Emparan C, Wolters H, Laukötte M, Senninger N
Department of Surgery, Fundacion Hospital Calahorra, Calahorra, La Rioja 26500, Spain.
Transplant Proc. 2005 Jun;37(5):2069-71. doi: 10.1016/j.transproceed.2005.03.008.
Markov models are employed in economic analyses to evaluate all possible expectations in a dilemna. The introduction of a new clinical protocol (Basiliximab induction with calcineurin-sparing protocols) for a group of kidney transplant recipients receiving organs from marginal donors was validated with a Markov simulation model, demonstrating the usefulness of combining simulation with Bayesian estimation methods for analysis of cost-effectiveness data collected alongside a clinical trial. We sought to determine whether calcineurin-sparing protocols using anti-interleukin-2/antibody induction (Simulect) would show a beneficial effect on initial kidney function and reduce transplantation costs upon admission, clinical incidences, graft function, and complications during the first month after transplant.
A Markov Chain Monte Carlo (MCMC) was used to estimate a system of generalized linear models relating costs and outcomes to a kidney transplant process affected by treatment under alternative therapies. The Markov simulation model was established following three chains: a calcineurin-free regimen with Basiliximab induction (chain A); a calcineurin-sparing protocol with Basiliximab induction (chain B); and a conventional immunosuppressive regimen (chain C). The MCMC draws were used as parameters in simulations that yielded inferences about the relative cost-effectiveness of the novel therapy under a variety of scenarios. After designing the Markov chain and cohorts, 31 patients from the "old-to-old" program were assigned; eight to chain A; eight to chain B; and 15 to chain C. A year after transplantation a cost-benefit study was performed guided by the three branches of the Markov model.
The Markov model showed a benefit of induction therapies in elderly patients. A cost-benefit model showed that after a year, there was a clear benefit from calcineurin-free plus Basiliximab induction therapies, with a slight benefit from calcineurin-sparing protocols.
Markov models are extremely useful when introducing new clinical therapies. The approach allows flexibility in assessing treatment using various premises and quantifies the global effect of parametric uncertainty on a decision maker's confidence to adopt one therapy over another. In our transplant program, a cost-effective analysis of outcomes in old patients using the Markov model showed a clear benefit of calcineurin-sparing protocols with Basixilimab induction.
马尔可夫模型用于经济分析，以评估困境中的所有可能预期。针对一组接受边缘供体器官的肾移植受者引入一种新的临床方案（用巴利昔单抗诱导并采用钙调神经磷酸酶抑制剂减量方案），通过马尔可夫模拟模型进行验证，证明了将模拟与贝叶斯估计方法相结合用于分析与临床试验同时收集的成本效益数据的有用性。我们试图确定使用抗白细胞介素-2/抗体诱导（舒莱）的钙调神经磷酸酶抑制剂减量方案是否会对初始肾功能产生有益影响，并降低移植后第一个月入院时的移植成本、临床发病率、移植物功能和并发症。
采用马尔可夫链蒙特卡罗（MCMC）方法估计广义线性模型系统，该系统将成本和结果与替代疗法下受治疗影响的肾移植过程相关联。马尔可夫模拟模型按照三条链建立：巴利昔单抗诱导的无钙调神经磷酸酶方案（链A）；巴利昔单抗诱导的钙调神经磷酸酶抑制剂减量方案（链B）；以及传统免疫抑制方案（链C）。MCMC抽样用作模拟中的参数，从而得出关于新疗法在各种情况下相对成本效益的推断。在设计马尔可夫链和队列后，分配了31名“老年对老年”项目的患者；8名分配到链A；8名分配到链B；15名分配到链C。移植一年后，在马尔可夫模型的三个分支指导下进行了成本效益研究。
马尔可夫模型显示诱导疗法对老年患者有益。成本效益模型显示，一年后，无钙调神经磷酸酶加巴利昔单抗诱导疗法有明显益处，钙调神经磷酸酶抑制剂减量方案有轻微益处。
引入新的临床疗法时，马尔可夫模型极为有用。该方法在使用各种前提评估治疗时具有灵活性，并量化参数不确定性对决策者选择一种疗法而非另一种疗法的信心的总体影响。在我们的移植项目中，使用马尔可夫模型对老年患者的结果进行成本效益分析显示，巴利昔单抗诱导的钙调神经磷酸酶抑制剂减量方案有明显益处。
