On non-biologic treatment clinical remission in adult-onset asthma: A 20-year cohort study in Taiwan

Research on asthma clinical remission has mainly focused on severe asthma with biologic therapy. This study aimed to determine the prevalence and predictors of clinical remission in patients with adult-onset asthma receiving non-biologic treatment. Data were retrieved from the Chang Gung Research Database (CGRD), the largest electronic medical records-based database in Taiwan. A total of 14,935 patients diagnosed with asthma between 2002 and 2022 were screened. There were 8043 on-treatment patients enrolled. We defined on-treatment clinical remission as follows: (1) absence of symptoms (ACT score ≥20); (2) no use of systemic steroids; (3) no clinical exacerbation for at least 12 months. These patients were categorized according to clinical remission status: those who achieved clinical remission (n = 2185), and those who had persistent asthma (n = 5858). The on non-biologic treatment clinical remission rate of adult-onset asthma was 27.2 %. Factors associated with persistent asthma included female, smoking history, forced expiratory volume in 1 s <50 %, high blood eosinophil count, sputum fungal colonization, worse baseline asthma control test (ACT) score, high inhaled corticosteroid dose, and acute exacerbation and hospitalization in the previous 1 year. Baseline ACT score <23 had the best predictive value (area under the curve [AUC] = 0.616) for persistent asthma, while a combination of sputum fungal colonization, blood eosinophil count >300 cell/ul, baseline ACT score <23, and acute exacerbation (AE) last year were presented the greatest predictive value of persistent asthma (AUC = 0.673). In this 20-year cohort study, nearly one third of the asthmatics achieved clinical remission under non-biologic treatment. Patients at the highest risk of persistent asthma require timely and targeted treatment strategies.