Long-term follow-up studies of adults with well-characterised asthma are sparse.
We aimed to examine long-term remission and change in disease severity over 30 years in adults with asthma.
125 individuals diagnosed with asthma between 1974-1990 at a Danish respiratory and allergy clinic, based on history and objective assessments, were included. At follow-up (2017-19), participants completed questionnaires and had spirometry, bronchodilator reversibility, airway responsiveness and blood biomarkers measured. Based on these assessments, participants were classified as having either active asthma, clinical remission (no symptoms or prescribed asthma medication within the last year) or complete remission (FeNO <50 ppb, no bronchodilator reversibility, no airway hyperresponsiveness and no airflow limitation). Changes in severity were determined according to GINA guidelines based on symptom control and currently prescribed medication.
At follow-up, 25% (n=31) and 15% (n=19), respectively, had clinical and complete remission. Our analyses showed that longer duration of symptoms before the initial assessment (OR 0.86, 95% CI 0.75-0.98) was associated with a lower chance of asthma remission. At follow-up, 30% had well-controlled asthma compared with none at baseline. Female sex, previous severe exacerbation(s), and older age at baseline were associated with uncontrolled asthma at follow-up. Blood-eosinophil count (≥0.3×10/l) and prescribed ICS at baseline were associated with being prescribed medium/high dose ICS at follow-up.
Despite 30 years of follow-up, asthma rarely remits in adults, especially in individuals with longer duration and presumably more severe disease. Initial signs of pronounced disease activity were associated with uncontrolled asthma at follow-up.

Copyright © 2020. Published by Elsevier Inc.