Background: Our aim was to evaluate if increased survival and new ventilation strategies were accompanied by a changed incidence of bronchopulmonary dysplasia (BPD) in Sweden over a decade.
Methods: Data from two Swedish population-based studies of live-born infants with gestational age (GA) 22-26 weeks, born during 2004-2007 (n=702) and 2014-2016 (n=885), were compared for survival, any BPD, moderate BPD and severe BPD and the composite outcomes of any BPD or death and severe BPD or death at 36 weeks postmenstrual age (PMA). Ventilation strategies and interventions were analysed. Any BPD was defined as the use of supplemental oxygen or any respiratory support at 36 weeks PMA, moderate BPD as nasal cannula with <30% oxygen and severe BPD as ≥30% oxygen, continuous positive airway pressure (CPAP) or mechanical ventilation.
Results: Survival to 36 weeks PMA increased from 72% to 81% (p<0.001). Total days on mechanical ventilation increased from a median of 9 to 16 days (p<0.001). High-flow nasal cannula (HFNC) was introduced between the cohorts, and days of CPAP and HFNC increased from 44 to 50 days (p<0.001). Any BPD was unchanged at 65% versus 68%. Moderate BPD increased from 37% to 47% (p=0.003), while the incidence of severe BPD decreased from 28% to 23% (p<0.046). Severe BPD or death decreased from 48% to 37% (p<0.001), while any BPD or death remained unchanged at 74% versus 75%.
Conclusion: Even though an increased survival of infants born at 22-26 weeks GA was accompanied by an increased duration of invasive and non-invasive respiratory support, the incidence of any BPD remained unchanged, while severe BPD decreased in infants alive at 36 weeks PMA.
Background: Biologics can induce remission in some patients with severe asthma, however, little is known about pre-biologic disease trajectories and their association with outcomes from biological treatment. We aimed to identify long-term trajectories of disease progression in patients initiating biologics and investigate trajectory associations with disease burden and impact on biologic therapy efficacy.
Methods: Patients in the Danish Severe Asthma Registry initiating biologic therapy between 2016-2022 were included and followed retrospectively in prescription databases starting 1995. We performed sequence analysis for inhaled corticosteroid (ICS) treatment intensity over time combined with unsupervised trajectory clustering.
Results: In total, 755 patients were included and three pre-biologic disease trajectories were identified: Chronic severe asthma (26%), Gradual onset severe asthma (35%), Recent, sudden onset severe asthma (39%). Chronic severe asthma patients were older, had the longest disease duration (35 years), the most impaired pulmonary function, the highest comorbidity prevalence and the lowest employment rate. Recent, sudden onset severe asthma patients were younger, had shorter disease duration (5 years), more tobacco exposure and the least impaired lung function. Gradual onset severe asthma had an intermediate burden of disease. The Chronic severe asthma cluster demonstrated the lowest prevalence of remission (17%) compared to the Gradual onset severe asthma (29%) and Recent onset severe asthma (32%) clusters.
Conclusions: Three pre-biologic disease trajectories were identified, with increased disease duration and activity associating with asthma- and comorbidity burden. Early intervention may be key to prevent irreversible adverse outcomes for patients with severe asthma.