analysis provided additional effect estimates for comparisons where there were no direct comparisons. However, the paucity of data decreases the confidence in the results of the network meta-analysis. Low-quality evidence suggests that liver resection using a radiofrequency dissecting sealer may be associated with more adverse events than with the clamp-crush method. Low-quality evidence also suggests that the proportion of people requiring a blood transfusion is higher with low central venous pressure than with acute normovolemic haemodilution plus low central venous pressure; very low-quality evidence suggests that blood transfusion quantity (red blood cells) was lower with fibrin sealant than control; blood transfusion quantity (fresh frozen plasma) was higher with oxidised cellulose than with fibrin sealant; and blood loss, total hospital stay, and operating time were lower with low central venous pressure than with control. There is no evidence to suggest that using special equipment for liver resection is of any benefit in decreasing the mortality, morbidity, or blood transfusion requirements (very low-quality evidence). Radiofrequency dissecting sealer should not be used outside the clinical trial setting since there is low-quality evidence for increased harm without any evidence of benefits. In addition, it should be noted that the sample size was small and the credible intervals were wide, and we cannot rule out considerable benefit or harm with a specific method of liver resection.

Comparison of sedation strategies for critically ill patients: a protocol for a systematic review incorporating network meta-analyses

BACKGROUND

Sedatives and analgesics are administered to provide sedation and manage agitation and pain in most critically ill mechanically ventilated patients. Various sedation administration strategies including protocolized sedation and daily sedation interruption are used to mitigate drug pharmacokinetic limitations and minimize oversedation, thereby shortening the duration of mechanical ventilation. At present, it is unclear which strategy is most effective, as few have been directly compared. Our review will use network meta-analysis (NMA) to compare and rank sedation strategies to determine their efficacy and safety for mechanically ventilated patients.

METHODS

We will search the following from 1980 to March 2016: Ovid MEDLINE, CINAHL, Embase, PsycINFO, and Web of Science. We will also search the Cochrane Library, gray literature, and the International Clinical Trials Registry Platform. We will use a validated randomized control trial search filter to identify studies evaluating any strategy to optimize sedation in mechanically ventilated adult patients. Authors will independently extract data from eligible studies in duplicate and complete the Cochrane Risk of Bias tool. Our outcomes of interest include duration of mechanical ventilation, time to first extubation, ICU and hospital length of stay, re-intubation, tracheostomy, mortality, total sedative and opioid exposure, health-related quality of life, and adverse events. To inform our NMA, we will first conduct conventional pair-wise meta-analyses using random-effects models. Where appropriate, we will perform Bayesian NMA using WinBUGS software.

DISCUSSION

There are multiple strategies to optimize sedation for mechanically ventilated patients. Current ICU guidelines recommend protocolized sedation or daily sedation interruption. Our systematic review incorporating NMA will provide a unified analysis of all sedation strategies to determine the relative efficacy and safety of interventions that may not have been compared directly. We will provide knowledge users, decision makers, and professional societies with ranking of multiple sedation strategies to inform future sedation guidelines.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016037480.

Effect of a national requirement to introduce named accountable general practitioners for patients aged 75 or older in England: regression discontinuity analysis of general practice utilisation and continuity of care

OBJECTIVE

To assess the effect of introducing named accountable general practitioners (GPs) for patients aged 75 years on patterns of general practice utilisation, including continuity of care.

DESIGN

Regression discontinuity design applied to data from the Clinical Practice Research Datalink to estimate the treatment effect for compliers aged 75.

SETTING

200 general practices in England.

PARTICIPANTS

255 469 patients aged between 65 and 85, after excluding those aged 75.

INTERVENTION

From April 2014, general practices in England were required to offer patients aged 75 or over a named accountable GP. This study compared having named accountable GPs for patients aged just over 75 with usual care provided for patients just under 75.

OUTCOMES

Number of contacts (face-to-face or telephone) with GPs, longitudinal continuity of care (usual provider of care, or UPC, index), number of referrals to specialist care and numbers of common diagnostic tests. Outcomes were measured over 9 months following assignment to a named accountable GP and for a comparable period for those unassigned.

RESULTS

The proportion of patients with a named accountable GP increased from 3.5% to 79.8% at age 75. No statistically significant effects were detected for continuity of care (estimated treatment effect 0.00, 95% CI -0.01 to 0.02) or the number of GP contacts per person (estimated treatment effect -0.11, 95% CI -0.31 to 0.09) over 9 months. No significant change was seen in the number of referrals, blood pressure or HbA1c diagnostic tests per person. A statistically significant treatment effect of -0.05 cholesterol tests per person (95% CI -0.07 to -0.02) was estimated; however, sensitivity analysis indicated that this effect predated the introduction of named accountable GPs.

CONCLUSIONS

Continuity of care is valued by patients, but the named accountable GP initiative did not improve continuity of care or change patterns of GP utilisation in the first 9 months of the policy.

Risk of serious infections with immunosuppressive drugs and glucocorticoids for lupus nephritis: a systematic review and network meta-analysis

BACKGROUND

To perform a systematic review and network meta-analysis (NMA) to compare the risk of serious infections with immunosuppressive medications and glucocorticoids in lupus nephritis.

METHODS

A trained librarian performed two searches: (1) PubMed for all lupus nephritis trials from the end dates for the systematic review for the 2012 American College of Rheumatology (ACR) lupus nephritis treatment guidelines and the 2012 Cochrane Systematic Review on treatments for lupus nephritis, to September 2013; and (2) PubMed and SCOPUS for all lupus trials (excluding lupus nephritis) from inception to February 2014, to obtain additional trials for harms data in any lupus patient. The search was updated to May 2016. Duplicate title/abstract review and duplicate data abstractions by two abstractors independently was performed for all eligible studies, including those studies abstracted for the 2012 ACR lupus nephritis treatment guidelines and the 2012 Cochrane Systematic Review on lupus nephritis treatments. We performed a systematic review and a Bayesian NMA, including randomized controlled trials (RCTs) of immunosuppressive drugs or glucocorticoids in patients with lupus nephritis assessing serious infection risk. Markov chain Monte Carlo methods were used to model 95 % credible intervals (CrI). Sensitivity analyses examined the robustness of estimates.

RESULTS

A total of 32 RCTs with 2611 patients provided data. There were 26 two-arm, five three-arm, and one four-arm trials. We found that tacrolimus was associated with significantly lower risk of serious infections compared to glucocorticoids, cyclophosphamide (CYC), mycophenolate mofetil (MMF), and azathioprine (AZA) with odds ratios (95 % CrI) of 0.33 (0.12-0.88), 0.37 (0.15-0.87), 0.340 (0.18-0.81), and 0.32 (0.12-0.81), respectively. Conversely, CYC low dose (LD), CYC high dose (HD), and HD glucocorticoids were associated with higher odds of serious infections compared to tacrolimus, ranging from 4.84 to 12.83. We also found that MMF followed by AZA (MMF-AZA) was associated with significantly lower risk of serious infections as compared to CYC LD, CYC HD, CYC-AZA, or HD glucocorticoids with odds ratios (95 % CrI) of 0.09 (0.01-0.76), 0.07 (0.01-0.54), 0.14 (0.02-0.71), and 0.03 (0.00-0.56), respectively. Estimates were similar to pair-wise meta-analyses. Sensitivity analyses that varied estimate (odds ratio vs. Peto's odds ratio), method (random vs. fixed effects model), data (sepsis vs. serious infection data; exclusion of observational studies), treatment grouping (CYC and CYC HD as a combined treatment group vs. separate), made little/no difference to these estimates.

CONCLUSIONS

Tacrolimus and MMF-AZA combination were associated with lower risk of serious infections compared to other immunosuppressive drugs or glucocorticoids for lupus nephritis. In conjunction with comparative efficacy data, these data can help patients make informed decisions about treatment options for lupus nephritis.

PROSPERO REGISTRATION

CRD42016032965.

Comparison of pharmacological and non-pharmacological interventions to prevent delirium in critically ill patients: a protocol for a systematic review incorporating network meta-analyses

BACKGROUND

Delirium is characterized by acute changes in mental status including inattention, disorganized thinking, and altered level of consciousness, and is highly prevalent in critically ill adults. Delirium has adverse consequences for both patients and the healthcare system; however, at this time, no effective treatment exists. The identification of effective prevention strategies is therefore a clinical and research imperative. An important limitation of previous reviews of delirium prevention is that interventions were considered in isolation and only direct evidence was used. Our systematic review will synthesize all existing data using network meta-analysis, a powerful statistical approach that enables synthesis of both direct and indirect evidence.

METHODS

We will search Ovid MEDLINE, CINAHL, Embase, PsycINFO, and Web of Science from 1980 to March 2016. We will search the PROSPERO registry for protocols and the Cochrane Library for published systematic reviews. We will examine reference lists of pertinent reviews and search grey literature and the International Clinical Trials Registry Platform for unpublished studies and ongoing trials. We will include randomized and quasi-randomized trials of critically ill adults evaluating any pharmacological, non-pharmacological, or multi-component intervention for delirium prevention, administered in or prior to (i.e., peri-operatively) transfer to the ICU. Two authors will independently screen search results and extract data from eligible studies. Risk of bias assessments will be completed on all included studies. To inform our network meta-analysis, we will first conduct conventional pair-wise meta-analyses for primary and secondary outcomes using random-effects models. We will generate our network meta-analysis using a Bayesian framework, assuming a common heterogeneity parameter across all comparisons, and accounting for correlations in multi-arm studies. We will perform analyses using WinBUGS software.

DISCUSSION

This systematic review will address the existing knowledge gap regarding best practices for delirium prevention in critically ill adults by synthesizing evidence from trials of pharmacological, non-pharmacological, and multi-component interventions administered in or prior to transfer to the ICU. Use of network meta-analysis will clarify which delirium prevention strategies are most effective in improving clinical outcomes while causing least harm. The network meta-analysis is a novel approach and will provide knowledge users and decision makers with comparisons of multiple interventions of delirium prevention strategies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016036313.

Antibiotics for eradicating meningococcal carriages: Network meta-analysis and investigation of evidence inconsistency

AIM

To compare different antibiotics for eradicating the carriage of Neisseria meningitidis (N. meningitidis), and to investigate heterogeneity and evidence inconsistency.

METHODS

From a search of PubMed and published systematic reviews, we identified 23 trials evaluating 15 antibiotics that could be connected in a trial network. The outcome of interest is the eradication of N. meningitidis. We used WinBUGS to conduct random-effects, mixed treatment comparisons. Heterogeneity and evidence inconsistency was investigated by meta-regression modelling and examining characteristics of trial participants and interventions evaluated.

RESULTS

Rifampin, ciprofloxacin, minocycline, ceftriaxone, and azythromycin were statistically significantly (P < 0.05) more effective than placebo. The probability of being the best was 67.0% for a combination of rifampin and minocycline, 25.0% for ceftriaxone, 1.7% for azythromycin, and below 1% for the remaining regimens. Significant inconsistency between the direct and indirect estimates was observed for the comparison of rifampin and ciprofloxacin (P < 0.01), which may be caused by different types of carriers and different doses of ciprofloxacin.

CONCLUSION

A range of prophylactic antibiotic regimens are effective for eradicating meningococcal carriages, and treatment choice will depend on the individual priorities of the patients and physicians. In clinical situations where complete eradication is considered to be of the utmost importance, a combination of rifampin and minocycline seems to offer the highest likelihood of success. Ceftriaxone as a single intramuscular injection is also likely to be more effective as compared with the other two antibiotics (ciprofloxacin or rifampin) recommended by the current guidelines.

Exploratory Network Meta Regression Analysis of Stroke Prevention in Atrial Fibrillation Fails to Identify Any Interactions with Treatment Effect

BACKGROUND

Patients with atrial fibrillation are at a greater risk of stroke and therefore the main goal for treatment of patients with atrial fibrillation is to prevent stroke from occurring. There are a number of different stroke prevention treatments available to include warfarin and novel oral anticoagulants. Previous network meta-analyses of novel oral anticoagulants for stroke prevention in atrial fibrillation acknowledge the limitation of heterogeneity across the included trials but have not explored the impact of potentially important treatment modifying covariates.

OBJECTIVES

To explore potentially important treatment modifying covariates using network meta-regression analyses for stroke prevention in atrial fibrillation.

METHODS

We performed a network meta-analysis for the outcome of ischaemic stroke and conducted an exploratory regression analysis considering potentially important treatment modifying covariates. These covariates included the proportion of patients with a previous stroke, proportion of males, mean age, the duration of study follow-up and the patients underlying risk of ischaemic stroke.

RESULTS

None of the covariates explored impacted relative treatment effects relative to placebo. Notably, the exploration of 'study follow-up' as a covariate supported the assumption that difference in trial durations is unimportant in this indication despite the variation across trials in the network.

CONCLUSION

This study is limited by the quantity of data available. Further investigation is warranted, and, as justifying further trials may be difficult, it would be desirable to obtain individual patient level data (IPD) to facilitate an effort to relate treatment effects to IPD covariates in order to investigate heterogeneity. Observational data could also be examined to establish if there are potential trends elsewhere. The approach and methods presented have potentially wide applications within any indication as to highlight the potential benefit of extending decision problems to include additional comparators outside of those of primary interest to allow for the exploration of heterogeneity.

An overview of methods for network meta-analysis using individual participant data: when do benefits arise?

Network meta-analysis (NMA) is a common approach to summarizing relative treatment effects from randomized trials with different treatment comparisons. Most NMAs are based on published aggregate data (AD) and have limited possibilities for investigating the extent of network consistency and between-study heterogeneity. Given that individual participant data (IPD) are considered the gold standard in evidence synthesis, we explored statistical methods for IPD-NMA and investigated their potential advantages and limitations, compared with AD-NMA. We discuss several one-stage random-effects NMA models that account for within-trial imbalances, treatment effect modifiers, missing response data and longitudinal responses. We illustrate all models in a case study of 18 antidepressant trials with a continuous endpoint (the Hamilton Depression Score). All trials suffered from drop-out; missingness of longitudinal responses ranged from 21 to 41% after 6 weeks follow-up. Our results indicate that NMA based on IPD may lead to increased precision of estimated treatment effects. Furthermore, it can help to improve network consistency and explain between-study heterogeneity by adjusting for participant-level effect modifiers and adopting more advanced models for dealing with missing response data. We conclude that implementation of IPD-NMA should be considered when trials are affected by substantial drop-out rate, and when treatment effects are potentially influenced by participant-level covariates.

Assumptions of Mixed Treatment Comparisons in Health Technology Assessments - Challenges and Possible Steps for Practical Application

The validity of mixed treatment comparisons (MTCs), also called network meta-analysis, relies on whether it is reasonable to accept the underlying assumptions on similarity, homogeneity, and consistency. The aim of this paper is to propose a practicable approach to addressing the underlying assumptions of MTCs. Using data from clinical studies of antidepressants included in a health technology assessment (HTA), we present a stepwise approach to dealing with challenges related to checking the above assumptions and to judging the robustness of the results of an MTC. At each step, studies that were dissimilar or contributed to substantial heterogeneity or inconsistency were excluded from the primary analysis. In a comparison of the MTC estimates from the consistent network with the MTC estimates from the homogeneous network including inconsistencies, few were affected by notable changes; that is, a change in effect size (factor 2), direction of effect or statistical significance. Considering the small proportion of studies excluded from the network due to inconsistency, as well as the number of notable changes, the MTC results were deemed sufficiently robust. In the absence of standard methods, our approach to checking assumptions in MTCs may inform other researchers in need of practical options, particularly in HTA.

The effect of door-to-balloon delay in primary percutaneous coronary intervention on clinical outcomes of STEMI: a systematic review and meta-analysis protocol

BACKGROUND

Acute myocardial infarction (AMI) is a medical emergency in which sudden occlusion of coronary artery(ies) results in ischemia and necrosis of the cardiac tissues. Reperfusion therapies that aim at reopening the occluded artery remain the mainstay of treatment for AMI. Primary percutaneous coronary intervention (PCI), which enables the restoration of blood flow by reopening the occluded artery(ies) via a catheter with an inflatable balloon, is currently the preferred treatment for AMI with ST segment elevation (STEMI). The door-to-balloon (D2B) delay refers to the time interval counting from the arrival of a patient with STEMI at a hospital to the time of the balloon inflation (or stent deployment) that reopens the occluded artery(ies). Reducing this delay in primary PCI is thought to be an important strategy toward achieving better patient outcomes. Unfortunately, significant reduction of D2B delay in the USA over the last decade has not been shown to be associated with improved STEMI mortality. It has been suggested that the lack of impact could be due to the expanding use of primary PCI in STEMI as well as the survival cohort effect, leading to a shift toward a higher risk population receiving the procedure. Others have suggested that reduction in D2B delay may not be as impactful as expected, given that it only represents a small fraction of the total ischemic time. Although most existing evidence have pointed to the presence of a beneficial effect of shorter D2B delay, some inconsistencies however exist. This study aims to synthesize available evidence in order to answer the following questions: (1) what is the overall effect of D2B delay on clinical outcomes in patients with STEMI treated with primary PCI? (2) What factors explain the differences of the effect estimates among the studies? (3) What are the important strength and limitation of the existing body of evidence?

METHOD

We will search PubMed/MEDLINE, EMBASE, ClinicalTrials.gov, WHO International Clinical Trials Registry, CINAHL Database, and the Cochrane Library using a predefined search strategy. Other sources of literature will include proceedings from the European Society of Cardiology, the American College of Cardiology, the American Heart Association, the EUROPCR, and the ProQuest Dissertations and Theses Database. We will include data from observational studies (case-control and cohort study design) and randomized control trials (that have investigated the relationship of D2B time and clinical outcome(s) in an adult (older than 18) STEMI population). Mortality (cardiac related and all-cause) and incidence heart failure (HF) have been prioritized as the primary outcomes. All eligible studies will be assessed for risk of bias using the Risk Of Bias in Non-randomized Studies - of Interventions tool. The Grading of Recommendations, Assessment, and Evaluation (GRADE) framework will be used to report the quality of evidence and strength of recommendations. We will proceed to analyze the data quantitatively if the pre-specified conditions are satisfied.

DISCUSSION

Recent discussion on the negative findings of improved D2B delay over time being unrelated to better STEMI outcomes at the population level has reminded us of an important knowledge gap we have on this domain. This systematic review will serve to address some of these key questions not previously examined. Answers to these questions could clarify the controversies and offer empirical support for or against the suggested hypotheses.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015026069.

Clinical effectiveness of bisphosphonates for the prevention of fragility fractures: A systematic review and network meta-analysis

OBJECTIVES

To assess the relative efficacy of bisphosphonates (alendronate, risedronate, ibandronate and zoledronic acid) for the treatment of osteoporosis using network meta-analysis (NMA).

METHODS

A systematic review of the literature was conducted using PRISMA guidelines. A network meta-analysis was used to determine the relative efficacy of treatments on four fracture outcomes (vertebral, non-vertebral, hip and wrist) and percentage change in femoral neck bone mineral density (BMD). Treatment effects were modelled using an exchangeable treatment effects model. Heterogeneity in treatment effects was explored by considering potential treatment effect modifiers using meta-regression. Where appropriate, inconsistency between direct and indirect evidence was assessed using node-splitting.

RESULTS

46 randomised controlled trials (RCTs) were identified. Twenty seven RCTs provided fracture data and 35 RCTs provided BMD data for analysis. Zoledronic acid was associated with the greatest treatment effect on vertebral fractures (HR 0.41, 95% CrI: 0.28, 0.56) and percentage change in BMD (3.21, 95%: CrI 2.52, 3.86) compared to placebo. The greatest treatment effect on non-vertebral and wrist fractures was given by risedronate (HR 0.72, 95%: CrI 0.53, 0.89 and HR 0.77, 95%: CrI 0.44, 1.24, respectively). For hip fractures the greatest treatment effect was given by alendronate (HR 0.78, 95% CrI: 0.44, 1.30).

CONCLUSIONS

All treatments examined were associated with beneficial effects on fractures and femoral neck BMD relative to placebo. For vertebral fractures and percentage change in femoral neck BMD the treatment effects were statistically significant for all treatments. Pairwise comparisons between treatments indicated that no active treatment was statistically significantly more effective than any other active treatment for fracture outcomes. There was some heterogeneity in treatment effects between studies suggesting differential treatment effects according to study characteristics; however, there was no evidence of differential treatment effects with respect to gender and age.

Survival and long-term outcomes in late-onset Pompe disease following alglucosidase alfa treatment: a systematic review and meta-analysis

A number of studies have assessed the efficacy of alglucosidase alfa as an enzyme replacement therapy (ERT) on motor and respiratory endpoints in patients with late-onset Pompe disease (LOPD). A previous review evaluated the clinical efficacy and safety of alglucosidase alfa; however, it is difficult to draw inferences from individual studies due to small patient populations, particularly in evaluating the benefit on survival. To evaluate the current evidence on the long-term efficacy of alglucosidase alfa with regard to survival, motor, and respiratory function in patients with LOPD in relation to the natural progression of the disease, a new systematic literature review was performed identifying studies that assessed either mortality, percent predicted forced vital capacity (% FVC), or the 6-min walk test (6MWT) among treated and untreated LOPD patients. Patient overlap was avoided by removing smaller studies or ensuring the use of only one conflicting study per outcome. Mortality was modeled using Poisson models for each treatment group. Outcomes were modeled using first- and second-order fractional polynomial meta-analysis with fixed- and random-effects. Meta-regression was used to explore sources of heterogeneity. Twenty-two publications pertaining to 19 studies/trials were selected, including 438 patients when accounting for overlaps, with the average study duration being 45.7 months. Patients treated with alglucosidase alfa in these studies had a nearly five-fold lower mortality rate than untreated patients (rate ratio: 0.21; 95 % credible interval: 0.11, 0.41). On average, % FVC declined consistently among untreated patients, including a 2.3 % decline after 12 months follow-up and 6.2 % decline after 48 months. This is in contrast to alglucosidase alfa-treated patients, who, on average, improved rapidly, with an increase of 1.4 % FVC after 2 months, followed by a slow regression back to baseline over a three-year period. Nonetheless, the relative difference between those treated and not grew over time, from 4.5 % FVC after 12 months to 6 % FVC after 48 months. In the 6MWT, alglucosidase alfa-treated patients on average had the largest improvement over the first 20 months of treatment of approximately 50 meters increase over baseline, with its substantial stabilization in the following years. By comparison, untreated patients do not show 6MWT improvement over time. Alglucosidase alfa has a beneficial effect in LOPD patients as demonstrated by improvements in survival and ambulation maintained over time, as well as prevention of deterioration in respiratory function.

Systematic review with network meta-analysis: comparative effectiveness and safety of strategies for preventing NSAID-associated gastrointestinal toxicity

BACKGROUND

Many strategies are used to prevent nonsteroidal anti-inflammatory drug (NSAID)-associated gastrointestinal toxicity, but the comparative effectiveness remains unclear.

AIM

To evaluate the comparative effectiveness of clinical strategies for preventing gastrointestinal toxicity induced by NSAIDs.

METHODS

MEDLINE, EMBASE and the Cochrane Library (from their inception to May 2015) were searched for randomised controlled trials comparing the risk of gastrointestinal adverse events in patients taking nonselective NSAIDs, selective cyclooxygenase(COX)-2 inhibitors or nonselective NSAIDs/COX-2 inhibitors plus gastroprotective agents [proton pump inhibitors (PPIs), histamine-2 receptor antagonists, misoprostol]. Both pairwise meta-analysis and Bayesian network meta-analysis were performed.

RESULTS

Analyses were based on 82 trials including 125 053 participants. Network meta-analysis demonstrated that selective COX-2 inhibitors + PPIs [Risk ratio (RR), 95% Credible Interval (CrI): ulcer complications 0.07, 0.02-0.18], selective COX-2 inhibitors (RR, 95% CrI: ulcer complications 0.25, 0.15- 0.38; symptomatic ulcer 0.12, 0.04-0.30), nonselective NSAIDs + PPIs (RR, 95% CrI: ulcer complications 0.28, 0.18-0.41; symptomatic ulcer 0.11, 0.04-0.23), nonselective NSAIDs + misoprostol (RR, 95% CrI: ulcer complications 0.47, 0.24-0.81; symptomatic ulcer 0.41, 0.13-1.00) were associated with significantly lower risk of clinical gastrointestinal events compared with nonselective NSAIDs. For all effectiveness endpoints, selective COX-2 inhibitors + PPIs was associated with the lowest absolute event probability and the highest rank, followed by selective COX-2 inhibitors and thirdly by nonselective NSAIDs + PPIs.

CONCLUSION

The combination of selective COX-2 inhibitors plus PPIs provides the best gastrointestinal protection, followed by selective COX-2 inhibitors, and thirdly by nonselective NSAIDs plus PPIs.

Fracture risk in oral glucocorticoid users: a Bayesian meta-regression leveraging control arms of osteoporosis clinical trials

Little data exist on the frequency of fracture among oral glucocorticoid users. We examined the effect of oral glucocorticoids on fracture incidence using data from randomized controlled trials. Patients starting glucocorticoids had a higher probability of fracture and decline in bone mineral density compared to chronic glucocorticoid users.

INTRODUCTION

Oral glucocorticoids (GCs) are the leading cause of secondary osteoporosis. However, there have been few studies that quantify the rate of fracture among GC users. We sought to provide a pooled estimate of fracture risk from randomized controlled trials (RCTs) of GC-treated patients.

METHODS

We updated a MEDLINE search published by the American College of Rheumatology through to March 2015 and identified RCTs of osteoporosis therapies that reported fracture and bone mineral density (BMD) among oral GC users. We restricted the analysis to placebo or control arms. RCT arms were stratified by GC exposure at enrolment to GC initiators (≤6 months) and chronic GC users (>6 months). Bayesian meta-regression was used to estimate the annual probability of vertebral fracture (primary), non-vertebral fracture and percentage change in lumbar spine and femoral neck BMD.

RESULTS

The annual incidence of vertebral and non-vertebral fracture was 5.1 % (95 % CrI = 2.8-8.2) and 2.5 % (95 % CrI = 1.2--4.2) among GC initiators, and 3.2 % (95 % CrI = 1.8-5.0) and 3.0 % (95 % CrI = 0.8-5.9) among chronic GC users. Our meta-regression identified a non-significant effect of group-level variables (mean age, mean BMD, mean GC daily dose, patients with previous vertebral fractures, proportion of women and adjuvant used) on vertebral fracture rate.

CONCLUSION

Our study found higher vertebral fracture incidence among GC initiators, yet a relative decline in fracture incidence with longer exposure. Our findings suggest that fracture incidence among oral GC users may be more common than previously estimated. Optimizing GC-induced osteoporosis management during early exposure to GC is essential to prevent fractures.

Comparative safety and efficacy of vasopressors for mortality in septic shock: A network meta-analysis

INTRODUCTION

Septic shock is a life-threatening condition requiring vasopressor agents to support the circulatory system. Several agents exist with choice typically guided by the specific clinical scenario. We used a network meta-analysis approach to rate the comparative efficacy and safety of vasopressors for mortality and arrhythmia incidence in septic shock patients.

METHODS

We performed a comprehensive electronic database search including Medline, Embase, Science Citation Index Expanded and the Cochrane database. Randomised trials investigating vasopressor agents in septic shock patients and specifically assessing 28-day mortality or arrhythmia incidence were included. A Bayesian network meta-analysis was performed using Markov chain Monte Carlo methods.

RESULTS

Thirteen trials of low to moderate risk of bias in which 3146 patients were randomised were included. There was no pairwise evidence to suggest one agent was superior over another for mortality. In the network meta-analysis, vasopressin was significantly superior to dopamine (OR 0.68 (95% CI 0.5 to 0.94)) for mortality. For arrhythmia incidence, standard pairwise meta-analyses confirmed that dopamine led to a higher incidence of arrhythmias than norepinephrine (OR 2.69 (95% CI 2.08 to 3.47)). In the network meta-analysis, there was no evidence of superiority of one agent over another.

CONCLUSIONS

In this network meta-analysis, vasopressin was superior to dopamine for 28-day mortality in septic shock. Existing pairwise information supports the use of norepinephrine over dopamine. Our findings suggest that dopamine should be avoided in patients with septic shock and that other vasopressor agents should continue to be based on existing guidelines and clinical judgement of the specific presentation of the patient.

Cost-Effectiveness of Ivermectin 1% Cream in Adults with Papulopustular Rosacea in the United States

BACKGROUND

Papulopustular rosacea is a chronic skin disease involving central facial erythema in combination with papules and pustules. Papulopustular rosacea is treated with topical, systemic, or a combination of topical and systemic therapies. Currently approved topical therapies include azelaic acid gel/cream/foam twice daily (BID) and metronidazole cream/gel/lotion BID. Ivermectin 1% cream once daily (QD) is a new topical agent for the treatment of papulopustular rosacea that has been approved for the management of inflammatory lesions of rosacea and offers an alternative to current treatments.

OBJECTIVE

To evaluate the cost-effectiveness of ivermectin 1% cream QD compared with current topical treatments in order to understand the cost of adding ivermectin as a treatment option that would bring additional clinical benefit for adults with papulopustular rosacea in the United States.

METHODS

The cost-effectiveness of ivermectin 1% cream QD was compared with metronidazole 0.75% cream BID and azelaic acid 15% gel BID for adults in the United States with moderate-to-severe papulopustular rosacea using a Markov cohort state transition structure with 2 mutually exclusive health states (rosacea and no rosacea) and 5 phases. Patients could succeed or fail to respond to treatment and experience a relapse after treatment success. The model took a health care payer perspective (direct medical costs of topical and/or systemic therapy plus health care costs for physician and specialist visits) and used a 3-year time horizon. The model was run for a cohort of 1,000 patients. Costs (2014 U.S. dollars) and benefits (disease-free days and quality-adjusted life-years [QALYs]) were discounted at a rate of 3% per annum. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER) and measured in terms of incremental cost per QALY gained (estimated from health state utilities for patients with and without rosacea). Univariate and probabilistic sensitivity analyses (PSA) were conducted to assess the robustness of model outcomes.

RESULTS

Compared with metronidazole 0.75% cream BID, ivermectin 1% cream QD was associated with higher costs but provided greater clinical benefit, with an ICER of $13,211 per QALY gained. For a cohort of 1,000 patients, ivermectin 1% cream QD provided an additional 72,922 disease-free days (200 years) over a 3-year period compared with metronidazole 0.75% cream BID, leading to a lower cost per disease-free day for ivermectin 1% cream QD ($4.54) compared with metronidazole 0.75% cream BID ($4.85). Ivermectin 1% cream QD was associated with lower total costs and greater clinical benefit compared with azelaic acid 15% gel BID at year 3 and dominated this treatment. After 3 years, ivermectin 1% cream QD was associated with the lowest health care costs ($62,767 compared with $73,284 for metronidazole 0.75% cream BID and $77,208 for azelaic acid 15% gel BID), reflecting a 15% reduction in physician visit costs, when compared with metronidazole 0.75% cream BID, and almost a 20% reduction, when compared with azelaic acid 15% gel BID. The univariate sensitivity analyses indicated that the results are sensitive to the time horizon selected: the longer the time horizon, the more beneficial the results for ivermectin 1% cream QD relative to the comparators, although even at 1 year, ivermectin 1% cream QD dominated azelaic acid 15% gel BID. The PSA suggested that ivermectin 1% cream QD was the most likely treatment to be cost-effective at a willingness-to-pay threshold of $15,000 and above.

CONCLUSIONS

Ivermectin 1% cream QD had favorable incremental cost-effectiveness when compared with metronidazole 0.75% cream BID and dominated azelaic acid 15% gel BID in the treatment of papulopustular rosacea in the United States. Therefore, ivermectin 1% cream QD may be a good first-line treatment for papulopustular rosacea, providing additional clinical benefit at no or low additional cost.

DISCLOSURES

This study was sponsored by Galderma Laboratories. The sponsor was involved in the design of the model structure but not in the collection of the data used to populate the model. Manuscript preparation was also funded by Galderma. Taieb is an investigator and advisor for Galderma. Gold is an investigator for Galderma. Feldman is a consultant and speaker for Galderma and has received grants from Galderma. Dansk and Bertranou received a research grant from Galderma to conduct this study. Dansk and Bertranou contributed to the design of the model structure, the sourcing and inputting of the data, and the interpretation of the results. Taieb, Feldman, and Gold contributed to the interpretation of the results. All authors reviewed draft versions of the manuscript and gave permission for the submission of the final version.

Management strategies for pancreatic pseudocysts

BACKGROUND

Pancreatic pseudocysts are walled-off peripancreatic fluid collections. There is considerable uncertainty about how pancreatic pseudocysts should be treated.

OBJECTIVES

To assess the benefits and harms of different management strategies for pancreatic pseudocysts.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library 2015, Issue 9, and MEDLINE, EMBASE, Science Citation Index Expanded, and trials registers until September 2015. We also searched the references of included trials and contacted trial authors.

SELECTION CRITERIA

We only considered randomised controlled trials (RCTs) of people with pancreatic pseudocysts, regardless of size, presence of symptoms, or aetiology. We placed no restrictions on blinding, language, or publication status of the trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials and extracted data. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CI) with RevMan 5, based on an available-case analysis for direct comparisons, using fixed-effect and random-effect models. We also conducted indirect comparisons (rather than network meta-analysis), since there were no outcomes for which direct and indirect evidence were available.

MAIN RESULTS

We included four RCTs, with 177 participants, in this review. After one participant was excluded, 176 participants were randomised to endoscopic ultrasound (EUS)-guided drainage (88 participants), endoscopic drainage (44 participants), EUS-guided drainage with nasocystic drainage (24 participants), and open surgical drainage (20 participants). The comparisons included endoscopic drainage versus EUS-guided drainage (two trials), EUS-guided drainage with nasocystic drainage versus EUS-guided drainage alone (one trial), and open surgical drainage versus EUS-guided drainage (one trial). The participants were mostly symptomatic, with pancreatic pseudocysts resulting from acute and chronic pancreatitis of varied aetiology. The mean size of the pseudocysts ranged between 70 mm and 155 mm across studies. Although the trials appeared to include similar types of participants for all comparisons, we were unable to assess this statistically, since there were no direct and indirect results for any of the comparisons.All the trials were at unclear or high risk of bias, and the overall quality of evidence was low or very low for all outcomes. One death occurred in the endoscopic drainage group (1/44; 2.3%), due to bleeding. There were no deaths in the other groups. The differences in the serious adverse events were imprecise. Short-term health-related quality of life (HRQoL; four weeks to three months) was worse (MD -21.00; 95% CI -33.21 to -8.79; participants = 40; studies = 1; range: 0 to 100; higher score indicates better) and the costs were higher in the open surgical drainage group than the EUS-guided drainage group (MD 8040 USD; 95% CI 3020 to 13,060; participants = 40; studies = 1). There were fewer adverse events in the EUS-guided drainage with nasocystic drainage group than in the EUS-guided drainage alone (OR 0.20; 95% CI 0.06 to 0.73; participants = 47; studies = 1), or the endoscopic drainage group (indirect comparison: OR 0.08; 95% CI 0.01 to 0.61). Participants with EUS-guided drainage with nasocystic drainage also had shorter hospital stays compared to EUS-guided drainage alone (MD -8.10 days; 95% CI -9.79 to -6.41; participants = 47; studies = 1), endoscopic drainage (indirect comparison: MD -7.10 days; 95% CI -9.38 to -4.82), or open surgical drainage group (indirect comparison: MD -12.30 days; 95% CI -14.48 to -10.12). The open surgical drainage group had longer hospital stays than the EUS-guided drainage group (MD 4.20 days; 95% CI 2.82 to 5.58; participants = 40; studies = 1); the endoscopic drainage group had longer hospital stays than the open drainage group (indirect comparison: -5.20 days; 95% CI -7.26 to -3.14). The need for additional invasive interventions was higher for the endoscopic drainage group than the EUS-guided drainage group (OR 11.13; 95% CI 2.85 to 43.44; participants = 89; studies = 2), and the open drainage group (indirect comparison: OR 23.69; 95% CI 1.40 to 400.71). The differences between groups were imprecise for the other comparisons that could be performed. None of the trials reported long-term mortality, medium-term HRQoL (three months to one year), long-term HRQoL (longer than one year), time-to-return to normal activities, or time-to-return to work.

AUTHORS' CONCLUSIONS

Very low-quality evidence suggested that the differences in mortality and serious adverse events between treatments were imprecise. Low-quality evidence suggested that short-term HRQoL (four weeks to three months) was worse, and the costs were higher in the open surgical drainage group than in the EUS-guided drainage group. Low-quality or very low-quality evidence suggested that EUS-guided drainage with nasocystic drainage led to fewer adverse events than EUS-guided or endoscopic drainage, and shorter hospital stays when compared to EUS-guided drainage, endoscopic drainage, or open surgical drainage, while EUS-guided drainage led to shorter hospital stays than open surgical drainage. Low-quality evidence suggested that there was a higher need for additional invasive procedures with endoscopic drainage than EUS-guided drainage, while it was lower in the open surgical drainage than in the endoscopic drainage group.Further RCTs are needed to compare EUS-guided drainage, with or without nasocystic drainage, in symptomatic patients with pancreatic pseudocysts that require treatment. Future trials should include patient-oriented outcomes such as mortality, serious adverse events, HRQoL, hospital stay, return-to-normal activity, number of work days lost, and the need for additional procedures, for a minimum follow-up period of two to three years.

Management strategies for pancreatic pseudocysts

BACKGROUND

Pancreatic pseudocysts are walled-off peripancreatic fluid collections. There is considerable uncertainty about how pancreatic pseudocysts should be treated.

OBJECTIVES

To assess the benefits and harms of different management strategies for pancreatic pseudocysts.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library 2015, Issue 9, and MEDLINE, EMBASE, Science Citation Index Expanded, and trials registers until September 2015. We also searched the references of included trials and contacted trial authors.

SELECTION CRITERIA

We only considered randomised controlled trials (RCTs) of people with pancreatic pseudocysts, regardless of size, presence of symptoms, or aetiology. We placed no restrictions on blinding, language, or publication status of the trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials and extracted data. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CI) with RevMan 5, based on an available-case analysis for direct comparisons, using fixed-effect and random-effect models. We also conducted indirect comparisons (rather than network meta-analysis), since there were no outcomes for which direct and indirect evidence were available.

MAIN RESULTS

We included four RCTs, with 177 participants, in this review. After one participant was excluded, 176 participants were randomised to endoscopic ultrasound (EUS)-guided drainage (88 participants), endoscopic drainage (44 participants), EUS-guided drainage with nasocystic drainage (24 participants), and open surgical drainage (20 participants). The comparisons included endoscopic drainage versus EUS-guided drainage (two trials), EUS-guided drainage with nasocystic drainage versus EUS-guided drainage alone (one trial), and open surgical drainage versus EUS-guided drainage (one trial). The participants were mostly symptomatic, with pancreatic pseudocysts resulting from acute and chronic pancreatitis of varied aetiology. The mean size of the pseudocysts ranged between 70 mm and 155 mm across studies. Although the trials appeared to include similar types of participants for all comparisons, we were unable to assess this statistically, since there were no direct and indirect results for any of the comparisons.All the trials were at unclear or high risk of bias, and the overall quality of evidence was low or very low for all outcomes. One death occurred in the endoscopic drainage group (1/44; 2.3%), due to bleeding. There were no deaths in the other groups. The differences in the serious adverse events were imprecise. Short-term health-related quality of life (HRQoL; four weeks to three months) was worse (MD -21.00; 95% CI -33.21 to -8.79; participants = 40; studies = 1; range: 0 to 100; higher score indicates better) and the costs were higher in the open surgical drainage group than the EUS-guided drainage group (MD 8040 USD; 95% CI 3020 to 13,060; participants = 40; studies = 1). There were fewer adverse events in the EUS-guided drainage with nasocystic drainage group than in the EUS-guided drainage alone (OR 0.20; 95% CI 0.06 to 0.73; participants = 47; studies = 1), or the endoscopic drainage group (indirect comparison: OR 0.08; 95% CI 0.01 to 0.61). Participants with EUS-guided drainage with nasocystic drainage also had shorter hospital stays compared to EUS-guided drainage alone (MD -8.10 days; 95% CI -9.79 to -6.41; participants = 47; studies = 1), endoscopic drainage (indirect comparison: MD -7.10 days; 95% CI -9.38 to -4.82), or open surgical drainage group (indirect comparison: MD -12.30 days; 95% CI -14.48 to -10.12). The open surgical drainage group had longer hospital stays than the EUS-guided drainage group (MD 4.20 days; 95% CI 2.82 to 5.58; participants = 40; studies = 1); the endoscopic drainage group had longer hospital stays than the open drainage group (indirect comparison: -5.20 days; 95% CI -7.26 to -3.14). The need for additional invasive interventions was higher for the endoscopic drainage group than the EUS-guided drainage group (OR 11.13; 95% CI 2.85 to 43.44; participants = 89; studies = 2), and the open drainage group (indirect comparison: OR 23.69; 95% CI 1.40 to 400.71). The differences between groups were imprecise for the other comparisons that could be performed. None of the trials reported long-term mortality, medium-term HRQoL (three months to one year), long-term HRQoL (longer than one year), time-to-return to normal activities, or time-to-return to work.

AUTHORS' CONCLUSIONS

Very low-quality evidence suggested that the differences in mortality and serious adverse events between treatments were imprecise. Low-quality evidence suggested that short-term HRQoL (four weeks to three months) was worse, and the costs were higher in the open surgical drainage group than in the EUS-guided drainage group. Low-quality or very low-quality evidence suggested that EUS-guided drainage with nasocystic drainage led to fewer adverse events than EUS-guided or endoscopic drainage, and shorter hospital stays when compared to EUS-guided drainage, endoscopic drainage, or open surgical drainage, while EUS-guided drainage led to shorter hospital stays than open surgical drainage. Low-quality evidence suggested that there was a higher need for additional invasive procedures with endoscopic drainage than EUS-guided drainage, while it was lower in the open surgical drainage than in the endoscopic drainage group.Further RCTs are needed to compare EUS-guided drainage, with or without nasocystic drainage, in symptomatic patients with pancreatic pseudocysts that require treatment. Future trials should include patient-oriented outcomes such as mortality, serious adverse events, HRQoL, hospital stay, return-to-normal activity, number of work days lost, and the need for additional procedures, for a minimum follow-up period of two to three years.

Disconnected by design: analytic approach in treatment networks having no common comparator

In a network meta-analysis, comparators of interest are ideally connected either directly or via one or more common comparators. However, in some therapeutic areas, the evidence base can produce networks that are disconnected, in which there is neither direct evidence nor an indirect route for comparing certain treatments within the network. Disconnected networks may occur when there is no accepted standard of care, when there has been a major paradigm shift in treatment, when use of a standard of care or placebo is debated, when a product receives orphan drug designation, or when there is a large number of available treatments and many accepted standards of care. These networks pose a challenge to decision makers and clinicians who want to estimate the relative efficacy and safety of newly available agents against alternatives. A currently recommended approach is to insert a distribution for the unknown treatment effect(s) into a network meta-analysis model of treatment effect. In this paper, we describe this approach along with two alternative Bayesian models that can accommodate disconnected networks. Additionally, we present a theoretical framework to guide the choice between modeling approaches. This paper presents researchers with the tools and framework for selecting appropriate models for indirect comparison of treatment efficacies when challenged with a disconnected framework. Copyright © 2016 John Wiley & Sons, Ltd.

Cardiovascular and Renal Outcomes of Renin-Angiotensin System Blockade in Adult Patients with Diabetes Mellitus: A Systematic Review with Network Meta-Analyses

BACKGROUND

Medications aimed at inhibiting the renin-angiotensin system (RAS) have been used extensively for preventing cardiovascular and renal complications in patients with diabetes, but data that compare their clinical effectiveness are limited. We aimed to compare the effects of classes of RAS blockers on cardiovascular and renal outcomes in adults with diabetes.

METHODS AND FINDINGS

Eligible trials were identified by electronic searches in PubMed/MEDLINE and the Cochrane Database of Systematic Reviews (1 January 2004 to 17 July 2014). Interventions of interest were angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and direct renin (DR) inhibitors. The primary endpoints were cardiovascular mortality, myocardial infarction, and stroke-singly and as a composite endpoint, major cardiovascular outcome-and end-stage renal disease [ESRD], doubling of serum creatinine, and all-cause mortality-singly and as a composite endpoint, progression of renal disease. Secondary endpoints were angina pectoris and hospitalization for heart failure. In all, 71 trials (103,120 participants), with a total of 14 different regimens, were pooled using network meta-analyses. When compared with ACE inhibitor, no other RAS blocker used in monotherapy and/or combination was associated with a significant reduction in major cardiovascular outcomes: ARB (odds ratio [OR] 1.02; 95% credible interval [CrI] 0.90-1.18), ACE inhibitor plus ARB (0.97; 95% CrI 0.79-1.19), DR inhibitor plus ACE inhibitor (1.32; 95% CrI 0.96-1.81), and DR inhibitor plus ARB (1.00; 95% CrI 0.73-1.38). For the risk of progression of renal disease, no significant differences were detected between ACE inhibitor and each of the remaining therapies: ARB (OR 1.10; 95% CrI 0.90-1.40), ACE inhibitor plus ARB (0.97; 95% CrI 0.72-1.29), DR inhibitor plus ACE inhibitor (0.99; 95% CrI 0.65-1.57), and DR inhibitor plus ARB (1.18; 95% CrI 0.78-1.84). No significant differences were showed between ACE inhibitors and ARBs with respect to all-cause mortality, cardiovascular mortality, myocardial infarction, stroke, angina pectoris, hospitalization for heart failure, ESRD, or doubling serum creatinine. Findings were limited by the clinical and methodological heterogeneity of the included studies. Potential inconsistency was identified in network meta-analyses of stroke and angina pectoris, limiting the conclusiveness of findings for these single endpoints.

CONCLUSIONS

In adults with diabetes, comparisons of different RAS blockers showed similar effects of ACE inhibitors and ARBs on major cardiovascular and renal outcomes. Compared with monotherapies, the combination of an ACE inhibitor and an ARB failed to provide significant benefits on major outcomes. Clinicians should discuss the balance between benefits, costs, and potential harms with individual diabetes patients before starting treatment.

REVIEW REGISTRATION

PROSPERO CRD42014014404.

GetReal in network meta-analysis: a review of the methodology

Pairwise meta-analysis is an established statistical tool for synthesizing evidence from multiple trials, but it is informative only about the relative efficacy of two specific interventions. The usefulness of pairwise meta-analysis is thus limited in real-life medical practice, where many competing interventions may be available for a certain condition and studies informing some of the pairwise comparisons may be lacking. This commonly encountered scenario has led to the development of network meta-analysis (NMA). In the last decade, several applications, methodological developments, and empirical studies in NMA have been published, and the area is thriving as its relevance to public health is increasingly recognized. This article presents a review of the relevant literature on NMA methodology aiming to pinpoint the developments that have appeared in the field. Copyright © 2016 John Wiley & Sons, Ltd.

'Arm-based' parameterization for network meta-analysis

We present an alternative to the contrast‐based parameterization used in a number of publications for network meta‐analysis. This alternative “arm‐based” parameterization offers a number of advantages: it allows for a “long” normalized data structure that remains constant regardless of the number of comparators; it can be used to directly incorporate individual patient data into the analysis; the incorporation of multi‐arm trials is straightforward and avoids the need to generate a multivariate distribution describing treatment effects; there is a direct mapping between the parameterization and the analysis script in languages such as WinBUGS and finally, the arm‐based parameterization allows simple extension to treatment‐specific random treatment effect variances.

We validated the parameterization using a published smoking cessation dataset. Network meta‐analysis using arm‐ and contrast‐based parameterizations produced comparable results (with means and standard deviations being within +/− 0.01) for both fixed and random effects models. We recommend that analysts consider using arm‐based parameterization when carrying out network meta‐analyses. © 2015 The Authors Research Synthesis Methods Published by John Wiley & Sons Ltd.

Questionable assumptions hampered interpretation of a network meta-analysis of primary care depression treatments

OBJECTIVES

We aimed to evaluate the underlying assumptions of a network meta-analysis investigating which depression treatment works best in primary care and to highlight challenges and pitfalls of interpretation under consideration of these assumptions.

STUDY DESIGN AND SETTING

We reviewed 100 randomized trials investigating pharmacologic and psychological treatments for primary care patients with depression. Network meta-analysis was carried out within a frequentist framework using response to treatment as outcome measure. Transitivity was assessed by epidemiologic judgment based on theoretical and empirical investigation of the distribution of trial characteristics across comparisons. Homogeneity and consistency were investigated by decomposing the Q statistic.

RESULTS

There were important clinical and statistically significant differences between "pure" drug trials comparing pharmacologic substances with each other or placebo (63 trials) and trials including a psychological treatment arm (37 trials). Overall network meta-analysis produced results well comparable with separate meta-analyses of drug trials and psychological trials. Although the homogeneity and consistency assumptions were mostly met, we considered the transitivity assumption unjustifiable.

CONCLUSION

An exchange of experience between reviewers and, if possible, some guidance on how reviewers addressing important clinical questions can proceed in situations where important assumptions for valid network meta-analysis are not met would be desirable.

Modelling the cost-effectiveness of pharmacotherapy compared with cognitive-behavioural therapy and combination therapy for the treatment of moderate to severe depression in the UK

BACKGROUND

The National Institute of Health and Care Excellence (NICE) in England and Wales recommends the combination of pharmacotherapy and psychotherapy for the treatment of moderate to severe depression. However, the cost-effectiveness analysis on which these recommendations are based has not included psychotherapy as monotherapy as a potential option. For this reason, we aimed to update, augment and refine the existing economic evaluation.

METHOD

We constructed a decision analytic model with a 27-month time horizon. We compared pharmacotherapy with cognitive-behavioural therapy (CBT) and combination treatment for moderate to severe depression in secondary care from a healthcare service perspective. We reviewed the literature to identify relevant evidence and, where possible, synthesized evidence from clinical trials in a meta-analysis to inform model parameters.

RESULTS

The model suggested that CBT as monotherapy was most likely to be the most cost-effective treatment option above a threshold of £ 22,000 per quality-adjusted life year (QALY). It dominated combination treatment and had an incremental cost-effectiveness ratio of £ 20,039 per QALY compared with pharmacotherapy. There was significant decision uncertainty in the probabilistic and deterministic sensitivity analyses.

CONCLUSIONS

Contrary to previous NICE guidance, the results indicated that even for those patients for whom pharmacotherapy is acceptable, CBT as monotherapy may be a cost-effective treatment option. However, this conclusion was based on a limited evidence base, particularly for combination treatment. In addition, this evidence cannot easily be transferred to a primary care setting.

Comparative efficacy and safety of estradiol transdermal preparations for the treatment of vasomotor symptoms in postmenopausal women: an indirect comparison meta-analysis

OBJECTIVE

Divigel and Estrogel are estradiol gels for the treatment of postmenopausal women with moderate to severe vasomotor symptoms. They differ with respect to several factors including estradiol concentration and surface application, and cannot be compared solely on the basis of their estradiol dose. No randomized clinical trials have compared them head to head, but both have been compared with placebo. Therefore, the objective of this study was to conduct a systematic review and network meta-analysis of the two estradiol gels.

METHODS

We performed a comprehensive systematic literature review. One publication reporting on one Divigel trial, three publications reporting on two Estrogel trials, and five publications reporting on other estradiol transdermal preparations were identified. Efficacy outcomes were change from baseline in daily hot flush frequency and change from baseline in daily hot flush severity. Safety outcomes were frequency of treatment-related adverse events (AEs) and frequency of treatment-emergent AEs leading to discontinuation. Bayesian indirect treatment comparison meta-analysis of trial-level data was performed in accordance with the International Society for Pharmacoeconomics and Outcomes Research, Academy of Managed Care Pharmacy, National Pharmaceutical Council (ISPOR-AMCP-NPC) Good Practice Questionnaire. All outcomes were compared with respect to doses of the considered preparations.

RESULTS

For hot flush frequency, Divigel 0.25 mg was similar to Divigel 0.5 mg and to Estrogel 0.75 mg, and was statistically significantly superior to Estrogel 1.5 mg. The largest effect was observed with Divigel 1.0 mg (mean difference of 3.91 hot flushes/wk vs placebo), and was statistically significantly superior to all other interventions. The 1.5 mg Estrogel dose was associated with the smallest estimate of efficacy. For hot flush severity, Divigel 0.25 mg was similar to the efficacy of Divigel 0.5 mg, and for 0.25 mg and 0.5 mg of other estradiol gels, but was statistically inferior to Divigel 1.0 mg, Estrogel 0.75 mg, Estrogel 1.5 mg, and the 1.0 and 1.5 mg doses of all other estradiol gels. The estimated efficacy of Divigel 0.5 mg was similar to that of Estrogel 0.75 mg, Estrogel 1.5 mg, and the 0.25 and 0.5 mg doses of other transdermal estradiol preparations. Risks of treatment-related AEs for Divigel 0.25 mg, Divigel 0.5 mg, Estrogel 0.75 mg, and Estrogel 1.5 mg were similar and all were of a slightly higher risk than placebo. Among these, Divigel 1.0 mg, Estrogel 1.5 mg, and other gels 0.5 mg were statistically significantly less safe than placebo. However, for treatment-emergent AEs leading to discontinuation, none of the gels were associated with statistically significantly higher relative risks compared with placebo. In this study, statistically significant refers to the 95% credible intervals used in the Bayesian Network Analysis.

CONCLUSIONS

Using network meta-analysis for indirect treatment comparison, we have shown that the efficacy of Divigel 0.25 mg, as measured by reduced hot flush frequency and severity, was similar to that of Divigel 0.5 mg and of Estrogel 0.75 and 1.5 mg. Overall, our analysis showed that Divigel 1.0 mg provided the best efficacy profile, but that this treatment was also associated with a higher risk of AEs. The network meta-analysis also showed that treatment with Estrogel 1.5 mg was associated with the smallest estimate of reduction in frequency of hot flushes.

Comparative efficacy and tolerability of first-generation and newer-generation antidepressant medications for depressive disorders in children and adolescents: study protocol for a systematic review and network meta-analysis

INTRODUCTION

Depressive disorders are among the most common psychiatric disorders in children and adolescents, and have adverse effects on their psychosocial functioning. Questions concerning the efficacy and safety of antidepressant medications in the treatment of depression in children and adolescents, led us to integrate the direct and indirect evidence using network meta-analysis to create hierarchies of these drugs.

METHODS AND ANALYSIS

Seven databases with PubMed, EMBASE, the Cochrane Library, Web of Science, CINAHL, LiLACS and PsycINFO will be searched from 1966 to December 2013 (updated to May, 2015). There are no restrictions on language or type of publication. Randomised clinical trials assessing first-generation and newer-generation antidepressant medications against active comparator or placebo as acute treatment for depressive disorders in children and adolescents (under 18 years of age) will be included. The primary outcome for efficacy will be mean improvement in depressive symptoms, as measured by the mean change score of a depression rating scale from baseline to post-treatment. The tolerability of treatment will be defined as side effect discontinuation, as defined by the proportion of patients who discontinued treatment due to adverse events during the trial. We will also assess the secondary outcome for efficacy (response rate), acceptability (all-cause discontinuation) and suicide-related outcomes. We will perform the Bayesian network meta-analyses for all relative outcome measures. Subgroup analyses and sensitivity analyses will be conducted to assess the robustness of the findings.

DISSEMINATION

The network meta-analysis will provide useful information on antidepressant treatment for child and adolescent depression. The results will be disseminated through peer-reviewed publication or conference presentations.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42015016023.

Effectiveness and Implications of Alternative Placebo Treatments: A Systematic Review and Network Meta-analysis of Osteoarthritis Trials

BACKGROUND

Placebo controls are essential in evaluating the effectiveness of medical treatments. Although it is unclear whether different placebo interventions for osteoarthritis vary in efficacy, systematic differences would substantially affect interpretation of the results of placebo-controlled trials.

OBJECTIVE

To evaluate the effects of alternative placebo types on pain outcomes in knee osteoarthritis.

DATA SOURCES

MEDLINE, EMBASE, Web of Science, Google Scholar, and Cochrane Database from inception through 1 June 2015 and unpublished data.

STUDY SELECTION

149 randomized trials of adults with knee osteoarthritis that reported pain outcomes and compared widely used pharmaceuticals against oral, intra-articular, topical, and oral plus topical placebos.

DATA EXTRACTION

Study data were independently double-extracted; study quality was assessed by using the Cochrane risk of bias tool.

DATA SYNTHESIS

Placebo effects that were evaluated by using a network meta-analysis with 4 separate placebo nodes (differential model) showed that intra-articular placebo (effect size, 0.29 [95% credible interval, 0.09 to 0.49]) and topical placebo (effect size, 0.20 [credible interval, 0.02 to 0.38]) had significantly greater effect sizes than did oral placebo. This differential model showed marked differences in the relative efficacies and hierarchy of the active treatments compared with a network model that considered all placebos equivalent. In the model accounting for differential effects, intra-articular and topical therapies were superior to oral treatments in reducing pain. When these differential effects were ignored, oral nonsteroidal anti-inflammatory drugs were superior.

LIMITATIONS

Few studies compared different placebos directly. The study could not decisively conclude whether disease severity and co-interventions systematically differed between trials evaluating different placebos.

CONCLUSION

All placebos are not equal, and some can trigger clinically relevant responses. Differential placebo effects can substantially alter estimates of the relative efficacies of active treatments, an important consideration for the design of clinical trials and interpretation of their results.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Comparison of physical interventions, behavioral interventions, natural health products, and pharmacologics to manage hot flashes in patients with breast or prostate cancer: protocol for a systematic review incorporating network meta-analyses

BACKGROUND

Breast and prostate cancers are the most commonly diagnosed non-dermatologic malignancies in Canada. Agents including endocrine therapies (e.g., aromatase inhibitors, gonadotrophin-releasing hormone analogs, anti-androgens, tamoxifen) and chemotherapy have improved survival for both conditions. As endocrine manipulation is a mainstay of treatment, it is not surprising that hot flashes are a common and troublesome adverse effect. Hot flashes can cause chills, night sweats, anxiety, and insomnia, lessening patients' quality of life. These symptoms impact treatment adherence, worsening prognosis. While short-term estrogen replacement therapy is frequently used to manage hot flashes in healthy menopausal women, its use is contraindicated in breast cancer. Similarly, testosterone replacement therapy is contraindicated in prostate cancer. It is therefore not surprising that non-hormonal pharmacological treatments (anti-depressants, anti-epilectics, anti-hypertensives), physical/behavioral treatments (e.g., acupuncture, yoga/exercise, relaxation techniques, cognitive behavioral therapy), and natural health products (e.g., black cohosh, flax, vitamin E, ginseng) have been studied for control of hot flashes. There is a need to identify which interventions minimize the frequency and severity of hot flashes and their impact on quality of life. This systematic review and network meta-analysis of randomized studies will synthesize available evidence addressing this knowledge gap.

METHODS/DESIGN

An electronic search of Medline, Embase, AMED, PsycINFO, and the Cochrane Register of Controlled Trials has been designed by an information specialist and peer reviewed by a second information specialist. Study selection and data collection will be performed by two reviewers independently. Risk of bias assessments will be completed using the Cochrane Risk of Bias Scale. Outcomes of interest will include validated measures of hot flash severity, hot flash frequency, quality of life, and harms. Bayesian network meta-analyses will be performed where judged appropriate based on review of clinical and methodologic features of included studies.

DISCUSSION

Our review will include a broad range of interventions that patients with breast and prostate cancer have attempted to use to manage hot flashes. Our work will establish the extent of evidence underlying these interventions and will employ an inclusive approach to analysis to inform comparisons between them. Our findings will be shared with Cancer Care Ontario for consideration in the development of guidance related to supportive care in these patients.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO

CRD42015024286.

Comparative effectiveness of psychological treatments for depressive disorders in primary care: network meta-analysis

Background

A variety of psychological interventions to treat depressive disorders have been developed and are used in primary care. In a systematic review, we compared the effectiveness of psychological treatments grouped by theoretical background, intensity of contact with the health care professional, and delivery mode for depressed patients in this setting.

Methods

Randomized trials comparing a psychological treatment with usual care, placebo, another psychological treatment, pharmacotherapy, or a combination treatment in adult depressed primary care patients were identified by database searches up to December 2013. We performed both conventional pairwise meta-analysis and network meta-analysis combining direct and indirect evidence. Outcome measures were response to treatment (primary outcome), remission of symptoms, post-treatment depression scores and study discontinuation.

Results

A total of 37 studies with 7,024 patients met the inclusion criteria. Among the psychological treatments investigated in at least 150 patients face-to-face cognitive behavioral therapy (CBT; OR 1.80; 95 % credible interval 1.35–2.39), face-to-face counselling and psychoeducation (1.65; 1.27–2.13), remote therapist lead CBT (1.87; 1.38–2.53), guided self-help CBT (1.68; 1.22–2.30) and no/minimal contact CBT (1.53; 1.07–2.17) were superior to usual care or placebo, but not face-to-face problem-solving therapy and face-to-face interpersonal therapy. There were no statistical differences between psychological treatments apart from face-to-face interpersonal psychotherapy being inferior to remote therapist-lead CBT (0.60; 0.37–0.95). Remote therapist-led (0.86; 0.21–3.67), guided self-help (0.93; 0.62–1.41) and no/minimal contact CBT (0.85; 0.54–1.36) had similar effects as face-to-face CBT.

Conclusions

The limited available evidence precludes a sufficiently reliable assessment of the comparative effectiveness of psychological treatments in depressed primary care patients. Findings suggest that psychological interventions with a cognitive behavioral approach are promising, and primarily indirect evidence indicates that it applies also when they are delivered with a reduced number of therapist contacts or remotely.

Systematic review registration: 01KG1012 at http://www.gesundheitsforschung-bmbf.de/de/2852.php

Electronic supplementary material

The online version of this article (doi:10.1186/s12875-015-0314-x) contains supplementary material, which is available to authorized users.

Comparative effectiveness and tolerance of treatments for Helicobacter pylori: systematic review and network meta-analysis

OBJECTIVE

To determine the most efficacious treatment for eradication of Helicobacter pylori with the lowest likelihood of some common adverse events among pre-recommended and newer treatment regimens.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Cochrane Library, PubMed, and Embase without language or date restrictions.

STUDY SELECTION

Full text reports of randomised controlled trials that compared different eradication treatments for H pylori among adults.

RESULTS

Of the 15,565 studies identified, 143 were eligible and included. Data on 14 kinds of treatments were available. Of 91 possible comparisons for the efficacy outcome, 34 were compared directly and the following treatments performed better: seven days of concomitant treatment (proton pump inhibitor and three kinds of antibiotics administered together), 10 or 14 days of concomitant treatment, 10 or 14 days of probiotic supplemented triple treatment (standard triple treatment which is probiotic supplemented), 10 or 14 days of levofloxacin based triple treatment (proton pump inhibitor, levofloxacin, and antibiotic administered together), 14 days of hybrid treatment (proton pump inhibitor and amoxicillin used for seven days, followed by a proton pump inhibitor, amoxicillin, clarithromycin, and 5-nitroimidazole for another seven days), and 10 or 14 days of sequential treatment (five or seven days of a proton pump inhibitor plus amoxicillin, followed by five or seven additional days of a proton pump inhibitor plus clarithromycin and 5-nitroimidazole or amoxicillin). In terms of tolerance, all treatments were considered tolerable, but seven days of probiotic supplemented triple treatment and seven days of levofloxacin based triple treatment ranked best in terms of the proportion of adverse events reported.

CONCLUSION

Comparison of different eradication treatments for H pylori showed that concomitant treatments, 10 or 14 days of probiotic supplemented triple treatment, 10 or 14 days of levofloxacin based triple treatment, 14 days of hybrid treatment, and 10 or 14 days of sequential treatment might be better alternatives for the eradication of H pylori.

Comparative efficacy of antibiotics for the treatment of acute bacterial skin and skin structure infections (ABSSSI): a systematic review and network meta-analysis

OBJECTIVE

The objective was to conduct a systematic review and network meta-analysis (NMA) of existing treatments for ABSSSI focusing on the novel lipoglycopeptide oritavancin.

METHODS

EMBASE, MEDLINE, MEDLINE in Process, CENTRAL (Cochrane), and select conferences were searched for randomized controlled trials investigating antimicrobial agents for the treatment of ABSSSI. NMA was used to estimate the odds ratios of the Test-Of-Cure (TOC) and Early Clinical Response (ECR) outcomes for treatments relative to vancomycin in the ITT populations. Sub-group analyses in MRSA and MSSA populations were conducted for TOC; sensitivity analyses investigated the use of the clinically evaluable (CE) populations and the restriction to trials following the recent FDA guidelines for clinical trials.

RESULTS

The systematic review identified 52 trials. The most commonly investigated treatments were vancomycin and linezolid; most trials reported TOC, but not ECR. The posterior mean and 95% credible intervals for odds ratios of TOC for antimicrobial agents relative to vancomycin were: linezolid (1.55; 0.91-2.57), daptomycin (2.18; 0.90-5.42), and oritavancin 1200 mg (1.06; 0.80-1.43). The odds ratio of ECR for oritavancin 1200 mg was 1.02 (0.23-4.33). In the MRSA sub-group the odds ratios relative to vancomycin for TOC were: linezolid (1.55; 0.96-2.46), daptomycin (0.74; 0.13-3.66), and oritavancin 1200 mg (0.94; 0.44-2.02). In the MSSA sub-group they were linezolid (1.36; 0.15-13.34) and oritavancin 1200 mg (0.82; 0.08-7.83). These results were robust to the sensitivity analyses.

CONCLUSIONS

This NMA provides a unified framework for the comparison of all available antimicrobial agents used in the treatment of ABSSSI and is the first to assess the ECR end-point. The results suggest equivalence of clinical efficacy between vancomycin, daptomycin, linezolid, and novel antimicrobial agents including oritavancin for the treatment of ABSSSI at TOC. The wide uncertainty margins indicate the heterogeneity of the available evidence and the need for further research.

Comparative Effectiveness and Safety of Monodrug Therapies for Lower Urinary Tract Symptoms Associated With Benign Prostatic Hyperplasia: A Network Meta-analysis

A wide array of drugs are available for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH), but the evidence for the comparative effectiveness is controversial.The objective of this study is to evaluate the comparative effectiveness and safety of monodrug therapies for BPH.Data sources are MEDLINE, EMBASE, and the Cochrane Library.We included randomized controlled trials that compared α-blockers, 5-alpha reductase inhibitors (5ARIs), muscarinic receptor antagonists (MRAs), phosphodiesterase-5 inhibitor (PDE5-Is), or placebo for the treatment of BPH.Comparative effectiveness and safety were pooled by both traditional meta-analysis and network meta-analysis. Summary effect size was calculated as mean difference (MD) and relative risk (RR), together with the 95% confidence intervals (CIs).This study included 58,548 participants from 124 trials in total. When compared with placebo, α-blockers, 5ARIs, and PDE5-Is reduced International Prostate Symptom Score (IPSS) by -1.35 to -3.67 points and increased peak urinary flow rate (PUF) by -0.02 to 1.95 mL/s, with doxazosin (IPSS: MD, -3.67[-4.33 to -3.02]; PUF: MD, 1.95[1.61 to 2.30]) and terazosin (IPSS: MD, -3.37 [-4.24 to -2.50]; PUF: MD, 1.21[0.74 to 1.66]) showing the greatest improvement. The improvement in the IPSS was comparable among tamsulosin, alfuzosin, naftopidil, silodosin, dutasteride, sildenafil, vardenafil, and tadalafil. The incidence of total adverse events and withdraws due to adverse events were generally comparable among various agents.In conclusion, α-blockers, 5ARIs, and PDE5-Is are effective for BPH, with doxazosin and terazosin appearing to be the most effective agents. Drug therapies for BPH are generally safe and well-tolerated, with no major difference regarding the overall safety profile.