Reply to Alexis: Controlled Chamber Studies Showed Protective Effect of Nonsteroidal Antiinflammatory Drugs against Ozone Exposure: The Stage Was Set for Broader Epidemiologic Investigation.

From the Authors:

We appreciate the valuable opinion shared by Dr. Neil E. Alexis on our article on the modifying effect by nonsteroidal antiinflammatory drugs (NSAIDs) on the association of short-term air pollution with lung function (1). We highly agree with him that similar modifying effects of NSAIDs had been previously described by controlled human chamber exposure studies with ozone. Chamber exposure studies have great advantages in that they allow to control both the exposure and the NSAID treatment. Yet, they are typically small in scale and may benefit from investigations that generalize their results in population studies. To the best of our knowledge, our study is the first larger-scale study on the modifying effects of NSAIDs among elderly adults (>55 yr-old).

To confirm our statement, we searched PubMed again for articles published up to February 18, 2020 that investigated the effect of NSAIDs on lung function decline in response to air pollution. We used the search terms “nonsteroidal antiinflammatory agents”, “aspirin”, “lung function”, “air pollution”, “PM2.5”, “black carbon”, “ozone”, “particle number”, “carbon monoxide”, “sulfur dioxide”, and “nitrogen dioxide” in various combinations. We did not identify any population-based studies of older adults. Hence, together with the controlled human studies from Dr. Alexis’ (2) and other teams, our cohort findings are important to support the hypothesis that NSAIDs treatment may protect against the adverse effects of air pollution on lung function. The evidence to date indicates the need for further validations based on well-powered randomized controlled clinical trials on NSAIDs in elderly adults.

We welcome continued dialogue and collaborations with pulmonologists, clinical research specialists, epidemiologists, and environmental health scientists to help elucidate the roles of NSAIDs in the prevention of air pollution–related pulmonary outcomes. Collaboration among all relevant parties will be instrumental in the potential implementations of NSAIDs and other antiinflammatory agents for environmental respiratory health research.