Summary: A large meta-analysis of over 600,000 people shows that experiencing loneliness significantly raises the risk of developing dementia by 31%. Researchers found that loneliness is a key factor in cognitive decline, contributing to conditions like Alzheimer’s disease, regardless of age or sex.
The study emphasizes the need to understand how loneliness impacts cognitive health and highlights the importance of interventions to reduce loneliness among aging adults. These findings provide crucial insights into managing dementia risk and improving the well-being of older adults.
Key Facts:
- Loneliness raises dementia risk by 31%, as shown in a study of 600,000 people.
- The effect of loneliness on cognitive decline is independent of age or sex.
- Reducing loneliness could play a key role in preventing dementia and cognitive decline.
Source: FSU
New research led by Florida State University College of Medicine faculty quantified the association between loneliness and dementia by analyzing data from more than 600,000 people around the world — the largest study of its kind.
The meta-analysis of 21 longitudinal studies showed that experiencing feelings of loneliness increased the risk of developing dementia by 31%.
The research was published in Nature Mental Health.
“These results are not surprising, given the mounting evidence that link loneliness to poor health,” said Assistant Professor Martina Luchetti, who led the study.
“Dementia is spectrum, with neuropathological changes that start decades before clinical onset. It is important to continue studying the link of loneliness with different cognitive outcomes or symptoms across this spectrum.
“Loneliness – the dissatisfaction with social relationships – may impact how you are functioning cognitively, and in daily life.”
The analysis revealed that loneliness is a major risk factor for cognitive impairment, independent of age or sex. It also linked loneliness to specific causes of dementia, such as Alzheimer’s disease, and cognitive impairments that can occur before a diagnosis.
The team’s work was spurred by the World Health Organization and U.S. Surgeon General, who declared loneliness a public health crisis in the wake of the COVID-19 pandemic and its associated social restrictions.
“There has been a lot of interest in the consequences of loneliness for health,” Luchetti said. “It is important to understand why and under what circumstances it increases risk for late life dementia.”
Although data for the study included subjects from around the world, most of it was collected from people in wealthier Western Hemisphere cultures. Future research should incorporate more data from other countries, Luchetti said.
“We know there are rising cases of dementia in low-income countries,” she said.
“Future studies need to gather more data from those countries to evaluate what are the effects of loneliness in different national and cultural contexts.”
The meta-analysis results provide information that can guide future prevention and intervention efforts.
“Now that there is solid evidence of an association, it is critical to identify the sources of loneliness to both prevent or manage loneliness and support the well-being and cognitive health of aging adults,” Luchetti said.
The research was supported by a grant from the National Institute on Aging, part of the National Institutes of Health.
Luchetti is an assistant professor in the Department of Behavioral Sciences and Social Medicine. Her co-authors at FSU were Damaris Aschwanden, a post-doctoral researcher; Amanda Sesker, a post-doctoral scholar; Professor Antonio Terracciano of the Department of Geriatrics and Professor Angelina Sutin of the Department of Behavioral Science and Social Medicine, all from the FSU College of Medicine.
Researchers from Wenzhou Medical University, University of Limerick and University of Montpelier were also co-authors.
About this dementia and social isolation research news
Author: Bill Wellock
Source: FSU
Contact: Bill Wellock – FSU
Image: The image is credited to Neuroscience News
Original Research: Closed access.
“A meta-analysis of loneliness and risk of dementia using longitudinal data from >600,000 individuals” by Martina Luchetti et al. Nature Mental Health
Abstract
A meta-analysis of loneliness and risk of dementia using longitudinal data from >600,000 individuals
Loneliness is one critical risk factor for cognitive health. Here we combined data from ongoing aging studies and the published literature and provide the largest meta-analysis on the association between loneliness and dementia (k = 21 samples, N = 608,561) and cognitive impairment (k = 16, N = 103,387).
Loneliness increased the risk for all-cause dementia (hazard ratio (HR) 1.306, 95% confidence interval (CI) 1.197–1.426), Alzheimer’s disease (HR 1.393, 95% CI 1.290–1.504; k = 5), vascular dementia (HR 1.735, 95% CI 1.483–2.029; k = 3) and cognitive impairment (HR 1.150, 95% CI 1.113–1.189).
The associations persisted when models controlled for depression, social isolation and/or other modifiable risk factors for dementia. The large heterogeneity across studies was partly due to differences in loneliness measures and ascertainment of cognitive status.
The results underscore the importance to further examine the type or sources of loneliness and cognitive symptoms to develop effective interventions that reduce the risk of dementia.
