A multinational longitudinal study has shown that bronchodilator responsiveness may be linked to an increased risk of developing chronic airflow obstruction over time.
in the BOLD study, published in The Lancet, investigators tracked their respiratory health of 3,701 participants aged 40 years and older for an average of 9.1 years. They recruited participants from 41 municipalities across 34 countries between 2003 and 2016, with follow-up assessments conducted between 2019 and 2021. Assessments included spirometry tests and health surveys, with bronchodilator responsiveness (BDR) at baseline defined according to ATS/ERS 2022 criteria.
At baseline, 6% of participants exhibited BDR. Over the follow-up period, the overall prevalence of chronic airflow obstruction (CAO) was 8%, with the highest prevalence recorded in Benin (34%) and the lowest in Morocco (0%). Participants with BDR who developed CAO reported higher exposure to dusty environments and more respiratory symptoms, indicating that environmental and symptomatic factors may contribute to disease progression.
The study revealed that participants with BDR had a 36% higher risk (relative risk [RR] = 1.36, 95% confidence interval [CI] = 1.04–1.80) of developing CAO compared with those without BDR. This elevated risk was more pronounced among women (RR = 1.45, 95% CI = 1.09–1.91) compared with men (RR = 1.07, 95% CI = 0.51–2.24). Among never-smokers, BDR was associated with a 48% higher risk (RR = 1.48, 95% CI = 1.01–2.20) of developing CAO.
Lead study author Ben Knox-Brown, of the National Heart and Lung Institute at the Imperial College London, and colleagues noted: "[BDR] is a risk factor for chronic airflow obstruction, an association that appears stronger in women than men."
The findings underscored the significance of BDR as a predictive factor for CAO, particularly among women and never-smokers. Spirometry remains a critical diagnostic tool for assessing long-term CAO risks. The investigators called for further research into the underlying mechanisms driving gender differences in disease progression.
No competing interests were disclosed in the study.
