Exploring the Biopsychosocial Risk Factors for Dementia in People Ageing with Down Syndrome

Abstract

People ageing with Down syndrome are at much higher risk of developing dementia compared to the general population. The Lancet Model of brain health (Livingston et al., 2020) has not yet been tested for its applicability in this population. The aim of this study is to explore the relative influence of identified risk factors on dementia outcomes in a representative sample of an Irish population ageing with Down syndrome. Data gathered from the four waves of IDS-TILDA were used for longitudinal risk modelling. IDS-TILDA is an Irish nationally representative longitudinal study that collects information on a variety of biopsychosocial indicators in people ageing with intellectual disability. Binomial logistic regression analysis was used to investigate the predictive relationship between biopsychosocial risk factors and dementia outcomes over a period of 15 years. Dementia prevalence in the sample of 150 people with Down syndrome increased from 10.7% in Wave 1 to 44% by Wave 4. Longitudinal changes in cognitive functioning are associated with type of living situation and social isolation, with physical inactivity another variable of potential interest. General population risk factors such as hypertension, smoking, frequent alcohol use are not as relevant for this population. Findings from this exploratory modelling provide an initial framework to assess the relative influence of various biopsychosocial indicators on dementia outcomes in people ageing with Down syndrome. Development of an evidence-based framework of risk factors will support targeted interventions to improve the brain health of those with Down syndrome across the life span.