The Effect of Temporal Persistence of Loneliness on Dementia: A Longitudinal Analysis From the Hunter Community Study

Loneliness is common and becoming a public health concern. Although there is the clear evidence of the variable effect of temporal differences in loneliness (transient/situational and persistent/chronic) on health, their effect on dementia risk is unclear. This study aims to assess the effect of transient/situational and persistent/chronic loneliness on dementia risk.

Participants aged 55 years and older from the Hunter Community Study were recruited. Loneliness was measured using a single item measure. Dementia was defined as per International Classification of Disease-10 (ICD 10) codes. The Fine-Gray subdistribution hazard model was performed to calculate dementia risk.

Of 1968 total participants with mean age of 66 years, (3%) 57 developed dementia and (7%) 135 died over the mean follow up of 10 years. Both persistent/chronic and transient/situational loneliness significantly increased the risk of all cause dementia in adjusted models (HR 2.74, 95% CI 1.11-6.88, p 0.03 and HR 2.35, 95% CI 1.21-4.55, p 0.01 respectively) with mean time to event of 9.7 years. Feeling lonely below the age of 70 years elevated the risk of dementia in later life (HR 4.01, 95% CI 1.40-11.50, p 0.01).

Loneliness (both persistent/chronic and transient/situational) was associated with increased risk of all cause dementia, especially if loneliness was experienced before the age of 70 years. These results suggest that promoting coping strategies for loneliness especially in persons 70 years and younger may play a role in preventing dementia.