Findings of a new study have revealed that nearly everyone will have more memory lapses when they grow old, albeit men tend to be more vulnerable to failing memory compared with women.
For the new study, which was published in JAMA Neurology on March 16, Clifford Jack from the Department of Radiology of the Mayo Clinic and Foundation in Minnesota and colleagues involved more than 1,200 cognitively normal individuals whose age range between 30 and 95 years old.
The researchers found that memory starts to decline for both sexes starting from 30 years old, but the memory of men was worse compared with women, particularly when they reach over 40 years old. The hippocampus, the part of the brain involved in memory, was smaller in men than in women particularly after reaching over 60 years old.
Jack and colleagues said that their study challenges current views on the aging brain. When older adults begin having memory lapses, experts tend to speculate that this is a sign of early Alzheimer's disease associated with the accumulation of the protein known as beta-amyloid in the brain.
The researchers, however, said that the findings show that memory actually declines as people age, and this occurs well before there are amyloid deposits in the brain.
Jack said that the amyloid may likely arise late in life, accelerating pre-existing decline in memory. The researchers found that memory and brain volume gradually decline in people 30 to mid-60 years old, but during this time few people have any amyloid buildup.
"Our findings are consistent with a model of late-onset Alzheimer disease in which β-amyloidosis arises in later life on a background of preexisting structural and cognitive decline that is associated with aging and not with β-amyloid deposits," the researchers wrote.
Men have been found to have consistently worse memories than women. They also tend to have smaller hippocampus at all ages. The researchers suspected that the higher rate of cardiovascular factors in men, which have been associated with the development of memory problems, is one of the reasons why men tend to have poorer recall than women. It is also possible that hormones, estrogen in women, in particular, have protective effects.
"Hypertension, diabetes, smoking: historically, men have had much higher risk factors than women," Jack said. "The same things that harm your vessels harm your brain."
Photo: David Goehring | Flickr