The long‐term impact of loneliness and social isolation on depression and anxiety in memory clinic attendees and their care partners: A longitudinal actor–partner interdependence model

Abstract Introduction This study examined the long‐term influence of loneliness and social isolation on mental health outcomes in memory assessment service (MAS) attendees and their care partners, with a focus on interdependence and bidirectionality. Methods Longitudinal data from 95 clinic attendees with cognitive impairment, and their care partners (dyads), from four MAS in the North of England were analyzed. We applied the actor–partner interdependence model, seeking associations within the dyad. At baseline and 12‐month follow‐up, clinic attendees and care partners completed measures of loneliness and social isolation, depression, and anxiety. Results Social isolation at baseline was more prevalent in care partners compared to MAS attendees. Social isolation in MAS attendees was associated with higher anxiety symptoms (β = 0.28, 95% confidence intervals [CIs] = 0.11 to 0.45) in themselves at 12 months. We found significant positive actor and partner effects of loneliness on depression (actor effect: β = 0.36, 95% CIs = 0.19 to 0.53; partner effect: β = 0.23, 95% CIs = 0.06 to 0.40) and anxiety (actor effect: β = 0.39, 95% CIs = 0.23 to 0.55; partner effect: β = 0.22, 95% CIs = 0.05 to 0.39) among MAS attendees 1 year later. Loneliness scores of the care partners have a significant and positive association with depressive (β = 0.36, 95% CIs = 0.19 to 0.53) and anxiety symptoms (β = 0.32, 95% CIs = 0.22 to 0.55) in themselves at 12 months. Discussion Loneliness and social isolation in MAS clinic attendees had a downstream effect on their own and their care partners’ mental health. This highlights the importance of including care partners in assessments of mental health and social connectedness and expanding the remit of social prescribing in the MAS context.