Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada.
Child Health Evaluative Sciences, The Hospital for Sick Children, Toronto, Canada; Toronto Health Economics and Technology Assessment Collaborative, Toronto, Canada; Institute for Health Policy Management and Evaluation, University of Toronto, Toronto, Canada.
Ophthalmology. 2017 Aug;124(8):1108-1119. doi: 10.1016/j.ophtha.2017.03.019. Epub 2017 Apr 27.
To use patient-level microsimulation models to evaluate the comparative cost-effectiveness of early corneal cross-linking (CXL) and conventional management with penetrating keratoplasty (PKP) when indicated in managing keratoconus in Canada.
Cost-utility analysis using individual-based, state-transition microsimulation models.
Simulated cohorts of 100 000 individuals with keratoconus who entered each treatment arm at 25 years of age. Fellow eyes were modeled separately. Simulated individuals lived up to a maximum of 110 years.
We developed 2 state-transition microsimulation models to reflect the natural history of keratoconus progression and the impact of conventional management with PKP versus CXL. We collected data from the published literature to inform model parameters. We used realistic parameters that maximized the potential costs and complications of CXL, while minimizing those associated with PKP. In each treatment arm, we allowed simulated individuals to move through health states in monthly cycles from diagnosis until death.
For each treatment strategy, we calculated the total cost and number of quality-adjusted life years (QALYs) gained. Costs were measured in Canadian dollars. Costs and QALYs were discounted at 5%, converting future costs and QALYs into present values. We used an incremental cost-effectiveness ratio (ICER = difference in lifetime costs/difference in lifetime health outcomes) to compare the cost-effectiveness of CXL versus conventional management with PKP.
Lifetime costs and QALYs for CXL were estimated to be Can$5530 (Can$4512, discounted) and 50.12 QALYs (16.42 QALYs, discounted). Lifetime costs and QALYs for conventional management with PKP were Can$2675 (Can$1508, discounted) and 48.93 QALYs (16.09 QALYs, discounted). The discounted ICER comparing CXL to conventional management was Can$9090/QALY gained. Sensitivity analyses revealed that in general, parameter variations did not influence the cost-effectiveness of CXL.
CXL is cost-effective compared with conventional management with PKP in the treatment of keratoconus. Our ICER of Can$9090/QALY falls well below the range of Can$20 000 to Can$100 000/QALY and below US$50 000/QALY, thresholds generally used to evaluate the cost-effectiveness of health interventions in Canada and the United States. This study provides strong economic evidence for the cost-effectiveness of early CXL in keratoconus.
利用患者水平的微观模拟模型来评估在加拿大管理圆锥角膜时早期角膜交联（CXL）与穿透性角膜移植术（PKP）常规治疗的成本效益。
基于个体的状态转换微观模拟模型的成本效用分析。
100000 名患有圆锥角膜的个体模拟队列，他们在 25 岁时进入每个治疗组。对侧眼分别建模。模拟个体的最大寿命为 110 岁。
我们开发了 2 个状态转换微观模拟模型，以反映圆锥角膜进展的自然史以及与 CXL 相比常规 PKP 治疗的影响。我们从已发表的文献中收集数据来为模型参数提供信息。我们使用现实的参数，最大限度地提高了 CXL 的潜在成本和并发症，同时将 PKP 相关的成本和并发症降到最低。在每个治疗组中，我们允许模拟个体通过每月循环从诊断到死亡在健康状态之间移动。
对于每种治疗策略，我们计算了总费用和获得的质量调整生命年（QALY）数。费用以加元计量。成本和 QALY 以 5%贴现，将未来的成本和 QALY 转换为现值。我们使用增量成本效益比（ICER = 终生成本差异/终生健康结果差异）来比较 CXL 与常规 PKP 治疗的成本效益。
CXL 的终生成本和 QALY 估计为加元 5530 元（加元 4512 元，贴现）和 50.12 个 QALY（16.42 个 QALY，贴现）。PKP 常规治疗的终生成本和 QALY 估计为加元 2675 元（加元 1508 元，贴现）和 48.93 个 QALY（16.09 个 QALY，贴现）。与常规 PKP 治疗相比，CXL 的贴现 ICER 为加元 9090/QALY。敏感性分析表明，一般来说，参数变化不会影响 CXL 的成本效益。
与 PKP 常规治疗相比，CXL 在治疗圆锥角膜方面具有成本效益。我们的 ICER 为加元 9090/QALY，远低于加拿大和美国通常用于评估卫生干预成本效益的加元 20000 至加元 100000/QALY 和加元 50000/QALY 阈值。本研究为早期 CXL 在圆锥角膜中的成本效益提供了强有力的经济证据。
