De gevolgen van Alzheimer afhankelijk van sociale contacten.*
Uit een Amerikaanse studie blijkt dat mensen met de kenmerken van Alzheimer in hun hersenen de verstandelijke gevolgen hiervan sterk afhankelijk te zijn van de hoeveelheid sociale contacten die de patiënt onderhoudt. Hoe meer en hoe vaker deze contacten doen de gevolgen zeer sterk reduceren.
Staying
In Touch With Close Friends Reduces Damaging Effects Of Alzheimer's Disease
Having
close friends and staying in contact with family members offers a protective
effect against the damaging effects of Alzheimer's disease according to research
by physicians at Rush University Medical Center in Chicago. The study, which is
currently posted online in The Lancet Neurology, will be published in the
May print edition of the journal.
While other studies have shown people with more extensive social networks were
at reduced risk of cognitive impairment, the study by Dr. David A. Bennett, and
his colleagues from the Rush Alzheimer's Disease Center, is the first to examine
the relations between social networks and Alzheimer's disease pathology.
Researchers studied elderly people without known dementia who are participating
in the Rush Memory and Aging Project, an epidemiological and clinicopathological
study of aging and Alzheimer's disease that involves over 1,100 volunteers
across northeastern Illinois. Brain autopsy was done at the time of death and
post mortem data was available for analysis from the first 89 people.
"Many elderly people who have the tangles and plaques associated with
Alzheimer's disease don't clinically experience cognitive impairment or
dementia," said Bennett. "Our findings suggest that social networks
are related to something that offers a 'protective reserve' capacity that spares
them the clinical manifestations of Alzheimer's disease."
Participants in the study underwent clinical evaluations and 21 cognitive
performance tests each year. To determine social network, participants were
asked about the number of children they have and see monthly. They were asked
about the number of relatives, excluding spouse and children, and friends to
whom they feel close and with whom they felt at ease and could talk to about
private matters and could call upon for help. They were asked to specify how
many of these people they see monthly. Their social network was the number of
these individuals seen at least once per month.
The relationship between the amount of Alzheimer's disease pathology and
cognitive performance changed with the size of the social network. As the size
of the social network increased, the same amount of pathology had less effect on
cognitive test scores. In other words, for persons without much pathology,
social network size had little effect on cognition. However, as the amount of
pathology increased, the apparent protective effect on cognition also increased.
Thus, social network size appears to have offered a protective reserve capacity
despite the fact that their brains had the tangles and plaques indicative of
Alzheimer's disease.
The effect was evident across different kinds of cognitive abilities, but was
most evident for semantic memory, which is the repository of knowledge about the
world and is fundamentally involved in unique human cognitive processes such as
language. The results were unchanged after controlling for cognitive, physical,
and social activities, depressive symptoms, or number of chronic diseases.
"Identifying factors associated with the ability to tolerate the pathology
of Alzheimer's disease has important implications for disease prevention,"
said Bennett. "Previous studies suggest one factor is education. Now we
know that healthy and frequent interactions with friends and family have a
positive impact as well."
The researchers are extremely grateful for the remarkable dedication and
altruism of the volunteers participating in the Rush Memory and Aging Project.
The research was supported by grants from the National Institutes on Aging,
which leads the Federal effort to support and conduct basic, clinical, and
social and behavioral studies on aging and on Alzheimer's disease.
(mei 2006)