David Bunce, PhD, a psychologist at Goldsmith's College, University of London, Miia Kivipelto, PhD, MD, of the Aging Research Center at the Karolinska Institute in Stockholm and the Stockholm Gerontology Research Center, and Åke Wahlin, PhD, a psychologist at the University of Stockholm, conducted the study as part of a long-term multidisciplinary project that follows older people living in Stockholm's Kungsholmen parish.
Scientists already knew of a genetic predisposition for Alzheimer's disease, and that low levels of two B vitamins-- B12 and folate--were also linked to problems. However, few had examined nutrition and genotype together relative to cognition, to reflect what real people carry into old age a mix of inborn traits and environmental factors such as nutrition, including undiagnosed vitamin B deficiencies.
The apolipoprotein E gene, which moves cholesterol in the body, has a version called the є4 allele. Carried by perhaps 15 percent of the population, it is a risk factor for dementia. Current data collected over a six-year period suggests that nearly one out of four carriers with one copy of this allele and nearly half carrying two copies will develop Alzheimer's disease. Non-carriers also can get Alzheimer's.
Carriers of the є4 allele have smaller hippocampi, brain areas associated with memory, so the researchers wanted to measure how an additional physiological shortfall such as low Vitamin B, affected this particular group -- given that reduced B12 and folate have been linked generally with diminished memory and increased risk for Alzheimer's.
'"/>
Contact: Pam Willenz
public.affairs@apa.org
202-336-5700
American Psychological Association
4-Apr-2004