Midterm #2 (Lecture 13 - Multiple Sclerosis)

Question 1

How common is MS?

Answer 1

2.8 million people in the world with MS (1/3,000)

Question 2

Average age for diagnosis?

Answer 2

Worldwide = 32
Canada = 43
Diagnosis can occur in children and older adults

Question 3

Which people does MS favor?

Answer 3

More women than men (hormones)
- Pregnancy can actually help, but 1-3 months pp it gets worse (PP rebound)
US, Canada, Europe very high
Farther from equator, higher chance of MS
Alberta is the highest in the world

Question 4

What is MS?

Answer 4

Multiple = many sites of lesions
Sclerosis = hardened tissue/plaques in CNS
A chronic neurological disorder affecting CNS
Auto-immune condition – the immune system reacts to the myelin
Damage to myelin sheath, deteriorates axon, brain also affected

Question 5

What is myelin and what makes it?

Answer 5

Myelin – Lipids and proteins that wrap around axon
Oligodendrocytes – Produce myelin sheath

Question 6

What is the autoimmune part?

Answer 6

The autoimmune response causes Inflammation, destruction of oligodendrocytes, myelin and forms scar tissue
 Signals travel slower and may dissipate before reaching target
Eventual axonal loss because signals can’t make it through, axon isn’t used anymore

Question 7

Demyelination can occur on ________ and ________ pathways

Answer 7

Afferent (position, touch, pressure, pain)
Efferent (voluntary control of movement, bowel and bladder control)
Which is why symptoms vary so much

Question 8

Types of MS

Answer 8

Relapsing-remitting: most common, unpredictable attacks where we might get permanent deficits
Secondary progressive: ALWAYS diagnosed after relapsing-remiting, suddenly begins to get worse without periods of remission
Primary progressive: More severe, always getting worse, no break, less common
Progressive-relapsing: very rare, very severe, always getting worse plus attacks

Question 9

Symptoms of MS

Answer 9

Hidden, varied, mental and physical, INVISIBLE illness
FATIGUE very common
Balance/dizziness - affects walking
Bladder - not well-treated
Cognitive - (umbrella term) processing, attention, speech
Depression - 2-5x higher in MS, not well-treated
Gait - foot drop common, balance, muscle weakness, reduced proprioception
Optic neuritis - inflammation of optic nerve, early sign, blurring, blindspot, loss of colour
Pain - sensory overload, squished “MS hug”, very subjective, common
Uthoff’s phenomenon/heat intolerance - increase in symptoms when body temp goes up, but only temporary (no permanent damage)