Mediating the relationship between loneliness and cognitive function: the role of depressive and anxiety symptoms

Abstract

Objective: To evaluate the relationship between loneliness and cognitive functioning, and whether depressive and anxiety symptoms have intermediate roles therein.

Methods: Information about 7,433 participants of the Irish Longitudinal Study on Ageing (a prospective, representative cohort study), aged over 50, was collected at three time-points two years apart, and analysed using Structural Equation Modelling to assess whether depressive and anxiety symptoms mediate the relationship between loneliness and cognitive functioning. Cognitive functioning was measured as a latent factor, with four indicators: measures of immediate and delayed word recall, verbal fluency, and a global measure (the MMSE). Loneliness was measured using the UCLA Loneliness scale, depressive symptoms using the CES-D-ML scale, and anxiety symptoms using the HADS-A scale.

Results: Loneliness at time-point 1 predicted cognitive functioning at time-point 3, β = −0.103, p < 0.001, and depressive (β = 0.426, p < 0.001) and anxiety (β = 0.410, p < 0.001) symptoms at time-point 2. Depressive (β = −0.020, p = 0.001) but not anxiety (β = −0.000, p = 0.658) symptoms mediated the relationship between loneliness and cognitive functioning, total effect: β = −0.123, p < 0.001.

Conclusion: The relationship between loneliness and cognitive functioning is in part explained by its relationship with depressive symptoms. Statistically, the mediation model helps us understand possible mechanisms through which loneliness impacts cognitive functioning. Results have implications for cognitive functioning interventions for older adults, and imply that loneliness is also a worthwhile target for intervention.

Keywords:

• Ageing
• cognitive function
• mental health
• structural equation modelling

Acknowledgments

We wish to thank the staff and participants of TILDA for their role in this study. The project has been designed and implemented by the TILDA Study Team © Department of Health and Children. Copyright and all other intellectual property rights relating to the data are vested in TILDA.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Funding was received by Joanna McHugh Power in the form of a Leadership in Ageing Research Fellowship grant (from the Centre of Ageing Research and Development in Ireland, now the Institute of Public Health). The TILDA data have been co-funded by the Government of Ireland through the Office of the Minister for Health and Children, by Atlantic Philanthropies, and by Irish Life; have been collected under the Statistics Act, 1993, of the Central Statistics Office.