According to a 2010 survey by the American Association of Retired Persons, about 32% of adults ages 60-69 and 25% of adults age 70 and older in the United States feel lonely. In addition to the increased risk of depression, heart disease or stroke , loneliness in older people has been linked to an increased risk of cognitive decline.
A Yes, previous research had suggested that loneliness can be associated with Alzheimer’s disease among the elderly. Now, a new study carried out by experts from Brigham and Women’s Hospital and Harvard University School of Medicine (USA) supports this relationship, after identifying a marker of early Alzheimer’s in the brains of older people with greater loneliness. The study has been published in the journal JAMA Psychiatry .
For their study, the researchers wanted to determine whether loneliness was associated with pathological changes in the brain that could be a marker for Alzheimer’s . Specifically, they analyzed whether loneliness could be associated with levels of amyloid proteins in the brain (which form plaques, a hallmark of Alzheimer’s disease). For this, they had the participation of 79 adults, 43 women and 36 men, with an average age of 76 years and with normal cognitive functioning. All of them completed a questionnaire on loneliness with questions such as: How many times do you feel isolated from others? How many times do you feel lonely? The results yielded an average score of 5.3 out of 12.
The volunteers also underwent brain scans to measure levels of amyloid protein in cortical areas of the brain, including the frontal, lateral, lateral temporal and medial parietal regions.
Adults with high levels of amyloid protein were 7.5 times more likely to feel lonely compared to subjects with low levels of this protein. This association was even more palpable in the participants who carried the APOE4 gene, apolipoprotein E, a gene already linked to an increased risk of Alzheimer’s disease.
“We present a new association between loneliness and cortical amyloid load in cognitively normal elderly and present evidence of loneliness as a relevant neuropsychiatric symptom for preclinical Alzheimer’s disease,” explains Nancy J. Donovan, leader of the work.





