Spatial and temporal associations between physical establishment density and hearing difficulty across US counties

Hearing loss is a critical public health issue in the United States, affecting more than 15% of American adults. Existing studies have primarily focused on physiological and socioeconomic factors associated with hearing health. This study investigates the spatial and temporal associations between physical establishment density and hearing difficulty rates across US counties. Bivariate correlation analysis shows that counties with denser physical establishments generally exhibit lower hearing difficulty rates, and vice versa. Counties with lower hearing difficulty rates also tend to exhibit denser road networks, higher socioeconomic status, younger population structures, better insurance coverage, and higher educational attainment levels. After controlling for road density and other sociodemographic covariates in regression analyses, physical establishment density becomes positively associated with hearing difficulty rate. Our analyses indicate that road density largely drives this sign reversal and reflects broader infrastructure accessibility and urban service connectivity. We also identified hearing-health-risky physical establishments, representing environments potentially associated with elevated occupational or lifestyle-related noise exposure. Hearing-health-risky physical establishment density showed a stronger positive association with hearing difficulty rates than overall physical establishment density. Temporal clustering analysis further reveals that counties exhibiting increasing trends in hearing difficulty rates during 2012-2021 tended to have higher physical establishment density. Our findings suggest that counties characterized by denser built environments and better socioeconomic conditions currently exhibit lower hearing difficulty rates at the aggregate level, while urbanized environments may also be associated with growing long-term hearing-health risks. These findings provide implications for hearing-related urban planning, environmental noise management, and public health policy.