Abstract
Purpose
To evaluate the cost-utility based on the quantitative relationship between glaucoma follow-up and glaucoma progression.
Methods
The Markov model was constructed and analyzed to determine the cost-effectiveness of primary open-angle glaucoma. The Markov model set up a virtual cohort of Korean over 40 years of age with early glaucoma. The costs associated with glaucoma treatment were assessed from a social point of view, and the utility was calculated using the quality adjusted life years according to the glaucoma states. Glaucoma health status was divided into 5 stages (early, middle, late, unilateral, bilateral blindness). The transition probability was set in one direction from mild to severe, and the length of each cycle was set at one year. The incremental cost effectiveness ratio (ICER) was calculated and compared with each other different follow-up periods. Sensitivity analysis was conducted to determine how the uncertainty of the variables used in this study affected the outcome.
Results
ICER of 3-month follow-up was 28,244,398 won/quality adjusted life years (QALY) compared 6-month follow-up, and ICER of 6-month follow-up was 13,615,443 won/QALY compared to 12-month follow-up. If the probability of progression of glaucoma in 6-months follow-up observations increases by more than 10% over 3-month periodic follow-up and the progression probability of 12-month follow-up increases by more than 15% follow-up compared to 3-months follow-up, 3-months follow-up was found to be a cost-effective strategy. On the other hand, 6-month follow-up was found to be cost-effective if probability of progression of 6-month follow-up was less than 10% increase of 3-month follow-up and 15% increase of 6-months follow-up.
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![]() | Figure 1.Cost-effectiveness of glaucoma patients with medication according to different follow-up periods: 3-month, 6-month, and 12-months intervals. 3 months follow up strategy showed cost of 21,091,762 won and effectiveness of 12.5 quality adjusted life years, as 1 year follow up strategy showed cost of 13,868,566 won and effectiveness of 12.1 quality adjusted life years. FU = follow up; Yr = year; M = months. |
![]() | Figure 2.Two-way sensitivity analysis of cost-effectiveness of glaucoma patients with medication on ratio of transition probability by 6-month and 12-month over 3-month follow-up periods. If the probability of progression of glaucoma in 6-months follow-up observations increases by more than 10% over 3-month periodic follow-up and the progression probability of 12-month follow-up increases by more than 15% fol-low-up compared to 3-months follow-up, 3-months follow-up was found to be a cost-effective strategy. M = months; yr = year; FU = follow up; WTP = willingness to pay. |
Table 1.
Costs used in the model
Table 2.
Utilities and other parameters used in the model
Table 3.
Cost-effectiveness of treating newly diagnosed mild open-angle glaucoma using different strategies of follow-up schedules with 3, 6, and 12 months intervals