Abstract Rationale The 2023 Global Initiative for Chronic Obstructive Lung Disease (GOLD) report classifies individuals with chronic obstructive pulmonary disease (COPD) who have experienced ≥2 moderate (outpatient) or ≥ 1 severe (emergency department or hospitalization) exacerbations within the last year as being at high risk of future exacerbation (category E). Objective This study aimed to investigate the risk of exacerbation and death associated with the individual components of the GOLD E category. Study Design and Methods We conducted a retrospective cohort study using health administrative data from Ontario, Canada (2007–2018). Individuals ≥65 years of age with physician-diagnosed COPD were followed for up to five exacerbations, until their death, or the study period ended. After each exacerbation, individuals were assigned to one of three GOLD subgroups: E moderate (≥2 moderate), E severe (≥1 severe), and AB (≤1 moderate). Under a landmark analysis framework, Fine-Gray subdistribution hazards (sdHR) competing risk models were created for each event and risk of exacerbation and death was estimated. Results There were 279,798 individuals included. Individuals in the GOLD E moderate subgroup were at higher risk of future exacerbation (COPD, chronic obstructive pulmonary disease exacerbations 3-5=1.15-1.18) and lower risk of death (sdHR exacerbations 3-5=0.84-0.97) than GOLD AB individuals. In comparison, patients in the GOLD E severe subgroup were at lower risk of future exacerbation (sdHR exacerbations 2-5=0.92-0.97), but higher risk of death (sdHR exacerbations 2-5=1.65-1.84). Conclusion These findings indicate that COPD patients in the GOLD E moderate subgroup have different risk of future exacerbation and death than individuals in the GOLD E severe subgroup.
Munn et al. (Fri,) studied this question.