Loneliness a Factor in Alzheimer's Disease

A study conducted by Rush University has found that a person's perception of loneliness is a factor for Alzheimer's disease. Researchers studied test subjects who perceived themselves to be socially isolated or disconnected from others. The results showed that lonely people are twice as likely to be diagnosed with Alzheimer's disease as those who aren't.

The research was performed by study leader Professor Robert Wilson, a neuropsychology professor at Rush University Medical Center and Dr. David Bennett, co-author of the study and director of the Rush University Medical Center Alzheimer's Disease Center in Chicago. According to Bennett, it doesn't matter what size social circle a person has; a person can have a small network and not feel lonely, or a large network and feel completely isolated. While previous studies linked those with a small network of friends and family to have a greater risk of Alzheimer's disease, Wilson's and Bennett's work looked at the person's perception, no matter what their network size.

A group of 823 were tested in and around Chicago with the average age of 81. The test subjects showed no signs of dementia at the start and participants' agreed to donate their brains to the Rush Memory and Aging Project for further study. Repeated annually, researchers qualified the subjects' loneliness scale based on a 5-item questionnaire. Participants agreed or disagreed with statements on whether they didn't have enough friends, felt abandoned or experienced emptiness. Scores of 5 was the highest level of loneliness; the average score at the start was 2.3.

Within four years, 76 people in the test group developed Alzheimer's disease. The risk was more than double for the lonely, landing them in the bottom 90th percentile with scores of 3.2, in comparison to those in the top 10 percent who weren't lonely, averaging a score of 1.4. The link between the feelings of loneliness and Alzheimer's disease is evident, despite adjustments factored in, i.e. a small social circle and infrequent socializing. Head of research at the Alzheimer's Society, Dr. Susan Sorensen, agreed that the findings demonstrate a clear link between less social activity and a higher risk of dementia symptoms.

Autopsies were carried out on 90 patients who died during the study in order to look for the physical signs typical of Alzheimer's sufferers. Signs include deposits of protein outside and around the nerve cells of the brain. More research is needed to determine why the physical brain changes typical of Alzheimer's weren't present. Wilson suggested it could be that loneliness may affect systems in the brain dealing with cognition and memory. Lonely people may be more susceptible to the effects of age-related decline in neural pathways. Bennett notes that previous studies have found a link between social isolation, mental decline and a lower risk of dementia.

In single people, social isolation is often brought on by those who participate in few activities with others or have few people in their close knit circle. The average number of people in a social circle is seven; those with 2-4 are at a higher risk than those with 12 people. Other studies show that the depressed and those who feel overwhelmed with stress are at a greater risk for Alzheimer's disease, proving negative emotions are bad for the brain.

Wilson stated the two important take-aways to the study was that loneliness really is a risk factor and to try to understand it, researchers need to look outside the typical neuropathology. This study could affect how the elderly are treated medically, leading healthcare professionals to start asking patients if they are feeling lonely, though it may be easier to admit loneliness than depression or other problems.