Dementia and Epilepsy

Question 1

Define dementia

Answer 1

• Dementia is the progressive decline in higher cortical function leading to a global impairment of memory, intellect and personality which effects the individuals ability to cope with activities of daily living
• Neuronal degeneration throughout cortex

Question 2

State the major causes of dementia

Answer 2

• Alzheimer’s Disease
• Vascular dementia
• Dementia with Lewy-Bodies
• Fronto-temporal dementia

Question 3

State the reversible causes of dementia

Answer 3

• Depression
• Trauma
• Vitamin deficiency
• Alcohol
• Thyroid disorders

Question 4

Describe the presentation of dementia

Answer 4

• Presentation depends on area of brain which is affected
• Memory deficit- struggle to learn new information, short term memory loss
• Behavioural - altered personality, disinhibition, labile emotions, wandering
• Physical - incontinence, reduced oral intake, difficulty swallowing
• Language disorder - anomic aphasia (cannot express words they want to say), difficulty understanding language
• Visuospatial disorder - unable to identify visual and spatial relationships between objects
• Apraxia - difficulty with motor planning resulting in inability to perform learned purposeful movements
  - Getting dressed, driving

Question 5

Describe the investigations for dementia

Answer 5

• Full history and MMSE (mini-mental state examination)
  
  • Assess cognitive baseline and rate of progression
  • Take collateral history from family
• Full neurological examination
• Blood tests - for reversible causes (thyroid function tests, vitamin B12)
• CT/MRI head - rule out other differential diagnosis
  
  • Dementia CT scan shows dilated ventricles and generalised cortical-matter atrophy
  • Dementia MRI scan can better picture the atrophy
• Memory clinic follow up

Question 6

Define delirium

Answer 6

Delirium is an acute onset of mental confusion due to a stimulus (infection, UTI, constipation)

Question 7

Describe how to assess and monitor delirium

Answer 7

• Use CAM score (confusion assessment method) where 2+ shows delirium
• Acute change or fluctuating mental status
• Altered consciousness - hypoactive (isolating)/hyperactive (agitated, distressed)
• Inattention - ask patients to count from 20 to 1
• Disorganised thinking - flocking from 1 idea to another

Question 8

Describe the rate of progression of cognitive decline in the major causes of dementia

Answer 8

• Vascular dementia - stepwise decline whereby a vascular event causes significant decline
• Alzheimer’s - gradual steady decline
• Lewy body dementia - general downward trend with times of improvement

Question 9

Describe the macroscopic and microscopic appearance of Alzheimer’s disease

Answer 9

• Loss of cortical and subcortical white matter causing gyral atrophy with narrow gyri and wide sulci along with marked ventricular dilation reflecting loss of white matter
  
  • Neuronal degeneration
• Microscopic pathology
  
  • Amyloid-beta plaques
    
    • Proteolytic breakdown of amyloid precursor protein to amyloid-ß peptides occurs in all people, however breakdown faster in Alzheimer’s
    • Neurofibrillary (tau) tangles

Question 10

Describe the stages of Alzheimer’s disease and its associated symptoms

Answer 10

• Mild - lasts 2-4 years
  
  • Minor memory loss as well as difficulty learning and remembering new information
  • Long term memory and reasoning remain intact
• Moderate - lasts 2-10 years
  
  • Patient experiences withdrawal, confusion, increasing difficulty in self care and daily tasks, poor judgement and difficulty communicating
  • Behavioural changes often include anger, anxiety, frustration and restlessness
  • Caregiver assistance becomes increasingly necessary
• Severe - lasts 1-3 years
  
  • Patients are completely incapacitated, retreat into themselves and will not eat unless fed
  • Patients may not speak and do not recognize people, even family members
  • Loss of bodily function control (swallowing, bladder, bowel)
  • Violent episodes and aggression are common

Question 11

Describe the pathology of Lewy body dementia

Answer 11

• Lewy bodies in the cortex and substantia nigra
• Differs from Parkinson’s where lewy bodies are only found in substantia nigra
• Dopamine agonist treatment does not work for Lewy body dementia

Question 12

Describe the clinical features of lewy body dementia

Answer 12

• Substantial fluctuations in the degree of cognitive impairment over time
• Parkinson’s symptoms - bradykinesia, resting tremors, rigidity etc
• Visual hallucinations
• Frequent falls

Question 13

Describe the pathology of vascular dementia

Answer 13

• Abrupt, step-wise decline in cognitive function related to vascular episode
  
  • Commonly in stroke or TIA
• Pathology
  
  • Arteriosclerosis of the blood vessels supplying the brain
  • Results in decreased/cut off blood supply to specific part of brain

Question 14

Describe the management of vascular dementia

Answer 14

• Can be prevented/better treated compared to other dementia causes
• Assess cardiovascular risk - treat hypertension, hypercholesterolemia
• MRI scan needed if vascular dementia suspected

Question 15

Describe the pathology of frontotemporal dementia

Answer 15

• Frontotemporal lobar degeneration with tau pathology

- Pick’s disease - pick bodies

Question 16

Describe the clinical features of frontotemporal dementia

Answer 16

• Frontal lobe symptoms
• Alteration of social behaviour and personality - agitation, depression, language disorders, mood swings
• Impaired judgement and insight - gambling, taking off clothes, inappropriate comments
• Speech output eventually becomes mute

Question 17

Describe the management of dementia

Answer 17

• Holistic approach
• Therapies - aimed to improve mood of patients (pets, babies)
• Social care - risk assessment, care needs, mental capacity act
• Drugs - cholinesterase inhibitors aimed at mild/moderate Alzheimer’s
• Memory aids - orientation boards, remembrance therapy, life stories

Question 18

Describe how dementia leads to death

Answer 18

• Most patients die of medical complications - aspirating pneumonia, stroke due to immobility
• Difficulty swallowing and decreased appetite lead to weight loss - increased risk of infection
• Falls due to loss of body control and violent episodes

Question 19

Define seizure

Answer 19

A sudden irregular discharge of electrical activity in the brain causing a physical manifestation such as sensory disturbance, unconsciousness or convulsions

Question 20

Define convulsion

Answer 20

Uncontrolled shaking movements of the body due to rapid and repeated contraction and relaxation of muscles

Question 21

Define aura

Answer 21

• A perceptual disturbance experienced by some prior to a seizure
• Eg. Strange light, unpleasant smell, confusing thoughts

Question 22

Define epilepsy

Answer 22

Neurological disorder marked by sudden recurrent episodes of sensory disturbance, LOC or convulsions, associated with abnormal electrical activity in the brain

Question 23

Define status epilepticus

Answer 23

• Epileptic seizures occurring continuously without recovery or consciousness in between
• Cyanotic, needs management

Question 24

Differentiate between partial and generalised seizures

Answer 24

• Partial seizures affect a small part of brain while generalised seizures affect the entire brain
• Partial seizures divided into simple and complex
• Generalised seizures divided into absence, myoclonic, tonic-clonic, tonic, atonic

Question 25

Describe the subtypes of partial seizures

Answer 25

• Simple seizures cause no interruption to consciousness

- Complex seizures cause interruption to consciousness to varying degrees

Question 26

Describe examples of partial seizures

Answer 26

• Most commonly temporal lobe epilepsy
  
  • 1st/2nd decade in most people, following seizure with fever or an early injury to the brain
  • Auras - auditory hallucination, rush of memories
• Frontal lobe epilepsy
  - Abnormal movements when motor areas affected (contralateral side)

Question 27

Describe the subtypes of generalised seizures

Answer 27

• Tonic-clonic - tense muscles with convulsions - recurring
• Absence - sudden stop in action and then continue as if nothing happened
  
  • Eg. Stop in middle of conversation and then continue after 3 seconds
• Myoclonic - brief shock-like muscle jerks - not recurring
• Atonic - drop attack
  
  • Neck/limb drop, falls
• Tonic - increased muscle tone

Question 28

Describe the investigations for epilepsy

Answer 28

• Clinical history - take collateral history, especially to aid description during seizure and after
• EEG - not diagnostic but supports diagnosis
  
  • In first unprovoked seizure - assess risk of seizure recurrence
  • EEG may induce a seizure
    
    • Do not use if probable syncope (risk of false positive result), clinical presentation supports diagnosis of non-epileptic event, in isolation to make a diagnosis of epilepsy
• MRI - help exclude differential diagnosis - haemorrhage, tumour
• ECG - exclude syncope as diagnosis

Question 29

What other measures of EEG can you do if the first result is unclear

Answer 29

• Repeat standard EEG
• Sleep EEG
• Long term video or ambulatory EEG (electrodes attached and patients lives normal life while attached)

Question 30

Describe the management of epilepsy

Answer 30

• Benzodiazepines - lorazepam, midazolam
  
  • Pre-hospital - PR or buccal (in cheeks)
  • Hospital - IV
• Driving conditions
  
  • If epilepsy suffered while awake, licence taken away until 1 year seizure-free
  • If due to medication change, taken away until 6 months seizure-free