NEW population-based research across three continents suggests that chronic bronchitis is far more common in low- and middle-income countries (LMIC) than previously recognised, and is strongly linked to preventable environmental and lifestyle risk factors. The findings highlight an urgent need for earlier detection and targeted public health interventions to reduce long-term respiratory disability.
Chronic Bronchitis Affects Nearly One in Ten Adults
The study examined respiratory health in 9,664 adults aged 40 years and older living in Nepal, Peru, and Uganda. Researchers defined chronic bronchitis as a productive cough occurring several days per week for more than 4 weeks, a symptom profile that often precedes or accompanies COPD.
Overall, 9.7% of participants met the criteria for chronic bronchitis, and nearly a third of these individuals were also diagnosed with COPD. This reinforces growing evidence that chronic bronchitis may serve as an early warning sign for progressive lung disease, particularly in settings with high exposure to respiratory irritants.
Smoking, Biomass Exposure, and Poverty Drive Risk
Multiple modifiable risk factors were strongly associated with chronic bronchitis. Tobacco exposure remained a major contributor, with risk rising steadily alongside cumulative pack-years of smoking. However, the study also emphasises the role of second-hand smoke, which increased risk by nearly 50%.
Indoor biomass fuel exposure, from cooking or heating with wood, charcoal, or dung, was another key driver, reflecting ongoing energy poverty in many low-resource settings. Participants in the lowest socioeconomic quartile were also significantly more likely to report chronic bronchitis, highlighting how structural inequalities shape respiratory health.
Past Lung Disease Raises Long-Term Vulnerability
Individuals with a history of tuberculosis or asthma were at particularly high risk. Prior asthma more than doubled the likelihood of chronic bronchitis, while past tuberculosis infection increased risk by 45%. A family history of chronic respiratory disease further amplified vulnerability, suggesting overlapping genetic and environmental influences.
Worse Symptoms and Higher Hospitalisation Rates
Beyond prevalence, chronic bronchitis was linked to substantially poorer health outcomes. Affected participants reported more breathlessness, worse overall respiratory health scores, and significantly higher rates of hospitalisation. These impacts point to a considerable burden on both individuals and already-stretched healthcare systems.
Why Addressing Chronic Bronchitis Matters
Researchers conclude that chronic bronchitis is not a benign condition, especially in LMICs. Because many risk factors, such as indoor air pollution and second-hand smoke, are preventable, targeted interventions could meaningfully reduce disease burden and improve quality of life.
Early recognition and prevention strategies, the authors suggest, may also help slow progression to COPD, offering a critical window for public health action.
Reference
Robertson NM et al; Global Excellence in COPD outcomes (GECo) Study Investigators. A multi-country cohort study evaluating the prevalence, risk factors, lung function and clinical outcomes of chronic bronchitis in low- and middle-income countries. Eur Respir J. 2025; DOI:10.1183/13993003.01435-2025.
