Association of Noise Exposure, Perceived Noise Impact, and BMI on Nonalcoholic Fatty Liver Disease Among Chinese Seafarers: Nationwide Population-Based Survey.

Background: Nonalcoholic fatty liver disease (NAFLD) is a global public health challenge, yet its relationship between occupational noise exposure and perceived noise impact remains unclear. Objective: We characterized maritime noise exposure patterns and examined the associations of noise exposure, perceived noise impact, and BMI with NAFLD among seafarers. Methods: A population-based survey was conducted from March to May 2024 through the China Shipowners' Association. Participants completed a structured online questionnaire. Noise exposure was assessed via self-report, and NAFLD presence was determined by self-reported physician diagnoses based on the 2018 updated NAFLD guidelines. Results: A total of 8143 male seafarers was included, with an overall NAFLD prevalence of 18.5% (n=1503). The prevalence was significantly higher among seafarers with a BMI of 24.0 kg/m² or above (25.9%, n=1261), chronic noise exposure (19.4%, n=1293), and higher perceived noise impact (slightly: 16.9%, n=589; moderate: 19.1%, n=359; significant: 22.5%, n=511). Among seafarers with a BMI of 24.0 kg/m² or above, chronic noise exposure and higher perceived noise impact were significantly associated with an elevated risk of NAFLD. After full adjustment, the combined association of chronic noise exposure and higher perceived noise impact remained significantly associated with increased NAFLD risk, with consistent patterns observed across both workplace and rest area settings. A significant interaction was also observed between rest-area noise exposure and perceived noise impact in this BMI subgroup. Conclusions: Noise exposure, perceived noise impact, and BMI were significantly associated with NAFLD among seafarers. These findings highlight the importance of optimizing occupational health benefits, especially among those with metabolic disorders.