Loneliness associated with increased risk of Alzheimer's disease

Feb 05, 2007

Lonely individuals may be twice as likely to develop the type of dementia linked to Alzheimer's disease in late life as those who are not lonely, according to a study by researchers at the Rush Alzheimer's Disease Center. The study is published in the February issue of Archives of General Psychiatry.

Previous studies have shown that social isolation, or having few interactions with others, is associated with an increased risk of dementia and cognitive decline. However, little was know about the emotional isolation, which refers to feeling alone rather than being alone.

Robert S. Wilson, PhD, and his colleagues, analyzed the association between loneliness and Alzheimer's disease in 823 older adults over a four year period. Participants underwent evaluations that included questionnaires to assess loneliness, classifications of dementia and Alzheimer's disease, and testing of their thinking, learning and memory abilities. Loneliness was measured on a scale of one to five, with higher scores indicating more loneliness.

The data was collected between November 2000 and May 2006.

At the first examination, participants' average loneliness score was 2.3. During the study period, 76 individuals developed dementia that met criteria for Alzheimer's disease. Risk for developing Alzheimer's disease increased approximately 51 percent for each point on the loneliness score, so that a person with a high loneliness score (3.2) had about 2.1 times greater risk of developing Alzheimer's disease than a person with a low score (1.4). The findings did not change significantly when the researchers factored in markers of social isolations, such as a small network and infrequent social activities.

According to Wilson, loneliness is a risk factor for Alzheimer's disease, not an early sign of the disease. Autopsies were performed on 90 individuals who died during the study. Loneliness during life was not related to any of the hallmark brain changes associated with Alzheimer's disease, including nerve plaques and tangles, or tissue damaged by lack of blood flow.

"Humans are very social creatures. We need healthy interactions with others to maintain our health," said Wilson. "The results of our study suggest that people who are persistently lonely may be more vulnerable to the deleterious effects of age-related neuropathology."

The mechanism that does link dementia and loneliness is unclear. Wilson encourages more study to look at how negative emotions cause changes in the brain.

"If loneliness is causing changes in the brain, it is quite possible that medications or changes in behavior could lessen the effects of these negative emotions and reduce the risk of Alzheimer's disease," said Wilson.

Source: Rush University Medical Center

Explore further: Paralyzed man recovers some function following transplantation of OECs and nerve bridge

add to favorites email to friend print save as pdf

Related Stories

Plastic nanoparticles also harm freshwater organisms

14 minutes ago

Organisms can be negatively affected by plastic nanoparticles, not just in the seas and oceans but in freshwater bodies too. These particles slow the growth of algae, cause deformities in water fleas and impede communication ...

Atomic trigger shatters mystery of how glass deforms

16 minutes ago

Throw a rock through a window made of silica glass, and the brittle, insulating oxide pane shatters. But whack a golf ball with a club made of metallic glass—a resilient conductor that looks like metal—and the glass not ...

US company sells out of Ebola toys

8 hours ago

They might look tasteless, but satisfied customers dub them cute and adorable. Ebola-themed toys have proved such a hit that one US-based company has sold out.

UN biodiversity meet commits to double funding

9 hours ago

A UN conference on preserving the earth's dwindling resources wrapped up Friday with governments making a firm commitment to double biodiversity aid to developing countries by 2015.

Recommended for you

Team untangles the biological effects of blue light

9 hours ago

Blue light can both set the mood and set in motion important biological responses. Researchers at the University of Pennsylvania's School of Medicine and School of Arts and Sciences have teased apart the ...

Mouse model provides new insight in to preeclampsia

10 hours ago

Worldwide, preeclampsia is a leading cause of maternal deaths and preterm births. This serious pregnancy complication results in extremely high blood pressure and organ damage. The onset of preeclampsia is associated with ...

User comments : 0