JMIR Publications

ABSTRACT

Background:

Childhood asthma research in China faces challenges such as fragmented outpatient data, limited biospecimen availability, and insufficient population coverage. Traditional cohort studies are resource-intensive and poorly adaptable to routine outpatient settings, underscoring the need for innovative models.

Objective:

To establish the Clinical Registry of Childhood Asthma (CRCA), a digitally enhanced, real-world prospective cohort, through creation of a dynamically updated repository with age- and phenotypically diverse participants, thereby addressing current infrastructure limitations.

Methods:

The CRCA was launched in March 2024 as an ongoing longitudinal study, enrolling children (<18 years) with cough and/or wheezing lasting >1 month at the Children’s Hospital of Chongqing Medical University, a a tertiary pediatric referral center serving Southwest China. The study employed a real-world cohort design, integrating symptom-driven recruitment strategies with a multimodal data collection framework that included: (1) standardized electronic medical records (EMRs), (2) structured electronic patient-reported outcomes (ePROs), and (3) systematic biobanking of residual biospecimens. Follow-up visits were scheduled every 4–6 months, with additional visits as clinically indicated.

Results:

Between March 2024 and May 2025, we organized 54 weekly outpatient sessions. A total of 356 children (median age 4.2 years) were enrolled from 1890 patient visits, 67.1% of which were under 6 years old. Diagnoses included 33.7% with confirmed asthma, 23.0% with excluded asthma, and 43.3% with suspected asthma. The initial follow-up rate was 25.7%, with significant differences among age groups (34.4% in children aged over 6 years vs 21.8% in those under 6 years, P=.02) and diagnostic groups (highest in confirmed asthma cases: 43.7%, P<.001). Children under 6 years had a higher prevalence of suspected asthma (51.5% vs 26.5%, P<.001), and confirmed asthma cases (median 6.4 years) were significantly older than those with suspected (median 4.1 years) and excluded asthma (median 4.3 years, P<.001). Different age groups and asthma diagnostic groups showed distinct spectra of other disease diagnoses. Questionnaire data showed that parental perception of asthma diagnosis did not fully align with clinical diagnosis (only 62.9% of confirmed asthma cases were recognized by parents). Children aged ≥6 years showed a higher rate of family asthma history (21.7% vs 12.1%, P=.04) and household water leakage (25.0% vs 13.7%, P=.02). Respiratory infections were the main risk factor for wheezing episodes (57.7%), with higher prevalence in confirmed (68.5%) and suspected asthma groups (61.5%) compared to the excluded asthma group (34.9%, P<.001). A total of 1995 residual biospecimens were collected, with the research potential of these residual biospecimens demonstrated in our previous studies.

Conclusions:

The CRCA establishes the feasibility of a digitally enhanced, real-world cohort model for childhood asthma research in resource-constrained settings. This innovative approach successfully enables inclusive enrollment of participants spanning diverse ages and phenotypic profiles.