Older adults who feel lonely score measurably worse on memory tests than those who don’t, but their memory does not deteriorate any faster. That’s what a recent survey of more than 10,000 Europeans over six years shows and how scientists and doctors should understand social isolation in light of the public health risks.
According to the results of their research, published in the journal Aging & Mental Health, the team of Luis Carlos Venegas-Sanabria, professor at the Universidad del Rosario School of Medicine and Health Sciences, based their work on information provided by the Survey of Health, Aging and Retirement in Europe (SHARE).
Over six years, 10,217 adults aged 65 to 94, from 12 European countries, were assessed on their loneliness levels and performance on immediate and delayed memory tests. The results were consistent: higher loneliness correlated with lower initial memory scores. However, the rate of decline was almost identical to that of participants who did not report loneliness.
“It suggests that loneliness may play a more prominent role in the initial state of memory than in its progressive decline,” Venegas-Sanabria said.
Age remained the most important predictor of memory performance. The declines became more pronounced after age 75 and increased dramatically after age 85. Depression and other medical conditions such as diabetes lowered baseline scores, regardless of loneliness.
On the other hand, physical activity had the opposite effect. Individuals who performed moderate or strenuous physical activities at least once a month showed better recall performance on immediate and delayed tasks. Researchers described this effect as a cognitive buffer; it increased baseline without changing how quickly memory declined over time.
There are practical implications of this discovery. If loneliness only hinders normal cognitive capacity without leading to neurodegenerative disorders, then it would be better to start treatment through socialization at a younger age, when people are under 70 years old, allowing them to maintain a higher baseline level for longer periods.
It has been suggested that previous studies have identified many ways in which loneliness can negatively impact cognitive functioning. These include fewer social interactions, a higher incidence of depression, and a higher incidence of hypertension and other medical conditions that can cause cognitive impairment.
