Cause or Effect?
The main problem with all the research conducted so far is that social impairment itself is typical of dementia. It’s one of the most common symptoms of the disease. People may feel less inclined to meet friends, visit family or interact with strangers when they have the disease or in the years leading up to it, even before symptoms of cognitive decline show themselves. That's because pathological changes in the brain take place over many years. To provide really good evidence that a lack of social engagement is a cause of dementia and not just linked to it, researchers would have to follow a group of initially healthy participants over several decades. So that's just what a team from University College London decided to do.A 28-Year Follow-Up Study
They used data from a study called Whitehall II, established between 1985 and 1988. It was collected from 10,228 London-based office staff (two-thirds men, one-third women), aged 35–55, working in 20 civil service departments. Between 1985 and 2013 each participant was asked six times how frequently they met with friends and relatives. Also, beginning in 1997, the cognitive abilities of the participants were tested on five separate occasions ending in 2016. These were tests of verbal fluency and short-term verbal memory. The researchers also assessed verbal and mathematical reasoning. In addition, the researchers examined the participants’ electronic health records to see if a diagnosis of dementia had ever been made. This continued until 2017. In conducting the analysis, the researchers took into account the participants’ age, gender, ethnicity, education, socio-economic status, employment and marital status, whether they smoked, how much alcohol they consumed, and their physical activity.Builds Cognitive Reserve
"We found that more frequent midlife social contact was associated with higher subsequent cognitive performance,” said the authors, “[and] that greater frequency of social contact at age 60 years was associated with lower risk of developing dementia." Seeing friends almost daily at age 60 provided a 12% reduction in the chances of developing dementia compared to those who saw only one or two friends every few months. Because the study was conducted over a period of almost 30 years, it strengthens the evidence that social engagement can protect people from dementia. Commenting on their findings, senior author Professor Gill Livingston said, "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." Her comments were supported by Tara Spires-Jones, a professor of neurodegeneration at the University of Edinburgh who was not involved in the study. "Learning new things builds connections between brain cells, and so does social contact,” wrote Prof. Spires-Jones. “The biology underlying this study is that the people who are socially active keep their brains better connected. If you have a better connected network in your brain, it can resist pathology for longer." As I said, it's time to get chatting.