Loneliness, Social Isolation, and Effects on Cognitive Decline in Patients with Dementia: A Retrospective Cohort Study Using Natural Language Processing

The study aimed to compare cognitive trajectories between patients with reports of social isolation and loneliness and those without. Reports of social isolation, loneliness, and Montreal Cognitive Assessment (MoCA) scores were extracted from dementia patients’ medical records using Natural Language Processing models and analysed using mixed-effects models. Lonely patients (n = 382), compared to controls (n = 3912), showed an average MoCA score that was 0.83 points lower throughout the disease (p = 0.008). Socially isolated patients (n = 523) experienced a 0.21 MoCA points per year faster rate of cognitive decline in the six months before diagnosis (p = 0.029), but were comparable to controls before this period. This led to average MoCA scores that were 0.69 MoCA points lower at diagnosis (p = 0.011). Lower cognitive levels in lonely and socially isolated patients suggest that these factors may contribute to dementia progression.