Improving Clinical Reality in Chronic Obstructive Pulmonary Disease Economic Modelling

Abstract

BackgroundChronic obstructive pulmonary disease (COPD) is a progressive and irreversible disease responsible for the deaths of 3 million people worldwide in 2005, and predicted to be the third leading cause of death worldwide by 2030. Many COPD models developed to date have followed a Markov structure, in which patients or populations can move between defined health states over successive time periods or cycles. In COPD, health states are typically based on disease severity defined solely by lung function, as described by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. These current modelling methods may restrict the ability to reflect the disease progression/clinical pathway or clinical practice.ObjectivesGiven these limitations in previous COPD models, the authors aimed to develop a more flexible model that could improve on the description of the clinical disease pathway. The overall objective of this model was to inform the development of policies, guidelines or cost-effectiveness analyses. A second objective was to validate the model in relation to existing epidemiology studies of COPD.MethodsA patient simulation model was developed in Microsoft Excel™. The predictability of the model was tested by populating it with data from natural history of disease studies as well as with clinical trial data. Each patient moves through the model with demographic characteristics randomly generated from a set distribution. These characteristics determine the risk of clinical events occurring in the model.ResultsThe validation with these studies found the model to have generally good predictive ability, yielding in this way a good degree of external validity.ConclusionsThe micro-simulation model is a flexible approach for modelling COPD that allows consideration of complex COPD treatment pathways. The model was found to be generally robust in terms of predicting clinical outcomes of published studies when tested against other studies. It has significant potential as a tool for supporting future COPD treatment positioning decisions as well as to inform the development of policies, guidelines or cost-effectiveness analyses.

Cost-effectiveness of indacaterol/glycopyrronium in comparison with salmeterol/fluticasone combination for patients with moderate-to-severe chronic obstructive pulmonary disease: a LANTERN population analysis from Singapore

“…Singapore healthcare has a mixed financing model, comprising a combination of out-of-pocket payments by the individual, individual insurance, mandatory personal medical savings accounts (Medisave), mandatory health insurance that covers catastrophic inpatient admission episodes (MediShield Life) and government subsidies for healthcare services through public healthcare institutions. (22) A previously published patient-level simulation model (23,24) was used to compare the costs and outcomes of patients with COPD managed with IND/GLY and SFC from the public healthcare perspective in Singapore (Fig. 1).…”

“…Data from published trials was used for validating the model, as described in the previously published paper. (23) A cohort of patients (n = 100,000) was generated, where each patient was assigned a unique set of baseline characteristics using mean values and variance-covariance matrices derived from patient-level trial data. Using Monte Carlo simulation methods, a simulated patient moved through the model.…”

“…Detailed descriptions of the parameters used in the model have been provided in the previously published paper. (23) However, two parameters, the Transition Dyspnea Index and St George's Respiratory Questionnaire, were not considered for the present cost-effectiveness analysis, as these were more related to treatment switching. Since the comparator was an ICS combination, pneumonia rates and costs were later added to the model due to the established evidence of risk of pneumonia with ICS use.…”

Development and validation of the Evaluation Platform In COPD (EPIC): a population-based outcomes model of COPD for Canada

“…The external validity tests were based on the reported outcomes from the placebo arms of two independent clinical trials: TOwards a Revolution in COPD Health (TORCH)(41) and Understanding Potential Long-Term Impacts on Function with Tiotropium (UPLIFT)(42). These studies have been used by other COPD modeling groups as external validity targets and their use here also provides cross-validity tests between EPIC and existing COPD models(18,19,43–47). The external validity tests involved creating samples that mimicked the study sample of TORCH and UPLIFT to compare three quantities: rate of overall exacerbations, rate of severe exacerbations, and percentage of patients who died during follow-up.…”

Patient Heterogeneity in Health Economic Decision Models for Chronic Obstructive Pulmonary Disease: Are Current Models Suitable to Evaluate Personalized Medicine?

“…Three new models also participated. The simulation model of Asukai et al was published in 2013 [18] [19,20]. The model of Dal Negro et al was also presented at the ISPOR 17 th annual European Congress 2014 [21].…”