Silent Lung Risk: 4 Percent of Indian Teens Show Asymptomatic Bronchial Hyperresponsiveness, APEAL Study Finds

The study presented the following key findings:

• 4.0% of adolescents met the criteria for asymptomatic BHR.
• Prevalence varied by city: Mumbai (5.6%), Delhi (4.5%), Bengaluru (4.2%), and Mysuru (2.3%).
• Younger adolescents were more susceptible (odds ratio [OR] = 1.48).
• PM2.5 exposure was a strong risk factor: exposure between 64.1–124.8 µg/m³ increased BHR risk by 83% (OR = 1.83), and levels above 124.8 µg/m³ more than doubled the risk (OR = 2.56).
• Underweight adolescents were at greater risk of severe airflow limitation.
• Interestingly, being overweight appeared to have a protective effect, although obesity showed a similar trend, it was not statistically significant due to fewer participants in that category.

According to the authors, the results highlight the limitations of symptom-based asthma screening, which can miss early airway changes in children who appear healthy. They advocate for routine lung function testing in schools, especially in pollution-heavy urban centers to enable early identification and prevention of chronic respiratory diseases.

Despite some limitations—such as its single-time assessment and city-specific sampling differences—the study's multicentric approach and use of international protocols, such as BOLD and GAN, lend credibility to its findings. The authors urge the need for long-term monitoring of affected individuals and targeted public health strategies.

Dr. Mahesh and his team concluded, “The APEAL study highlights a silent epidemic of early airway changes in Indian adolescents, calling for a shift in asthma detection strategies to include objective lung testing, especially in high-risk urban settings.”

Reference:

Mahesh, P. A., Ullah, M. K., Greeshma, M. V., Patil, S., Samdarshi, P., Veerabhadraiah, H., Khayum, A., Agrawal, T., Phuleria, H. C., Wellenius, G., Nori-Sarma, A., Ponnuraj, L., Kagalavadi Mahadevaswamy, S. K., Mayigaiah, S. C., Thimmulappa, R. K., & Mohan, A. Prevalence of Asymptomatic Bronchial Hyperresponsiveness in Indian Adolescents: Insights From the APEAL Study. Clinical & Experimental Allergy. https://doi.org/10.1111/cea.70110