Experiencing feelings of loneliness three or more times a week may increase the risk of developing dementia later in life, according to a recent study in the journal Neurology.
The study showed that individuals experiencing loneliness, who were otherwise at lower risk of dementia due to genetic risk factors and age, had a threefold higher risk of developing dementia.
The study’s first author Dr. Joel Salinas, a neurologist at New York University Langone Health, told Medical News Today: ”[This study] provides Class I level of evidence (the highest level available) that lonely adults, especially those without major age or genetic risk factors, may have an elevated risk and early neurocognitive vulnerability for developing dementia. This magnifies the population health implications of observed trends in the growing prevalence of loneliness.”
The APOE e4 allele, known as apolipoprotein E, is a fat-binding protein involved in the metabolism of fat and glucose regulation. The allele has a major effect on the progression of age-associated diseases, including Alzheimer’s disease (AD), by influencingTrusted Source the brain function pathways.
Loneliness and dementia: Is there a link?
Even before the COVID-19 pandemic, loneliness was prevalent in the United States. A 2018 survey reports that more than 1 in 5 individuals in the U.S. frequently experienced feelings of loneliness and social isolation. The COVID-19 pandemic has been accompanied by a further riseTrusted Source in the prevalence of loneliness.
Moreover, feelings of loneliness are especially common in older individuals over the age of 60 years, with estimates ranging from 13% to 43%.
“Older people are at a heightened risk of loneliness due to dwindling networks as friends and family die, they live alone or move to an aged care facility where they may be unable to connect to many residents due to communication challenges as a result of dementia. This may result in social isolation, or they may feel lonely,” Dr. Wendy Moyle, the program director of the Healthcare Practice and Survivorship Program at Griffith University, Brisbane, Australia, explained to MNT.
Loneliness can have adverse effects on health and is associated with an increased risk of cardiovascular diseases and all-cause mortalityTrusted Source.
Although some previous studies have shown that loneliness is associated with an increased risk of cognitive decline and dementia, other studies have reported an absence of such an association.
Moreover, whether loneliness causes dementia or is a symptom of these conditions is not understood.
The present study examined the association between loneliness and dementia. To further enhance the understanding of the impact of loneliness on cognitive function, the researchers used data collected from a large sample of dementia-free individuals who were rigorously monitored for dementia over a long follow-up period of 10 years.
Specifically, the researchers obtained data from the Framingham Study, a population-based longitudinal study initiated in 1948 to understand the multigenerational patterns of cardiovascular and other diseases.
To understand the potential role of loneliness in causing dementia, the researchers also examined the association between loneliness and early indicators that precede the clinical symptoms of dementia. To that end, the researchers examined the association between loneliness and early cognitive and brain imaging markers of dementia in healthy individuals.