Prognostic tools for identification of high risk in people with Crohn's disease: systematic review and cost-effectiveness study.

BACKGROUND: Crohn's disease is a lifelong condition that can affect any segment of the gastrointestinal tract. Some people with Crohn's disease may be at higher risk of following a severe course of disease than others and being able to identify the level of risk a patient has could lead to personalised management. OBJECTIVE: To assess the prognostic test accuracy, clinical impact and cost-effectiveness of two tools for the stratification of people with a diagnosis of Crohn's disease by risk of following a severe course of disease. DATA SOURCES: The data sources MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews and the Cochrane Central Register of Controlled Trials were searched to inform the systematic reviews on prognostic accuracy, clinical impact of the prognostic tools, and economic evaluations. Additional data sources to inform the review of economic evaluations were NHS Economic Evaluation Database, Database of Abstracts of Reviews of Effects and the Health Technology Assessment Database. REVIEW METHODS: Systematic reviews of electronic databases were carried out from inception to June 2019 for studies assessing the prognostic accuracy and clinical impact of the IBDX® (Crohn's disease Prognosis Test; Glycominds Ltd, Lod, Israel) biomarker stratification tool and the PredictSURE-IBD™ (PredictImmune Ltd, Cambridge, UK) tool. Systematic reviews of studies reporting on the cost-effectiveness of treatments for Crohn's disease were run from inception to July 2019. Two reviewers independently agreed on studies for inclusion, assessed the quality of included studies and validated the data extracted from studies. Clinical and methodological heterogeneity across studies precluded the synthesis of data for prognostic accuracy. A de novo economic model was developed to compare the costs and consequences of two treatment approaches - the 'top-down' and 'step-up' strategies, with step-up considered standard care - in people at high risk of following a severe course of Crohn's disease. The model comprised a decision tree and a Markov cohort model. RESULTS: Sixteen publications, including eight original studies (n = 1478), were deemed relevant to the review of prognostic accuracy. Documents supplied by the companies marketing the prognostic tools were also reviewed. No study meeting the eligibility criteria reported on the sensitivity or specificity of the IBDX biomarker stratification tool, whereas one study provided estimates of sensitivity, specificity and negative predictive value for the PredictSURE-IBD tool. All identified studies were observational and were considered to provide weak evidence on the effectiveness of the tools. Owing to the paucity of data on the two tools, in the base-case analysis the accuracy of PredictSURE-IBD was assumed to be 100%. Accuracy of IBDX was assumed to be 100% in a scenario analysis, with the cost of the tests being the only difference between the analyses. The incremental analysis of cost-effectiveness demonstrated that top-down (via the use of PredictSURE-IBD in the model) is more expensive and generates fewer quality-adjusted life-years than step-up (via the standard care arm of the model). LIMITATIONS: Despite extensive systematic searches of the literature, no robust evidence was identified of the prognostic accuracy of the biomarker stratification tools IBDX and PredictSURE-IBD. CONCLUSIONS: Although the model indicates that standard care dominates the tests, the lack of evidence of prognostic accuracy of the two tests and the uncertainty around the benefits of the top-down and step-up treatment approaches mean that the results should be interpreted as indicative rather than definitive. STUDY REGISTRATION: This study is registered as PROSPERO CRD42019138737. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 23. See the NIHR Journals Library website for further project information.

Crohn's disease is a condition in which parts of the digestive system become inflamed (swollen). People of any age can develop Crohn's disease. It is a lifelong condition for which there is no cure. In the UK, Crohn's disease affects about 1 in every 650 people. Any part of the digestive system can be affected, and the severity of the disease can vary from person to person. Symptoms come and go, and there can be times when there are no symptoms at all. Common symptoms of Crohn's disease are diarrhoea, stomach-ache and blood in faeces. Treatment is given to reduce or control symptoms and to try to stop inflammation from coming back. Some people with Crohn's disease are more likely than others to have more relapses and to develop complications of Crohn's disease that might require surgery. This project looked at how well two tools worked at identifying people with Crohn's disease who might develop complications or need surgery. Identifying those who have a higher chance of experiencing complications of Crohn's disease could help them and their doctor to choose their treatment, with the goal of reducing the number of relapses and the risk of surgery in the longer term. In addition, the review assessed whether or not the tools offered value for money. We found limited evidence of how well the tools worked in identifying people who were more likely to develop complications of Crohn's disease. The lack of evidence on the tools meant that the cost-effectiveness analysis could only assess the value for money of the treatment that is given in clinical practice at this time or of more intensive treatments for people who are more likely to develop complications. The analysis found that current standard care offers more value for money than intensive treatments for people with a higher chance of developing complications of Crohn's disease.

Implantable cardiac monitors to detect atrial fibrillation after cryptogenic stroke: a systematic review and economic evaluation.

BACKGROUND: Cryptogenic stroke is a stroke for which no cause is identified after standard diagnostic tests. Long-term implantable cardiac monitors may be better at diagnosing atrial fibrillation and provide an opportunity to reduce the risk of stroke recurrence with anticoagulants. OBJECTIVES: The objectives were to assess the diagnostic test accuracy, clinical effectiveness and cost-effectiveness of three implantable monitors [BioMonitor 2-AF™ (Biotronik SE & Co. KG, Berlin, Germany), Confirm Rx™ (Abbott Laboratories, Lake Bluff, IL, USA) and Reveal LINQ™ (Medtronic plc, Minneapolis, MN, USA)] in patients who have had a cryptogenic stroke and for whom no atrial fibrillation is detected after 24 hours of external electrocardiographic monitoring. DATA SOURCES: MEDLINE, EMBASE, The Cochrane Library, Database of Abstracts of Reviews of Effects and Health Technology Assessment databases were searched from inception until September 2018. REVIEW METHODS: A systematic review was undertaken. Two reviewers agreed on studies for inclusion and performed quality assessment using the Cochrane Risk of Bias 2.0 tool. Results were discussed narratively because there were insufficient data for synthesis. A two-stage de novo economic model was developed: (1) a short-term patient flow model to identify cryptogenic stroke patients who have had atrial fibrillation detected and been prescribed anticoagulation treatment (rather than remaining on antiplatelet treatment) and (2) a long-term Markov model that captured the lifetime costs and benefits of patients on either anticoagulation or antiplatelet treatment. RESULTS: One randomised controlled trial, Cryptogenic Stroke and underlying Atrial Fibrillation (CRYSTAL-AF) (Sanna T, Diener HC, Passman RS, Di Lazzaro V, Bernstein RA, Morillo CA, et al. Cryptogenic stroke and underlying atrial fibrillation. N Engl J Med 2014;370:2478-86), was identified, and no diagnostic test accuracy study was identified. The CRYSTAL-AF trial compared the Reveal™ XT (a Reveal LINQ predecessor) (Medtronic plc) monitor with standard of care monitoring. Twenty-six single-arm observational studies for the Reveal devices were also identified. The only data for BioMonitor 2-AF or Confirm Rx were from mixed population studies supplied by the companies. Atrial fibrillation detection in the CRYSTAL-AF trial was higher with the Reveal XT than with standard monitoring at all time points. By 36 months, atrial fibrillation was detected in 19% of patients with an implantable cardiac monitor and in 2.3% of patients receiving conventional follow-up. The 26 observational studies demonstrated that, even in a cryptogenic stroke population, atrial fibrillation detection rates are highly variable and most cases are asymptomatic; therefore, they probably would not have been picked up without an implantable cardiac monitor. Device-related adverse events, such as pain and infection, were low in all studies. The de novo economic model produced incremental cost effectiveness ratios comparing implantable cardiac monitors with standard of care monitoring to detect atrial fibrillation in cryptogenic stroke patients based on data for the Reveal XT device, which can be related to Reveal LINQ. The BioMonitor 2-AF and Confirm RX were included in the analysis by making a strong assumption of equivalence with Reveal LINQ. The results indicate that implantable cardiac monitors could be considered cost-effective at a £20,000-30,000 threshold. When each device is compared incrementally, BioMonitor 2-AF dominates Reveal LINQ and Confirm RX. LIMITATIONS: The cost-effectiveness analysis for implantable cardiac monitors is based on a strong assumption of clinical equivalence and should be interpreted with caution. CONCLUSIONS: All three implantable cardiac monitors could be considered cost-effective at a £20,000-30,000 threshold, compared with standard of care monitoring, for cryptogenic stroke patients with no atrial fibrillation detected after 24 hours of external electrocardiographic monitoring; however, further clinical studies are required to confirm their efficacy in cryptogenic stroke patients. STUDY REGISTRATION: This study is registered as PROSPERO CRD42018109216. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 5. See the NIHR Journals Library website for further project information.

An abnormal heart rhythm (atrial fibrillation) is an important cause of stroke. Clots form in the heart, break off, pass into blood vessels in the head and block the blood supply to parts of the brain. This is important to diagnose because atrial fibrillation can be treated with blood-thinning drugs, which can prevent further stroke. For this reason, all patients with stroke are tested for atrial fibrillation. Unfortunately, the standard tests, which include 24 hours of outpatient external heart monitoring, may miss the condition. Implantable cardiac monitors, which are small devices placed beneath the skin of the chest that can monitor the heart for up to 4 years, may be better than the standard tests. This study compared three different implantable cardiac monitors [BioMonitor 2-AF™ (Biotronik SE & Co. KG, Berlin, Germany), Confirm Rx™ (Abbott Laboratories, Lake Bluff, IL, USA) and Reveal LINQ™ (Medtronic plc, Minneapolis, MN, USA)] to determine how effective they are at detecting atrial fibrillation in people who have had a cryptogenic stroke (a stroke for which no cause is identified), whether or not they are better than standard monitoring and whether or not they offer good value for money. No evidence was found that directly compared the three implantable monitors in cryptogenic stroke patients. The limited evidence found suggested that all three monitors had few side effects; only one monitor (Reveal LINQ) had evidence that it was better than standard monitoring. By 36 months, 19% of patients had atrial fibrillation detected by Reveal LINQ compared with only 2.3% with conventional monitoring. There was insufficient information for the other monitors. Overall, implantable monitors offer value for money when compared with standard monitoring for people who have had a cryptogenic stroke and for whom atrial fibrillation has not been detected with standard tests.

Effectiveness of topical and ablative therapies in treatment of anogenital warts: a systematic review and network meta-analysis.

OBJECTIVE: To generate estimates of comparative clinical effectiveness for interventions used in the treatment of anogenital warts (AGWs) through the systematic review, appraisal and synthesis of data from randomised controlled trials (RCTs). DESIGN: Systematic review and network meta-analysis of RCTs. Search strategies were developed for MEDLINE, Embase, the Cochrane Library and the Web of Science. For electronic databases, searches were run from inception to March 2018. The systematic review was carried out following the general principles recommended in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PARTICIPANTS: People aged ≥16 years with clinically diagnosed AGWs (irrespective of biopsy confirmation). INTERVENTIONS: Topical and ablative treatments recommended by the British Association for Sexual Health and HIV for the treatment of AGWs, either as monotherapy or in combination versus each other. OUTCOME MEASURES: Complete clearance of AGWs at the end of treatment and at other scheduled visits, and rate of recurrence. RESULTS: Thirty-seven RCTs met inclusion criteria. Twenty studies were assessed as being at unclear risk of bias, with the remaining studies categorised as high risk of bias. Network meta-analysis indicates that, of the treatment options compared, carbon dioxide laser therapy is the most effective treatment for achieving complete clearance of AGWs at the end of treatment. Of patient-applied topical treatments, podophyllotoxin 0.5% solution was found to be the most effective at achieving complete clearance, and was associated with a statistically significant difference compared with imiquimod 5% cream and polyphenon E 10% ointment (p<0.05). Few data were available on recurrence of AGWs after complete clearance. Of the interventions evaluated, surgical excision was the most effective at minimising risk of recurrence. CONCLUSION: Of the studies assessed, as a collective, the quality of the evidence is low. Few studies are available that evaluate treatment options versus each other. TRIAL REGISTRATION NUMBER: CRD42013005457.

Targeted therapies for previously treated advanced or metastatic renal cell carcinoma: systematic review and network meta-analysis.

OBJECTIVE: To compare the effectiveness and safety of treatments for advanced or metastatic renal cell carcinoma (amRCC) after treatment with vascular endothelial growth factor (VEGF)-targeted treatment. DESIGN: Systematic review and network meta-analysis of randomised controlled trials (RCTs) and comparative observational studies. MEDLINE, EMBASE and Cochrane Library were searched up to January 2018. PARTICIPANTS: People with amRCC requiring treatment after VEGF-targeted treatment. INTERVENTIONS: Axitinib, cabozantinib, everolimus, lenvatinib with everolimus, nivolumab, sorafenib and best supportive care (BSC). OUTCOMES: Primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes were objective response rate (ORR), adverse events, and health-related quality of life (HRQoL). RESULTS: Twelve studies were included (n=5144): five RCTs and seven observational studies. Lenvatinib with everolimus significantly increased OS and PFS over everolimus (HR 0.61, 95% Credible Interval [95%CrI]: 0.36 to 0.96 and 0.47, 95%CrI: 0.26 to 0.77, respectively) as did cabozantinib (HR 0.66, 95%CrI: 0.53 to 0.82 and 0.51, 95%CrI: 0.41 to 0.63, respectively). This remained the case when observational evidence was included. Nivolumab also significantly improved OS versus everolimus (HR 0.74, 95%CrI: 0.57 to 0.93). OS sensitivity analysis, including observational studies, indicates everolimus being more effective than axitinib and sorafenib. However, inconsistency was identified in the OS sensitivity analysis. PFS sensitivity analysis suggests axitinib is more effective than everolimus, which may be more effective than sorafenib. The results for ORR supported the OS and PFS analyses. Nivolumab is associated with fewer grade 3 or grade 4 adverse events than lenvatinib with everolimus or cabozantinib. HRQoL could not be analysed due to differences in tools used. CONCLUSIONS: Lenvatinib with everolimus, cabozantinib and nivolumab are effective in prolonging the survival for people with amRCC subsequent to VEGF-targeted treatment, but there is considerable uncertainty about how they compare to each other and how much better they are than axitinib and sorafenib. PROSPERO REGISTRATION NUMBER: CRD42017071540.

Axitinib, cabozantinib, everolimus, nivolumab, sunitinib and best supportive care in previously treated renal cell carcinoma: a systematic review and economic evaluation.

BACKGROUND: Several therapies have recently been approved for use in the NHS for pretreated advanced or metastatic renal cell carcinoma (amRCC), but there is a lack of comparative evidence to guide decisions between them. OBJECTIVE: To evaluate the clinical effectiveness and cost-effectiveness of axitinib (Inlyta®, Pfizer Inc., NY, USA), cabozantinib (Cabometyx®, Ipsen, Slough, UK), everolimus (Afinitor®, Novartis, Basel, Switzerland), nivolumab (Opdivo®, Bristol-Myers Squibb, NY, USA), sunitinib (Sutent®, Pfizer, Inc., NY, USA) and best supportive care (BSC) for people with amRCC who were previously treated with vascular endothelial growth factor (VEGF)-targeted therapy. DATA SOURCES: A systematic review and mixed-treatment comparison (MTC) of randomised controlled trials (RCTs) and non-RCTs. Primary outcomes were overall survival (OS) and progression-free survival (PFS). Secondary outcomes were objective response rates (ORRs), adverse events (AEs) and health-related quality of life (HRQoL). MEDLINE, EMBASE and The Cochrane Library were searched from inception to January and June 2016 for RCTs and non-RCTs, respectively. Two reviewers abstracted data and performed critical appraisals. REVIEW METHODS: A fixed-effects MTC was conducted for OS, PFS [hazard ratios (HRs)] and ORR (odds ratios), and all were presented with 95% credible intervals (CrIs). The RCT data formed the primary analyses, with non-RCTs and studies rated as being at a high risk of bias included in sensitivity analyses (SAs). HRQoL and AE data were summarised narratively. A partitioned survival model with health states for pre progression, post progression and death was developed to perform a cost-utility analysis. Survival curves were fitted to the PFS and OS results from the MTC. A systematic review of HRQoL was undertaken to identify sources of health state utility values. RESULTS: Four RCTs (n = 2618) and eight non-RCTs (n = 1526) were included. The results show that cabozantinib has longer PFS than everolimus (HR 0.51, 95% CrI 0.41 to 0.63) and both treatments are better than BSC. Both cabozantinib (HR 0.66, 95% CrI 0.53 to 0.82) and nivolumab (HR 0.73, 95% CrI 0.60 to 0.89) have longer OS than everolimus. SAs were consistent with the primary analyses. The economic analysis, using drug list prices, shows that everolimus may be more cost-effective than BSC with an incremental cost-effectiveness ratio (ICER) of £45,000 per quality-adjusted life-year (QALY), as it is likely to be considered an end-of-life treatment. Cabozantinib has an ICER of £126,000 per QALY compared with everolimus and is unlikely to be cost-effective. Nivolumab was dominated by cabozantinib (i.e. more costly and less effective) and axitinib was dominated by everolimus. LIMITATIONS: Treatment comparisons were limited by the small number of RCTs. However, the key limitation of the analysis is the absence of the drug prices paid by the NHS, which was a limitation that could not be avoided owing to the confidentiality of discounts given to the NHS. CONCLUSIONS: The RCT evidence suggests that cabozantinib is likely to be the most effective for PFS and OS, closely followed by nivolumab. All treatments appear to delay disease progression and prolong survival compared with BSC, although the results are heterogeneous. The economic analysis shows that at list price everolimus could be recommended as the other drugs are much more expensive with insufficient incremental benefit. The applicability of these findings to the NHS is somewhat limited because existing confidential patient access schemes could not be used in the analysis. Future work using the discounted prices at which these drugs are provided to the NHS would better inform estimates of their relative cost-effectiveness. STUDY REGISTRATION: This study is registered as PROSPERO CRD42016042384. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

VivaScope® 1500 and 3000 systems for detecting and monitoring skin lesions: a systematic review and economic evaluation.

BACKGROUND: Skin cancer is one of the most common cancers in the UK. The main risk factor is exposure to ultraviolet radiation from sunlight or the use of sunbeds. Patients with suspicious skin lesions are first examined with a dermoscope. After examination, those with non-cancerous lesions are discharged, but lesions that are still considered clinically suspicious are surgically removed. VivaScope(®) is a non-invasive technology designed to be used in conjunction with dermoscopy to provide a more accurate diagnosis, leading to fewer biopsies of benign lesions or to provide more accurate presurgical margins reducing the risk of cancer recurrence. OBJECTIVES: To evaluate the clinical effectiveness and cost-effectiveness of VivaScope(®) 1500 (Caliber Imaging and Diagnostics, Rochester, NY, USA; Lucid Inc., Rochester, NY, USA; or Lucid Inc., MAVIG GmbH, Munich, Germany) and VivaScope(®) 3000 (Caliber Imaging and Diagnostics, Rochester, NY, USA) in the diagnosis of equivocal skin lesions, and VivaScope 3000 in lesion margin delineation prior to surgical excision of lesions. DATA SOURCES: Databases (MEDLINE, EMBASE and The Cochrane Library) were searched on 14 October 2014, reference lists of included papers were assessed and clinical experts were contacted for additional information on published and unpublished studies. METHODS: A systematic review was carried out to identify randomised controlled trials (RCTs) or observational studies evaluating dermoscopy plus VivaScope, or VivaScope alone, with histopathology as the reference test. A probabilistic de novo economic model was developed to synthesise the available data on costs and clinical outcomes from the UK NHS perspective. All costs were expressed as 2014 prices. RESULTS: Sixteen studies were included in the review, but they were too heterogeneous to be combined in a meta-analysis. One of two diagnostic studies that were deemed most representative of UK clinical practice reported that dermoscopy plus VivaScope 1500 was significantly more sensitive than dermoscopy alone in the diagnosis of melanoma (97.8% vs. 94.6%; p = 0.043) and significantly more specific than dermoscopy alone in the diagnosis of non-melanoma (92.4% vs. 26.74%; p < 0.000001). The results of another study suggest 100% [95% confidence interval (CI) 86.16% to 100%] sensitivity for dermoscopy plus VivaScope 1500 versus 100% (95% CI 91.51% to 100%) for dermoscopy alone. Specificity varied from 51.77% to 80.2% depending on the analysis set used. In terms of margin delineation with VivaScope, one study found that 17 out of 29 patients with visible lentigo maligna (LM) had subclinical disease of > 5 mm beyond the dermoscopically identified margin. Using 'optimistic' diagnostic data, the economic model resulted in an incremental cost-effectiveness ratio (ICER) of £8877 per quality-adjusted life-year (QALY) (£9362 per QALY), while the 'less favourable' diagnostic data resulted in an ICER of £19,095 per QALY (£25,453 per QALY) in the diagnosis of suspected melanomas. VivaScope was also shown to be a dominant strategy when used for the diagnostic assessment of suspected basal cell carcinoma (BCC). Regarding margin delineation of LM, mapping with VivaScope was cost-effective, with an ICER of £10,241 per QALY (£11,651 per QALY). However, when VivaScope was used for diagnosis as well as mapping of LM, then the intervention cost was reduced and VivaScope became a dominant strategy. LIMITATIONS: There is an absence of UK data in the included studies and, therefore, generalisability of the results to the UK population is unclear. CONCLUSIONS: The use of VivaScope appears to be a cost-effective strategy in the diagnostic assessment of equivocal melanomas and BCCs, and in margin delineation of LM prior to surgical treatment. FUTURE WORK: High-quality RCTs are required in a UK population to assess the diagnostic accuracy of VivaScope in people with equivocal lesions. STUDY REGISTRATION: This study is registered as PROSPERO CRD42014014433. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

The use of fibrin sealant during non-emergency surgery: a systematic review of evidence of benefits and harms.

BACKGROUND: Fibrin sealants are used in different types of surgery to prevent the accumulation of post-operative fluid (seroma) or blood (haematoma) or to arrest haemorrhage (bleeding). However, there is uncertainty around the benefits and harms of fibrin sealant use. OBJECTIVES: To systematically review the evidence on the benefits and harms of fibrin sealants in non-emergency surgery in adults. DATA SOURCES: Electronic databases [MEDLINE, EMBASE and The Cochrane Library (including the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Health Technology Assessment database and the Cochrane Central Register of Controlled Trials)] were searched from inception to May 2015. The websites of regulatory bodies (the Medicines and Healthcare products Regulatory Agency, the European Medicines Agency and the Food and Drug Administration) were also searched to identify evidence of harms. REVIEW METHODS: This review included randomised controlled trials (RCTs) and observational studies using any type of fibrin sealant compared with standard care in non-emergency surgery in adults. The primary outcome was risk of developing seroma and haematoma. Only RCTs were used to inform clinical effectiveness and both RCTs and observational studies were used for the assessment of harms related to the use of fibrin sealant. Two reviewers independently screened all titles and abstracts to identify potentially relevant studies. Data extraction was undertaken by one reviewer and validated by a second. The quality of included studies was assessed independently by two reviewers using the Cochrane Collaboration risk-of-bias tool for RCTs and the Centre for Reviews and Dissemination guidance for adverse events for observational studies. A fixed-effects model was used for meta-analysis. RESULTS: We included 186 RCTs and eight observational studies across 14 surgical specialties and five reports from the regulatory bodies. Most RCTs were judged to be at an unclear risk of bias. Adverse events were inappropriately reported in observational studies. Meta-analysis across non-emergency surgical specialties did not show a statistically significant difference in the risk of seroma for fibrin sealants versus standard care in 32 RCTs analysed [n = 3472, odds ratio (OR) 0.84, 95% confidence interval (CI) 0.68 to 1.04; p = 0.13; I2 = 12.7%], but a statistically significant benefit was found on haematoma development in 24 RCTs (n = 2403, OR 0.62, 95% CI 0.44 to 0.86; p = 0.01; I2 = 0%). Adverse events related to fibrin sealant use were reported in 10 RCTs and eight observational studies across surgical specialties, and 22 RCTs explicitly stated that there were no adverse events. One RCT reported a single death but no other study reported mortality or any serious adverse events. Five regulatory body reports noted death from air emboli associated with fibrin sprays. LIMITATIONS: It was not possible to provide a detailed evaluation of individual RCTs in their specific contexts because of the limited resources that were available for this research. In addition, the number of RCTs that were identified made it impractical to conduct independent data extraction by two reviewers in the time available. CONCLUSIONS: The effectiveness of fibrin sealants does not appear to vary according to surgical procedures with regard to reducing the risk of seroma or haematoma. Surgeons should note the potential risk of gas embolism if spray application of fibrin sealants is used and not to exceed the recommended pressure and spraying distance. Future research should be carried out in surgery specialties for which only limited data were found, including neurological, gynaecological, oral and maxillofacial, urology, colorectal and orthopaedics surgery (for any outcome); breast surgery and upper gastrointestinal (development of haematoma); and cardiothoracic heart or lung surgery (reoperation rates). In addition, studies need to use adequate sample sizes, to blind participants and outcome assessors, and to follow reporting guidelines. STUDY REGISTRATION: This study is registered as PROSPERO CRD42015020710. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Dual-chamber pacemakers for treating symptomatic bradycardia due to sick sinus syndrome without atrioventricular block: a systematic review and economic evaluation.

BACKGROUND: Bradycardia [resting heart rate below 60 beats per minute (b.p.m.)] can be caused by conditions affecting the natural pacemakers of the heart, such as sick sinus syndrome (SSS) and atrioventricular (AV) blocks. People suffering from bradycardia may present with palpitations, exercise intolerance and fainting. The only effective treatment for patients suffering from symptomatic bradycardia is implantation of a permanent pacemaker. OBJECTIVE: To appraise the clinical effectiveness and cost-effectiveness of dual-chamber pacemakers compared with single-chamber atrial pacemakers for treating symptomatic bradycardia in people with SSS and no evidence of AV block. DATA SOURCES: All databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Health Technology Assessment database, NHS Economic Evaluations Database) were searched from inception to June 2014. METHODS: A systematic review of the clinical and economic literature was carried out in accordance with the general principles published by the Centre for Reviews and Dissemination. Randomised controlled trials (RCTs) evaluating dual-chamber and single-chamber atrial pacemakers and economic evaluations were included. Pairwise meta-analysis was carried out. A de novo economic model was developed. RESULTS: Of 493 references, six RCTs were included in the review. The results were predominantly influenced by the largest trial DANPACE. Dual-chamber pacing was associated with a statistically significant reduction in reoperation [odds ratio (OR) 0.48, 95% confidence interval (CI) 0.36 to 0.63] compared with single-chamber atrial pacing. The difference is primarily because of the development of AV block requiring upgrade to a dual-chamber device. The risk of paroxysmal atrial fibrillation was also reduced with dual-chamber pacing compared with single-chamber atrial pacing (OR 0.75, 95% CI 0.59 to 0.96). No statistically significant difference was found between the pacing modes for mortality, heart failure, stroke, chronic atrial fibrillation or quality of life. However, the risk of developing heart failure may vary with age and device. The de novo economic model shows that dual-chamber pacemakers are more expensive and more effective than single-chamber atrial devices, resulting in a base-case incremental cost-effectiveness ratio (ICER) of £6506. The ICER remains below £20,000 in probabilistic sensitivity analysis, structural sensitivity analysis and most scenario analyses and one-way sensitivity analyses. The risk of heart failure may have an impact on the decision to use dual-chamber or single-chamber atrial pacemakers. Results from an analysis based on age (> 75 years or ≤ 75 years) and risk of heart failure indicate that dual-chamber pacemakers dominate single-chamber atrial pacemakers (i.e. are less expensive and more effective) in older patients, whereas dual-chamber pacemakers are dominated by (i.e. more expensive and less effective) single-chamber atrial pacemakers in younger patients. However, these results are based on a subgroup analysis and should be treated with caution. CONCLUSIONS: In patients with SSS without evidence of impaired AV conduction, dual-chamber pacemakers appear to be cost-effective compared with single-chamber atrial pacemakers. The risk of developing a complete AV block and the lack of tools to identify patients at high risk of developing the condition argue for the implantation of a dual-chamber pacemaker programmed to minimise unnecessary ventricular pacing. However, considerations have to be made around the risk of developing heart failure, which may depend on age and device. STUDY REGISTRATION: This study is registered as PROSPERO CRD42013006708. FUNDING: The National Institute for Health Research Health Technology Assessment programme.