Persistent Airflow Limitation Prediction and Risk Factor Analysis Among Asthmatic Children: A Retrospective Cohort Study.

Introduction: A minority of asthmatic children develop persistent airflow limitation (PAL), associated with an increased risk of chronic airflow obstruction and poor prognosis. This study aimed to identify risk factors for PAL and develop a prediction model to identify high-risk asthmatic children.

Methods: This retrospective study included 2072 children (5-16 years) with asthma. After a 2-year follow-up, patients were categorized into non-PAL, reversible PAL (RPAL), and irreversible PAL (IPAL) groups. Logistic regression (LR) was used to identify independent risk factors for RPAL and IPAL. A prediction model based on multivariate LR was developed and validated to identify asthmatic children at high risk of developing PAL. A nomogram was created for visualization.

Results: Among the 2072 asthmatic patients, 14.72% (n = 305) developed PAL. Asthma exacerbation history (OR 1.80, 95% CI 1.03-3.01) and poor adherence (OR 1.83, 95% CI 1.26-2.65) were independent risk factors of RPAL. Independent risk factors for IPAL were BMI over 19.0 kg/m² (OR: 1.81, 95% CI: 1.03-3.21) and a history of pneumonia (OR: 2.40, 95% CI: 1.30-4.26). The prediction model incorporated nine variables and showed good discriminatory ability, with AUC values of 0.79 (95% CI: 0.76-0.81) for the training set, 0.76 (95% CI: 0.76-0.77) for internal validation, and 0.73 (95% CI: 0.64-0.81) for temporal validation.

Conclusion: Asthma exacerbation history and poor adherence were independent risk factors for developing RPAL. BMI over 19.0 kg/m² and a history of pneumonia were risk factors for IPAL. Our prediction model effectively identified asthmatic children at high risk of developing PAL.