POSC302 Discrete Event Simulation in Severe COPD: A Feasibility Study Using DICE Methodology

Abstract

To assesses the feasibility of probabilistic, discrete event simulation (DES) in moderate to severe chronic obstructive pulmonary disease (COPD). To validate the model results against outcomes reported from a German COPD disease management program (DMP). Probabilistic DES was implemented using the Discretely Integrated Condition Event (DICE) framework by Caro et. al. Distributions defining model mortality and exacerbation rates were based on an epidemiological study by Rothnie et al. (99,574 patients, mean follow-up of 4.9 years) from the UK and implemented in the model through 18 patient profiles to support sub-group analyses. Exacerbations and pharmaceutical therapy with stepwise escalation/de-escalation were considered according to German treatment guidelines. Severe exacerbation costs were based on the German full inpatient statistics calculating weighted mean costs for Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups 2-4 according to ICD-10 J44. Moderate exacerbation costs were based on official German reimbursement catalogues to account for outpatient visits and acute drug treatment. A total of 9,000 patients (500 per profile) were simulated to achieve stable Results: Modelled survival and exacerbation outcomes matched the Rothnie data without any major differences. Total model costs vs. reported DMP costs were: 3,145€ vs. 3,603€ (GOLD 2); 4,415€ vs. 4,579€ (GOLD 3); 5,662€ vs. 6,233€ (GOLD 4). Reported DMP cost were covered by confidence intervals of model Results: Total model runtime was 515 seconds. Generally, probabilistic DES for COPD is feasible with the DICE framework. The most recent DICE engine improved model runtime significantly and enables sensitivity analyses on standard PC hardware. Although modelled mean costs differed slightly from reported DMP costs, it is important to note that this model included COPD-related healthcare costs only while the DMP reported total healthcare costs.