Digital Isolation and Dementia Risk in Older Adults: Longitudinal Cohort Study

Abstract

Background: Dementia poses a significant global health challenge, characterized by progressive cognitive decline and functional impairment. With the aging global population, dementia prevalence is projected to surge, reaching an estimated 153 million cases by 2050. While the impact of traditional social isolation on dementia risk has been extensively studied, the influence of digital isolation, a phenomenon unique to the digital age, remains underexplored. Objective: This study aimed to investigate the association between digital isolation and dementia risk among older adults, hypothesizing that higher levels of digital isolation significantly increase the risk of developing dementia. Methods: We conducted a longitudinal cohort study using data from the National Health and Aging Trends Study (NHATS), analyzing 8189 participants aged 65 years and older from the 3rd (2013) to the 12th wave (2022). Digital isolation was quantified using a composite digital isolation index, derived from participants’ usage of digital devices, electronic communication, internet access, and engagement in online activities. Participants were stratified into low isolation and moderate to high isolation groups. Dementia incidence was assessed using cognitive tests and proxy reports. Cox proportional hazards models were used to estimate the association between digital isolation and dementia risk, adjusting for potential confounders including sociodemographic factors, baseline health conditions, and lifestyle variables. Results: The moderate to high isolation group demonstrated a significantly elevated risk of dementia compared with the low isolation group. In the discovery cohort, the adjusted hazard ratio (HR) was 1.22 (95% CI 1.01-1.47, P=.04), while the validation cohort showed an HR of 1.62 (95% CI 1.27-2.08, P