A Multifaceted Intervention to Mitigate the Adverse Cardiovascular Effects of Air Pollution: A Feasibility Randomized Controlled Trial

Air pollution is associated with excess thrombotic and cardiovascular events. However, clinical outcomes trials evaluating interventions to mitigate such adverse events in patients with atherosclerotic cardiovascular diseases (ASCVD) are lacking. This is a single-center, open-label, feasibility randomized controlled trial (RCT) conducted in adult patients with documented ASCVD. Participants were randomized to a hybrid strategy consisting of an educational flashcard, educational cell phone text message alerts on polluted days to stay indoors, use KN95 masks if they need to go outside, and to consume citrus fruits on polluted days, versus usual care. The main objectives were to assess the feasibility of enrollment and adherence to and satisfaction with the hybrid strategy along with health-related quality of life and anxiety level. Between January 28, 2024, and February 18, 2024, 130 patients were screened, of whom 50 (38.5%) were randomized. During the study period, 12 polluted days occurred, and patients received a median of 8 ((IQR) 8 to 10) alerts. The majority adhered to all components on all polluted days, including full adherence for reading flashcards in 56%, avoiding outdoor activities in 52%, wearing KN-95 facemasks if they went out in 81.8%, and self-reported citrus fruit consumption in 84% of enrollees. The most participants in the intervention arm were satisfied with all components of the hybrid staretgy. Quality of life index and anxiety level remained unchanged for both groups during the 30-day follow-up. This pilot study shows the feasibility of recruitment to multifaceted strategy to mitigate the cardiovascular effects of air pollution with high adherence and satisfaction, thus supporting initiatives to design and conduct a large-scale RCT to validate and extend these findings.