Old Age Psychiatry Flashcards
How common is depression in older adults, what is it associated with
- 15% of older people, and 30% of older hospital inpatients are depressed at any time.
- Depression in later life may be associated with cerebrovascular disease, vascular RFs and current or future cognitive deficits
- Depression in older adults is also associated with bereavement, isolation, poverty, chronic pain, physical illness, and polypharmacy
How does a presentation of depression in older adults differ from younger patients
- Older people may present in a similar way to younger people, but may show: physical symptoms (constipation, insomnia, fatigue), psychomotor agitation/ retardation, memory problems, executive dysfunction. Suicidal ideation should be taken very seriously (high completion %)
- Pseudodementia occurs where depression mimics dementia
What is the prevalence of anxiety disorders and psychosis in old age
- The prevalence and incidence of anxiety disorders fall with age, possibly due to under-reporting. They are more common in women and isolated people.
- Many people with psychosis first become unwell in their youth, however, functional psychosis can develop for the first time in old age. This is called ‘late onset psychosis’ above the age of 40 and ‘very late onset’ above the age of 60 (paraphrenia.)
- Positive symptoms are more common than negative symptoms and occur ore commonly in women (lose protective factor of oestrogen.)
Definition of dementia, when can it be diagnosed
An acquired progressive degenerative disorder giving global impairment of all mental functions in clear consciousness (must be present in clear consciousness for 6 months.)
Definition of mirror sign and sun downing
- Mirror sign = autoprosopagnosia, inability to recognise own reflection.
- Sun-downing = confusion worsening as in the evening
What is the prevalence of dementia in over 65 and over 80 year olds
5% over 65 and 20% over 80
Describe the geenral presentation of dementia
Problems are often attributed to ‘normal ageing’ or absent-mindedness at first
- Dementia often begins with forgetfulness of recent events (anterograde amnesia.) This may first present with uncharacteristic mistakes (muddling up appointments.) With time, this then progresses to loss of long-term memory (retrograde amnesia.) Disorientated to time then place then person.
- Problems with speech and language include both receptive and expressive aphasia.
- May also get subcortical and behavioural symptoms
- Behavioural and psychological symptoms of dementia: Behavioural= restlessness, disturbed sleep/day-night reversal, shouting, screaming, swearing sexual disinhibition, aggression. Psychological= delusions, hallucinations, depression/ anxiety
Prevalence of Alzheimer’s dementia. What are the RFs for AD
- Most common form of dementia- 50-70% of dementia in older people
- Risk factors: Down’s syndrome, previous head injury, hypothyroidism, family Hx, female sex, low IQ, vascular risk factors
What predisposes AD genetically? Why are patients with Down’s Syndrome more at risk
- 40% have a positive family history of AD. Heritability (70%) is even greater if there is a history of early onset dementia (<55 y/o).
- Inheritance is autosomal dominant and involves mutation of chromosome 21 (Gene APP (Amyloid precursor protein) and chromosome 19 (Apolipoprotein E- involved in breaking down β-Amyloid.)
- People with Down’s syndrome are at greater risk of alzheimer’s due to having three copies of the APP gene on chr21
Describe the common neuropathology of AD
- Amyloid plaques (beta amyloid deposits which can form beta pleated sheets in the hippocampus, amygdala) disrupt signalling between neurones, trigger immune-mediated inflammation and damage blood vessels to cause haemorrhage
- Neurofibrillary tangles form after plaques trigger abnormal tau phosphorylation.
- This accompanies atrophy, first in the hippocampus, then in the temporal and parietal lobes. Plaques and tangles lead to a loss of cholinergic neuronal function.
What is the cholinergic hypothesis of AD
- Pathological changes lead to degeneration of cholinergic nuclei in the basal forebrain- nucleus basalis leading to a decrease in Ach.
What is the presentation of AD
Slow progressive decline in memory with a late pattern of onset. Poor spatial navigation can be an early sign. Usually get short term memory loss followed by long term memory loss. Causes a decline in judgement, thinking, planning and organising. Are aware of the environment and consciousness is preserved.
What are the FOUR As of AD
_A_mnesia, _A_phasia, _A_gnosia, _A_praxia
What can be seen on MRI or CT in AD
- Hippocampal atrophy (medial temporal lobe atrophy). In end-stage there is widespread atrophy, which is no different from other end-stage dementias. Therefore, in imaging we have to identify AD in earlier stages and concentrate on the hippocampus and medial temporal lobe.
Prevalence and causes of vascular dementia
- 2nd most common cause of dementia after AD
- Results from small strokes, caused by thromboemboli or arteriosclerosis (stroke-related dementia.) On imaging, arteriosclerosis, cortical ischaemia and infarcts predominate (multiple lucenscies)
