Amnestic mild cognitive impairment often leads to Alzheimer's disease, but what predicts aMCI? A study involving 94 older adults has revealed that lower performance on tests measuring learning, in conjunction with either slower visuomotor processing speed or depressive symptoms, predicted the development of aMCI a year later with an accuracy of 80-100%. It is worth emphasizing that poor learning alone was not predictive in that time-frame, although one learning measure was predictive of aMCI two years later. Interestingly, neither gender nor possession of the ‘Alzheimer’s gene’ —long believed to be risk factors for mild cognitive impairment — had any substantial influence on later impairment.
Memory problems not the only predictor of later mild cognitive impairment
Reference
HAN, D., SUZUKI, H., JAK, A. J., CHANG, Y.-L., SALMON, D. P., & BONDI, M. W. (2010). Hierarchical Cognitive and Psychosocial Predictors of Amnestic Mild Cognitive Impairment. Retrieved from http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=7812581&fulltextType=BT&fileId=S1355617710000512
Related News
Reduced face memorization ability in those with MCI
A small Japanese study has found evidence that those with amnestic mild cognitive impairment (aMCI) show a specific decline in their ability to recognize faces, and this is accompanied by changes in the way they scan faces.
The study involved 18 patients with aMCI and 18 age-matched healthy controls. Participants were tested on their ability to perceive and remember images of faces and houses.
Intensive hypertension treatment reduces risk of cognitive impairment
A clinical trial involving 9361 older adults (50+) with hypertension but without diabetes or history of stroke has found that intensive control of blood pressure significantly reduced the risk of developing mild cognitive impairment.
While there was also a 15% reduction in dementia, this result did not reach statistical significance. This may have been due to the small number of new cases of dementia in the study groups.
Education & IQ linked to later cognitive decline & dementia
Americans with a college education live longer without dementia and Alzheimer's
Data from the large, long-running U.S. Health and Retirement Study found that healthy cognition characterized most of the people with at least a college education into their late 80s, while those who didn’t complete high school had good cognition up until their 70s.
Improving fitness may counteract brain atrophy in older adults, including those with MCI
A study involving 30 previously physically inactive older adults (aged 61-88) found that a three-month exercise program reversed some brain atrophy.
Participants included 14 with MCI. The exercise program included moderate intensity walking on a treadmill four times a week over a twelve-week period. On average, cardiorespiratory fitness improved by about 8% as a result of the training in both the healthy and MCI participants. Fitness was assessed using peak oxygen capacity rates.
Plaques tell which MCI patients will progress to Alzheimer’s
Submitted by Fiona McPherson
on
A three-year study involving 152 adults aged 50 and older, of whom 52 had been recently diagnosed with mild cognitive impairment and 31 were diagnosed with Alzheimer's disease, has found that those with mild or no cognitive impairment who initially had amyloid-beta plaques showed greater cognitive decline than those whose brain scans were negative for plaques. Moreover, 35% of plaque-positive participants who started with MCI progressed to Alzheimer's, compared to 10% without plaque, and they were more than twice as likely to be started on cognitive-enhancing medication.
Tau-amyloid ratio predicts MCI
Submitted by Fiona McPherson
on
Initial findings from an analysis of cerebrospinal fluid taken between 1995 and 2005 from 265 middle-aged healthy volunteers, of whom 75% had a close family member with Alzheimer’s disease, has found that the ratios of phosphorylated tau and amyloid-beta could predict mild cognitive impairment more than five years before symptom onset — the more tau and less amyloid-beta, the more likely MCI will develop. The rate of change in the ratio over time was also predictive — the more rapidly the ratio of tau to amyloid-beta went up, the more likely the eventual development of MCI.
Brainwaves indicate the presence and severity of Alzheimer's
Submitted by Fiona McPherson
on
Comparison of the EEGs of 27 healthy older adults, 27 individuals with mild Alzheimer's and 22 individuals with moderate cases of Alzheimer’s, has found statistically significant differences across the three groups, using an algorithm that dissects brain waves of varying frequencies.
Site of plaque buildup matters
Submitted by Fiona McPherson
on
Analysis of brain scans and cognitive scores of 64 older adults from the NIA's Baltimore Longitudinal Study of Aging (average age 76) has found that, between the most cognitively stable and the most declining (over a 12-year period), there was no significant difference in the total amount of amyloid in the brain, but there was a significant difference in the location of amyloid accumulation. The stable group showed relatively early accumulation in the frontal lobes, while the declining group showed it in the temporal lobes.
Physical activity saves hippocampus in people at risk of Alzheimer's
Submitted by Fiona McPherson
on
A study involving 97 healthy older adults (65-89) has found that those with the “Alzheimer’s gene” (APOe4) who didn’t engage in much physical activity showed a decrease in hippocampal volume (3%) over 18 months. Those with the gene who did exercise showed no change in the size of their hippocampus, nor did those without the gene, regardless of exercise. Physical activity was classified as low if the participant reported two or fewer days per week of low intensity activity, such as no activity, slow walking or light chores.
Limited benefit of physical activity for preventing cognitive decline
A large, two-year study challenges the evidence that regular exercise helps prevent age-related cognitive decline.
The study involved 1,635 older adults (70-89) who were enrolled in the Lifestyle Interventions and Independence for Elders (LIFE) study. They were sedentary adults who were at risk for mobility disability but able to walk about a quarter mile. Participants had no significant cognitive impairment (as measured by the MMSE) at the beginning of the study. Around 90% (1476) made it to the end of the study, and were included in the analysis.