There have been a few studies done already that link loneliness and Alzheimer’s disease in older adults, and recently another study linked the two together by being able to identify a marker of early Alzheimer’s.
The report was published in the JAMA Psychiatry and found that in a 2010 study from the American Association of Retired Persons roughly 32 per cent of adults aged 60-69 and 25 per cent of adults aged 70 and older in the United States felt lonely.
In addition to increased risks for depression, heart disease, and stroke, loneliness has been found to put older adults at greater risk of cognitive decline and Alzheimer’s disease.
The study looked at whether loneliness could be associated with the level of amyloid protein in a person’s brain. Such proteins have been known to form clumps — called plaques — that are considered precursors to Alzheimer’s disease.
Seventy-nine adults with an average age of 76 years took part in the study. They all had ‘normal cognitive function’.
The team used the Loneliness Scale from the University of California, Los Angeles (UCLA) to rate the level of loneliness each participant felt. Questions in the study included ‘How often do you feel left out?’, ‘How often do you feel isolated from others?’ and ‘How often do you lack companionship?’, with the answers ranked on a scale of 1-4 (1 being ‘never’ and 4 being ‘often’).
The results revealed that the average loneliness score was 5.3 out of 12.
Then the research team used brain imaging to measure the amyloid protein levels in the frontal, lateral temporal and lateral, and medial parietal regions of each participant’s brain.
What they found was that those with low coritcal amyloid levels, compared to those with high levels, were 7.5 times more likely to report feeling lonely and that association was stronger for participants who carried the gene associated with an increased risk of Alzheimer’s disease.
“We report a novel association of loneliness with cortical amyloid burden in cognitively normal older adults, suggesting that loneliness is a neuropsychiatric symptom relevant to preclinical AD [Alzheimer’s disease]. This work will inform new research into the neural underpinnings and disease mechanisms involved in loneliness and may enhance early detection and intervention research in AD,” the study’s co-author Nancy Donovan says.
In Australia, Alzheimer’s disease is the most common form of dementia, affecting up to 70 per cent of people with dementia.