Abstract Rationale Chronic obstructive pulmonary disease (COPD) is a heterogeneous and dynamic condition characterized by variable trajectories in lung function, symptoms, and exacerbations. Traditionally, these outcomes have been studied separately, yet they are interdependent and may jointly reflect the underlying activity of the disease. The emerging concept of disease stability integrates these domains into a multidimensional state defined by the absence of clinically meaningful deterioration in lung function, symptom burden, or exacerbation frequency. Achieving and maintaining such stability may indicate low disease activity, whereas transitions from stable to unstable states mark periods of increased activity and risk. However, the frequency, persistence, and clinical determinants of disease stability in real-world COPD populations remain largely unexplored. Methods We performed a retrospective longitudinal cohort study using data from the Swedish National Airway Register (SNAR) including patients ≥18 years with physician-confirmed COPD and repeated measurements of FEV₁, COPD Assessment Test (CAT), and exacerbations between 2013-2024. Stability was assessed over 6- and 12-month windows. Component criteria were defined as: no exacerbations, CAT score change 2 points, and absolute FEV₁ change 0.10 L from baseline. Composite “3-component stability” required meeting all criteria simultaneously. Transitions between stable and unstable states were evaluated longitudinally, and determinants of stability were identified using logistic regression models. Results Among 123,163 registered individuals, 7,648 met inclusion criteria with complete longitudinal data. Mean age was 69 ± 9 years, 57% were female, and mean FEV₁ % predicted 56 ± 18%. Over 6 months, only 11% achieved 3-component stability, declining to 8% at 12 months. Figure 1 illustrates the marked variability across components: at 6 months, 73% were exacerbation-free, 48% maintained stable symptoms, and only 26% met the FEV₁ stability threshold. Similar patterns were observed at 12 months, underscoring lung function as the most labile component. Of those stable at 6 months, 61% remained stable at 12 months. Conclusions In routine clinical practice, COPD stability—across lung function, symptoms, and exacerbations—is rare and often transient. Exacerbation-free status is common, but physiological and symptomatic stability are less so, suggesting that disease stability is multidimensional and fragile. Achieving sustained multidomain stability represents a clinically meaningful but challenging therapeutic target in COPD management. This abstract is funded by: None
Vanfleteren et al. (Fri,) studied this question.