First-time detection of treatable congenital heart disease - a study of school-aged children in the community of three regions in China

Congenital heart disease (CHD) is a leading cause of birth defect-related morbidity and mortality globally. While neonatal screening programs exist, the undiagnosed burden of treatable CHD among school-aged children in low- and middle-income countries (LMICs) like China remains sparse. This manuscript aimed to determine the epidemiology and identify factors associated with the First-Time Detection of Eligible-Treatment congenital heart disease (FTET-CHD) in a community-based sample of school children. A large-scale cross-sectional study was conducted from June 2024 to June 2025 across three Chinese regions (Yunnan, Xinjiang, and Chongqing). A total of 1,024,531 children aged 3–18 years were screened. Diagnosis was confirmed by echocardiography. Among the 3,376 children diagnosed with CHD, 484 with treatable CHD were enrolled and categorized as either FTET-CHD (no prior diagnosis) or prior-detected CHD (PDET-CHD). Demographic, clinical, and socioeconomic data were collected. Multivariable logistic regression and SHAP (Shapley Additive Explanations) analysis were employed to identify key factors associated with FTET-CHD. Of the 484 children with treatable CHD (median age 10 years; 40.7% male), a striking 67.1% (n = 325) were identified as FTET-CHD. Significant geographical variation was observed, with Xinjiang having a significantly higher proportion of FTET-CHD than Yunnan (82% vs. 58.5%; adjusted OR = 4.818, 95% CI: 2.510–9.230). Key factors associated with reduced odds of FTET-CHD (i.e., protective against delayed diagnosis) included having commercial health insurance (vs. public insurance; OR = 0.191, 95% CI: 0.051–0.716) and higher annual household healthcare expenditure (OR = 0.972 per 1000 CNY, 95% CI: 0.950–0.995). Paradoxically, FTET-CHD children reported significantly higher quality of life (QoL) scores than PDET-CHD children (88.0 vs. 78.0). SHAP analysis confirmed geographic region and QoL score as the most influential predictors in the model. This study revealed a critically still high prevalence of previously undiagnosed treatable CHD among school-aged children in China, indicating an existing gap in early detection. The findings underscored the impact of socioeconomic and geographic disparities on diagnostic delay. Advocacy for school-age echocardiographic screening programs, especially in low- and middle-income countries (LMICs), is essential to reduce CHD-related burden and ensure timely treatment.