Related Experiment Video
Updated: Feb 2, 2026

A Quick Phenotypic Neurological Scoring System for Evaluating Disease Progression in the SOD1-G93A Mouse Model of ALS
Published on: October 6, 2015
Lifetime trajectory simulation of chronic disease progression and comorbidity development
Zhecheng Zhu1, Bee Hoon Heng1, Kiok Liang Teow1
1Health Services & Outcomes Research, National Healthcare Group, Singapore.
Introduction:
Comorbidity is common in elderly patients and it imposes heavy burden on both individual and the whole healthcare system. This study aims to gain insights of comorbidity development by simulating the lifetime trajectory of disease progression from single chronic disease to comorbidity.
Methods:
Eight health states spanning from no chronic condition to comorbidity are considered in this study. Disease progression network is constructed based on the seven-year retrospective data of around 700,000 residents living in Singapore central region. Microsimulation is applied to simulate the process of aging and disease progression of a synthetic new-born cohort for the entire lifetime.
Results:
Among the 40 unique trajectories observed from the simulation, the top 10 trajectories covers 60% of the cohort. Timespan of most trajectories from birth to death is 80 years. Most people progress to at risk at late 30 s, develop the first chronic condition at 50 s or 60 s, and then progress to complications at 70 s. It is also observed that the earlier one person develops chronic conditions, the more life-year-lost is incurred.
Discussion:
The lifetime disease progression trajectory constructed for each person in the cohort describes how a person starts healthy, becomes at risk, then progresses to one or more chronic conditions, and finally deteriorates to various complications over the years. This study may help us have a better understanding of chronic disease progression and comorbidity development, hence add values to chronic disease prevention and management.
Related Concept Videos
Orthogonal Trajectories
Chronic Kidney Disease I: Introduction
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
Chronic Obstructive Pulmonary Disease-I: Introduction
Chronic Obstructive Pulmonary Disease-V: Management
Smoking Cessation

