Over the 12-year study, participants reporting loneliness experienced 20% faster cognitive decline than other participants. This result held true regardless of factors like demographics, socioeconomic status and the presence of other debilitating health conditions. Higher levels of depression also correlated significantly with more rapid cognitive decline.
“Our study suggests that even one or two depressive symptoms – particularly loneliness – is associated with an increased rate of cognitive decline over 12 years,” said Nancy J. Donovan, MD, of the Brigham and Women’s Hospital. “We found that lonely people decline cognitively at a faster rate than people who report more satisfying social networks and connections.”
The researchers also evaluated the possibility that reduced cognitive function might lead to greater loneliness, but didn’t find evidence to support a link in that direction.
“Although loneliness and depression appear closely linked, loneliness may, by itself, have effects on cognitive decline. This is important to know as we develop treatments to enhance cognitive health and quality of life for older adults,” added Donovan.
