SummaryThis comprehensive analysis aims to investigate the cross-sectional and longitudinal associations between annual exposure to transportation noise and various MASLD-related biomarkers and scores. This study will build on previous NAKO findings where annual transportation noise exposure was associated with hepatic fat content derived from magnetic resonance imaging. Therefore, we will use geocoded data on annual exposure to transportation noise linked to the residential addresses of NAKO participants. The outcomes of interest include liver enzymes and MASLD-related markers and scores, which will be used to determine hepatic steatosis. To assess the cross-sectional and longitudinal associations between noise exposure and MASLD-related outcomes, we will apply linear regression, logistic regression and mixed-effects models, respectively. Two exposure models will be employed to examine whether noise associations are independent of other environmental exposures such as air pollutants and surrounding greenness. Effect modification by inflammatory markers and sleep deprivation will be considered as in the association between noise exposure and MASLD. This study will provide the first evidence of a potential link between transportation noise and liver health in a large population-based sample, suggesting that environmental factors may contribute to the development of MASLD. Furthermore, given the growing prevalence of MASLD (25% globally), this research topic is highly pertinent, emphasizing the necessity for scientific investigation. As early detection and management of risk factors can reverse MASLD, population-level prevention approaches that mitigate noise could complement existing individual behavioral prevention and treatment approaches.

Keywords MASLD environment liver-enzymes longitudinal transportation-noise

InstitutionsHelmholtz Zentrum München, Heinrich-Heine-Universität Düsseldorf, Universität Halle-Wittenberg, Universitätsklinkum Halle, Radiologie Freiburg, Universitätsklinikum Freiburg