Cognitive and Dementia Epidemiology Flashcards
What are the characteristics of mild cognitive impairment?
Before dementia
Awareness of cognitive decline
Preserved everyday function
Amnestic/non-amnestic
What are the predictors of MCI progression to AD?
Degree of cognitive impairment at MCI classification
APOE ε4 allele
Neuroimaging markers - hippocampal atrophy, amyloid, temporal and parietal hypometabolism
Increased CSF AB and tau
Nutrition and metabolism - diabetes, low folate
Psychiatric symptoms - e.g. depression
What is the main neuropathological change in MCI?
Enlarged sulci and ventricles
What does the cognitive impairment used to diagnose dementia include?
Impaired memory
Impaired reasoning and complex task-handling
Impaired recognition
Behavioural and personality changes
Name 5 causes of delirium
Infection Trauma CNS pathology Deficiencies Hospitalisaton
Name 5 rare causes of dementia
Metabolic - folate deficiency Inflammation/infection - e.g. autoimmune diseases Degenerative disease - e.g. HD Alcohol Brain tumours
What are the diagnostic investigations conducted for dementia?
Blood tests - exclude some reversible causes
Profile cognitive domains - see change
Brain imaging - exclude brain tumour
EEG - exclude seizures
What are the symptoms of AD?
Prominent deficits in episodic memory, language, recognition, executive function
Parietal lobe functions affected early
Global cognitive deficits
Preserved personality
What are the key diagnostic investigations for AD?
MRI - hippocampal atrophy - then global cerebral atrophy
EEG - loss of alpha rhythm
Neuropsychology - impaired episodic memory and other cognitive domains
What is the pathology of AD?
Neurofibrillary tau tangles
AB plaques
ACh deficiency
How is AD treated?
Non-pharmacological
ChE inhibitors
Memantine - NMDAR blocker
What is the cause of vascular cognitive impairment (VCI)?
Small vessel disease
Some large vessel strokes
What are the symptoms of vascular cognitive impairment (VCI)?
Depend on brain area of stroke
What are the key diagnostic investigations for VCI?
Imaging - for infarcts, small vessel disease
EEG - excess slow activity
Neuropsychology - impaired executive function
What is the progression pattern of VCI?
Step-like
What are the symptoms of dementia with Lewy bodies?
Executive function, parietal lobe, visual deficits
Visual hallucinations
Parkinsonian motor features
REM sleep disorder
Neuroleptic sensitivity - as neuroleptics decrease DA - worsen Parkinsonian symptoms
What are the treatments for VCI?
Non-pharmacological
ChE inhibitors
Name the 3 types of FTD and their main symptom
Behavioural variant FTD - inappropriate behaviour
Semantic dementia - inability to understand language
Progressive non-fluent aphasia - speech difficulty
Which genes are implicated in FTD?
MAPT
GRN
C9orf72
What is the main pathology in FTD?
Frontal and temporal lobe atrophy
What is ACE-III?
Mental state test - attention, verbal fluency, memory, language, visuospatial function
How does APOE ε4 affect ACE-III at 69yrs old?
Small negative effect
In the NSHD what is the effect of homozygous APOE ε4?
Highest verbal memory impairment risk
How does childhood cognition affect ACE-III at 69yrs old?
Via midlife reading ability
Independently
Which factors are considered by an elaborated life-course framework for cognitive ageing?
Early life Childhood cognition Education Midlife factors Cognitive ageing
Which factors do early life events independently affect?
Childhood cognition
Education
Midlife factors
Name the key early life events
Foetal and infant skeletal and neural growth Nutrition Obstretic insult Positive nurturing Parental involvement Early adversity
What is the importance of foetal and infant skeletal and neural growth?
Linked to cognitive development - endocrine processes driving skeletal growth in utero also drive brain development
What is the importance of early life nutrition?
Breast milk n-3 PUFAs directly increase offspring IQ
Infant diet high in fruit and vegetables linked to higher IQ
What is the importance of obstretic insult and what are the limitations of this?
Alcohol and drug use during pregnancy linked to offspring behavioural and cognitive problems
Could be confounded by maternal genetics selecting these behaviours
Difficult to tell which behaviours due to prenatal exposure - which due to postnatal learning - as continuity in exposure
What is the importance of parental involvement?
Higher parental interest in education correlates with higher offspring reading scores
What is the importance of early adversity?
Poor material home conditions in childhood linked to decreased visual search speed in adulthood
Which factors does childhood cognition independently affect?
Education
Cognitive ageing
What is the strongest single factor affecting cognitive ageing?
Childhood cognition
What was the grammatical complexity of autobiographies written by nuns a strong predictor of?
Later life cognitive function and AD risk
Which type of dementia is childhood IQ associated with?
Vascular dementia
Which factors does education independently affect?
Midlife factors
Cognitive ageing
What is the link between childhood cognition, education, and adult cognition?
Childhood cognition independently affects education
Education independently affects adult cognition
Name the key midlife factors
Physical activity
Tobacco use
How does physical activity affect AD risk?
Decreases
How is the rate of verbal memory decline altered in those who exercise in midlife?
Slower
What are the possible mechanisms behind the effect of physical activity on cognitive decline?
Exercise promotes hippocampal neurogenesis
Increased capillary density in cerebellum - linked to frontal cortex
Decreases cardiovascular disease - prevents cerebrovascular disease
How does smoking affect dementia risk?
Increases
In the NSHD which measure of cognition was worse in heavy smokers than light smokers?
Verbal memory decline
What are the possible mechanisms behind the effect of tobacco use on cognitive decline?
Oxidative stress
Inflammation
Atherosclerosis
White matter damage
