Amnestic mild cognitive impairment doubles risk of death
Researchers at Albert Einstein College of Medicine of Yeshiva University and Montefiore Medical Center have found that people with a form of mild cognitive impairment (MCI), a risk factor for developing Alzheimer's disease, have twice the risk of dying compared with cognitively normal people. Those with dementia have three times the risk. The findings are being presented at the Alzheimer's Association International Conference in Vancouver this week.
Amnestic MCI is a condition in which people have memory problems more severe than normal for their age and education, but not serious enough to affect daily life. (Another form of MCI, nonamnestic MCI, is characterized by impaired thinking skills other than memory, such as trouble planning and organizing or poor judgment.) According to the Alzheimer's Association, long-term studies suggest that 10 to 20 percent of people aged 65 and older may have MCI.
Einstein researchers studied 733 individuals enrolled in the Einstein Aging Study. The participants were at least 70-years-old and lived in The Bronx. At the start of the study, each had a cognitive evaluation for baseline and at least one annual follow-up visit. They were also tested for the APOE-4 gene variant, which is linked to increased risk for Alzheimer's. Participants were followed for an average of five years (up to a high of 16 years).
Study investigators found that participants with amnestic MCI had more than two times (2.17) greater risk of death. Nonamnestic MCI did not appear to increase mortality risk. The risk of death among participants with dementia was more than three times greater (3.26) than that of those who were cognitively normal. Researchers also found that having the APOE-4 gene variant, a greater number of co-morbidities, and severe depression were also related to higher risk of mortality.
"While there is no treatment for MCI, dementia or Alzheimer's, these findings support the benefits of early detection and monitoring of cognitive impairment in order to prolong life," said Richard Lipton, M.D., the senior author of the study and director of the Einstein Aging Study. Dr. Lipton is also the Edwin S. Lowe Chair in Neurology at Einstein and professor and vice chair of the Saul R. Korey Department of Neurology at Einstein and Montefiore Medical Center, the University Hospital for Einstein.
The Einstein Aging Study examines both normal brain aging and the special challenges of Alzheimer's disease and other dementias. Since its initial funding 30 years ago by the National Institute on Aging (AG003949), part of the National Institutes of Health, its investigators have contributed to the understanding of brain aging by tracking over 2,000 Bronx County residents in order to facilitate earlier diagnosis, prevention and treatment of Alzheimer's disease.