Mapping the network structure of dementia and its associated factors among older adults in Singapore: evidence from two national cross-sectional studies.

BACKGROUND: Dementia arises from the interplay of multiple sociodemographic, behavioural, physical, and psychosocial factors that often coexist and interact in later life. Traditional epidemiological studies have typically examined these factors in isolation, overlooking their complex interrelations. Network analysis provides an integrative framework to visualise and quantify these interconnections, offering insights into how dementia and its associated factors coexist within a broader system. METHODS: Data were drawn from two nationally representative cross-sectional surveys of older adults aged ≥60 years in Singapore: the Well-being of the Singapore Elderly (WiSE) 2023 study (n=2010) and the WiSE 2013 study (n=2565). Dementia was assessed using the 10/66 diagnostic criteria. Variables included factors identified by the Lancet Commission on Dementia Prevention, Intervention, and Care, and established indices including the Lifestyle for BRAin health (LIBRA), Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE), Australian National University Alzheimer's Disease Risk Index (ANU-ADRI), and World Health Organization (WHO) guidelines. Network structure was estimated using mixed graphical models. Sensitivity analyses were conducted to assess the robustness of the network. RESULTS: Across both surveys, dementia showed the strongest conditional associations with age, educational attainment, employment status, being physically active, walking frequency, stroke, daytime sleepiness, and difficulty maintaining friendships. The overall network structures were comparable in the two surveys, indicating stable interconnections among demographic, behavioural, and social domains. Majority of these interconnections were also not found to vary by gender and ethnicity. CONCLUSIONS: This study highlights the complex web of interrelations linking dementia with social, behavioural, and health-related factors in later life. Rather than implying causal direction, these findings illustrate how multiple factors cluster and coexist within older adults' lives. These interconnections may inform the design of holistic strategies that integrate employment opportunities, physical activity promotion, social participation, sleep health, and cerebrovascular prevention into comprehensive dementia prevention and care frameworks.