Screening women aged 65 years or over for abdominal aortic aneurysm: a modelling study and health economic evaluation.

BACKGROUND: Abdominal aortic aneurysm (AAA) screening programmes have been established for men in the UK to reduce deaths from AAA rupture. Whether or not screening should be extended to women is uncertain. OBJECTIVE: To evaluate the cost-effectiveness of population screening for AAAs in women and compare a range of screening options. DESIGN: A discrete event simulation (DES) model was developed to provide a clinically realistic model of screening, surveillance, and elective and emergency AAA repair operations. Input parameters specifically for women were employed. The model was run for 10 million women, with parameter uncertainty addressed by probabilistic and deterministic sensitivity analyses. SETTING: Population screening in the UK. PARTICIPANTS: Women aged ≥ 65 years, followed up to the age of 95 years. INTERVENTIONS: Invitation to ultrasound screening, followed by surveillance for small AAAs and elective surgical repair for large AAAs. MAIN OUTCOME MEASURES: Number of operations undertaken, AAA-related mortality, quality-adjusted life-years (QALYs), NHS costs and cost-effectiveness with annual discounting. DATA SOURCES: AAA surveillance data, National Vascular Registry, Hospital Episode Statistics, trials of elective and emergency AAA surgery, and the NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP). REVIEW METHODS: Systematic reviews of AAA prevalence and, for elective operations, suitability for endovascular aneurysm repair, non-intervention rates, operative mortality and literature reviews for other parameters. RESULTS: The prevalence of AAAs (aortic diameter of ≥ 3.0 cm) was estimated as 0.43% in women aged 65 years and 1.15% at age 75 years. The corresponding attendance rates following invitation to screening were estimated as 73% and 62%, respectively. The base-case model adopted the same age at screening (65 years), definition of an AAA (diameter of ≥ 3.0 cm), surveillance intervals (1 year for AAAs with diameter of 3.0-4.4 cm, 3 months for AAAs with diameter of 4.5-5.4 cm) and AAA diameter for consideration of surgery (5.5 cm) as in NAAASP for men. Per woman invited to screening, the estimated gain in QALYs was 0.00110, and the incremental cost was £33.99. This gave an incremental cost-effectiveness ratio (ICER) of £31,000 per QALY gained. The corresponding incremental net monetary benefit at a threshold of £20,000 per QALY gained was -£12.03 (95% uncertainty interval -£27.88 to £22.12). Almost no sensitivity analyses brought the ICER below £20,000 per QALY gained; an exception was doubling the AAA prevalence to 0.86%, which resulted in an ICER of £13,000. Alternative screening options (increasing the screening age to 70 years, lowering the threshold for considering surgery to diameters of 5.0 cm or 4.5 cm, lowering the diameter defining an AAA in women to 2.5 cm and lengthening the surveillance intervals for the smallest AAAs) did not bring the ICER below £20,000 per QALY gained when considered either singly or in combination. LIMITATIONS: The model for women was not directly validated against empirical data. Some parameters were poorly estimated, potentially lacking relevance or unavailable for women. CONCLUSION: The accepted criteria for a population-based AAA screening programme in women are not currently met. FUTURE WORK: A large-scale study is needed of the exact aortic size distribution for women screened at relevant ages. The DES model can be adapted to evaluate screening options in men. STUDY REGISTRATION: This study is registered as PROSPERO CRD42015020444 and CRD42016043227. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Analysis of clinical benefit, harms, and cost-effectiveness of screening women for abdominal aortic aneurysm.

BACKGROUND: A third of deaths in the UK from ruptured abdominal aortic aneurysm (AAA) are in women. In men, national screening programmes reduce deaths from AAA and are cost-effective. The benefits, harms, and cost-effectiveness in offering a similar programme to women have not been formally assessed, and this was the aim of this study. METHODS: We developed a decision model to assess predefined outcomes of death caused by AAA, life years, quality-adjusted life years, costs, and the incremental cost-effectiveness ratio for a population of women invited to AAA screening versus a population who were not invited to screening. A discrete event simulation model was set up for AAA screening, surveillance, and intervention. Relevant women-specific parameters were obtained from sources including systematic literature reviews, national registry or administrative databases, major AAA surgery trials, and UK National Health Service reference costs. FINDINGS: AAA screening for women, as currently offered to UK men (at age 65 years, with an AAA diagnosis at an aortic diameter of ≥3·0 cm, and elective repair considered at ≥5·5cm) gave, over 30 years, an estimated incremental cost-effectiveness ratio of £30 000 (95% CI 12 000-87 000) per quality-adjusted life year gained, with 3900 invitations to screening required to prevent one AAA-related death and an overdiagnosis rate of 33%. A modified option for women (screening at age 70 years, diagnosis at 2·5 cm and repair at 5·0 cm) was estimated to have an incremental cost-effectiveness ratio of £23 000 (9500-71 000) per quality-adjusted life year and 1800 invitations to screening required to prevent one AAA-death, but an overdiagnosis rate of 55%. There was considerable uncertainty in the cost-effectiveness ratio, largely driven by uncertainty about AAA prevalence, the distribution of aortic sizes for women at different ages, and the effect of screening on quality of life. INTERPRETATION: By UK standards, an AAA screening programme for women, designed to be similar to that used to screen men, is unlikely to be cost-effective. Further research on the aortic diameter distribution in women and potential quality of life decrements associated with screening are needed to assess the full benefits and harms of modified options. FUNDING: UK National Institute for Health Research Health Technology Assessment programme.

Discrete Event Simulation for Decision Modeling in Health Care: Lessons from Abdominal Aortic Aneurysm Screening.

Markov models are often used to evaluate the cost-effectiveness of new healthcare interventions but they are sometimes not flexible enough to allow accurate modeling or investigation of alternative scenarios and policies. A Markov model previously demonstrated that a one-off invitation to screening for abdominal aortic aneurysm (AAA) for men aged 65 y in the UK and subsequent follow-up of identified AAAs was likely to be highly cost-effective at thresholds commonly adopted in the UK (£20,000 to £30,000 per quality adjusted life-year). However, new evidence has emerged and the decision problem has evolved to include exploration of the circumstances under which AAA screening may be cost-effective, which the Markov model is not easily able to address. A new model to handle this more complex decision problem was needed, and the case of AAA screening thus provides an illustration of the relative merits of Markov models and discrete event simulation (DES) models. An individual-level DES model was built using the R programming language to reflect possible events and pathways of individuals invited to screening v. those not invited. The model was validated against key events and cost-effectiveness, as observed in a large, randomized trial. Different screening protocol scenarios were investigated to demonstrate the flexibility of the DES. The case of AAA screening highlights the benefits of DES, particularly in the context of screening studies.

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

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.

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.

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.

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.