Cohort-Based Development and Validation of a Nomogram for Predicting Cough Variant Asthma Progression to Typical Asthma in Children

Background Cough variant asthma (CVA) in children frequently precedes typical asthma (TA), yet accurate prediction of this progression remains challenging.Methods A prospective cohort of 289 children diagnosed with CVA between June 2023 and June 2024 was followed for 12 months until June 2025. Patients were randomly divided into a training set (n = 203) and a validation set (n = 86) in a 7:3 ratio. Predictors were screened by univariate logistic regression and LASSO regression. A nomogram was constructed using the rms package in R and evaluated by ROC curves, 1000-iteration Bootstrap calibration, decision curve analysis (DCA), and Hosmer-Lemeshow tests.Results During the 12-month follow-up, 42 children (14.5%) progressed to TA. Ten independent predictors were finally selected by LASSO regression and incorporated into the nomogram: personal history of allergy (OR = 3.62, 95% CI:1.78-7.36), family history of asthma (OR = 3.18, 95% CI:1.37-7.39), poor treatment compliance (OR = 2.94, 95% CI:1.32-6.55), history of pet keeping (OR = 2.41, 95% CI: 1.11-5.24), FeNO (OR = 1.09, 95% CI:1.05-1.14), CaNO (OR = 1.16, 95% CI: 1.06-1.27), X5%pred (OR = 1.04, 95% CI:1.02-1.07), R5%pred (OR = 1.03, 95% CI:1.01-1.06), FEF25%pred (OR = 0.96, 95% CI:0.94-0.98), and MMEF%pred (OR = 0.97, 95% CI: 0.95-0.99). The nomogram showed good discrimination with AUCs of 0.863 (95% CI: 0.782-0.944) in the training set and 0.838 (95% CI:0.742-0.933) in the validation set. Hosmer-Lemeshow tests indicated good fit (training:χ2=6.7277, P = 0.5663; validation:χ2=7.7376, P = 0.4595). DCA demonstrated favourable clinical net benefit across a wide range of threshold probabilities.Conclusions This novel nomogram integrating ten key risk factors provides a preliminary and visually intuitive tool for risk stratification of CVA progression to TA in children.