Why Is Social Isolation Among Older Adults Associated with Depressive Symptoms? The Mediating Role of Out-of-Home Physical Activity

• Published in: International journal of behavioral medicine Vol. 25; no. 6; pp. 649 - 657
• Main Authors: Herbolsheimer, Florian, Ungar, Nadine, Peter, Richard
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2018; Springer Nature B.V
• Subjects: Aged; Aged, 80 and over; Anxiety; Depression - psychology; Exercise; Exercise - psychology; Family Medicine; Female; Friends; General Practice; Germany; Health Psychology; Humans; Longitudinal Studies; Male; Medicine; Medicine & Public Health; Mental depression; Mental disorders; Mental Health; Middle Aged; Older people; Physical activity; Social interactions; Social isolation; Social Isolation - psychology; Social networks; Social organization; Germany; Depression; Longitudinal; Physical activity; Social isolation; Accelerometry
• ISSN: 1070-5503; 1532-7558
• DOI: 10.1007/s12529-018-9752-x

Background Social networks are known to be a key factor associated with late-life depression. However, there is limited knowledge about the pathways linking social isolation to mental health. It has been proposed that health-related behaviors such as physical activity represent one pathway. This study examines the way out-of-home physical activity mediates between social isolation and depressive symptoms in older adults. Methods A subsample of 334 older adults from the ActiFE Ulm study, Germany, was randomly selected. Older adults ( M  = 72.6 years; 60.8% male) were interviewed at baseline and 3 years later. Depressive symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS). Social isolation was measured using the Lubben Social Network Scale (LSNS-6). Physical activity was measured by an accelerometer (activPAL) over 1 week. To identify out-of-home physical activity, a contemporary physical activity diary classified out-of-home physical activity. Results A cross-lagged structural equation model supported an indirect effect ( β  = .014, 95% CI .002 to .039) which means that being socially isolated was associated with lower levels of out-of-home physical activity, and this predicted more depressive symptoms after 3 years. However, no direct relationship was observed between social isolation from friends and neighbors at the baseline and depressive symptoms 3 years later. Conclusions Utilizing a longitudinal study design and accounting for reverse causality, this study extends prior work linking social isolation to depression by showing that a variety of neighbor and friendship ties are linked to fewer depressive symptoms by providing occasions for out-of-home physical activity.