Social isolation was found to be an independent risk factor for dementia.
According to the research, social isolation is a definite risk factor for dementia since it is directly connected to alterations in the brain regions responsible for memory.
Researchers from the Universities of Warwick, Cambridge, and Fudan University analyzed neuroimaging data from more than 30,000 adults in the UK Biobank data set to examine how social isolation and loneliness were connected to eventual dementia. The gray matter volumes of the parts of the brain responsible for memory and learning were shown to be lower in socially isolated people.
The findings of the study were recently published in the journal Neurology.
The researchers employed modeling tools to look at the relative correlations between social isolation and loneliness and incident all-cause dementia using data from the UK Biobank, a large longitudinal cohort. After taking into account a number of risk variables, such as socioeconomic status, chronic disease, lifestyle choices, depression, and APOE genotype, it was shown that social isolation was associated with a 26% higher risk of dementia.
Loneliness was also linked to later dementia, although not after controlling for depression, which accounted for 75% of the connection between loneliness and dementia. Therefore, in contrast to the subjective experience of loneliness, objective social isolation is an independent risk factor for developing dementia later in life. The impact was more noticeable in those over 60, according to further subgroup analyses.
Professor Edmund Rolls, a neuroscientist from the University of Warwick Department of Computer Science, says, “There is a difference between social isolation, which is an objective state of low social connections, and loneliness, which is subjectively perceived social isolation. Both have risks to health but, using the extensive multi-modal data set from the UK Biobank, and working in a multidisciplinary way linking computational sciences and neuroscience, we have been able to show that it is social isolation, rather than the feeling of loneliness, which is an independent risk factor for later dementia. This means it can be used as a predictor or biomarker for dementia in the UK.”
He continues, “With the growing prevalence of social isolation and loneliness over the past decades, this has been a serious yet underappreciated public health problem. Now, in the shadow of the COVID-19 pandemic, there are implications for social relationship interventions and care – particularly in the older population.”
Professor Jianfeng Feng, from the University of Warwick Department of Computer Science, states, “We highlight the importance of an environmental method of reducing the risk of dementia in older adults through ensuring that they are not socially isolated. During any future pandemic lockdowns, it is important that individuals, especially older adults, do not experience social isolation.”
Professor Barbara J Sahakian, of the University of Cambridge Department of Psychiatry, says, “Now that we know the risk to brain health and dementia of social isolation, it is important that the government and communities take action to ensure that older individuals have communication and interactions with others on a regular basis.”
Reference: “Associations of Social Isolation and Loneliness With Later Dementia” by Chun Shen, Edmund T. Rolls, Wei Cheng, Jujiao Kang, Guiying Dong, Chao Xie, Xing-Ming Zhao, Barbara J. Sahakian and Jianfeng Feng, 8 June 2022, Neurology.