Aris Angelis

Pars plana vitrectomy for vitreomacular traction syndrome: a systematic review and metaanalysis of safety and efficacy

Purpose: To determine the safety and efficacy of pars plana vitrectomy for vitreomacular traction. Methods: Articles reporting visual acuity change before and after pars plana vitrectomy were selected using a systematic literature review with predefined eligibility criteria. Visual acuities were converted to logarithm of the minimum angle of resolution (logMAR), weighted for study size, and pooled across studies. Safety outcomes were also pooled across studies. Results: Twenty-one of 460 articles were eligible. Mean (±standard deviation) logMAR visual acuity improved from 0.67 ± 0.55 to 0.42 ± 0.45 (n = 259 eyes) after pars plana vitrectomy (from 20/94 to 20/53 Snellen). In series of at least 20 eyes, mean visual acuity improved in all 5 studies (sign test, P = 0.0625). Of 392 eyes, 9.2% lost visual acuity, 11.7% were unchanged, and 64.3% improved; 32.9% of 217 eyes gained ≥2 Snellen lines. The most common postoperative complications were cataract (34.7% of 304 eyes; 63.2% of 68 phakic eyes), epiretinal membrane (5.7% of 348 eyes), and retinal detachment (4.6% of 348 eyes). Cataract surgery was undertaken in 10.5% of eyes. Conclusion: The visual acuity gains after pars plana vitrectomy for vitreomacular traction are relatively modest, but visual acuity change may not fully reflect symptomatic relief.

Symptomatic vitreomacular adhesion.

Background: Symptomatic vitreomacular adhesion describes symptomatic loss of visual function as a result of vitreous traction at the macula. Methods: Literature review. Results: Symptomatic vitreomacular adhesion can occur in isolation as vitreomacular traction, which may lead to the development of a macular hole, or it may occur alongside epiretinal membrane. It is likely to be associated with age-related macular degeneration and possibly diabetic maculopathy, although this is less certain. The treatment depends largely on the cause, but options include observation, vitrectomy, and pharmacologic vitreolysis. Small uncontrolled trials have also explored the use of an intravitreal gas bubble as a means of releasing VMA. If all cases of sVMA are considered together, then the burden of illness is substantial, with a prevalence of ∼0.35 per 100 population (excluding epiretinal membrane). Furthermore, there may be many more cases of undiagnosed sVMA. Conclusion: The recent introduction of ocriplasmin is likely to increase interest in sVMA. Clinical trials suggest that it has a role in the treatment of vitreomacular traction and Stages 1 to 3 macular holes but not primarily as a treatment of epiretinal membrane. Its role in other diseases associated with VMA remains to be determined.

Vitreous attachment in age-related macular degeneration, diabetic macular edema, and retinal vein occlusion: a systematic review and metaanalysis.

Purpose: To determine if there is an association of vitreous attachment and wet age-related macular degeneration (AMD), diabetic macular edema, and retinal vein occlusion. Methods: Systematic review and metaanalysis. Results: Sixteen of 1,025 articles were eligible. In wet AMD, the prevalence of vitreomacular adhesion and posterior vitreous detachment was 23% (654 eyes) and 41% (251), respectively. Vitreomacular adhesion prevalence was 2.15 times that of controls (95% confidence interval, 1.34–3.48; p = 0.002) and 2.54 times that of dry AMD (confidence interval, 0.88–7.36; p 0.09); posterior vitreous detachment prevalence was lower than controls (relative risk 0.77; confidence interval, 0.64–0.93; p = 0.007) and dry AMD (0.56; confidence interval, 0.27–1.14; p = 0.11). It was not possible to determine the prevalence of vitreous attachment in diabetic macular edema, but vitreomacular traction was present in 29% of 188 surgical cases. The prevalence of posterior vitreous detachment in eyes with central and branch retinal vein occlusion was 30% (56 eyes) and 31% (71 eyes), respectively, versus 25% (64 eyes) in controls. Conclusion: Observational studies of sufficient quality indicate that eyes with wet AMD have double the expected prevalence of vitreomacular adhesion and are less likely to have a posterior vitreous detachment. More controlled studies of diabetic macular edema and retinal vein occlusion are needed.

Applying Multiple Criteria Decision Analysis to Comparative Benefit-Risk Assessment Choosing among Statins in Primary Prevention

Decision makers in different health care settings need to weigh the benefits and harms of alternative treatment strategies. Such health care decisions include marketing authorization by regulatory agencies, practice guideline formulation by clinical groups, and treatment selection by prescribers and patients in clinical practice. Multiple criteria decision analysis (MCDA) is a family of formal methods that help make explicit the tradeoffs that decision makers accept between the benefit and risk outcomes of different treatment options. Despite the recent interest in MCDA, certain methodological aspects are poorly understood. This paper presents 7 guidelines for applying MCDA in benefit-risk assessment and illustrates their use in the selection of a statin drug for the primary prevention of cardiovascular disease. We provide guidance on the key methodological issues of how to define the decision problem, how to select a set of nonoverlapping evaluation criteria, how to synthesize and summarize the evidence, how to translate relative measures to absolute ones that permit comparisons between the criteria, how to define suitable scale ranges, how to elicit partial preference information from the decision makers, and how to incorporate uncertainty in the analysis. Our example on statins indicates that fluvastatin is likely to be the most preferred drug by our decision maker and that this result is insensitive to the amount of preference information incorporated in the analysis.

Social and economic costs and health-related quality of life in non-institutionalised patients with cystic fibrosis in the United Kingdom.

BackgroundThis study aimed to determine the societal economic burden and health-related quality of life (HRQOL) of cystic fibrosis (CF) patients in the UK.MethodsA bottom-up cost-of-illness, cross-sectional, retrospective analysis of 74 patients was conducted aiming to estimate the economic impact of CF. Data on demographic characteristics, health resource utilisation, informal care, productivity losses and HRQOL were collected from questionnaires completed by patients or their caregivers. HRQOL was measured with the EuroQol 5-domain (EQ-5D) instrument.ResultsUsing unit costs for 2012 we found that the average annual cost for a CF patient was €48,603, with direct health care costs amounting to €20,854 (42.9 % of total costs), direct non-health care costs being €21,528 (44.3 %) and indirect costs attributable to productivity losses being €6,222 (12.8 %). On average, the largest expenditures by far were accounted for by informal care (44.1 %), followed by medications (14.5 %), acute hospitalisations (13.9 %), early retirement (9.1 %) and outpatient and primary health care visits (7.9 %). Sharp differences existed depending on whether CF patients were in need of caregiver help (€76,271 versus €26,335). In adult CF patients, mean EQ-5D index scores were 0.64 (0.93 in the general population) and mean EQ-5D visual analogue scale scores were 62.23 (86.84 in the general population); among caregivers, these scores were 0.836 and 80.85, respectively.DiscussionOur analysis highlights the importance of the economic and quality of life consequences of CF from a societal perspective. The results highlight that beyond conventional costs such as acute hospitalisations, medication and outpatient and primary care visits, indirect costs related to informal care and early retirement, have significant societal implications. Similarly, our analysis showed that the average EQ-5D index score of adult CF patients was significantly lower than in the general population, an indication that a methodological bias may exist in using the latter in economic analyses.ConclusionCF poses a significant cost burden on UK society, with non-health care and indirect costs representing 57 % of total average costs, and HRQOL being considerably lower than in the general population.

Using health technology assessment to assess the value of new medicines: results of a systematic review and expert consultation across eight European countries

BackgroundAlthough health technology assessment (HTA) systems base their decision making process either on economic evaluations or comparative clinical benefit assessment, a central aim of recent approaches to value measurement, including value based assessment and pricing, points towards the incorporation of supplementary evidence and criteria that capture additional dimensions of value.ObjectiveTo study the practices, processes and policies of value-assessment for new medicines across eight European countries and the role of HTA beyond economic evaluation and clinical benefit assessment.MethodsA systematic (peer review and grey) literature review was conducted using an analytical framework examining: (1) ‘Responsibilities and structure of HTA agencies’; (2) ‘Evidence and evaluation criteria considered in HTAs’; (3) ‘Methods and techniques applied in HTAs’; and (4) ‘Outcomes and implementation of HTAs’. Study countries were France, Germany, England, Sweden, Italy, Netherlands, Poland and Spain. Evidence from the literature was validated and updated through two rounds of feedback involving primary data collection from national experts.ResultsAll countries assess similar types of evidence; however, the specific criteria/endpoints used, their level of provision and requirement, and the way they are incorporated (e.g. explicitly vs. implicitly) varies across countries, with their relative importance remaining generally unknown. Incorporation of additional ‘social value judgements’ (beyond clinical benefit assessment) and economic evaluation could help explain heterogeneity in coverage recommendations and decision-making.ConclusionMore comprehensive and systematic assessment procedures characterised by increased transparency, in terms of selection of evaluation criteria, their importance and intensity of use, could lead to more rational evidence-based decision-making, possibly improving efficiency in resource allocation, while also raising public confidence and fairness.

Pars plana vitrectomy for diabetic macular edema: a systematic review, meta-analysis, and synthesis of safety literature

Purpose: To assess the risk and benefit of pars plana vitrectomy for diabetic macular edema. Methods: The authors conducted a systematic literature review using PubMed, EMBASE, Web of Science, and Cochrane Central Database of Controlled Trials until September 2014. The population was patients with diabetic macular edema, intervention vitrectomy, comparator macular laser or observation, and efficacy outcome visual acuity and central retinal thickness. Safety outcomes were intraoperative and postoperative surgical complications. The efficacy meta-analysis included only randomized controlled trials. The safety analysis included prospective, retrospective, controlled, and uncontrolled studies. Results: Five studies were eligible for the efficacy meta-analysis (n = 127 eyes) and 40 for the safety analysis (n = 1,562 eyes). Combining follow-up intervals from 6 to 12 months, the meta-analysis found a nonsignificant 2 letter visual acuity difference favoring vitrectomy, and a significant 102 &mgr;m greater reduction in central retinal thickness favoring vitrectomy, but a post hoc subgroup analysis found that a 6-month central retinal thickness benefit reversed by 12 months. The most frequent complications were retinal break (7.1%), elevated intraocular pressure (5.2%), epiretinal membrane (3.3%), and vitreous hemorrhage (2.4%). Cataract developed in 68.6% of 121 phakic eyes. Conclusion: Vitrectomy produces structural and functional improvements in select eyes with diabetic macular edema, but the visual gains are not significantly better than with laser or observation. No major safety concerns were identified.

Preferences on policy options for ensuring the financial sustainability of health care services in the future: results of a stakeholder survey.

BackgroundUniversal access to health care in most western European countries has been a given for many decades; however, macroeconomic developments and increased pressure on health care budgets could mean the status quo cannot be maintained. As populations age, a declining proportion of economically active citizens are being required to support a larger burden of health and social care, while increasing availability of novel technologies for extending and improving life continues to push health care costs upwards. With health expenditure continuing to rise as a proportion of national income, concerns are raised about the current and future financial sustainability of Organisation for Economic Co-Operation and Development (OECD) health care systems. Against this backdrop, a discussion about options to fund health care in the future, including whether to raise additional health care finance (and the ways to do so), reallocate resources and/or ration services becomes very pertinent.ObjectiveThis study elicits preferences among a group of key stakeholders (payers, providers, government, academia and health-related industry) on the issue of health care financial sustainability and the future funding of health care services, with a view to understanding the different degrees of acceptability between policy interventions and future funding options as well as their feasibility.Study Design and ParticipantsWe invited 842 individuals from academia, other research organisations (eg. think tanks), national health services, providers, health insurance organisations, government representatives and health-related industry and related advisory stakeholders to participate in an online survey collecting preferences on a variety of revenue-generating mechanisms and cost/demand reducing policies. Respondents represented the 28 EU member states as well as Norway, Iceland, Switzerland, Australia, Russian Federation, Canada and New Zealand.ResultsWe received 494 responses to our survey from all stakeholder groups. Across all groups, the highest preference was for policies to modify lifestyle and implement more extensive screening within risk groups for high burden illnesses. There was a broad consensus not to reallocate resources from social security/education. Between stakeholders, there were differences of opinion between industry/advisory and a range of other groups, with industry being generally more in favour of market-based interventions and an increased role for the private sector in health care financing/delivery. Conversely, stakeholders from academia, government, national health services and insurance were relatively more in favour of more restrictive purchasing of new and expensive technologies, and (to varying extent) of higher income/corporate taxes. Taxes on cigarettes/alcohol were by far considered the most politically feasible option.ConclusionsAccording to this study, policy options that are broadly acceptable across stakeholder groups with different inherent interests exist but are limited to lifestyle modification, screening interventions and excise taxes on harmful products. Representatives from the private sector tend to view solutions rooted in the private sector as both effective and politically feasible options, while stakeholders from academia and the public sector seem to place more emphasis on solutions that do not disproportionately impact certain population groups.

Resource allocation and priority setting in health care: a multi-criteria decision analysis problem of value?

A methodological approach is needed for allocating health care resources in an efficient and fair way that gives legitimacy to decisions. Currently, most priority setting approaches tend to focus on single or limited benefit dimensions, even though the value of new health care interventions is multi-dimensional. Explicit elicitation of social value trade-offs is usually not possible and decision-makers often adopt intuitive or heuristic modes for simplification purposes as part of an ad hoc decision-making process which might diminish the reasonableness and credibility of the decisions. In this paper, we suggest that multi-criteria decision analysis could provide a more comprehensive and transparent approach in health care to systematically capture decision-makers’ concerns, compare value trade-offs and elicit their value preferences. We conclude that such methods could inform the development of a decision support system in health care, contributing towards more efficient, rational and legitimate resource allocation decisions.

Applying Multiple Criteria Decision Analysis (MCDA) in the context of HTA: an experimental case study on metastatic colorectal cancer

Objectives Past research has indicated that Multiple Criteria Decision Analysis (MCDA) could be used as an alternative methodology for assessing the value of new medical technologies in the context of Health Technology Assessment (HTA). The objective of this study is to apply in practice an MCDA framework for the value assessment of a set of therapeutic options in metastatic colorectal cancer through a simulation exercise based on MCDA principles.