New approach to preventing social isolation

Common public health strategies that focus only on particularly isolated people might be missing out on a lot of the preventive potential of greater social integration

Visual representation of factors affecting health and cognition: social structural conditions, networks, psychosocial mechanisms, and pathways, with icons for each category.

Visual representation of factors affecting health and cognition: social structural conditions, networks, psychosocial mechanisms, and pathways, with icons for each category.

To the point

• Social Isolation: Weak social relationships pose a significant public health problem, affecting brain health and mental well-being.
• Research Findings: A study involving over 10,000 participants revealed that more social contacts correlate with better cognitive abilities and mental health, including larger hippocampi linked to memory.
• New Strategies: Current public health approaches focusing on isolated individuals may overlook broader societal interventions that could enhance social integration and prevent issues like dementia and depression.
• Population-Level Interventions: Experts suggest that promoting social connections at a community level is more effective than individual-focused strategies for improving mental health outcomes.

Weak social relationships are an urgent public health problem, but there is a severe lack of sound knowledge about which strategy should be pursued in preventive measures. In their analysis, the scientists led by Laurenz Lammer tested a novel approach and used so-called mixed additive models to analyze the relationships between social isolation and its effects on brain health, cognitive abilities and mental health in a population-based sample. "We examined a total of over 10,000 participants (average age 58, 53 percent women) at the start of the study and over 5,500 participants (average age 64, 53 percent women) at the follow-up examination after about six years. They underwent brain measurements using 3Tesla MRIs, we assessed their cognitive functions with extensive neuropsychological tests, and measured social isolation and mental health using established questionnaires.

Beige building facade featuring four windows. A cat sits on the ledge of an open window, while other windows have shutters. A woman is looking out of a window.

Beige building facade featuring four windows. A cat sits on the ledge of an open window, while other windows have shutters. A woman is looking out of a window.

"We focused primarily on depression and anxiety disorders," explains the study's lead author, Laurenz Lammer. "A linear correlation would say, for example, that the fewer social contacts people have, the more frequently they experience depressive symptoms, and the more social contacts they have, the better. Another categorical approach, which is quite common in medicine, would say that whether you have two good social contacts or three makes no big difference – once you fall below a critical point, the curve for depression rises steeply. We have now used a special statistical model to see what the data tells us about the shape of the relationship. We found that the number of social contacts consistently allows for significant predictions about brain health, cognitive abilities and mental health. For example, we found linear correlations: the more social contacts people had, the larger their hippocampi, i.e. their memory centres in the brain. Overall, we found consistently positive effects of social contacts on quality of life."

What does this mean for new public health strategies? Laurenz Lammer offers his perspective: "Politicians are already attempting to combat social isolation and its effects – we asked ourselves how we should go about this and whether we could combine established theories and data to answer this question. It appears that with the current strategy of focusing on isolated individuals, we are missing out on much of the potential that we could achieve with societal approaches. The current focus on individual-level interventions against social isolation is probably not optimal, at least for the prevention of dementia, cognitive decline, anxiety and depression. On the contrary, we point to population-level interventions that aim to promote social connections throughout society as more promising approaches to prevention. We could consider how we can change structures in our cities or rural areas to promote social contact. What cultural factors could we promote to encourage more interaction? How can we design neighbourhoods so that people feel more socially integrated?"