Medical decision making for patients with Parkinson disease under Average Cost Criterion

Abstract

Parkinson's disease (PD) is one of the most common disabling neurological disorders and results in substantial burden for patients, their families and the as a whole society in terms of increased health resource use and poor quality of life. For all stages of PD, medication therapy is the preferred medical treatment. The failure of medical regimes to prevent disease progression and to prevent long-term side effects has led to a resurgence of interest in surgical procedures. Partially observable Markov decision models (POMDPs) are a powerful and appropriate technique for decision making. In this paper we applied the model of POMDP's as a supportive tool to clinical decisions for the treatment of patients with Parkinson's disease. The aim of the model was to determine the critical threshold level to perform the surgery in order to minimize the total lifetime costs over a patient's lifetime (where the costs incorporate duration of life, quality of life, and monetary units). Under some reasonable conditions reflecting the practical meaning of the deterioration and based on the various diagnostic observations we find an optimal average cost policy for patients with PD with three deterioration levels.

Modelling the Cost Effectiveness of Treatments for Parkinsonʼs Disease

“…Evaluations of surgical options Diagnostic evaluations Lindgren et al [24] Smala et al [29] Hudry et al [32] Haycox et al [36] Findley et al [43] Kristiansen et al [47] Goulionis and Vozikis [49] Hjelmgren et al [50] Antonini et al [55] Van Laere et al [58] Dodel et al [62] Context (2) sensitivity analyses performed, the authors concluded robust results, although cost-effectiveness measures were not shown. Smala et al [29] presented a Markov model based on the progression of PD.…”

“…Goulionis and Vozikis, [49] Greece (independent study) Hjelmgren et al, [50] Sweden (independent study)…”

“…Goulionis and Vozikis [49] presented a Markov decision model that evaluated the cost effectiveness of DBS compared with best medical treatment (before DBS). Mild, moderate and severe symptoms (referred to as 'adverse events') were chosen as Markov states.…”

“…Instead of directly determining deterioration of the patient's health, which could not be ascertained using clinical data, patients' health was linked to possible observations such as activities of daily living, induced tremor and motor functions. Because patient progression was unobservable, Goulionis and Vozikis [49] chose a partially observable Markov model as their modelling approach.…”

“…Instead of considering cost effectiveness using ICERs, Goulionis and Vozikis [49] performed their calculations with the aim of optimizing the total lifetime costs. The calculated thresholds at which medical treatment was more cost effective than DBS were linked to the inital probability of having mild, moderate or severe adverse events.…”