Beyond the Years : Exploring the role of sensory functions and cognitive abilities in shaping the patterns of old age disabilities and successful aging in an aging population in Sweden and Denmark: An epidemiological perspective of disability

Abstract: AIMS: This research project aims to review the lay perspectives of older adults 75 and above regarding successful aging, as well as estimate the prevalence of sensory difficulties by different subgroups, explore the role of cognition and sensory function in explaining decreasing disability trends over time in Sweden and Denmark and, lastly, longitudinally examine the sensory-cognitive relation in older adults. METHODS: For Study I, a systematic review was conducted, while for Study II the prevalence of sensory functions was estimated. For Study III, the Karlson Holm Breen method was used, whereas Study IV applied a cross-lagged panel model. RESULTS: This research indicates that younger and older adults have different definitions of successful aging, with themes of life, death, and environmental/system influences being important for those aged 75 and above (Study I). Study II shows that the prevalence of sensory difficulties in old age varies among subgroups, and Study III reveals a decreasing prevalence of disability in Sweden and Denmark, attributed to cognitive function, education, reading ability, and hearing ability. Finally, Study IV highlights a reciprocal relationship between sensory functions and cognition among older adults, with better cognitive function associated with better hearing and vision scores over time. DISCUSSION: This research underlines the need for policymakers to cater to the diverse needs of different generations based on gender differences, environmental factors, and access to healthcare and social services. Study II reveals a higher prevalence of sensory difficulties among certain subgroups, which could be targeted by specific interventions. Study III and IV indicate that preserving good sensory functions may mitigate cognitive decline, with interventions including vision and hearing aids and surgeries potentially delaying cognitive decline.