233919 Simulating visual outcomes in the developing world: Estimating the burden and assessing the cost-effectiveness of treating glaucoma in the Barbados and Ghana

Monday, November 8, 2010 : 1:15 PM - 1:29 PM

John S. Wittenborn, BS , Public Health Economics Program, RTI International, Atlanta, GA
David Rein, PhD , Public Health Economics Program, RTI International, Atlanta, GA
Visual loss and blindness are estimated to contribute to 8.2 percent of all years of life lived with a disability worldwide, and of the 161 million people that suffer from blindness due to disease, over 90 percent are concentrated in the poorest parts of the developing world. However, with little or no direct measurement, the true epidemiology and burden of visual disease in developing countries is largely unknown. We adapted a previously validated model to estimate the incidence, prevalence, and social and economic burden of primary open angle glaucoma in the context of two developing nation populations; Barbados, which was the source of disease incidence data, and Ghana, whose population may have similar propensity to glaucoma but exhibits different demographic and economic conditions. We then assess the cost-effectiveness of several hypothetical glaucoma screening and treatment interventions in each population. We estimate glaucoma-attributable visual loss results in 0.006 disability adjusted life years (DALY) lost and $100 in net productivity costs per person each year in Barbados. We found that all screening and treatment interventions we assessed would be cost-effective in Barbados. Relative to Barbados, we predict Ghana suffers 36 percent lower prevalence of glaucoma and 60 and 70 percent lower prevalence of visual impairment and blindness, respectively, resulting in annual losses of 0.002 DALYs and $10 in productivity costs per person. No simulated interventions requiring population screening or guideline-level care were cost-effective, but a hypothetical intervention of one-time laser surgery on self-referring patients with limited visual field loss was cost-effective.

Learning Areas:
Biostatistics, economics

Learning Objectives:
1. Demonstrate potential benefits and challenges of using visual disease simulation models to estimate disease burden in unobserved developing nation populations. 2. Describe why a single visual disease can manifest widely varying levels of burden in two populations exhibiting differing levels of development. 3. Design an evaluation process to simulate visual disease models in multiple populations differing in demographic and economic development.

Keywords: Simulation, Vision Care

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: John Wittenborn, BS, is an associate economist in RTIís Public Health Economics Program. His research at RTI focuses on cost-effectiveness and cost-benefit analyses, disease modeling, cost-of-illness studies, and Medicare payment analyses. Mr. Wittenborn has experience in simulation model development; econometrics; and economic, financial, and statistical analysis. Wittenborn is the lead programmer on the CR-MEDS model, an agent-based, Monte Carlo simulation of the cost-effectiveness of screening treatment for multiple eye diseases. In additional to visual health, Wittenborn has created models of chronic kidney disease, and hepatitis C. Before joining RTI, Mr. Wittenborn was a research assistant at Georgetown Economic Services and an assistant research analyst at Space Applications Corporation.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.