More than 40 percent of elderly women ages 85 and over had symptoms of Alzheimer's disease or other serious problems with thinking and memory, according to a new report. The findings are important, since the numbers of these "oldest old," the fastest growing segment of the United States population, are expected to increase by 40 percent in the next decade alone.
“Screening for cognitive disorders in the oldest old is of the utmost importance, especially in high-risk groups,” the authors, from the University of California at San Francisco conclude.
They looked at nearly 1,300 women ages 85 and up, all part of the Women Cognitive Impairment Study of Exceptional Aging, an ongoing study that has followed thousands of women living in Baltimore, Minneapolis, Portland, Ore., and Pennsylvania for many years. Twenty seven percent were over 90. Six hundred thirty four of the women, or 41 percent, had serious memory and thinking problems, while the remaining 665 tested normal on cognitive exams.
Alzheimer's and other forms of dementia accounted for many of the cognitive problems in these elderly women. Most of those with dementia had Alzheimer's or a mix of Alzheimer's and vascular dementia, caused by blood vessel disease affecting the brain. About 12 percent had vascular dementia alone. Mild cognitive impairment, a serious form of memory loss that can lead to Alzheimer's, was also common among this group.
Alzheimer's and other cognitive problems were more common in women over 90, and in those with fewer years of schooling or a history or stroke or depression. Compared with their mentally sharper peers, women with dementia were also more likely to live in a nursing home and to carry the APOE-E4 gene, a gene that increases the risk of Alzheimer's. The findings appeared in Archives of Neurology, a journal from the American Medical Association.
Research indicates that the incidence of Alzheimer's and other types of dementia almost doubles with every 5 years of age after age 65. About 2 to 3 percent of people ages 65 to 75 have dementia, compared to 35 percent in those 85 and older.
The prevalence of mild cognitive impairment was higher in women over 90 (24.5 percent) than in women 85 to 89 (22.7 percent). Most, but not all, had serious memory problems.
The authors note that understanding Alzheimer's and related problems in the elderly is critical for public health planning, as the population continues to age and the oldest old become more common and continue to grow older.
Source: Impairment, Dementia, and Their Subtypes in Oldest Old Women." Archives of Neurology, Vol 68 (Number 5), May 9, 2011, pages 631 to 636.