Feeling lonely may affect how well older adults remember things, but it does not appear to make memory decline happen faster over time. This conclusion comes from a large European study that followed more than 10,000 people over a seven-year period.
At the start of the study, participants who reported higher levels of loneliness scored lower on memory tests. However, over the years, their memory declined at about the same rate as those who did not feel lonely.
Large Study Across Europe
The findings were published in the peer-reviewed journal Aging & Mental Health and are based on data from the Survey of Health, Ageing and Retirement in Europe (SHARE). This long-running study included 10,217 adults between the ages of 65 and 94 from 12 European countries.
Loneliness is increasingly recognized as a major public health concern because of its links to lifespan, physical health, mental health, and overall well-being. These results add to evidence connecting loneliness with brain function in older adults, while also suggesting that isolation may not directly increase the risk of dementia.
Why Screening for Loneliness Matters
The researchers suggest that routine checks for loneliness could become part of cognitive health assessments for older adults. The study team included experts from the Universidad del Rosario in Colombia, the Clínica Universitaria de Navarra and Universitat de Valencia in Spain, and the Karolinska Institute in Sweden. They propose that addressing loneliness could be one of several ways to support healthier aging.
“The finding that loneliness significantly impacted memory, but not the speed of decline in memory over time was a surprising outcome,” says lead author Dr. Luis Carlos Venegas-Sanabria, from the School of Medicine and Health Sciences at the Universidad del Rosario.
“It suggests that loneliness may play a more prominent role in the initial state of memory than in its progressive decline.
“The study underscores the importance of addressing loneliness as a significant factor in the context of cognitive performance in older adults.”
Mixed Evidence on Loneliness and Dementia
Loneliness and social isolation are often considered important risk factors for dementia. However, research results have been inconsistent. Some studies have suggested that loneliness speeds up cognitive decline, while others have not found a clear connection.
This study aimed to better understand how loneliness influences changes in memory over time, focusing on both immediate recall and delayed recall across seven years.
How the Study Was Conducted
The analysis used data collected between 2012 and 2019 from SHARE, a long-term project launched in 2002 that tracks the health and aging of people aged 50 and older across Europe.
Participants came from countries including Germany, Spain, Sweden and Slovenia. The 12 countries were grouped into four regions: Central, South, North and Eastern Europe.
People with a history of dementia including Alzheimer’s disease were excluded. Researchers also excluded individuals whose daily living activities were ‘impaired’ (which was classified as people who have any disability in activities such as walking, eating, or taking a shower).
Memory was measured by testing how well participants could recall information both immediately and after a delay. One task required them to remember as many words as possible from a list of 10 that was read aloud within one minute.
Measuring Loneliness and Other Factors
Loneliness was defined as ‘feeling alone’. Participants answered three questions that were used to classify their loneliness as low, average or high.
The questions were as follows: How much of the time do you feel you lack companionship?, How much of the time do you feel left out?, and How much of the time do you feel isolated from others?
Researchers also considered other factors that might influence memory, including physical activity, social engagement, depression scores, diabetes, and other health conditions.
Key Findings on Memory and Loneliness
The highest levels of loneliness were reported in Southern European countries (12%), followed by the Eastern region (9%), Central (6%) and Northern (9%) regions.
Most participants (92%) reported low or average loneliness at the beginning of the study. Those in the high loneliness group (8%) tended to be older, more often female, and reported poorer overall health. They also had higher rates of depression, high blood pressure, and diabetes.
Participants with high loneliness had lower scores on both immediate and delayed memory tests at the start of the study compared to those with lower levels of loneliness.
Memory Decline Over Time
Despite starting at a disadvantage, individuals with higher loneliness did not experience faster memory decline. Their rate of decline was similar to those in the low and average loneliness groups. A sharper drop in memory performance was seen across all groups between year three and year seven.
Important Limitations
The researchers note that loneliness was treated as a fixed trait in this study. In reality, feelings of loneliness can change over time ‘in response to shifts in personal or environmental characteristics across the lifespan’.