Modelling the lifetime economic consequences of glaucoma in France

Systematic methodological review of health state values in glaucoma cost-utility analyses

IMPORTANCE

Describing the characteristics and sources of health state utility values and reporting practice in the literature of cost-utility analyses facilitates an understanding of the level of the transparency, validity, and generalizability of cost-utility analyses. Improving the quality of reporting will support investigators in describing the incremental value of emerging glaucoma interventions.

OBJECTIVE

To describe the state of practice among published glaucoma cost-utility analysis studies, focusing on valuation of health and the quality of reporting.

EVIDENCE REVIEW

We searched several databases including Medline, CINHAL, Embase, Web of Science, Scopus, Biosis previews, the Health Economic Evaluations Database, and the NHS Economic Evaluation Database (NHS EED). We included full-text, English, published cost-utility analyses of glaucoma interventions with quality-adjusted life years (QALYs) as the primary outcome measure to calculate incremental cost-utility ratios. Excluded studies were non-English language, reviews, editorials, protocols, or other types of economic studies (cost-benefit, cost-minimization, cost-effectiveness). Study characteristics, operational definitions of glaucoma health states and health state utilities were extracted. The original source of the health utility was reviewed to determine the scale of measurement and the source of preference weighting. Items from the Systematic Review of Utilities for Cost-Effectiveness (SpRUCE checklist) were used to assess the reporting and quality of health utilities in glaucoma CUA.

FINDINGS

43 CUAs were included, with 11 unique sources of health utilities. A wide range of health utilities for the same Hodapp-Parrish-Anderson glaucoma health states were reported; ocular hypertension (0.84-0.95), mild (0.68-0.94), moderate (0.57-0.92), advanced (0.58-0.88), severe/blind (0.46-0.76), and bilateral blindness (0.26-0.5). Most studies reported the basis for using health utilities (34, 79%) and any assumptions or adjustments applied to the health utilities (22, 51%). Few studies reported a framework for assessing the relevance of health utilities to a decision context (8, 19%). Even fewer (3, 7%) applied a systematic search strategy to identify health utilities and used a structured assessment of quality for inclusion. Overall, reporting has not improved over time.

CONCLUSIONS AND RELEVANCE

This review describes that few CUAs describe important rationale for using health state utility values. Including additional details on the search, appraisal, selection, and inclusion process of health utility values improves transparency, generalizability and supports the assessment of the validity of study conclusions. Future investigations should aim to use health utilities on the same scale of measurement across health states and consider the source and relevance to the decision context/purpose of conducting that cost-utility study.

Cost-Utility Analysis of STN1013001, a Latanoprost Cationic Emulsion, versus Other Latanoprost Formulations (Latanoprost) in Open-Angle Glaucoma or Ocular Hypertension and Ocular Surface Disease in France

Purpose

To investigate the cost utility of STN1013001, a latanoprost cationic emulsion, versus Latanoprost in patients with open-angle glaucoma or ocular hypertension (OAG/OHT) and concomitant ocular surface disease (OSD) in France.

Methods

An early Markov model, including 7 health states and a 1-year cycle length, was developed to estimate the cost utility of STN1013001 versus Latanoprost from the French health system perspective over a 5-year time horizon. The model was populated with pooled data (treatment adherence, quality of life, disease progression, and resource utilization) collected, via a questionnaire, from a convenience sample of 5 French glaucoma specialists. Remaining data were retrieved from published sources. Half-cycle correction and 2.5% real social discount rate were applied to costs (in €2020), life years saved (LYS), and quality-adjusted life years (QALYs). The incremental cost-utility ratio (ICUR) was contrasted against the informal willingness-to-pay (WTP) range for incremental LYS or QALY gained (€30,000–€50,000) suggested for France. One-way and probabilistic sensitivity analyses tested the robustness of the baseline ICUR.

Results

Over a 5-year time horizon, STN1013001 resulted in an incremental 0.35 QALYs gained at an incremental cost of €7.39 compared to Latanoprost, resulting in an ICUR of €21.26. This is well below the lower limit of the unofficial WTP range proposed for France. Sensitivity analyses confirmed the robustness of the baseline results.

Conclusion

Once on the market, STN1013001 will provide the French health system with a cost-effective treatment versus Latanoprost for OAG/OHT + OSD patients. These results should be confirmed by future economic evaluations carried out alongside empirical trials.

Current Knowledge and Attitudes Concerning Cost-Effectiveness in Glaucoma Pharmacotherapy: A Glaucoma Specialists Focus Group Study

Background

Rising healthcare costs motivate continued cost-reduction efforts. To help lower costs associated with open-angle glaucoma (OAG), a prevalent, progressive disease with substantial direct and indirect costs, clinicians need to understand the cost-effectiveness of intraocular pressure (IOP)-lowering pharmacotherapies. There is little published information on clinicians’ knowledge and attitudes about cost-effectiveness in glaucoma treatment.

Purpose

This pilot focus group study aimed to explore clinician attitudes and perspectives around the costs and cost drivers of glaucoma therapy; the implementation of cost-effectiveness decisions; the clinical utility of cost-effectiveness studies; and the cost-effectiveness of available treatments.

Methods

Six US glaucoma specialists participated in two separate teleconferencing sessions (three participants each), managed by an independent, skilled moderator (also a glaucoma specialist) using a discussion guide. Participants reviewed recent publications (n=25) on health economics outcomes research in glaucoma prior to the sessions.

Results

Participants demonstrated a clear understanding of the economic burden of glaucoma therapy and identified medications, diagnostics, office visits, and treatment changes as key cost drivers. They considered cost-effectiveness an appropriate component of treatment decision-making but identified the need for additional data to inform these decisions. Participants indicated that there were only a few recent studies on health economics outcomes in glaucoma which evaluate parameters important to patient care, such as quality of life and medication adherence, and that longitudinal data were scant. In addition to efficacy, participants felt patient adherence and side-effect profile should be included in economic evaluations of glaucoma pharmacotherapy. Recently approved medications were evaluated in this context.

Conclusion

Clinicians deem treatment decisions based on cost-effectiveness data as clinically appropriate. Newer IOP-lowering therapies with potentially greater efficacy and favorable side-effect and adherence profiles may help optimize cost-effectiveness. Future studies should include: clinicians’ perspectives; lack of commercial bias; analysis of long-term outcomes/costs; more comprehensive parameters; real-world (including quality-of-life) data; and a robust Markov model.

Measuring Disability in Glaucoma

BACKGROUND

Glaucomatous visual field loss can have far-reaching and debilitating consequences on an individual, affecting one's ability to perform many important tasks. Although assessment of glaucoma-related disability constitutes an important part of clinical care, there remains a lack of organized, detailed information on the most suitable methods to capture disability in glaucoma.

PURPOSE

This review details the available methods to measure glaucoma-related disability and highlights important findings from studies utilizing these various methods.

METHODS

The literature was reviewed to identify papers evaluating disability in glaucoma and findings were summarized by research methodology used and area of impairment.

RESULTS

Identified methods for capturing glaucoma-related disability included qualitative descriptions, glaucoma-specific quality of life questionnaires, vision-specific questionnaires, general health questionnaires, functional domain-specific questionnaires, evaluation of task performance, event assessment (ie, falls and motor vehicle accidents), and real-world behavior (ie, daily physical activity). Findings using these methods show a strong relationship between glaucoma and/or glaucoma severity and difficulties with reading, driving, mobility, and other tasks such as prehension and facial recognition. In addition, glaucoma has financial and psychological implications on the patient, and can affect caregivers in some cases as well.

CONCLUSIONS

A wide variety of research tools have been used to characterize the disability resulting from glaucoma. Together, these tools show that glaucoma affects many abilities which are important for independent living. Strengths and limitations of the various research techniques are discussed so that future studies may use the method(s) most suitable for answering the research question posed.

Direct healthcare costs of glaucoma treatment

AIMS

To report the complete lifetime direct healthcare costs of glaucoma treatment in a database of 1136 patients attending the Glaucoma Clinic at Glasgow Royal Infirmary, Glasgow, UK.

METHOD

The database was interrogated to identify all patients who had initiated treatment at the Glaucoma Clinic at Glasgow Royal Infirmary, and who had subsequently died of natural causes. The healthcare resource use based cost assessment was based on two aspects of the direct National Health Service cost: drug costs (prescribed medications) and non-drug costs (inpatient or outpatient/and surgical or procedure costs).

RESULTS

106 patients (53 men, 53 women) were identified for whom there were lifetime treatment data. The mean lifespan of the patients was 80.5 years, and the mean number of years attending the glaucoma clinic was 7.05 years (range 1-22 years). The mean cost of glaucoma treatment over the lifetime of the patients was £3001, with an annual mean cost per patient of £475. Non-drug and drug costs made up 66% and 34% respectively, of the lifetime costs.

CONCLUSIONS

This is the only study to directly assess the lifetime treatment costs of glaucoma. Awareness of the costs of glaucoma treatment may be of increased importance in these financially challenging times.

Glaucoma costs in Denmark in treatment naive patients

PURPOSE

To describe the costs and providers of glaucoma treatment in Denmark.

METHODS

Analyses were based on National Register data. Glaucoma/OHT patients were identified by their first prescription for glaucoma medication (ATC-codes) in the Danish Register of Medicinal Product Statistics 2002-2007. Patients had used no glaucoma medication for 6 months. Data for 2007 were sampled cross-sectionally for a budgetary analysis of glaucoma (ICD10 code) medication and services consumed in the primary and secondary health care services. Patients were categorized according to their number of treatment changes.

RESULTS

The Danish annual incidence rate of glaucoma was estimated at 1.2 per 1000 adult persons. Thirty-seven per cent of patients (men 44%, mean age 68 years; women 56%, mean age 71 years) persisted with their initial treatment regimen, 21% had changed to a second regimen, and 43% had experienced ≥ 3 regimens. Treatment costs increased with the number of sequential regimens. Annual glaucoma costs (health care sector perspective) were €305 for patients under their initial regimen, increasing to €740 with ≥ 3 regimens. Drug costs accounted for 57% of total cost.

CONCLUSIONS

Drugs represented the major cost of glaucoma, and those costs increased, obviously, with the number of treatment changes.

Contribution of modeling approaches and virtual populations in transposing the results of clinical trials into real life and in enlightening public health decisions

Modeling consists in aggregating separate pieces of knowledge, according to a given structure and rules. It allows studying the behavior of more or less complex systems by simulation techniques. Modeling is used in different state-of-the-art technological domains (meteorology, aeronautics). Its use has grown for the evaluation of medicines and medical devices, from conception to prescription (marketing authorization, reimbursement, price setting and re-registrations). It follows a scientific approach and is the object of good practice recommendations. Coupling models to virtual populations allows obtaining realistic results at the population level, testing diagnostic or therapeutic strategies, as well as estimating the consequences of transposing the results of clinical trials to the population. Through examples, the participants of the Round Table analyzed the contributions of the coupling of models and realistic virtual populations, and proposed guidelines for their judicious and systematic use.

Economic considerations of the diagnosis and management for glaucoma in the developed world

PURPOSE OF REVIEW

This review evaluates the last 18-month literature related to costs and glaucoma. The emphasis is to look at evidence as a big picture and evaluate the critical points and challenges in methodology, current knowledge and future research.

RECENT FINDINGS

On the basis of simulation models, treating glaucoma appears to be cost-effective compared with no treatment. The results of the simulation models are, however, not consistent regarding when to treat ocular hypertension and when comparing different therapeutic interventions. Most models simulated starting treatment with prostaglandins compared with other medications, whereas one study simulated also initial laser therapy which appeared to be cost saving compared with medical therapy. The models utilized input data both from randomized controlled trials (ideal outcomes) and observational studies (with incomplete and selective reporting). Models suffer from unreliability of data, for example data from randomized diagnostic trials, empirical data of utility values and glaucoma-induced visual disability are limited.

SUMMARY

As the number of economic evaluations increases, the interpretation and evaluation of their extensive reporting appears very challenging. The published studies highlight the range of uncertainties due to the shortages of our current knowledge and evidence. There is a need for reliable and 'realistic' data for economic evaluations, preferably data from pragmatic randomized trials of 'usual patients'. Similar to emphasizing the cost-effectiveness of care, there is a need to evaluate the expected payback and cost-effectiveness of research interventions. However, even high-quality evidence cannot help our patients if we do not adopt cost-effective interventions.