Long-term loneliness may take a tragic toll
For some, loneliness may be a temporary feeling of missing friends, family and intimate relationships. But one University of Colorado researcher believes that long-term loneliness may portend more serious consequences, including cognitive decline and increased risk of Alzheimer’s disease.
“The health outcomes of loneliness are incredibly under-researched at this point, but social factors like loneliness are associated with a 50% increased risk of dementia,” said Dr. Rebecca Mullen, assistant professor in the University of Colorado Department of Family Medicine, who has received a three-year grant from the Alzheimer’s Association to explore links between extended loneliness and heightened potential for dementia.
Greater loneliness has been linked to worsened performance on various measures including global cognition, immediate recall and delayed recall, Dr. Mullen notes. One of her hypotheses that she looks to explore in her research is that loneliness may be a very early symptom of Alzheimer’s disease even before cognition starts declining.
Benefits of proactive treatment
“Previous work has illustrated that those with transient loneliness do not have increased risk for Alzheimer’s disease, while those with persistent loneliness do – apart from depression or genetic risk,” said Dr. Mullen. “This implies that recovery from loneliness may be protective against developing dementia. Therefore, we must find effective interventions to decrease loneliness in older adults as one factor that may help delay the onset of Alzheimer’s.”
Dr. Mullen’s research will explore whether various demographic groups may be affected differently by loneliness, looking at variations by gender, age, racial and ethnic background, marital status, urban vs. rural residence and more.
“Our current patient cohort is 90% White, so we will utilize a variety of community-based engagement efforts to further diversify our population,” she said.
In addition, Dr. Mullen stated that she will factor in other personal/demographic measures such as social support, depression, anxiety and living situation of the study participants.
Chicken and egg
Dr. Mullen noted that there may be an element of “chicken and egg” in the research.
“While loneliness is known to increase the risk of dementia, a number of studies suggest that those with cognitive impairment have higher levels of loneliness than those without cognitive impairment, potentially due to the social disengagement that may occur with increased deficits in comprehension, memory and communication,” she said.
Dr. Mullen believes that the increased cognitive risk posed by loneliness may be comparable to other well-known dementia risk factors, such as physical inactivity and type 2 diabetes, and that the biomarkers associated with loneliness may accumulate in the brain before cognitive decline starts.
“We will test this by including healthy patients without any signs or symptoms of cognitive decline and follow their changes in loneliness, cognition and biomarkers,” she said.
The three-year study
In this study, Dr. Mullen will examine:
- how Alzheimer’s disease biomarkers (i.e. amyloid-ß deposition, pathologic tau and neurodegeneration) are associated with loneliness in patients with mild cognitive impairment (MCI) and healthy older adults, and
- If loneliness is associated with cognitive outcomes in both MCI and healthy aging.
The researchers will assess loneliness in a cohort of older adults participating in longitudinal studies of MCI due to likely Alzheimer’s disease and healthy aging, and analyze data from biomarkers and cognitive assessments.
“This study will be a critical first step to ultimately performing longitudinal assessments of loneliness, developing a conceptual model of the neuropathogenesis of loneliness, and testing therapeutic loneliness interventions to enhance Alzheimer’s treatment,” she said. “Our work will also highlight the potential of recognizing loneliness as an early neurobehavioral change in MCI, ultimately influencing routine Alzheimer’s care.”
The Alzheimer’s Association is the world’s leading non-profit funder of Alzheimer’s research. Currently, the Association has more than $300 million active in 920 research projects in 45 countries.
To learn more about programs and services provided at no charge by the Alzheimer’s Association, go to
alz.org or call the free 24/7 Helpline at 800-272-3900.
Key facts about Alzheimer’s disease
- 76,000 Coloradans are among 6.5 million Americans living with Alzheimer’s disease
- Alzheimer’s kills more people than breast cancer and prostate cancer combined
- Since 2000, deaths from Alzheimer’s have increased 145%, while deaths from heart disease have declined 7%
- Women make up two-thirds of those diagnosed with Alzheimer’s – and two-thirds of the family caregivers
- In Colorado alone, more than 159,000 family and friends are serving as unpaid caregivers, providing an estimated 184 million hours of support in 2021 valued at more than $3.7 billion.
Alzheimer's Association
The Alzheimer's Association leads the way to end Alzheimer's and all other dementia — by accelerating global research, driving risk reduction and early detection, and maximizing quality care and support. Our vision is a world without Alzheimer's and all other dementia.™ For more information, visit www.alz.org or call the 24/7 Helpline at 800.272.3900.