Alzheimer’s disease is a progressive disorder in which the nerve cells (neurons) in a person’s brain and the connections among them degenerate slowly, causing severe memory loss, intellectual deficiencies, and deterioration in motor skills and communication. One of the main causes of Alzheimer’s is the accumulation of a protein called amyloid β (Aβ) in clusters around neurons in the brain, which hampers their activity and triggers their degeneration.
Studies in animal models have found that increasing the aggregation of Aβ in the hippocampus–the brain’s main learning and memory center–causes a decline in the signal transmission potential of the neurons therein. This degeneration affects a specific trait of the neurons, called “synaptic plasticity,” which is the ability of synapses (the site of signal exchange between neurons) to adapt to an increase or decrease in signaling activity over time. Synaptic plasticity is crucial to the development of learning and cognitive functions in the hippocampus. Thus, Aβ and its role in causing cognitive memory and deficits have been the focus of most research aimed at finding treatments for Alzheimer’s.
Older adults with a weaker hand grip were more likely to be cognitively impaired than those with a stronger grip, according to an NIA-funded study in the Journal of Alzheimer’s Disease. The findings suggest that hand grip strength may be a potential low-cost, easy way to help detect cognitive impairment and, in combination with other measures, to identify people who may benefit from early interventions.
A team led by researchers from North Dakota State University looked at data over an eight-year period from almost 14,000 people, age 50 or older, in the NIA-supported Health and Retirement Study. A handheld instrument called a dynamometer was used to assess hand grip strength, and a modified screening tool from the Mini-Mental State Examination was used to measure cognitive function every two years. Of the 13,828 participants who were assessed, 1,309 had some degree of cognitive impairment. Continue reading →
I have written repeatedly about the benefits of exercise on both the body and brain. It turns out that there seems to be a link between loss of muscle mass, sarcopenia, and cognitive decline.
Sarcopenia, the loss of muscle mass, tends to happen naturally with age. So, in older people with sarcopenia, excess body fat may not be readily visible. But hidden fat, paired with muscle mass loss later in life, could predict Alzheimer’s risk, researchers warn.
A recent study — the results of which have been published in the journal Clinical Interventions in Aging — has found that sarcopenia and obesity (independently, but especially when occurring together) can heighten the risk of cognitive function impairments later in life.
The research was conducted by scientists at the Comprehensive Center for Brain Health at the Charles E. Schmidt College of Medicine of Florida Atlantic University in Boca Raton.
“Sarcopenia,” explains senior study author Dr. James Galvin, “has been linked to global cognitive impairment and dysfunction in specific cognitive skills including memory, speed, and executive functions.” Continue reading →
Significant reductions in the risk of mild cognitive impairment (MCI)*, and the combination of MCI and dementia**, have been shown for the first time through aggressive lowering of systolic blood pressure in new research results from the federally-funded SPRINT MIND Study reported at the Alzheimer’s Association International Conference (AAIC) in Chicago.
“This is the first randomized clinical trial to demonstrate a reduction in new cases of MCI alone and the combined risk of MCI plus all-cause dementia,” said Jeff D. Williamson, MD, MHS, Professor of Internal Medicine and Epidemiology and Chief, Section on Gerontology and Geriatric Medicine at Wake Forest School of Medicine. Williamson reported these results at AAIC 2018.
The results of this large-scale, long-term clinical trial provide the strongest evidence to date about reducing risk of MCI and dementia through the treatment of high blood pressure, which is one of the leading causes of cardiovascular disease worldwide.
“This study shows more conclusively than ever before that there are things you can do — especially regarding cardiovascular disease risk factors — to reduce your risk of MCI and dementia,” said Maria C. Carrillo, PhD, Alzheimer’s Association Chief Science Officer. “To reduce new cases of MCI and dementia globally we must do everything we can — as professionals and individuals — to reduce blood pressure to the levels indicated in this study, which we know is beneficial to cardiovascular risk.”