Abstract
Asthma control in children is often challenging. This retrospective cohort study aimed to investigate the potential contribution of small airway function in predicting asthma control within a 2- to 3-month period following the initial diagnosis in preschool children with asthma. A total of 219 preschool children diagnosed with asthma were enrolled, and their follow-up was conducted by pediatric pulmonary physicians. Clinical history and lung function results were collected for analysis. To identify risk factors associated with poor asthma control, a multivariable regression model was employed. Sixty-nine of the patients (31.5%) exhibited poor asthma control. Poor adherence to therapy (14.5% vs. 6.0%, p = 0.038) and the presence of severe airway hyperresponsiveness (AHR) (20.6% vs. 1.6%, p < 0.001) were more prevalent in the group with poor control. Additionally, baseline forced expiratory volume in 1 s in predicting (94.5% vs. 101.4%, p = 0.001), forced expiratory flows (FEF)(50)% (66.1% vs. 86.0%, p < 0.001), FEF(75)% (60.9% vs. 75.3%, p = 0.001), and FEF(25-75)% (70.9% vs. 86.0%, p < 0.001) were significantly lower in the poorly-controlled group than those of well-controlled group. There was no significant difference in forced vital capacity in predicting (FVC%) between the two groups (92.4% vs. 96.7%, p = 0.093). Multivariable regression model unveiled initial severe AHR (OR 8.595, 95%CI 1.241-59.537, p = 0.021) and decreased FEF(50)% (OR 0.971, 95%CI 0.949-0.994, p = 0.012) were significantly associated with short-term poor asthma control. Preschool children with asthma who exhibites initial severe AHR and/or decreased FEF(50)% faces an elevated risk of encountering poor asthma control during the subsequent 2-3 months.