The American Academy of Neurology has updated its guidelines on when people with dementia should stop driving. While the guidelines point out that this decision is a complex one that should be made by a doctor using the Clinical Dementia Rating scale, they also supported caregivers’ instincts, which have been found to often be correct. For caregivers and family members, the following warning signs are identified:
Another gene has been identified that appears to increase risk of Alzheimer’s. The gene, MTHFD1L, is located on chromosome six. Comparison of the genomes of 2,269 people with late-onset Alzheimer's disease and 3,107 people without the disease found those with a particular variation in this gene were almost twice as likely to develop Alzheimer's disease as those people without the variation. The gene is involved in influencing the body's levels of homocysteine (high levels are known to be a strong risk factor), and have also been implicated in coronary artery disease.
Previous research has found that unexplained weight loss is an early sign of Alzheimer's. Now a study involving 140 older adults (60+), of whom half had early-stage Alzheimer's disease, has revealed that it is not the overall weight or fat levels that are important, but the loss of lean mass (weight of an individual's bones, muscles and organs without body fat). This directly correlated with reductions in the volume of the whole brain and of white matter only, along with declines in cognitive performance.
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.
A pilot study involving 21 institutionalized individuals with moderate-to-severe Alzheimer’s found that, although drinking two 4-oz glasses of apple juice daily for a month produced no change in the Dementia Rating Scale or in the Activities of Daily Living measure, there was a significant (27%) improvement in behavioral and psychotic symptoms. The largest changes occurred in anxiety, agitation, and delusion.
A pilot study involving 10 patients with moderate Alzheimer's disease, of whom half were randomly assigned to the treatment, has found that two weeks of receiving daily (25 minute) periods of repetitive transcranial magnetic stimulation to the prefrontal lobes produced a significant improvement in the patients’ ability to understand spoken language. Correct answers on a comprehension test rose from 66% to over 77%. Two further weeks of the treatment produced no further improvement, but the improvements were still evident eight weeks after the end of the treatment.
A study involving outpatients with early stage Alzheimer’s found that their performance on some computerized tests of executive function and visual attention, including a simulated driving task, improved significantly after three months of taking cholinesterase inhibitors. Specifically, the drug treatment was associated with an improved ability to accurately maintain lane position during the simulated driving task; to accurately and quickly detect a target in a visual search task; to more quickly complete computerized mazes.
A study involving 54 older adults (66-76) and 58 younger adults (18-35) challenges the idea that age itself causes people to become more risk-averse and to make poorer decisions. Analysis revealed that it is individual differences in processing speed and memory that affect decision quality, not age. The stereotype has arisen no doubt because more older people process slowly and have poorer memory.
A large longitudinal study, comparing physical activity at teenage, age 30, age 50, and late life against cognition of 9,344 women, has revealed that women who are physically active at any point have a lower risk of cognitive impairment in late-life compared to those who are inactive, but teenage physical activity is the most important. When age, education, marital status, diabetes, hypertension, depressive symptoms, smoking, and BMI were accounted for, only teenage physical activity status remained significantly associated with cognitive performance in old age.
A study involving 733 participants from the Framingham Heart Study Offspring Cohort (average age 60) provides more evidence that excess abdominal fat places otherwise healthy, middle-aged people at greater risk for dementia later in life. The study also confirms that a higher BMI (body mass index) is associated with lower brain volumes in both older and middle-aged adults. However the association between visceral fat and total brain volume was independent of BMI. Visceral fat differs from subcutaneous fat in that it is buried deeper, beneath the muscles, around the organs.