Matthew Glover

Systematic review and meta-analysis of the growth and rupture rates of small abdominal aortic aneurysms: implications for surveillance intervals and their cost-effectiveness

BACKGROUND Small abdominal aortic aneurysms (AAAs; 3.0-5.4 cm in diameter) are usually asymptomatic and managed by regular ultrasound surveillance until they grow to a diameter threshold (commonly 5.5 cm) at which surgical intervention is considered. The choice of appropriate surveillance intervals is governed by the growth and rupture rates of small AAAs, as well as their relative cost-effectiveness. OBJECTIVES The aim of this series of studies was to inform the evidence base for small AAA surveillance strategies. This was achieved by literature review, collation and analysis of individual patient data, a focus group and health economic modelling. DATA SOURCES We undertook systematic literature reviews of growth rates and rupture rates of small AAAs. The databases MEDLINE, EMBASE on OvidSP, Cochrane Central Register of Controlled Trials 2009 Issue 4, ClinicalTrials.gov, and controlled-trials.com were searched from inception up until the end of 2009. We also obtained individual data on 15,475 patients from 18 surveillance studies. REVIEW METHODS Systematic reviews of publications identified 15 studies providing small AAA growth rates, and 14 studies with small AAA rupture rates, up to December 2009 (later updated to September 2012). We developed statistical methods to analyse individual surveillance data, including the effects of patient characteristics, to inform the choice of surveillance intervals and provide inputs for health economic modelling. We updated an existing health economic model of AAA screening to address the cost-effectiveness of different surveillance intervals. RESULTS In the literature reviews, the mean growth rate was 2.3 mm/year and the reported rupture rates varied between 0 and 1.6 ruptures per 100 person-years. Growth rates increased markedly with aneurysm diameter, but insufficient detail was available to guide surveillance intervals. Based on individual surveillance data, for each 0.5-cm increase in AAA diameter, growth rates increased by about 0.5 mm/year and rupture rates doubled. To control the risk of exceeding 5.5 cm to below 10% in men, on average a 7-year surveillance interval is sufficient for a 3.0-cm aneurysm, whereas an 8-month interval is necessary for a 5.0-cm aneurysm. To control the risk of rupture to below 1%, the corresponding estimated surveillance intervals are 9 years and 17 months. Average growth rates were higher in smokers (by 0.35 mm/year) and lower in patients with diabetes (by 0.51 mm/year). Rupture rates were almost fourfold higher in women than men, doubled in current smokers and increased with higher blood pressure. Increasing the surveillance interval from 1 to 2 years for the smallest aneurysms (3.0-4.4 cm) decreased costs and led to a positive net benefit. For the larger aneurysms (4.5-5.4 cm), increasing surveillance intervals from 3 to 6 months led to equivalent cost-effectiveness. LIMITATIONS There were no clear reasons why the growth rates varied substantially between studies. Uniform diagnostic criteria for rupture were not available. The long-term cost-effectiveness results may be susceptible to the modelling assumptions made. CONCLUSIONS Surveillance intervals of several years are clinically acceptable for men with AAAs in the range 3.0-4.0 cm. Intervals of around 1 year are suitable for 4.0-4.9-cm AAAs, whereas intervals of 6 months would be acceptable for 5.0-5.4-cm AAAs. These intervals are longer than those currently employed in the UK AAA screening programmes. Lengthening surveillance intervals for the smallest aneurysms was also shown to be cost-effective. Future work should focus on optimising surveillance intervals for women, studying whether or not the threshold for surgery should depend on patient characteristics, evaluating the usefulness of surveillance for those with aortic diameters of 2.5-2.9 cm, and developing interventions that may reduce the growth or rupture rates of small AAAs. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Meta-analysis of randomised controlled trials of oral mandibular advancement devices and continuous positive airway pressure for obstructive sleep apnoea-hypopnoea.

Summary Obstructive sleep apnoea-hypopnoea (OSAH) causes excessive daytime sleepiness, impairs quality-of-life, and increases cardiovascular disease and road traffic accident risks. Continuous positive airway pressure (CPAP) treatment and mandibular advancement devices (MAD) have been shown to be effective in individual trials but their effectiveness particularly relative to disease severity is unclear. A MEDLINE, Embase and Science Citation Index search updating two systematic reviews to August 2013 identified 77 RCTs in adult OSAH patients comparing: MAD with conservative management (CM); MAD with CPAP; or CPAP with CM. Overall MAD and CPAP significantly improved apnoea-hypopnoea index (AHI) (MAD −9.3/hr (p < 0.001), CPAP −25.4 (p < 0.001)). In direct comparisons mean AHI and Epworth sleepiness scale score were lower (7.0/hr (p < 0.001) and 0.67 (p = 0.093) respectively) for CPAP. There were no CPAP vs. MAD trials in mild OSAH but in comparisons with CM, MAD and CPAP reduced ESS similarly (MAD 2.01 (p < 0.001); CPAP 1.23 (p = 0.012). Both MAD and CPAP are clinically effective in the treatment of OSAH. Although CPAP has a greater treatment effect, MAD is an appropriate treatment for patients who are intolerant of CPAP and may be comparable to CPAP in mild disease.

Cost-effectiveness of the National Health Service abdominal aortic aneurysm screening programme in England

Implementation of the National Health Service abdominal aortic aneurysm (AAA) screening programme (NAAASP) for men aged 65 years began in England in 2009. An important element of the evidence base supporting its introduction was the economic modelling of the long‐term cost‐effectiveness of screening, which was based mainly on 4‐year follow‐up data from the Multicentre Aneurysm Screening Study (MASS) randomized trial. Concern has been expressed about whether this conclusion of cost‐effectiveness still holds, given the early performance parameters, particularly the lower prevalence of AAA observed in NAAASP.

Research impact: A narrative review

Impact occurs when research generates benefits (health, economic, cultural) in addition to building the academic knowledge base. Its mechanisms are complex and reflect the multiple ways in which knowledge is generated and utilised. Much progress has been made in measuring both the outcomes of research and the processes and activities through which these are achieved, though the measurement of impact is not without its critics. We review the strengths and limitations of six established approaches (Payback, Research Impact Framework, Canadian Academy of Health Sciences, monetisation, societal impact assessment, UK Research Excellence Framework) plus recently developed and largely untested ones (including metrics and electronic databases). We conclude that (1) different approaches to impact assessment are appropriate in different circumstances; (2) the most robust and sophisticated approaches are labour-intensive and not always feasible or affordable; (3) whilst most metrics tend to capture direct and proximate impacts, more indirect and diffuse elements of the research-impact link can and should be measured; and (4) research on research impact is a rapidly developing field with new methodologies on the horizon.

Exercises to improve function of the rheumatoid hand (SARAH): a randomised controlled trial.

BACKGROUND Disease-modifying biological agents and other drug regimens have substantially improved control of disease activity and joint damage in people with rheumatoid arthritis of the hand. However, commensurate changes in function and quality of life are not always noted. Tailored hand exercises might provide additional improvements, but evidence is lacking. We estimated the effectiveness and cost-effectiveness of tailored hand exercises in addition to usual care during 12 months. METHODS In this pragmatic, multicentre, parallel-group trial, at 17 National Health Service sites across the UK we randomly assigned 490 adults with rheumatoid arthritis who had pain and dysfunction of the hands and had been on a stable drug regimen for at least 3 months, to either usual care or usual care plus a tailored strengthening and stretching hand exercise programme. Participants were randomly assigned with stratification by centre. Allocation was computer generated and unmasked to participants and therapists delivering treatment after randomisation. Outcome assessors and all investigators were masked to allocation. Physiotherapists or occupational therapists gave the treatments. The primary outcome was the Michigan Hand Outcomes Questionnaire overall hand function score at 12 months. The analysis was by intention to treat. We calculated cost per quality-adjusted life-year. This trial is registered as ISRCTN 89936343. FINDINGS Between Oct 5, 2009, and May 10, 2011, we screened 1606 people, of whom 490 were randomly assigned to usual care (n=244) or tailored exercises (n=246). 438 of 490 participants (89%) provided 12 month follow-up data. Improvements in overall hand function were 3·6 points (95% CI 1·5-5·7) in the usual care group and 7·9 points (6·0-9·9) in the exercise group (mean difference between groups 4·3, 95% CI 1·5-7·1; p=0·0028). Pain, drug regimens, and health-care resource use were stable for 12 months, with no difference between the groups. No serious adverse events associated with the treatment were recorded. The cost of tailored hand exercise was £156 per person; cost per quality-adjusted life-year was £9549 with the EQ-5D (£17,941 with imputation for missing data). INTERPRETATION We have shown that a tailored hand exercise programme is a worthwhile, low-cost intervention to provide as an adjunct to various drug regimens. Maximisation of the benefits of biological and DMARD regimens in terms of function, disability, and health-related quality of life should be an important treatment aim. FUNDING UK National Institute of Health Research Health Technology Assessment Programme (NIHR HTA), project number 07/32/05.

A crossover randomised controlled trial of oral mandibular advancement devices for obstructive sleep apnoea-hypopnoea (TOMADO)

Rationale Mandibular advancement devices (MADs) are used to treat obstructive sleep apnoea-hypopnoea syndrome (OSAHS) but evidence is lacking regarding their clinical and cost-effectiveness in less severe disease. Objectives To compare clinical- and cost-effectiveness of a range of MADs against no treatment in mild to moderate OSAHS. Measurements and methods This open-label, randomised, controlled, crossover trial was undertaken at a UK sleep centre. Adults with Apnoea-Hypopnoea Index (AHI) 5–<30/h and Epworth Sleepiness Scale (ESS) score ≥9 underwent 6 weeks of treatment with three non-adjustable MADs: self-moulded (SleepPro 1; SP1); semi-bespoke (SleepPro 2; SP2); fully-bespoke MAD (bMAD); and 4 weeks no treatment. Primary outcome was AHI scored by a polysomnographer blinded to treatment. Secondary outcomes included ESS, quality of life, resource use and cost. Main results 90 patients were randomised and 83 were analysed. All devices reduced AHI compared with no treatment by 26% (95% CI 11% to 38%, p=0.001) for SP1, 33% (95% CI 24% to 41%) for SP2 and 36% (95% CI 24% to 45%, p<0.001) for bMAD. ESS was 1.51 (95% CI 0.73 to 2.29, p<0.001, SP1) to 2.37 (95% CI 1.53 to 3.22, p<0.001, bMAD) lower than no treatment (p<0.001 for all). Compliance was lower for SP1, which was the least preferred treatment at trial exit. All devices were cost-effective compared with no treatment at a £20 000/quality-adjusted life year (QALY) threshold. SP2 was the most cost-effective up to £39 800/QALY. Conclusions Non-adjustable MADs achieve clinically important improvements in mild to moderate OSAHS and are cost-effective. Of those trialled, the semi-bespoke MAD is an appropriate first choice. Trial registration number ISRCTN02309506.

Strengthening and stretching for rheumatoid arthritis of the hand (SARAH). A randomised controlled trial and economic evaluation

BACKGROUND The effectiveness of exercise for improving hand and wrist function in people with rheumatoid arthritis (RA) is uncertain. OBJECTIVES The study aims were (1) to estimate the clinical effectiveness and cost-effectiveness of adding an optimised exercise programme for hands and upper limbs to standard care for patients with RA; and (2) to qualitatively describe the experience of participants in the trial with a particular emphasis on acceptability of the intervention, exercise behaviours and reasons for adherence/non-adherence. DESIGN A pragmatic, multicentred, individually randomised controlled trial with an embedded qualitative study. Outcome assessors were blind to group assignment and independent of treatment delivery. SETTING Seventeen NHS trusts in England comprising 21 rheumatology and therapy departments. PARTICIPANTS Adults with RA who had pain and dysfunction of the hands and/or wrists and had been on stable medication for at least 3 months. Patients were excluded if they were under 18 years old, had undergone upper limb surgery/fracture in the last 6 months, were on a waiting list for upper limb surgery or were pregnant. INTERVENTIONS Usual care or usual care plus an individualised exercise programme. Usual care consisted of joint protection education, general exercise advice and functional splinting if required. The exercise programme consisted of six sessions of strengthening and stretching exercises with a hand therapist, daily home exercises and strategies to maximise adherence. MAIN OUTCOME MEASURES The primary outcome was the Michigan Hand Outcome Questionnaire (MHQ) overall hand function subscale score at 12 months. Secondary outcome measures included the full MHQ, pain, health-related quality of life (Short Form questionnaire-12 items), impairment (grip strength, dexterity and range of motion) and self-efficacy. European Quality of Life-5 Dimensions, medication and health-care use were collected for the health economics evaluation. Follow-up was at 4 and 12 months post randomisation. Analysis was performed on an intention-to-treat basis. RESULTS We randomised 490 patients (244 to usual care, 246 to exercise programme). Compliance with the treatments was very good (93% of usual care participants and 75% of exercise programme participants completed treatment). Outcomes were obtained for 89% of participants at 12 months (222 for usual care, 216 for exercise programme). There was a statistically significant difference in favour of the exercise programme for the primary outcome at 4 and 12 months [mean difference 4.6 points, 95% confidence interval (CI) 2.2 to 7.0 points; and mean difference 4.4 points, 95% CI 1.6 to 7.1 points, respectively]. There were no significant differences in pain scores or adverse events. The estimated difference in mean quality-adjusted life-years (QALYs) accrued over 12 months was 0.01 greater (95% CI -0.03 to 0.05) in the exercise programme group. Imputed analysis produced incremental cost-effectiveness ratio estimates of £17,941 (0.59 probability of cost-effectiveness at willingness-to-pay threshold of £30,000 per QALY). The qualitative study found the exercise programme to be acceptable and highlighted the importance of the therapist in enabling patients to establish a routine and incorporate the exercises into their lives. CONCLUSIONS The results of the Strengthening And stretching for Rheumatoid Arthritis of the Hand trial suggest that the addition of an exercise programme for RA hands/wrists to usual care is clinically effective and cost-effective when compared with usual care alone. No adverse effects were associated with the exercise programme. The economic analysis suggests that the intervention is likely to be cost-effective. STUDY REGISTRATION Current Controlled Trials ISRCTN 89936343.

Cost effectiveness of endosonography versus surgical staging in potentially resectable lung cancer: a health economics analysis of the ASTER trial from a European perspective

In the ASTER study, mediastinal staging was more accurate for patients randomised to combined endobronchial and endoscopic ultrasound, followed by surgical staging if endoscopy was negative, versus surgical staging alone. Here, we report survival, quality of life and cost effectiveness up to 6 months, for the UK, The Netherlands and Belgium, separately. Survival in the two arms of the study was similar. In all three countries, the endosonography strategy had slightly higher quality-adjusted life years over 6 months, and was cheaper. Therefore, based on clinical accuracy and cost effectiveness, we conclude that mediastinal staging should commence with endosonography.

International update on screening for abdominal aortic aneurysms : issues and opportunities.

International update on screening for abdominal aortic aneurysms : issues and opportunities.

Clinical effectiveness and cost-effectiveness results from the randomised controlled Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea–hypopnoea (TOMADO) and long-term economic analysis of oral devices and continuous positive airway pressure

BACKGROUND Obstructive sleep apnoea-hypopnoea (OSAH) causes excessive daytime sleepiness (EDS), impairs quality of life (QoL) and increases cardiovascular disease and road traffic accident risks. Continuous positive airway pressure (CPAP) treatment is clinically effective but undermined by intolerance, and its cost-effectiveness is borderline in milder cases. Mandibular advancement devices (MADs) are another option, but evidence is lacking regarding their clinical effectiveness and cost-effectiveness in milder disease. OBJECTIVES (1) Conduct a randomised controlled trial (RCT) examining the clinical effectiveness and cost-effectiveness of MADs against no treatment in mild to moderate OSAH. (2) Update systematic reviews and an existing health economic decision model with data from the Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea-hypopnoea (TOMADO) and newly published results to better inform long-term clinical effectiveness and cost-effectiveness of MADs and CPAP in mild to moderate OSAH. TOMADO A crossover RCT comparing clinical effectiveness and cost-effectiveness of three MADs: self-moulded [SleepPro 1™ (SP1); Meditas Ltd, Winchester, UK]; semibespoke [SleepPro 2™ (SP2); Meditas Ltd, Winchester, UK]; and fully bespoke [bespoke MAD (bMAD); NHS Oral-Maxillofacial Laboratory, Addenbrookes Hospital, Cambridge, UK] against no treatment, in 90 adults with mild to moderate OSAH. All devices improved primary outcome [apnoea-hypopnoea index (AHI)] compared with no treatment: relative risk 0.74 [95% confidence interval (CI) 0.62 to 0.89] for SP1; relative risk 0.67 (95% CI 0.59 to 0.76) for SP2; and relative risk 0.64 (95% CI 0.55 to 0.76) for bMAD (p < 0.001). Differences between MADs were not significant. Sleepiness [as measured by the Epworth Sleepiness Scale (ESS)] was scored 1.51 [95% CI 0.73 to 2.29 (SP1)] to 2.37 [95% CI 1.53 to 3.22 (bMAD)] lower than no treatment (p < 0.001), with SP2 and bMAD significantly better than SP1. All MADs improved disease-specific QoL. Compliance was lower for SP1, which was unpopular at trial exit. At 4 weeks, all devices were cost-effective at £20,000/quality-adjusted life-year (QALY), with SP2 the best value below £39,800/QALY. META-ANALYSIS A MEDLINE, EMBASE and Science Citation Index search updating two existing systematic reviews (one from November 2006 and the other from June 2008) to August 2013 identified 77 RCTs in adult OSAH patients comparing MAD with conservative management (CM), MADs with CPAP or CPAP with CM. MADs and CPAP significantly improved AHI [MAD -9.3/hour (p < 0.001); CPAP -25.4/hour (p < 0.001)]. Effect difference between CPAP and MADs was 7.0/hour (p < 0.001), favouring CPAP. No trials compared CPAP with MADs in mild OSAH. MAD and CPAP reduced the ESS score similarly [MAD 1.6 (p < 0.001); CPAP 1.6 (p < 0.001)]. LONG-TERM COST-EFFECTIVENESS An existing model assessed lifetime cost-utility of MAD and CPAP in mild to moderate OSAH, using the revised meta-analysis to update input values. The TOMADO provided utility estimates, mapping ESS score to European Quality of Life-5 Dimensions three-level version for device cost-utility. Using SP2 as the standard device, MADs produced higher mean costs and mean QALYs than CM [incremental cost-effectiveness ratio (ICER) £6687/QALY]. From a willingness to pay (WTP) of £15,367/QALY, CPAP is cost-effective, although the likelihood of MADs (p = 0.48) and CPAP (p = 0.49) being cost-effective is very similar. Both were better than CM, but there was much uncertainty in the choice between CPAP and MAD (at a WTP £20,000/QALY, the probability of being the most cost-effective was 47% for MAD and 52% for CPAP). When SP2 lifespan increased to 18 months, the ICER for CPAP compared with MAD became £44,066. The ICER for SP1 compared with CM was £1552, and for bMAD compared with CM the ICER was £13,836. The ICER for CPAP compared with SP1 was £89,182, but CPAP produced lower mean costs and higher mean QALYs than bMAD. Differential compliance rates for CPAP reduces cost-effectiveness so MADs become less costly and more clinically effective with CPAP compliance 90% of SP2. CONCLUSIONS Mandibular advancement devices are clinically effective and cost-effective in mild to moderate OSAH. A semi-bespoke MAD is the appropriate first choice in most patients in the short term. Future work should explore whether or not adjustable MADs give additional clinical and cost benefits. Further data on longer-term cardiovascular risk and its risk factors would reduce uncertainty in the health economic model and improve precision of effectiveness estimates. TRIAL REGISTRATION This trial is registered as ISRCTN02309506. 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. 18, No. 67. See the NIHR Journals Library website for further project information.