Chronic obstructive pulmonary disease trajectory: severe exacerbations and dynamic change in health-related quality of life

Background The life trajectory of chronic obstructive pulmonary disease (COPD) remains unknown.Patients and methods We collected data from two populations. In the first cohort, we recruited 375 patients with COPD from our hospital, and 1440 repeated assessments of quality of life (QoL) using the European Quality of Life-5 Dimensions questionnaire from 2006 to 2020. We analysed their dynamic changes using the kernel-smoothing method. The second cohort comprised 27 437 patients from the National Health Insurance (NHI) dataset with their first severe acute exacerbations (AEs) requiring hospitalisation from 2008 to 2017 were analysed for their long-term course of AEs. We employed a Cox hazard model to analyse the predictors for mortality or AEs.Results Cohorts from our hospital and NHI were male predominant (93.6 and 83.5%, respectively). After the first severe AE, the course generally comprised three phases. The first was a 1-year period of elevated QoL, followed by a 2-year prolonged stable phase with a slowly declining QoL. After the second AE, the final phase was characterised by a rapid decline in QoL. For NHI cohort, 2712 died during the 11-year follow-up, the frequency of the first AE was approximately 5 per 10 000 per day. The median time from the first to the second AE was 3 years, which decreased to less than 6 and 3 months from 4th to 5th and 8th to 9th AE, respectively. The frequency of AE was increased 10-fold and 15-fold and risk of subsequent AE was increased 12-fold and 20-fold after the 6th and the 10th AE, relative to the first. Male gender, heart failure comorbidities were associated with the risk of subsequent AE and death.Conclusions The life trajectory of COPD includes the accelerated frailty phase, as well as elevated health and prolonged stable phase after the first AE.