Abstract
Purpose:
New minimally invasive glaucoma surgeries (MIGS) and devices are emerging to aid in lowering IOP and reduce patients’ reliance on topical medications. The iStent trabecular micro-bypass stent (Glaukos Corporation, Laguna Hills, CA) is an example of these MIGS devices; it has garnered much attention, as it is minimally invasive and effective in reducing patients’ dependence on glaucoma medications. It has data supporting its use as adjunctive therapy at the time of cataract surgery for patients who are on multiple glaucoma medications. However, a major challenge hindering adoption of these MIGS has been the perceived cost. With many health care systems evolving into cost-based models, analyses of cost, as well as efficacy and safety, are becoming increasingly important. The purpose of this study is to perform a cost effectiveness analysis comparing use of the iStent at the time of phacoemulsification versus the use of glaucoma medication within the Ontario Health Insurance Plan (OHIP).
Methods:
Primary economic analysis was performed by constructing a Makov model using TreeAge Pro 2013 to conduct cost-effectiveness analysis from the public third-party payer (Ontario Health Insurance Plan) perspective. Cost and effectiveness of three treatment strategies: medical therapy, cataract surgery and simultaneous iStent insertion, and cataract surgery only were compared over a 5-year period in managing patients with cataract and glaucoma whose intra-ocular pressures were not adequately controlled by two medications. In light of uncertainty of some parameters, we performed probabilistic sensitivity analysis to evaluate the robustness of the base-case results.
Results:
The primary outcome measure was quality adjusted life years (QALYs). The incremental cost-effectiveness of iStent at the time of cataract surgery over glaucoma medications only is $6824 per quality-adjusted life year. By comparison, the incremental cost-effectiveness of cataract surgery only over glaucoma medications is $4179 per quality-adjusted life year.
Conclusions:
This analysis suggests that the use of iStent at the time of phacoemulsification is a cost-effective option for managing patients with mild to moderate open-angle glaucoma and cataract. These results, in conjunction with studies of efficacy and safety, may be useful in delineating the role of the iStent in our glaucoma treatment paradigm.
Keywords: 460 clinical (human) or epidemiologic studies: health care delivery/economics/manpower