Cost-utility analysis of treating mild stage normal tension glaucoma by surgery in China: a decision-analytic Markov model

Many individuals suffer from normal tension glaucoma (NTG) in China. This study utilized Markov models to evaluate the cost-utility of applying many medications and surgery for mild-stage NTG when disease progression occurred at a mild stage.

A 10-year decision-analytic Markov model was developed for the cost-utility analysis of treating mild-stage NTG with surgery and increased application of medication. We hypothesized that all 100,000 samples with a mean age of 64 were in mild stages of NTG. Transitional probabilities from the mild to moderate to severe stages and the basic parameters acquired from the CNTGS were calculated. Incremental cost-utility ratios (ICUR) were calculated for treating all patients with NTG by probabilistic sensitivity analysis (PSA) and Monte Carlo simulation. One-way sensitivity analysis were conducted by adjusting the progression rate, cost of medications or trabeculectomy, cost of follow-up, and surgical acceptance rate.

The ICUR of treating mild stage NTG with medication over 10 years was $12743.93 per quality-adjusted life years (QALYs). The ICUR for treating mild stage NTG patients with a 25% and 50% surgery rate with medication were $8798.93 and $4851.93 per QALYs, respectively. In this model, the cost-utility of treating NTG was sensitive to disease progression rate, surgical treatment rate, and medication costs.

According to the results of the cost-utility analysis, it was a reasonable and advantageous strategy to administer a lot of medication and surgery for NTG in the mild stages of the disease. In the model, the greater the probability of patients undergoing surgery, the strategy becomes more valuable.