Age Effects and Associations among Cognitive, Language, and Swallowing Functions in Community-Dwelling Older Adults

Objectives: This study comprehensively examined 1) age-related changes in cognitive, language, and swallowing functions by classifying participants into young-old (55-69 years), middle-old (70-79 years), and oldest-old (≥80 years) groups, and 2) the associations among cognitive, language, and swallowing functions in community-dwelling elderly.Methods: Cognitive function was assessed using subtests of the Seoul Neuropsychological Screening Battery-II (SNSB-II). Language function was evaluated using the Paradise Korean Western Aphasia Battery-Revised (K-WAB-R), the Korean Boston Naming Test (K-BNT), and the Controlled Oral Word Association Test (COWAT). Swallowing function was assessed using the self-report sections of the Swallowing Monitoring and Assessment Protocol (SMAP). All scores were standardized using Z-scores. Group differences were analyzed using analysis of covariance (ANCOVA), controlling for years of education, and inter-domain associations were examined using multiple linear regression analyses.Results: In cognition, attention and memory declined significantly with age after controlling for years of education, whereas working memory and frontal/executive functions did not show significant differences across age groups. In language, auditory comprehension and naming showed significant age effects. In swallowing, the oldest-old group showed the lowest mean swallowing function; however, a significant group difference was observed only between the middle- old and oldest-old groups. Regression analyses revealed significant associations between the cognitive and language domains, whereas swallowing function showed minimal associations with other domains.Conclusion: These findings provide a basis for early detection of cognitive, language, and swallowing decline in community-dwelling older adults, as well as for establishing priorities for domain-specific interventions.