Dementia Flashcards
Definition of dementia
Disorder of memory function and cognitive impairment that intereferes with daily function and independence
Areas of impairment
Memory, orientation, visuospatial perception, language, higher executive functions (planning, organizing, sequencing)
Dementia vs Delirium
Delirium - refers to a disturbance of consciousness, reduced awareness, attention and disorganized thinking is common, waxing and waning LOC, develops over a short time (hrs to days), reversible cause of cognitive dysfunction, typically due to a general medical condition
Dementia - Implies a stable, sustained consciousness, progressive (not reversible) course, develops over months to years, implies neurodegenerative disorder
Dementia vs depression
It is sometimes difficult to distinguish the two, especially in the elderly; sometimes you can treat the depression and see if the dementia improves
Mild Cognitive Impairment
MCI implies that there is : subjective decline in memory, Preserved daily functioning (uninhibitied), does not meet dementia criteria
Subtypes of MCI - amnestic MCI -> memory only dysfunction, multiple domain MCI -> memory + cognitive problems, single nonmemory domain MCI -> non-memory dysfunction
There is an increased risk to developing dementia (especially AD) later in life
Who gets dementia?
Most commonly the elder (5% of people 65-70; 45% of people over 85)
Hereditary forms of dementia can occur in younger people
Women = Men
Dementia changes may start early in life (HTN and other vascular risk factors may predispose all patients to dementia)
Causes of dementia
Alzheimer’s disease -> 50-80% (most common)
Vascular
Lewy Body dementia 20%
Mixed Alzheimer’s 10%
Depression
Metabolic, drugs, infections, structural lesions
Pick’s dease, FTD, huntington’s
Reversible causes of dementia
Thyroid function, ESR, CBC, electrolytes, renal function, LFTs, ammonia, Infectious studies (HIV, RPR, Tb), Heavy metal screen (PB, HG, Arsenic)
Alzheimer’s Disease
General - Most common form of dementia
APO e4 alleles (homozygous increases the risk)
Neuropathology - final formal dx is made only at autopsy, brain atrophy, Neuritic plaques and Neurofibrillary tangles (CA1 layer of hippocampus, subiculum)
Neuroradiology - MRI/CT (atrophy) SPECT (hypoperfusion)
Dementia with Lewy Bodies
Cognitive problems (develop early or first) - variability and fluctuations of cognitive problems -> memory, executive dysfunction, verbal blocking, spatial or geographic disorientation, visuospatial impairment, misidentification of people, visual hallucinations, illusions, delusions, agitation, anxiety Motor dysfunction (Parkinsonism) Autonomic dysfunction (orthostatic hypotension) Sleep disorders (primarily REM sleep disorders) Lewy body pathology (cortex, subcortical, spinal cord) -> round, intractyoplasmic inclusions
Normal pressure hydrocephalus
Triad (course is usually weeks to months) - gait apraxia (magnetic gait - usually first manifestation), urinary incontinence, dementia
Imaging - CT shows large ventricles (out of proportion to sulci), radioisotope diffusion study (CSF flow study)
LP - normal or low opening pressure ( Miller Fisher Test (but dementia may not improve right after tap
Treatment -> VP shunt
Vascular dementia (multi-infarct dementia)
Can occur in conjunction with AD or other dementias, no uniform diagnostic criteria (Clues to dx: history of previous strokes or TIAs, cognitive deficits associated with strokes, evidence of infarcts, stepwise cognitive decline (sometimes with long plateus)
Series of small strokes leading a decline in intellectual function
Incidence of post stroke dementia -> 6-32% at 3 months
Risk factors for vascular dementia (same as stroke) - age, sex (M>F), HTN, HLP, Hyperhomocysteinemia, increase Lipoprotein a, poorly controlled DM, embolic source (afib, cardiac valves), hypercoagulabe disorders, genetic factors (moya moya, mt disorders)
Treatment - rapid assesment and treatment with strokes (IV or intra-arterial tPA, anticoagulation when indicated, BP, BG management, good secondary stroke prevention therapy
Frontotemporal Dementia
Group of neurodegenerative dementia disorders in which the frontal and temporal lobes are involved
patients usually show personality changes first with speech, memory and cognition decline over time
no effective tx for these disorders
modified neary criteria for FTD classification
Types of FTDs: Picks disease, progressive nonfluent aphasia, FTD with motor neuron disease, FTD with parkinsonism, Semantic dementia, progressive apraxia
Pick’s disease
Frontal and temporal lobe atrophy seen on autopsy with pick bodies seen (tau proteins) in cortex
Clinical findings -> impulsivity, poor judgement, poor organizational skills, neglect of social and personal responsibilites (cleanliness) - also have syn-nuclein, ubiquitin DO NOT HAVE 14-3-3 (CJD protein)
Frontotemporal atrophy seen on MRI as disease progresses
Usually starts in 40s to 60s
No treatment is available
Dementia treatment
If reversible, treat the underlying cause (hypothyroidism)
Disease modifying agents (no cure) - Tacrine (Cognex) rarely used due to liver issues, Cholinesterase inhibitors -> Donepazil (Aricept), Rivastgimine (Exelon), Galantamine (Remnyl) increase ACh seems to slow down progression and preserve memory
Memantine (Namenda) - Anti-glutame med, lots of side effects, expensive minimal beneficts, used in addition to cholinesterase inhibitors
Symptomatic treatments - Depression SSRIs
Movement disorders -> usually parkinsonism
Psychosis/Sun-downing -> newer atypical antipsychotics have fewer side effects
Care issues - supervision and safety at home, finanical issues, progressively increasing care and monitoring, likely will eventually require nursing home care, may require hospic/palliative care
