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

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.