Introduction: Aircraft noise is a concern for communities living near airports, but its impact on heart structure and function is unknown. Methods: Night-time (L night ) and weighted 24-hour day (L den ) aircraft noise levels were provided by the UK Civil Aviation Authority for 2011 (Fig.1). Health data came from UK Biobank (UKB) participants living near four UK major airports (Heathrow, Gatwick, Manchester, and Birmingham) who had cardiovascular magnetic resonance (CMR) imaging starting from 2014 and self-reported no hearing difficulties. Generalized linear models investigated the associations between aircraft noise exposure and CMR metrics (derived using a validated convolutional neural network to ensure consistent image segmentations), after adjustment for demographics, socio-economic, lifestyle, and environmental covariates. Mediation by cardiovascular (CV) risk factors was also explored. Downstream associations between CMR metrics and major adverse cardiac events (MACE) were tested in a separate prospective UKB subcohort (n=26,658) to understand the potential clinical impact of noise-associated heart remodeling. Results: Of 3,635 UKB participants included, 3% experienced higher aircraft noise L night (≥45decibels) and 8% higher L den (≥50decibels). Participants exposed to higher L night had 7% [95% confidence interval: 4–10%] higher left ventricular (LV) mass and 4% [2–5%] thicker LV walls with a normal septal:lateral wall thickness ratio (Fig.2 A1). This LV concentric remodeling is relevant since 7% higher LV mass associates with 32% higher odds of MACE. They also had worse LV myocardial dynamics (Fig.2 A2) (e.g., 8% [4–12%] lower global circumferential strain which associates with 37% higher odds of MACE). Overall, a hypothetical individual experiencing the typical CMR abnormalities associated with higher L night exposure may have 5-times higher odds of MACE. Body mass index and hypertension appeared to mediate 20-50% of the observed associations. Findings were similar in those exposed to higher L den (Fig.2 B1-2). Participants who did not move home during follow-up and were continuously exposed to higher aircraft noise levels had the worst CMR phenotype. Conclusion: Higher aircraft noise exposure associates with adverse LV remodeling, potentially due to noise increasing the risk of obesity and hypertension. Findings are consistent with the existing literature on aircraft noise and CV disease, and need to be considered by policymakers and the aviation industry.
Read full abstract