Occupational noise exposure and long-term cardiovascular mortality in the united states: a 20-year nationally representative cohort study

Background Occupational noise (ONoise) is a pervasive yet understudied cardiovascular risk factor. Prior research has examined modeled nighttime environmental noise, whereas the cardiovascular (CV) impact of perceived occupational noise, capturing both exposure intensity and individual sensitivity, remains largely unknown. Perceived noise may be biologically relevant, as annoyance and subjective disturbance can trigger sustained autonomic and inflammatory activation independent of measured sound levels. Purpose To assess the association between ONoise and long-term cardiovascular mortality (CVM) in a nationally representative U.S. cohort, and to evaluate differences across sociodemographic groups and baseline CV risk strata. Methods We analyzed working adults from NHANES 1999–2004 linked to the National Death Index through 2019. ONoise exposure was self-reported and classified as exposed vs unexposed. CVM was defined as deaths from heart disease or cerebrovascular causes. Survey-weighted Cox proportional hazards models adjusted for demographic, socioeconomic, lifestyle, and clinical factors. NHANES sampling weights and design variables ensured national representativeness. Baseline CV risk was quantified using the PREVENT Equations, with subgroup analyses performed across demographic and risk strata. Results Among 5,843 participants (median age 39 years; 55% male; 10% Black), representing 303 million U.S. adults, 34.5% reported ONoise exposure. Over a median 20-year follow-up, 124 CV deaths occurred. In fully adjusted models, ONoise associated with higher risk of CVM (HR 2.12; 95% CI 1.31–3.44; p=0.002; Fig. 1A) and heart disease mortality (HR 2.26; 95% CI 1.38–3.69; p=0.001; Fig. 1B). In subgroup analyses (Fig. 2), associations were evident among adults ≥45 years (HR 1.83; p=0.01), males (HR 2.01; p=0.02), Non-Hispanic Whites, and those with ≤high school education (HR 1.86; p=0.01). Elevated risks were also observed among both insured and uninsured individuals and across baseline risk strata. Notably, risk estimates were strongest among young adults <45 years (HR 3.71; p-interaction=0.01), Hispanics (HR 4.46; p-interaction=0.01), and those with poverty-income ratio <200% (HR 3.45; p-interaction=0.10). Similar patterns were observed for heart disease mortality and after excluding deaths within the first one or two years of follow-up. Conclusions In this nationally representative cohort, occupational noise exposure was independently associated with higher long-term CVM risk, particularly heart disease deaths. Associations were strongest among young adults, Hispanics, and individuals with lower socioeconomic status or limited health care access. These findings highlight ONoise, especially as perceived and experienced by workers, as an overlooked CV risk factor and underscore the need to integrate occupational environmental exposures into CV prevention efforts.