Indoor Radon Decay Products Linked to Increased Cough and Phlegm in COPD Patients

A recent study highlights the association between exposure to radon decay products, measured as particle radioactivity (PR), and worsening respiratory symptoms in patients with chronic obstructive pulmonary disease (COPD).

The study involved 141 male former smokers with COPD who participated in up to four one-week seasonal assessments. Researchers measured indoor and ambient particulate matter (PM2.5) and black carbon (BC), alongside PR levels, using α-radiation activity on PM2.5 filters.

Respiratory symptoms, including cough, phlegm, and shortness of breath, were evaluated through the St. George’s Respiratory Questionnaire (SGRQ), which also assessed health-related quality of life (HRQL).

Results revealed that indoor radon decay products were significantly associated with increased cough (31.1% per interquartile range [IQR], 95% CI: 8.8%–57.8%) and suggestively associated with phlegm (13.0% per IQR, 95% CI: -2.5%–31.0%).

A modest increase in SGRQ symptom scores (1.2 units per IQR, 95% CI: -0.3–2.6) was also observed, though it did not reach statistical significance. These effects persisted after adjusting for indoor PM2.5 and BC.

The findings underscore the impact of indoor radon decay exposure on respiratory health in COPD patients, emphasizing the need for improved indoor air quality to mitigate symptom severity and enhance quality of life in this vulnerable population.