Dementia Flashcards
define dementia
syndrome due to a disease of the brain usually chronic and progressive present for more than 6 months
what functions of the brain can be affected in dementia?
multiple higher cortical functions including memory, thinking, orientation comprehension, learning capicty, language and judgment
ESPECIALLY:
o Memory - especially learning and retrieval of new info
o Cognitive abilities - deterioration in judgement, thinking and language
o Emotional control - emotional lability, apathy, irritability, wandering, disinhibition
if you suspect dementia but there is clouding of consciousness, what is it?
delerium
what are the differentials for dementia?
D rugs/delirium E motions/depression (pseudodementia) M etabolic disorder (glucose or thyroid) E eye/ear problems (e.g. deafness) N utritional disorders (e.g. B12/folate deficiency) T umours, toxins, trauma I nfections A lcohol, arteriosclerosis
In what order do you get symptoms in alzheimers?
memory loss impaired thinking language impairment deterioration in personal functioning disturbed personality and behaviour perceptual abnormalities motor impairments
How is memory affected in alzheimers?
short-term > long-term
leads to impaired learning and disorientation (time first, then place and person)
How is thinking impaired in alzheimers?
poor judgement, decreased fluency, concrete thinking and impaired abstraction, lack of ability to plan, delusions
how is language impaired in alzheimers?
expressive and receptive aphasia and dysphasia
how is personal functioning affected in alzheimers?
deterioration in occupational and social functioning and AoDL/ self-care
how is personality and behaviour affected in alzheimers?
euphoria and lability or apathy and irritability. disinhibition which can lead to aggressive and inappropriate behaviour, inattention and distractibility, obsessive and stereotyped behaviours.
How are perceptions altered in alzheimers?
visual and auditory agnosia, visuospatial difficulties, body hemineglect, prosopagnosia (can’t recognise faces), illusions, hallucinations, cortical blindness
how is the motor function altered in alzheimers?
Apraxia, spastic paresis, urinary incontinence
What are primary causes of dementia?
Alzheimer’s disease (most common)
Dementia with Lewy bodies and PD
Pick’s disease and other frontotemporal dementias
Huntington’s disease
what are secondary causes of dementia?
Vascular Infective (AIDs, lyme disease) Inflammatory (SLE) Neoplastic Metabolic (cardiac, hepatic and renal failure) Endocrine (thyroid) Toxic (alcohol) Traumatic
What investigations should you do in dementia?
- A physical examination should be carried out to identify any underlying causes of dementia and any complications of dementia such as malnutrition, burns, or falls.
- Baseline bloods as standard. Other investigations on case by case basis
- Detailed neurocognitive testing by a clinical psychologist can be helpful in identifying cognitive impairments and in confirming a diagnosis.
- Dr Ostler scans anyone under 75 or if something Hx raises a question MRI/CT and can use PET scan
What neurocognitive testing can you do?
o MMSE/AMTS/MOCA for screening and monitoring
MMSE <24 = suggestive of dementia
Only need to know AMTS!
o Addenbrooke’s Cognitive Exam (ACE – III) is what they use in memory clinics (<88/100)
What blood tests should you do in a confusion screen and why?
• FBC
o Infection, anaemia, increased MCV (macrocytic anaemia caused by B12/folate deficiency)
• LFTs
o Liver failure, alcohol abuse
• U&Es
o Kidney failure can cause cognitive impairment?
• INR
o If on warfarin and concerned about bleeds from fall/head injury
• TFTs
o Confusion more common in hypothyroid states
• Calcium
o Hypercalcaemia can cause confusion/delirium (bones, moans, psychotic groans
• B12/folate can cause confusion (alcohol use, leukaemias, dietary deficiency/ malabsorption)
• Glucose
o Hypoglycaemia = common cause of confusion
• Syphilis
o Not often necessary, rare but overlooked
• HIV
o Dementia common in AIDS
what other investigations should you do in a confusion screen?
CT HEAD – stroke, lesion, bleeds from fall/trauma, cerebral atrophy, widening of the sulci or gyri, dilated ventricles (could be hydrocephalus), atrophy of medial temporal lobe in Alzheimer’s
(MRI recommended by NICE but CT usually sufficient)
CXR – as part of sepsis screen – rule out pneumonia, bronchial CA w/cerebral mets
BLOOD CULTURES – if appropriate
URINE DIPSTICK/CULTURE – v common cause in elderly, but positive dipstick w/o clinical signs is not enough to diagnose urosepsis as a cause of delirium (look this up)
URINE DRUG TEST – if illicit drugs considered possible cause of confusion/psychosis
EEG – characteristic 3Hz ‘spike and wave’ in prion disease
LP – normal pressure hydrocephalus, herpes encephalitis
What is the very general management in dementia?
- Secondary dementias may be reversible
- But usually aim of management is to improve/maintain QOL for patient and carer(s).
- This involves treating the SYMPTOMS AND COMPLICATIONS of dementia, addressing FUNCTIONAL problems, addressing SOCIAL problems, and providing EDUCATION and SUPPORT for carers.
What are important considerations in the MDT approach in treating dementia? (general info)
• Personal hygiene & nutrition
• Functional abilities can be maintained and even improved by a regular daily routine, environmental modifications, and graded assistance.
• The patient should be reoriented and reassured, and encouraged to partake in physical and mental activity.
• Memory aids such as clocks, calendars, notebooks, and photographs, and reality orientation and reminiscence therapies may also be helpful, particularly in the early stages of the disease.
• To aid sleep, sleep hygiene, Horlicks or milky drinks, sedation at night, sedative antidepressants e.g. trazadone (may increase risk of falls), change to another AChEi, try NDMA blocker e.g. memantine.
• Telecare to stop wandering.
• If dementia is diagnosed must inform DVLA
• Social problems:
o Isolation, accommodation (?specialist home)
o Financial/legal matters e.g. power of attorney
• Carer education and support
What classes of drug can you use in dementia?
Acetylcholinesterase inhibitors
NMDA receptor antagonist (memantine)
Other possible drugs (use sparingly and infrequently - benzos, SSRIs, Antipsychotics (quetiapine)
Whats the most common cause of dementia?
• AD = most common cause of dementia - over 50% of all cases (850,000 people in UK)
what is the neuropathology of alzheimers?
• Selective neuronal and synaptic loss leads to neurochemical abnormalities (notably decreased ACh) and symmetrical cortical atrophy that is initially more pronounced in the medial temporal and parietal lobes.
• Extracellular senile plaques and intracellular neurofibrillary tangles are seen in normal ageing, but they are more numerous in AD and they are closely related to the degree of cognitive impairment.
• Senile plaques consist of a core of beta-amyloid surrounded by filamentous material.
• Neurofibrillary tangles consist of coiled filaments of abnormally phosphorylated microtubule-associated protein tau (note that tau is also found in Pick bodies)
• Decreased ACh
o Due to degeneration of the cholinergic neurons of the basal forebrain
• Other histopathological findings include glial proliferation, granulovascular degeneration, and Hirano inclusion bodies (intracellular aggregates of actin).
What are risk factors for alzheimers?
Age Female sex (2:1) FH Down’s syndrome Head injury Dialysis (aluminium containing dialysis fluids)
what are protective factors for alzheimers?
Healthy and engaged lifestyle High educational achievement (does this just delay diagnosis? NSAIDs HRT Vit C Vit E Statins
what is the genetic link in alzheimers?
• E4 allele of apolipoprotein E
o Chromosome 19
o Risk factor for common, sporadic, late-onset form
• E2 is protective
• APP (amyloid precursor protein) mutations
o Chromosome 21
o AD inherited, early onset
• PSEN1/PSEN2 also associated with familial presenile dementia
