Neurodegenerative Diseases of CNS

Question 1

Dementia Definition

Answer 1

SYNDROME CONSISITING OF:

PROGRESSIVE IMPAIRMENT OF MULTIPLE DOMAINS OF COGNITIVE FUNCTION

IN ALERT PT.

LEADING TO LOSS OF ACQUIRED SKILLS & INTERFERENCE IN OCCUPATION & SOCIAL ROLE

DUE TO COGNITIVE DEFICIT - NOT MOTOR DEFICIT

Question 2

Risk Factors of Dementia

Answer 2

AGEING (> 60yrs; starts rlly picking up ~ 80yrs)

Question 3

Causes of Dementia (late onset & early onset)

Answer 3

LATE ONSET:

• ALZHEIMER’S (55%)
• VASCULAR (20%)
• LEWY BODY (20%)
  
  • PARKINSONISM
• OTHERS (5%)

YOUNG ONSET:

• ALZHEIMER’S (33%)
• VASCULAR (15%)
• FRONTOTEMPORAL (15%)
• OTHER (33%)
  
  • TOXIC = ALCOHOL
  • GENETIC = HUNTINGTON’S○ ABNORMAL MOVEMENTS
  • INFECTION = HIV, CJD

    ○ CJD = RAPID PROGRESSION + MYOCLONUS

  • INFLAMMATORY = MS

Question 4

Treatable causes of Dementia

Answer 4

VITAMIN DEFICIENCY = B12

ENDOCRINE = THYROID DISEASE

INFECTIVE = HIV, SYPHILIS

MIMICS (don’t fulfil criteria of dementia):

HYDROCEPHALUS, TUMOUR, DEPRESSION (PSEUDODEMENTIA)

Question 5

Dementia Investigations

Answer 5

CLINICAL DIAGNOSIS (progressive cognitive deficit, evidence of loss of ability to do normal day-to-day things due to cognitive deficit)

RELIABLE HISTORY (what are they struggling with, progression, risk factors, FH)

EXAMINATION (COGNITIVE FUNCTION, NEUROLOGICAL, VASCULAR)

Cognitive function:

Memory, attention, language, visuospatial
Behaviour, emotion, executive function
Apraxias, agnosias

SCREENING TESTS: MINI-MENTAL (MMSE), MONTREAL (MOCA)

NEUROPSYCHOLOGICAL ASSESSMENT

ROUTINE: BLOODS, CT/MRI

OTHERS: CSF, EEG, FUNCTIONAL IMAGING, GENETICS, BIOPSY

Question 6

Dementia Management (symptomatic)

Answer 6

NON-PHARMACOLOGICAL:

• INFO + SUPPORT, DEMENTIA SERVICES
• OCCUPATIONAL THERAPY
• SOCIAL WORK/SUPPORT/RESPITE/PLACEMENT
• VOLUNTARY ORGANISATIONS

PHARMACOLOGICAL:

• INSOMNIA
• BEHAVIOUR (care w/ antipsychotics)
• DEPRESSION

Question 7

Dementia Management (specific)

Answer 7

ALZHEIMER’S (± LEWY BODY DEMENTIA):

• CHOLINESTERASE INHIBITORS (cholinergic deficit)
  
  • DONEPEZIL, RIVASTIGMINE, GALANTAMINE
  • Small symptomatic improvement in cognition, but no delay in institutionalisation
• NMDA ANTAGONIST = MEMANTINE

FRONTOTEMPORAL = NONE

VASCULAR DEMENTIA = NO GOOD EVIDENCE IN REDUCING VASCULAR RISK FACTORS

Question 8

Types of Dementia

Answer 8

ALZHEIMER’S:

MEAN AGE ONSET = 70YRS

• TEMPORO-PARIETAL DEMENTIA:

* EARLY MEMORY DISTURBANCE
* LANGUAGE & VISUOSPATIAL PROBLEMS
* PERSONALITY PRESERVED UNTIL LATER

FRONTOTEMPORAL:

• EARLY CHANGE IN PERSONALITY/BEHAVIOUR
  
  • OFTEN CHANGE IN EATING HABITS
• EARLY DYSPHASIA
• MEMORY/VISUOSPATIAL RELATIVELY PRESERVED

VASCULAR:

• STEPWISE DECLINE + MIXED PICTURE
  
  • Depends on location of vascular hits
  • May have peripheral vascular disease, CV disease etc.

Question 9

Parkinson’s Definition

Answer 9

CLINICAL SYNDROME W/ ≥ 2 of:

BRADYKINESIA (slowness of movements)
RIGIDITY (stiffness)
TREMOR (shakiness)
POSTURAL INSTABILITY (unsteadiness/falls)

Question 10

Pathology of Parkinson’s

Answer 10

LOSS OF DOPAMINERGIC NEURONS IN BASAL GANGLIA

Question 11

Risk Factors of Parkinson’s

Answer 11

AGEING (> 60yrs); MORE MALES (~1.5x more)

Question 12

Aetiology of Parkinson’s

Answer 12

IDIOPATHIC PARKINSON’S DISEASE = DEMENTIA W/ LEWY BODIES

DRUG-INDUCED = e.g. dopamine antagonists, sodium valproate

VASCULAR PARKINSONISM = lower 1/2

PARKINSON’S PLUS SYNDROMES:

○ MULTIPLE SYSTEM ATROPHY (incontinence, sexual dysfunction etc.)

○ PROGRESSIVE SUPRANUCLEAR PALSY/CORTICOBASAL DEGENERATION

Question 13

Parkinson’s Investigations

Answer 13

COMPLETE HISTORY + EXAMINATION = LOOK FOR ABOVE SIGNS + POSS. AETIOLOGY

FUNCTIONAL IMAGING: DOPAMINE TRANSPORTER SPECT

Question 14

Clinical Diagnosis of Parkinson’s (+ what makes it less likely)

Answer 14

BRADYKINESIA + ≥ 1 TREMOR, RIGIDITY, POSTURAL INSTABILITY

NO OTHER CAUSE/ATYPICAL FEATURES

SLOWLY PROGRESSIVE (> 5-10yrs)

Supported by ASYMMETRIC TREMOR, GOOD RESPONSE TO DOPAMINE REPLACEMENT TREATMENT

Less likely if:

RAPID PROGRESSION
SYMMETRICAL
LACK OF REST TREMOR
POOR RESPONSE TO TREATMNET
EARLY FALLS
EARLY DEMENTIA
OTHER ABNORMAL NEUROLOGICAL SIGNS

Question 15

Parkinson’s Management:

Answer 15

PHARMACOLOGY:

DA PRECURSOR = LEVODOPA

DOPAMINE AGONISTS:

NON-ERGOTS = ROPINIROLE, PRAMIPEXOLE (oral); ROTIGOTINE (transdermal patch)

APOMORPHINE (continuous s/c infusion)

ENZYME INHIBITORS:

PERIPHERAL AAAD INHIBITORS = CARBIDOPA, BENSERAZIDE

MAO-B INHIBITORS = SELEGILINE, RASAGILINE, SAFINAMIDE

COMT INHIBITORS = ENTACAPONE, TOLCAPONE

NON-PHARMACOLOGICAL:

FUNCTIONAL NEUROSURGERY = DEEP BRAIN STIMULATION

ALLIED HEALTH PROFESSIONALS = may have CARE PACKAGE

Question 16

Later Complications of Parkinson’s (drug-induced & non drug-induced)

Answer 16

DRUG INDUCED:

MOTOR FLUCTUATIONS - levodopa wears off

DYSKINESIAS (involuntary movements) - levodopa

PSYCHOSIS (hallucinations, abnormal behaviours, impulsivity) - too much dopamine

NON DRUG-INDUCED esp. NON-MOTOR:

DEPRESSION
DEMENTIA
AUTONOMIC: BP, BOWEL, BLADDER
SPEECH, SWALLOW
BALANCE

Question 17

Neurodegenerative Condition Presentation

Answer 17

LATE ONSET

GRADUAL PROGRESSION

NEURONAL LOSS

STRUCTURAL IMAGING NORMAL