Co-occurring trajectories of auditory, cognitive, and physical decline in older adults: A longitudinal latent class analysis

BACKGROUND: Auditory, cognitive, and physical capacity are key domains of functioning, recently referred to as "intrinsic capacity" (IC), in older adults. While growing evidence suggests interrelated declines across these domains, few studies have concurrently examined their longitudinal trajectories. METHODS: This study used Latent Growth Mixture Modeling (LGMM) to identify patterns of decline in hearing, cognition, and physical function over three years among 326 older adults (aged≥60) in a health screening cohort in Hangzhou, China, and further explored the interrelationships among these three functions. RESULTS: After a three-year follow-up assessment, three distinct trajectories were identified for both Pure-Tone Average (PTA) and Mini-Cog scores using LGMM, and four trajectories were identified for the Short Physical Performance Battery (SPPB). Multidomain analysis showed that hearing loss was significantly associated with both cognitive function (Cramér's V = 0.317) and physical function (Cramér's V = 0.232; both p < 0.001). The three-dimensional trajectories revealed clear cluster differentiation, with only 14.7% (n = 15) of individuals with no hearing loss exhibiting poor cognitive and physical function, compared to 50.8% (n = 93) among those with moderate hearing loss. CONCLUSIONS: These findings suggest that individuals with greater hearing loss are more likely to cluster into subtypes characterized by significant declines in both cognitive and physical function. The results support a pattern of synergistic deterioration across auditory, cognitive, and physical domains in older adults, indicating that early identification and intervention for hearing loss may help delay declines in cognitive and physical function.