Economic evaluation of medication, laser trabeculoplasty and filtering surgeries in treating patients with glaucoma in the US

Objective: Despite the significant clinical and economic burden associated with glaucoma, studies evaluating the long-term costs of existing treatments are limited. This study compared the 5-year costs of three treatment strategies: medication, laser trabeculoplasty, and filtering surgeries in managing patients with primary open-angle glaucoma whose intra-ocular pressures were not adequately controlled by two medications. Research design and methods: A Markov model was developed to simulate the transition of treatment progression over a 5-year period to evaluate the total treatment costs associated with each strategy. In the medication arm, medications were the only available treatment, whereas in the laser trabeculoplasty and surgery arms, patients would receive concomitant medications both at the time of the procedure and in subsequent years. Treatment states were determined by the rate of success in controlling patients' intra-ocular pressure in each year. The distribution of treatment states and the transition probabilities between these states were derived from published literature, adjusted or supplemented by the authors' own treatment experiences. Costs assessed in the model included treatment, complications associated with each treatment, and physician office visits obtained from published literature and standardized fees and schedules. Results: The 5-year cumulative costs were approximately $6571, $4838 and $6363 for patients in the medication, laser trabeculoplasty, and filtering surgery arms, respectively. Costs of third-line medication, first-line medication following laser trabeculoplasty, and post-surgery complications had the greatest impact on the model results in the medication, laser trabeculoplasty, and filtering surgery arms, respectively. Probabilistic sensitivity suggested the results were statistically significant (p < 0.001), favoring the use of laser trabeculoplasty. Conclusions: Over 5 years laser trabeculoplasty was associated with the lowest total costs compared to treatment by medication alone or by filtering surgery for patients who were not adequately controlled by two medications. Future development of glaucoma treatment should focus on reducing the need for post-procedure medical therapy as well as lowering the rate of post-procedure complications. Limited by the availability of the transition probabilities in published literature, the model results need to be validated by prospective or retrospective observational studies.