Module 52 (Degenerative Disorders)

Question 1

Dementia

Answer 1

-an umbrella term that refers to gradual deterioration of cognitive functioning
-a decline in mental ability that interferes with daily life
-Deterioration in memory, language, judgment, and decision making, among cognitive functions
-Dementia has various causes and may be irreversible

Question 2

Causes of Dementia

Answer 2

-Dementia has various causes and may be irreversible
-Vascular dementia
-dementia with lewy bodies
-parkinson’s dementia
-frontotemporal dementia

Question 3

Alzheimer Disease

Answer 3

-a brain disorder that progressively destroys memory and thinking abilities
-a progressive neurodegenerative disorder characterized by an accumulation of pathological biomarkers, including amyloid-beta plaques and tau protein tangles that disrupt neuron communication and lead to cell death
-Symptoms typically appear in the mid 60s but can also start to appear later in ones 80s
-Symptoms can also occur between the mid 30-60s however this is rare

Question 4

Alzheimer prevalence

Answer 4

Approximately 5-6 million people in US

Question 5

Neurodegenerative Disorders

Answer 5

-an umbrella term that refers to a range of disorders characterized by neuron loss
-Neurons are essential to maintain proper brain functioning as they play a role in communication

Question 6

Neurodegeneration

Answer 6

-the progressive loss of neurons, neuron structure, and their functions
-When neurons degenerate, they may have problems at their connections (synapses), the networks they form might not work correctly, and the abnormal proteins can accumulate in the brain

Question 7

Biomarkers

Answer 7

-biological clues that scientists and doctors use to detect diseases in the body, even before symptoms show up
-Biomarkers help detect the disease’s presence, predict disease progression, and assess responses to treatments
-Biomarkers allow us to detect and monitor diseases in vivo (while person is still alive)
-Traditionally, diagnoses could only be confirmed through post-mortem neuropathological examination of brain tissue, based on the presence of amyloid plaques and tau tangles

Question 8

Biomarkers for Alzheimer Disease

Answer 8

Amyloid-beta, Tau protein, and Neurodegeneration (ATN)

Question 9

Amyloid-beta (plaque)

Answer 9

a sticky protein called amyloid-beta builds up in the brain and forms clumps called plaques, which are a key feature of AD

Question 10

Tau protein (tangles)

Answer 10

another protein called tau gets tangled inside brain cells, disrupting their ability to function. Tau tangles are another key feature of AD

Question 11

How do we detect Biomarkers in AD?

Answer 11

-Position Emission Tomography (PET)
-Magnetic Resonance Imaging (MRI)
-Cerebrospinal Fluid (CSF)

Question 12

Position Emission Tomography (PET)

Answer 12

a PET scan is like a specialized camera that can detect specific proteins or activity inside your brain using a safe small dose of radioactive dye
-includes Amyloid PET and Tau PET

Question 13

Amyloid PET

Answer 13

detects amyloid plaques, the dye sticks to amyloid, lighting it up on the scan

Question 14

Tau PET

Answer 14

detects tau tangles, the dye sticks to tau tangles, lighting them up on the scan

Question 15

Magnetic Resonance Imaging (MRI)

Answer 15

-uses powerful magnets and radio waves (no radiation) to create detailed pictures of the brain’s structure
-Shows shrinkage in the brain
-In AD, certain areas like the hippocampus (important for memory) get smaller because brain cells are dying

Question 16

Cerebrospinal fluid (CSF)

Answer 16

-the clear fluid that surrounds your brain and spinal cord, like a protective cushion
-We can detect presence of amyloid and tau in CSF fluid

Question 17

Types of Alzheimer Disease

Answer 17

Late-Onset, Early-Onset, Autosomal Dominant (familial), down syndrome

Question 18

Late-Onset Alzheimer’s

Answer 18

-“typical” AD with amnestic presentation (memory loss)
-Greatest risk factors are age and Apolipoprotein E4 allele
-Most common form of the disease

Question 19

Early-Onset Alzheimer’s

Answer 19

amnestic, but also atypical visual and language presentations

Question 20

Autosomal Dominant (familial)

Answer 20

-mutations in PSEN1, PSEN2, and APP
-Early onset (40s and 50s)
-Rare: <50,000 people in the US

Question 21

Down Syndrome

Answer 21

-triplication in chromosome 21 leads to repeat in APP
-By age 40, almost all people with Down Syndrome have brain changes associated with Alzheimer’s disease, but symptoms may not develop until later
-50% or more of people with Down Syndrome will develop Alzheimer’s Disease

Question 22

Modifiable Risk Factors and brain health

Answer 22

Lifestyle, depression, infections, dyslipidemia, hypertension/cardiovascular disease, head injuries, sleep disturbances, type 2 diabetes, smoking, stress/genetic, midlife obesity