079Environmental Approaches to Cognitive Ageing: An Investigation of the Role of Population Density and Disability

Abstract

Background: Understanding how increasing urbanisation affects health inequalities with ageing has gained growing interest [1], but the synergistic influence of environmental and individual factors on cognitive ageing is yet unclear [2]. The present study investigated the impact on cognitive health of living in more or less densely populated areas and having or not a disability. Method(s): Using data from a large cohort study and the Census, we explored crosssectional variations in global cognition, memory, and executive functions for 4,127 Irish people aged 50+ based on the level of population density of the electoral division of residence (approximately 20km2) and the presence of disabilities (ADL and/or IADL). Regression models controlled for socio-demographic, health and lifestyle covariates. Result(s): Overall higher cognitive scores were found in more rather than less populated electoral divisions (10+ vs. <10 persons per hectare) after controlling for covariates. However, participants with disabilities living in the most densely populated areas had the poorest performance in terms of MoCA (p = 0.005), immediate recall (p = 0.02) and executive functions (p = 0.009). Demographic or lifestyle circumstances did not affect these results. Conclusion(s): While highly populated areas present more opportunities for mental stimulation which can benefit cognitive health, having a disability may increase the individual's susceptibility to environmental stressors (e.g. crowding), with a negative impact on cognition. The findings highlight the importance of considering how the lived environment fits individual resources or limitations to better understand geographical variations in cognitive ageing.