Rethinking The Causes Of Alzheimer’s

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For many years, the majority of brain researchers have assumed that the accumulation of amyloid plaques in the brain is the principal cause of Alzheimer’s disease. It was thought the decline in cognition was caused by the development of the plaques. Yet despite many expensive attempts at developing anti-amyloid drugs, little or nothing in the way of successful therapies is available. This has led some researchers to explore whether or not the amyloid plaques, although clearly involved with the disease, are not the proximate cause. The amyloid hypothesis has been questioned, given the large number of clinical trials in which drugs targeted and successfully cleared amyloid from the brain but did not halt or reverse cognitive decline.

Recently published work seems to point in this direction. The researchers used brain scans combined with Obj-SCD (“objectively-defined subtle cognitive difficulties”), a refined set of tests for assessing cognition. Their work appears to show that development of amyloid plaques did not emerge before the development of subtle cognitive difficulties.

Here are five links to media articles on the work:
We Just Got More Evidence Our Leading Hypothesis About Alzheimer’s Could Be Wrong
Objective subtle cognitive difficulties predict amyloid accumulation and neurodegeneration
Which Comes First, Cognitive Problems Or Beta-amyloid Plaques?
Amyloid Accumulation Doesn’t Always Precede Cognitive Decline
What causes Alzheimer’s? Not toxic amyloid, new study suggests

Here is a link to the research paper:
Objective subtle cognitive difficulties predict future amyloid accumulation and neurodegeneration

All links have been added to Alzheimer’s > Neurology & Neuroplasticity.

Lifestyle Affects Both Alzheimer’s & FTD

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Alzheimer’s disease (60-80%) and Frontotemporal dementia (FTD) (10-20%) make up the two largest populations of dementia sufferers (Dementia with Lewy bodies comprises another 5%). Two fairly recently published studies have examined the effects of lifestyle changes on both Alzheimer’s and FTD. Both studies considered the participants’ physical and cognitive activities to create a definition of “active lifestyle” for the participants. For both the Alzheimer’s and FTD studies, participants with the greatest activity scores showed the greatest resistance to cognitive decline (for those not already showing mild cognitive impairment) or the greatest reduction in rate of cognitive decline (for those already showing some mild cognitive impairment).

Here are links to three media articles on lifestyle & Alzheimer’s:
People at Risk of Alzheimer’s May Improve Brain Function With Individualized Treatment
Lifestyle changes improved cognition in people at risk for Alzheimers, study shows
Could Regimented, Prescribed & Individualized Lifestyle Changes Improve Cognition in People at Risk for Alzheimer’s Disease?

Here is a link to the research article on lifestyle & Alzheimer’s:
Individualized clinical management of patients at risk for Alzheimer’s dementia

Here are links to three media articles on lifestyle & FTD:
Lifestyle changes may combat a dementia that strikes people in their 40s and 50s
Lifestyle Choices Could Slow Familial Frontotemporal Dementia
Active lifestyle may slow inherited frontotemporal dementia

Here is a link to the research report on lifestyle & FTD:
Active lifestyles moderate clinical outcomes in autosomal dominant frontotemporal degeneration

All links have been added to Health > Physical Exercise and Alzheimers > Mental Exercise.

Exercise & Brain: Four 2019 Articles

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At the end of this past December, the NY Times published an overview/review (Move Your Body, Bolster Your Brain) of four 2019 articles covering research work on physical exercise and brain health. We’ll recap these below, providing additional media links along the way.

A Single Workout Can Alter the Brain (How Exercise Affects Our Memory)

A study of healthy older adults shows that just one 30 minute session of exercise increased activation in the brain circuits associated with memory — including the hippocampus. The latter shrinks with age and is the brain region attacked first in Alzheimer’s disease.

Here are two additional media articles:
Exercise activates memory neural networks in older adults
30 Minutes of Aerobic Exercise Supercharges Semantic Memory

Here is a link to the research publication:
Semantic Memory Activation After Acute Exercise in Healthy Older Adults

How Exercise May Sharpen Memory (How Exercise May Help Keep Our Memory Sharp)

New evidence reaffirms suggestions that exercise-induced irisin, a hormone, may protect against neurodegeneration and boost memory in both humans and mice.

Here are three additional media articles:
How exercise may protect against Alzheimer’s
Exercise-Linked Irisin May Protect Against Neurodegeneration
‘Exercise Hormone’ Could Slow Progression of Alzheimer’s Disease

Here is a link to the research publication:
Exercise-linked FNDC5/irisin rescues synaptic plasticity and memory defects in Alzheimer’s models

Weight Training Changes the Brain (How Weight Training Changes the Brain)

Until recently the majority of research on exercise and brain health has been done with aerobic exercise, which indeed, has show that exercise is good for your brain. Now, new work using lab rats has demonstrated that weight training can overcome cognitive impairment and even jumpstart the creation of new neurons.

Here are three additional media articles:
Weight Training – Good for the Brain Too?
Research shows surprising link between weightlifting and cognition
Strong Rat. Smart Rat. Got That?

Here is a link to the research publication:
Resistance-exercise training ameliorates LPS-induced cognitive impairment concurrent with molecular signaling changes in the rat dentate gyrus

The Right Kind of Exercise to Lower Dementia Risk (The Right Kind of Exercise May Boost Memory and Lower Dementia Risk)

It is never too late to begin exercising. This study shows that even starting in your 60’s, you can reduce your risk of dementia. Short intense sessions may be the most helpful.

Here are three additional media articles:
Improved fitness can mean living longer without dementia
Being Physically Fit Reduces the Risk of Dementia
Robust Workouts Guard Brains & Health at Any Age

Here is a link to the research publication:
Temporal changes in cardiorespiratory fitness and risk of dementia incidence and mortality: a population-based prospective cohort study

All the links above have been added to Health > Physical Exercise

Dementia, Depression And A New Path

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It is not at all uncommon for a person suffering from mild cognitive impairment or mild to moderate dementia to also suffer from depression. There is enough overlap between the signs and symptoms of each disease that teasing apart the diagnoses, or verifying the presence of both, can be difficult for clinicians. And the presence of cognitive issues can make traditional treatments for depression, such as cognitive behavioral therapy (CBT), more difficult to practice.
Recently, a number of groups have worked to adjust CBT and related therapies to better suit those suffering from both dementia and depression. One is called Problem Adaptation Therapy (or PATH) and focuses on solving tangible problems that fuel feelings of sadness and hopelessness, incorporating tools like checklists, calendars, signs and videos, to make it accessible for people with memory issues. Another, called the Peaceful Mind program, developed for patients with anxiety and dementia, simplifies traditional cognitive behavioral therapy.

Here are links to five media articles on depression and dementia:
How are depression and dementia related?
Alzheimer’s or depression: Could it be both?
Depression | Alzheimer’s Association
New Therapies Help Patients With Dementia Cope With Depression
Cognitive behavior therapy for anxiety in people with dementia: a clinician guideline for a person-centered approach.

Here are three research articles dealing with Problem Adaptation Therapy (PATH) therapy:
Problem Adaptation Therapy for Older Adults With Major Depression and Cognitive Impairment
Problem Adaptation Therapy (PATH) for Older Adults with Major Depression and Cognitive Impairment: A Randomized Clinical Trial
Home-Delivered Problem Adaptation Therapy (PATH) for Depressed, Cognitively Impaired, Disabled Elders: A Preliminary Study

All links have been added to Neuro-Psych.

Ageotypes: Different Ways of Aging At The Molecular Level

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How bodies age differently has been explored using broad tools and large participant populations in the past. Recently, a small-scale more refined study has been reported, focusing on molecular aspects of aging. The study utilized 106 healthy participants (female & male) from 29 to 75 years of age, and used blood, stool and other biological samples, to track participants’ levels of certain microbes and biological molecules, such as proteins, metabolites and lipids, over 2-3 years, monitoring how the levels changed over time, and how they correlated with age. Based on the findings, the study defined different types of aging patterns in different individuals, termed ‘ageotypes’, on the basis of the types of molecular pathways that changed over time in a given individual. In particular, they identified four well-defined ageotypes: metabolic (buildup and breakdown of substances in the body), immune (immune system responses), hepatic (liver function) and nephrotic (kidney function), which can overlap, or be exclusive. It is expected that ongoing research will identify and characterize further ageotypes, and that the use of ageotypes will assist individuals in zeroing in on health-risk factors and find the areas in which they’re most likely to encounter problems as they age.

Here are links to three media articles on the work:
Scientists Discover 4 Distinct Patterns of Aging
‘Ageotypes’ provide window into how individuals age
Ageotypes: Why do people age differently?

Here is a link to the research study:
Personal aging markers and ageotypes revealed by deep longitudinal profiling

All links have been added to Aging

Category: Aging

Exercise, Aging & Inflammation

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Inflamm-aging (aka inflammaging or inflamm-ageing) is a chronic low-grade inflammation developing with advanced age, contributing to biological aging and worsening the course of Alzheimer’s disease, atherosclerosis, type II diabetes and chronic heart diseases. Earlier studies have indicated that exercise is useful in resisting such inflammation, and a new study of lifelong active athletes reinforces those studies. Note that inflammation is a normal body process, dealing with invading microbes as well as physical stress (including exercise). But when microbes are have been dealt with, or when exercise/stress concludes, inflammation should decrease to a normal base level. The chronic inflammation associated with aging remains above that normal base level.

At the beginning of the present study, two things were already known: 1) higher levels of inflammatory factors in people are associated with greater loss of muscle mass, and 2) physically fit people tend to have lower levels of inflammation in their bodies than inactive people. So the question was: do older, active people also have more and healthier muscle mass than other less active older people? This first study focused on men — another study on women is to be published soon.

This study enrolled 21 elderly athletic men, 10 healthy but sedentary elderly men, and 10 runners and cyclists in their 20s, none of whom had been performing weight training. The initial measurements taken focused on blood (for measuring inflammation levels) and thighs: their size at outset of the study, and the quality of their front (quadriceps) muscle as determined by biopsies. Immediately, the following was evident:

Group Thigh Size
Young Men Largest
Elderly Athletes Middle
Elderly Inactive Smallest

The experimental activity consisted of lower-body weight lifting, which would stress the thighs of all of the participants. After the weight-lifting, blood samples and biopsies were again drawn and examined for signs of both flaring of inflammation, together with signs of counter-inflammation activity, as shown here:

Group Inflammation Level Anti-Inflammation Activity

Young Men Smallest Greatest
Elderly Athletes Middle Middle
Elderly Inactive Largest Smallest

While being a lifelong athlete is obviously protective of one’s muscles, starting at middle age to go to the gym, or run, or cycle can gradually build up missing mass. And those aches and pains at first are the signs of inflammation, and their decline are the signs of the decline of inflammation.

Here are links to three media articles on the work:
25 Again? How Exercise May Fight Aging
Lifelong Exercise Prevents “Inflammaging”
LIFELONG EXERCISE PROTECTS AGAINST AGING

And here is a link to the research publication:
Effects of aging and lifelong aerobic exercise on basal and exercise-induced inflammation

All links have been added to Aging and Health > Physical Exercise

Listen Up! Hearing Aids Can Help Resist Dementia.

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In an October post (Hearing Loss and Dementia) we examined several studies of the relationship between hearing loss and the onset of dementia. The present post is a follow-up to that October post. We list three additional studies of the dementia-hearing loss relationship, together with seven media articles on that relationship, and on the ability of hearing aids to slow the possible onset of dementia due to hearing loss.

Here are the seven media articles:
For Better Brain Health, Preserve Your Hearing
Link between hearing and cognition begins earlier than once thought
Mild Hearing Loss May Be Associated with Mental Decline in Seniors
Hearing Loss Linked to Dementia
CAN HEARING AIDS HELP PREVENT DEMENTIA?
Cognitive loss and hearing loss
Hearing Loss and Dementia: Breakthrough Research Seeks Causal Link

Here are the three studies on the association of hearing losss with dementia:
Association of Subclinical Hearing Loss With Cognitive Performance.
Association of Hearing Loss With Dementia
Relationship of Hearing loss and Dementia: a Prospective, Population-based Study

All links have been added to Aging and Risk Factors.

Alzheimer’s And Sleep

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A recent study suggests a connection between the slow waves of deep sleep and a cleaning process likely clearly some of the accumulation of brain toxins, include beta-amyloid. So it is recommended that aging people try to sleep as healthy as possible.

Here are links to three media articles about the work:
How Deep Sleep May Help The Brain Clear Alzheimer’s Toxins
Scientists Now Know How Sleep Cleans Toxins From the Brain
Sleep may trigger rhythmic power washing in the brain

And here is a link to the research study:
Coupled electrophysiological, hemodynamic, and cerebrospinal fluid oscillations in human sleep

All links have been added to Neuro-Psych

Robot Pets for Dementia

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While dementia assistance dogs (Dogs And Dementia) are growing in use and popularity, live pets are not always possible or appropriate for many sufferers of dementia. In recent years, a number of companies have brought to market animatronic (preset moves and prerecorded sounds) and robotic (supporting more complex tasks) “pets” for use with dementia patients. Principally these “pets” are dogs, some cats, and even a harp seal. They can be held, petted, and brushed by dementia patients, and can produce some sounds and motion. Studies (see below) have shown that use of the robotic pets can reduce the stress and anxiety often suffered by dementia patients, and reports indicate that some patients develop emotional bonds with the pets.

Here are five media articles about the developments:
Therapy Cats for Dementia Patients, Batteries Included
Robotic pets delight patients with dementia
Robotic Pets To The Rescue? Dementia Care Gets Innovative
Is this robotic therapy pet the uncanny valley of dog?
The Second Coming of the Robot Pet

And here are a number of research articles on the use of robot pets for dementia intervention:
Pet robot intervention for people with dementia: A systematic review and meta-analysis of randomized controlled trials.
The Utilization of Robotic Pets in Dementia Care.
How do “robopets” impact the health and well‐being of residents in care homes? A systematic review of qualitative and quantitative evidence
Effect of an interactive therapeutic robotic animal on engagement, mood states, agitation and psychotropic drug use in people with dementia: a cluster-randomised controlled trial protocol
Use of a Robotic Seal as a Therapeutic Tool to Improve Dementia Symptoms: A Cluster-Randomized Controlled Trial
Robotic Pets: A Senior’s Best Friend?

All links have been added to Alzheimers > Coping & Caregivers > Dementia Assist Dogs & Robot Pets

Dogs And Dementia

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While the use of dogs as guide dogs (“seeing-eye dogs”) began in the aftermath of World War I, the last 40 years has seen the extension of service dog training into such areas as:

More recently, the last several decades have seen the development of dementia-assist dogs. Like all other therapy dogs, these dogs provide companionship and friendship for their owner. Additionaly, various trainers teach dogs a range of different behaviors, such as:

  • Since dementia patients often become agitated, some dogs are trained to interrupt this behavior by distracting their owner, and thus help reduce the owner’s anxiety and help them refocus;
  • Walk on a leash with the owner. If the owner gives the command “Home”, the dog will lead the owner back home. The dog’s collar will have a GPS device, which will allow caregivers to locate the pair if they get lost, or if the dementia patient forgets to issue the “Home” command;
  • Fetch a patient’s medication;
  • Waking their owner up each morning;
  • Trigger an alarm in the house if the patient falls and does not get up within a reasonable amount of time, or if the dog hears a choking sound.

The breeds used most often for service dogs are Labrador Retrievers, Golden Retrievers, Labrador/Golden Retriever crosses, and German Shepherds.

Here are links to several media articles about dementia-assist dogs:
The New Breed of Service Dog: Canine Caregivers for Dementia and Alzheimer’s Patients
Good Dogs: Dementia Service Dogs Provide Patients, Caregivers With Improved Quality of Life
Dementia Assistance Dogs
Assistance Dogs for Alzheimer’s and Dementia Patients

Here is one study of how use of a therapy dog can affect the quality of life of an Alzheimer’s sufferer:
Stepping out of the shadows of Alzheimer’s disease: a phenomenological hermeneutic study of older people with Alzheimer’s disease caring for a therapy dog

Here is a review of six studies (between 2016 – 2018) of the effectiveness of animal assisted therapy (AAT) with special focus on dog therapy among people with dementia, and in particular, Alzheimer’s disease:
Effectiveness of the dog therapy for patients with dementia – a systematic review

All links have been added to Alzheimers > Coping & Caregivers > Dementia Assist Dogs & Robot Pets