Sensory impairment, epigenetic ageing, and later-life functional decline and mortality in older adults.

Sensory impairment (SI) and accelerated epigenetic aging are both linked to later-life vulnerability, yet their joint value for risk stratification remains poorly understood. We investigated whether the co-occurrence of sensory deficits and accelerated epigenetic aging identifies older adults at heightened risk of functional decline and mortality. We analyzed data from 2,395 participants in the 2016 wave of the Health and Retirement Study with valid DNA methylation (DNAm) and sensory data. Epigenetic aging was assessed using GrimAgeAccel and methylation Pace of Aging (MPOA). Sensory phenotypes were categorized as no impairment, hearing impairment only, vision impairment only, and dual sensory impairment (DSI). Primary outcomes included subsequent mobility worsening, ADL/IADL worsening, and all-cause mortality. Cross-sectionally, vision impairment only and DSI were associated with higher GrimAgeAccel in demographic- and socioeconomic-adjusted models, but these associations were attenuated after further adjustment for lifestyle and health burden. In joint analyses, participants with both sensory impairment and high GrimAgeAccel had the highest risks of mobility worsening (OR = 1.91, 95% CI 1.35-2.72), ADL/IADL worsening (OR = 2.85, 95% CI 1.96-4.14), and mortality (HR = 5.77, 95% CI 3.60-9.23), compared with the low-risk reference group. These associations remained evident in participants who were functionally intact at baseline. Sensory impairment and accelerated GrimAgeAccel jointly identified older adults at elevated risk of subsequent functional decline and mortality. These findings support a risk-stratification framework integrating clinically accessible sensory assessment with DNAm-based biological ageing measures, although formal evidence for biological interaction was limited.