Feeling lonely can affect older people’s ability to remember things, but it doesn’t seem to accelerate memory decline over time. This conclusion comes from a large European study that followed more than 10,000 people for seven years.
Participants who reported higher levels of loneliness at the beginning of the study had lower scores on memory tests. But over the years, their memory declined at about the same rate as those who didn’t feel lonely.
Large-scale research across Europe
The findings were published in a peer-reviewed journal Aging and mental health This is based on data from the Survey of Health, Aging and Retirement in Europe (SHARE). The long-term study involved 10,217 adults aged 65 to 94 from 12 European countries.
Loneliness is increasingly recognized as a major public health concern because of its association with longevity, physical health, mental health, and overall well-being. While these results add to the evidence linking loneliness and brain function in older adults, they also suggest that isolation may not directly increase the risk of dementia.
Why screening for loneliness is important
Researchers suggest that regularly checking for loneliness could become part of an older adult’s cognitive health assessment. The research team included experts from the University of Rosario in Colombia, the Clinical Universities of Navarre and Valencia in Spain, and the Karolinska Institute in Sweden. They suggest that addressing loneliness may be one of several ways to support healthier aging.
“The finding that loneliness has a strong effect on memory, but not the rate of memory decline over time, was a surprising result,” said lead author Dr. Luis Carlos Venegas Sanabria, from the Faculty of Medicine and Health Sciences at the University of Rosario.
“That suggests that loneliness may play a more prominent role in the initial state of memory than in its progressive decline.
“This study highlights the importance of addressing loneliness as a key component of cognitive performance in older adults.”
Compounding evidence on loneliness and dementia
Loneliness and social isolation are often considered important risk factors for dementia. However, research results are inconsistent. Some studies suggest that loneliness accelerates cognitive decline, while others find no clear link.
The study aimed to better understand how loneliness affects changes in memory over time, focusing on both immediate and delayed memory over a seven-year period.
How to conduct research
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 over across Europe.
Participants came from countries such as Germany, Spain, Sweden, and Slovenia. The 12 countries were grouped into four regions: Central Europe, Southern Europe, Northern Europe, and Eastern Europe.
People with a history of dementia, including Alzheimer’s disease, were excluded. The researchers also excluded people who were “impaired” in activities of daily living (classified as people who had some impairment in activities such as walking, eating, or showering).
Memory was measured by testing how well participants could recall information both immediately and after a delay. One task required participants to memorize as many words as possible from a list of 10 words read aloud within one minute.
Measuring loneliness and other factors
Loneliness was defined as “feeling alone.” Participants answered three questions that were used to categorize their loneliness as low, average, or high.
The questions are: How much time do you feel lacking in company?, How much time do you feel excluded?, How much time do you feel isolated from others?
The researchers also considered other factors that may affect memory, such as physical activity, social engagement, depression scores, diabetes, and other health conditions.
Key discoveries about memory and loneliness
Loneliness was highest in southern European countries (12%), followed by eastern regions (9%), central regions (6%) and northern regions (9%).
Most participants (92%) reported low or average loneliness at the beginning of the study. Those with higher levels of loneliness (8%) tend to be older, more likely to be female, and report poorer overall health. They also had higher rates of depression, hypertension, and diabetes.
Participants with high levels of loneliness had lower scores on both immediate and delayed memory tests at the beginning of the study compared to participants with low levels of loneliness.
Memory declines over time
Despite starting from a disadvantageous position, those who were more lonely did not experience faster memory decline. Their attrition rates were similar to the low and average loneliness groups. From year 3 to year 7, there was a sharp decline in memory in all groups.
Important limitations
The researchers note that the study treated loneliness as a fixed trait. In fact, feelings of loneliness can change over time “in response to changes in personal or environmental characteristics over the lifespan.”
