Research co-investigator Dr Rosebud Roberts, associate professor of epidemiology at the Mayo Clinic in Rochester, Minnesota, and member of the American Academy of Neurology, presented the study yesterday, Wednesday, at the Academy's 60th Anniversary Annual Meeting, which is taking place in this week, from 12th to 19th April.
"This is one of the first studies to determine the prevalence of mild cognitive impairment among men and women who have been randomly selected from a community to participate in the study," said Roberts in a prepared brief.
A person is described as having cognitive impairment when they show problems with memory and thinking that is beyond what a specialist might expect for their age and level of education.
Although mild cognitive impairment appears to increase the risk of developing Alzheimer's Disease later, not everyone who has it develops Alzheimer's.
Investigators interviewed, examined and administered cognitive tests to 2,050 people aged between 70 and 89, living in Olmsted County, Minnesota.
The also interviewed people who knew the participants well, for example a wife or husband, about the participants' everyday cognitive functioning.
The participants were classed into three groups: normal cognitive functioning, mild impairment, or dementia.
The results showed that:
- 16.7 per cent of the group had mild cognitive impairment.
- Men were 1.6 times more likely to have mild cognitive impairment than women.
- This statistic was the same regardless of the men's level of education or marital status.
Speculating on why this might be so, Roberts suggested that perhaps:
"There's a delayed progression to dementia in men," or "women may develop dementia at a faster rate than men".
Dr Sam Gandy, chairman of the medical and scientific advisory council for the Alzheimer's Association in the US told WebMD that he thought the study was "scientifically sound", but the results should be seen in perspective. The genetic risk factors involved in dementia are much greater in magnitude, he suggested.
Gandy also said that lifestyle factors are important too, and both men and women can reduce their risk of getting dementia.
The Alzheimer's Association recommends people maintain an active lifestyle rich in mental, social and physical activity and adopt a "brain-healthy" diet that is low in fat and cholesterol and high in dark vegetables and fruit.
Dementia is a general term for when the loss of memory and thinking skills is severe enough to prevent a person from doing normal everyday things such as taking care of themselves, going shopping, paying bills, washing, preparing meals.
The most prevalent forms of dementia are Alzheimer's disease, a progressive and fatal illness that destroys brain cells, and vascular dementia, caused by reduced blood flow in the brain.
According to the Alzheimer's Association, there are 5 million Americans living with Alzheimer's.
Click here for American Academy of Neurology
Source: American Academy of Neurology press release, WebMD, Alzheimer's Association.