A new study, published in the journal PLoS Medicine, suggests that more frequent social contact during early and midlife may build cognitive reserve, which is maintained and delays or prevents the clinical expression of dementia.
Being more socially active in your 50-60s predicts a lower risk of developing dementia later on. Image credit: Lee Chandler.
“Dementia is a major global health challenge, with one million people expected to have dementia in the UK by 2021, but we also know that one in three cases are potentially preventable,” said Dr. Andrew Sommerlad, a researcher at University College London and the lead author on the study.
“Here we’ve found that social contact, in middle age and late life, appears to lower the risk of dementia. This finding could feed into strategies to reduce everyone’s risk of developing dementia, adding yet another reason to promote connected communities and find ways to reduce isolation and loneliness.”
Dr. Sommerlad and colleagues used data from the Whitehall II study, tracking 10,228 participants who had been asked on six occasions between 1985 and 2013 about their frequency of social contact with friends and relatives.
The same participants also completed cognitive testing from 1997 onwards, and the scientists referred to the study subjects’ electronic health records up until 2017 to see if they were ever diagnosed with dementia.
The authors focused on the relationships between social contact at age 50, 60 and 70, and subsequent incidence of dementia, and whether social contact was linked to cognitive decline, after accounting for other factors such as education, employment, marital status and socioeconomic status.
They found that increased social contact at age 60 is associated with a significantly lower risk of developing dementia later in life.
The analysis showed that someone who saw friends almost daily at age 60 was 12% less likely to develop dementia than someone who only saw one or two friends every few months.
The researchers found similarly strong associations between social contact at ages 50 and 70 and subsequent dementia.
“While those associations did not reach statistical significance, social contact at any age may well have a similar impact on reducing dementia risk,” they said.
“Social contact in mid to late life was similarly correlated with general cognitive measures.”
There are a few explanations for how social contact could reduce dementia risk, according to the team.
“People who are socially engaged are exercising cognitive skills such as memory and language, which may help them to develop cognitive reserve — while it may not stop their brains from changing, cognitive reserve could help people cope better with the effects of age and delay any symptoms of dementia,” said University College London’s Professor Gill Livingston, senior author of the study.
“Spending more time with friends could also be good for mental wellbeing, and may correlate with being physically active, both of which can also reduce the risk of developing dementia.”
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A. Sommerlad et al. 2019. Association of social contact with dementia and cognition: 28-year follow-up of the Whitehall II cohort study. PLoS Med 16 (8): e1002862; doi: 10.1371/journal.pmed.1002862
