Cognitive impairment Flashcards
Definition of dementia
Acquired progressive generalised impairment in cognition that interferes with social functioning but without clouding of consciousness
Cardinal clinical features of dementia
- Memory impairment (short term > long term)
- Behaviour: Restless, repetitive/purposeless, rigid routine
- Speech: Dysphasia, mutism
- Mood: Irritable, depressed
- Peronsality: Disinhibition, aggression
- Lack of insight
- Psychosis (esp visual hallucinations) in 50% of cases
- Progressive
Differentials for dementia
- Deafness/dysphasia: Check they can hear
- Depression: Important and reversible
- Delirium: Associated with organic pathology
- Drugs: esp anticholinergics
- Epilepsy: Post-ictal state, ongoing complex partial seizures (temporal lobe epilepsy)
Distinguishing dementia from depression (pseudodementia)
- Did low mood (or other features of old age depression) precede memory impairment
- Is failure to answer Qs due to lack of ability or lack of motivation? (I don’t know/it’s too hard vs incorrect answer)
- Neurological deficits suggest organic cause (e.g. dementia)
Prominent features of depression in older adults (> than low mood)
Apathy
Anxiety
Forgetfulness
Irritability
Broad categories of dementia aetiologies
Common dementias
Degenerative disorders
Metabolic disorders
Infections
Neurological disorders
Most common causes of dementia
Alzheimer’s: 50-60% of cases
Vascular dementia: 20-25%
Dementia with Lewy bodies: 10-15%
Everything else: 10%
Degenerative disorders causing dementias (in the 10%)
Frontotemporal degeneration
Huntington’s
Parkinson’s plus syndromes
Prion disease (e.g. CJD)
Metabolic/endocrine abnormalities causing cognitive impairment
Hypothyroidism
Hyperparathyroidism
Hypercalcaemia
B12/folate deficiency
Alcohol-associated dementia
Cushing’s
Infections causing dementia
HIV
Syphilis
Meningitis/encephalitis may present as cognitive impairment (more commonly delirium)
Neurological causes of dementia
Head injury
Subdural haematoma
Intracranial tumour/mets
Normal pressure hydrocephalus
Dementia suggested by past history of fall
Subdural haematoma
Dementia suggested by repeated falls
Lewy body dementia
Progressive supranuclear palsy
Dementia suggested by carotid bruits/hypertension
Vascular dementia
Dementia suggested by incontinence
Normal pressure hydrocephalus
Delirium
Dementia suggested by prominent behavioural change/apathy early in illness
Vascular dementia
FTD
Dementia suggested by prominent aphasia early in illness
Vascular dementia
FTD
Dementia suggested by progressive gait disorder
PD-assoc dementia
normal pressure hydrocephalus
Vascular dementia
Dementia suggested by prominent fluctuations
Lewy body
Delirium
Medication SEs
Obstructive sleep apnoea syndrome
Dementia suggested by hallucinations or delusions
Delirium
Medication SEs
Late-onset schizophrenia (paraphrenia)
Dementia with Lewy bodies
Dementia suggested by eye movement abnormalities
PD-assoc dementia
Wernicke’s encephalopathy
Formal assessment tools for cognition
MMSE
MOCA
CLOX
Addenbrookes Cognitive Examination
Prominent symptoms and signs of Alzheimer’s dementia
Memory loss
Dyspraxia
Dysphasia
Apathy
Psychosis
Loss of executive f(x): disorganisation, disorientation, lack of reasoning
Prominent symptoms and signs of vascular dementia
Gait disturbance (Parkinsonian, small-step)
Urinary urgency/frequency appears early
Preserved insight
Labile mood, personality changes (occur earlier than AD, before memory)
Sudden-onset, step-wise progression
Hx/risk factors for vascular disease
Prominent signs and symptoms of LB/Parkinsonian dementia
Parkinsonism
Visual hallucinations (usually not scary)
Flucctuating dementia
Delirium-like phases
Poor REM sleep
Visuospatial impairment
Prominent signs and symptoms of frontotemporal dementia
Early onset (40-60)
Insidious, gradual progression (lacks insight)
Memory initially preserved
Early primitive reflexes + stereotyped behaviours
Peronsality change
Emotional blunting
Expressive dysphasia: echolalia, perseveration, reduced speech
Prominent features of Huntington’s disease
Family Hx
Early onset (20s-40s)
Choreiform movements
Irritability/depression
Schizophrenia-like psychosis
Prominent features of normal pressure hydrocephalus
Urinary incontinence
Gait apraxia
Mental slowing, apathy, inattention
Onset 50-70s
Clinical features of prion disease
Onset <50
Myoclonic jerks
Seizures
Cerebellar ataxia