New guidelines and drugs for slowing Alzheimer's
March 1, 2023 | View PDF
Preventing heart attacks in new ways
After years of research, scientists have now developed a wearable cardiac ultrasound imager that can non-invasively capture real-time images of the human heart for an extended period of time. The patch, which is about the size of a postage stamp, is comparable to a commercial ultrasound device. Further, the imager can be worn during exercise and provide valuable cardiac information when the heart is under stress.
“While existing wearable patches in development can capture things like heart rate and blood pressure, they are not designed to provide in-depth information about heart function,” said Randy King, a program director in the Division of Applied Science & Technology at National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, Maryland. “This innovative ultrasound device gives critical insight about the heart in real time, providing clinicians with detailed, actionable cardiac information. Combined with its thin design and stretchable properties, this patch could pave the way for continuous, non-invasive cardiac monitoring.”
Heart disease is the leading cause of death worldwide. In the U.S., it is estimated that someone dies every 34 seconds from cardiovascular disease. Diagnosis for heart disease remains a challenge, as most methods only provide a snapshot of cardiac function, which may not be representative of overall heart health. The new patch allows physicians to evaluate heart performance throughout exercise, providing valuable information about the heart when it is under high stress. The researchers write that this could allow for real-time visualization of heart anomalies as they manifest, which might be missed under normal stress test conditions.
The researchers wanted to determine if their patch could be used to calculate key cardiac functions, such as stroke volume, cardiac output, and ejection fraction (which are all related to how much blood is pumped out of the heart and how efficiently the heart is working). Using deep learning, they extracted specific features from ultrasound images taken with their patch and trained a model to reliably extrapolate these cardiac metrics.
“The ability to non-invasively and continuously monitor such cardiac functions over a 24-hour period could revolutionize the field,” said study investigator Ray Wu, who is also with NIBIB.
New Alzheimer’s drug showing promise
The U.S. Food and Drug Administration (FDA) recently granted approval to Lecanemab, the first Alzheimer’s disease treatment to win approval since the largely failed rollout of Aduhelm two years ago. Sold under the brand name Leqembi, the new drug shows promise, but it is not yet widely available.
Increasing age is the greatest known risk factor for Alzheimer’s disease. Alzheimer’s is not a part of normal aging, but as you grow older the likelihood of developing Alzheimer’s disease increases. There is not a single cause of Alzheimer’s disease. It likely develops from multiple factors, such as genetics, lifestyle and environment.
“The clinical data on Leqembi is solid and shows moderately less decline for those participants who received the drug compared to those who did not in the Phase III study,” said Dr. Sarah Kremen, who leads the Alzheimer’s Disease Clinical Trial Program at Cedars-Sinai Medical Center, Los Angeles, California. “But before making this treatment available to patients, we have to take steps to ensure that we’re giving the drug as safely as possible to patients who will face the least risk and receive the greatest benefit. This is a critical process that takes time.”
The data showed that the treatment can pull amyloid (a protein that forms plaques and disrupts brain function) out of the brain in a significant way. Patients receiving Leqembi during clinical trials also showed slowing in decline on tests of memory and functional ability. Leqembi appears to decrease accumulation of tau protein, which forms tangles inside the brain. While these results are exciting, this medication does not reverse cognitive decline, it only slows it down.
Current medications to treat Alzheimer’s disease are different from Leqembi because they are not disease-modifying. This means that they may help memory for some amount of time, but they do not have an effect on the underlying disease process, such as the buildup of amyloid and tau proteins in the brain. The medication is given by IV infusion over one hour, every two weeks. Patients will need to have an MRI before the fifth, seventh and 14th infusions, according to FDA guidelines, to monitor for any adverse side effects.
Combating Alzheimer’s disease in a new way
An international task force, led by the University of Geneva (UNIGE) and the Geneva University Hospitals (HUG), is setting out guidelines for innovative services to prevent Alzheimer’s disease. The guidelines, which have been published in the Lancet Regional Health Europe, hopefully will soon be an integral part of second generation memory clinics. Improved lifestyles (physical activity, attention to nutrition, cardiovascular prevention) have reduced the risk of developing Alzheimer’s disease or related forms. However, the prevalence of dementia continues to rise with the aging population. The international task force is composed of scientists from 28 institutions.
“Some of the recommended interventions are ready to be applied or are already applied. Others are still under development,” said Giovanni Frisoni, a professor of Clinical Neuroscience at the UNIGE Faculty of Medicine and Director of the HUG Memory Centre. The task force has identified four key areas of emphasis: risk assessment, risk communication, risk reduction and cognitive enhancement.
The risk factors for Alzheimer’s disease or related disorders and their weight have been grouped together in an evaluation grid. These include factors associated with genes, such as APOE4, or those linked to lifestyle or conditions, such as hypertension, diabetes, alcohol consumption, social isolation, obesity, hearing loss, depression or head trauma.
A series of recommendations are based on the patient’s personality and background for choosing the best tools for presenting the situation to the patient in a comprehensible manner. Drug and non-drug interventions are proposed for risk reduction. Different types of memory can be reinforced or stimulated through paper-based exercises or computer games. Transcranial electrical or magnetic stimulation will also be an important tool to activate synapses in key brain regions.
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at firstname.lastname@example.org.