Sex differences in symptoms and exacerbation rates relative to lung function trajectories in asthma and/or COPD

Background: We assessed sex differences in symptoms and exacerbations relative to lung function trajectories in 9131 participants with asthma and/or COPD in the NOVELTY observational 3-year study. Methods: Lung function trajectories were identified by latent class growth trajectory modelling. Smoking status, exacerbations, and Chronic Airways Assessment Test (CAAT) score were stratified by sex and diagnosis within trajectory groups. Results: Four trajectory groups were identified: accelerated decline (AD; n=1463), slow decline (n=1850), stable (n=4396) and rapid improvement (n=1422; Figure). In females (F) vs males (M) with AD, yearly rate of FEV₁ % predicted decline with asthma was −7.0% vs −7.3% (P>0.9) and −6.0% vs −6.9% (P>0.2) with COPD. For asthma, F had higher baseline exacerbation rates vs M (e.g., in AD, mean [SD]; 0.75 [1.46] vs 0.46 [1.04], P<0.001), but similar rates in COPD (mean [SD]; 0.56 [1.03] vs 0.56 [0.99], P>0.9). Across all trajectories, F had higher mean CAAT scores vs M (asthma: mean [SD]; 15 [8] vs 12 [8], P<0.001; COPD: 18 [9] vs 15 [8], P=0.013) and lower pack-years. Similar trends were observed with FVC % predicted and z-scores. Conclusion: Groups were similar between sexes, except in AD, where F with asthma had higher CAAT scores and exacerbation rates than M. Findings highlight potential biological or behavioural differences in disease impact between sexes. erj;66/suppl_69/PA1334/F1F1F1