An overview of dementia gives an introduction to epidemiology, causes, clinical features, investigations, diagnosis, and management of dementia. Also a short description of related topics like difference between cortical and sub cortical dementia, psuedo dementia, mild cognitive impairment and reversible causes of dementia is also included.
3. September 21 – World Alzheimer’s day
September 21st was selected as world Alzheimer’s
day as it marked the tenth anniversary of
Alzheimer's Disease International, back in 1994.
ADI is an international association based in London,
UK which is active in the field of Alzheimer’s
dementia.
An overview of dementia 3
4. Contents
1. Introduction
2. Epidemiology and global burden
3. Causes
4. Clinical features
5. Investigations
6. Treatment
7. Prognosis
8. Others
a) Cortical and sub cortical dementia
b) Dementia and delirium
c) Pseudo dementia
d) Mild cognitive impairment
An overview of dementia 4
5. Introduction
Dementia literally means ‘to depart from mind’ in Latin.
It was the German Psychiatrist Emil Kraepelin who first
used the term ‘dementia praecox’ to describe the
modern day schizophrenia.
Later, it was from 1920’s that the term dementia was
started to be used in the modern day meaning.
An overview of dementia 5
6. Introduction contd...
What is dementia ?
Dementia is syndrome due to disease of the brain,
usually chronic and progressive, in which there is
disturbance in multiple higher cortical functions,
including memory, thinking, orientation, comprehension,
calculation, language, learning ability, and judgment.
– ICD 10 by WHO
An overview of dementia 6
7. Introduction contd...
- Dementia is a syndrome
- Dementia is more than just amnesia
- Dementia is often chronic, progressive and irreversible
An overview of dementia 7
9. Causes of dementia
Generally, Alzheimer’s disease is considered the most
common cause of dementia worldwide (60%) and vascular
dementia as the second commonest (30%). Other less
common types constitute up to 10% of dementias.
However, there is marked regional variation in the
prevalence. We have convincing evidence to state that
vascular dementia is more common in our part of the
world.
Study by Shaji et al from Trichur states AD:VD = 1.6:1.5
An overview of dementia 9
10. Causes of dementia
Parenchymatous
brain disease
Alzheimer’s disease, Picks disease, Huntington disease,
Parkinson’s disease, Progressive supranuclear palsy
Vascular Multi-infarct dementia, Single infarct dementia,
Binswagners disease, Specific vascular syndromes
Infections* Creutzfeldt Jacob disease, AIDS dementia, Neurosyphilis,
Chronic meningitis , Encephalitis, Whipples disease, Lyme
disease, Sarcoidosis
Metabolic* Wilsons Disease, Hepatic encephalopathy, Uremic
encephalopathy
Endocrine* Thyroid , Parathyroid , Pituitary or Adrenal dysfunction
Deficiencies* Vitamin B1, B3, B6 or B12 deficiency
Toxic causes*
Heavy metals, CO, Alcohol, Drugs like antiepileptics,
benzodiazepines and analgesics , Dialysis dementia
(Aluminium toxicity)
Other Causes*
Chronic subdural haematoma, Normal pressure
hydrocephalus, Dementia Pugilistica aka punch drunk
syndrome, neoplasm’s and other SOL.
* Generally considered reversible causes of dementia
An overview of dementia
10
11. Clinical features
Disturbances are seen in multiple higher cortical functions
like memory, thinking, orientation, comprehension,
calculations, learning, language and judgment.
Recent memory is first impaired followed by impairment
of remote memory. Immediate memory, ie attention and
concentration is usually intact and consciousness is clear.
Symptoms specific to the cause of dementia are also
noted.
An overview of dementia 11
12. Investigations in dementia
Investigations in dementia are of two broad categories,
1. To confirm / diagnose dementia
and
2. To diagnose the cause of dementia
An overview of dementia 12
13. Investigations contd..
1.Investigations to diagnose dementia.
After we clinically suspect dementia in a patient,
scales are often used to assess memory and other
cognitive functions.
2.Investigations to diagnose the cause of dementia
Once dementia is diagnosed, we need to do a battery
of tests to identify the cause of dementia.
An overview of dementia 13
14. Investigations contd…
SCALES USED IN DEMENTIA
Cognition
Mini Mental Status Examination (MMSE),
Modified MMSE (3MMSE),
Hindi MMSE - Indian version of MMSE (English and Hindi)
Clock drawing test , Trail marking Test,
Addembrook’s cognitive examination,
Alzheimer’s disease assessment scale for cognition (ADAS Cog),
Montreal Cognitive Assessment
Global
function
Barthel index,
Bristol ADL scale
General
An overview of dementia 14
15. Investigations contd…
INVESTIGATIONS IN DEMENTIA
Blood CBC
LFT – Hepatic Encephalopathy,
RFT – Uremic Encephalopathy,
TFT – Hypothyroidism
VDRL – Neurosyphilis or GPI,
ELISA for HIV – AIDS Dementia Complex
Urine Wilsons disease
Structural imaging Diffuse Cortical Atrophy with flattened sulci and
ventricular enlargement in AD.
In research, Hippocampal atrophy is considered a
biomarker of AD.
Infarct, Chronic SDH and Other SOL may be visible.
Functional imaging SPECT or PET in atypical cases – FTD
EEG CJD shows triphasic waves
Lumbar Puncture NPH, Chronic meningitis
Genetic mapping Huntingtons chorea
An overview of dementia 15
16. Treatment
Treatment of dementia will largely depend on the
etiology.
AD is often treated with cholinesterase inhibitors like
Donapezil and NMDA antagonists like Memantine.
Ginkobilobo and NSAIDS may have a role. Insomnia
and psychotic or mood symptoms need appropriate
care.
An overview of dementia 16
17. Treatment contd...
Dementia is a chronic and devastating illness which takes
away the identity of the person. By the terminal stages,
patients often become empty shells of their former selves.
Realizing this can be fatal to them.
Following non pharmacological approaches are of great
help – Insight oriented psychotherapy, Assistance in
grieving, Maximizing any areas of intact functioning,
Activity scheduling and day structuring, Cognitive skills
training, Family psycho education, Care giver stress and
burn out management.
An overview of dementia 17
18. Prognosis
Prognosis of dementia will largely depend on the
etiology.
AD often has an insidious onset with chronic and
progressive course.
VD typically has an acute onset and step ladder pattern
of progression.
Reversible causes of dementia show a good prognosis.
An overview of dementia 18
19. Other topics related to dementia
a) Cortical and sub cortical dementia
b) Dementia and delirium
c) Pseudo dementia
d) Mild cognitive impairment
An overview of dementia 19
20. Cortical and sub cortical dementia
Dementias are often classified into two broad
categories of cortical and sub cortical based on the area
of brain affected and the resulting clinical features.
This division is not very sharp as clinical features often
overlap. As a general rule, cortical dementia exhibits
more cognitive dysfunction while sub cortical dementia
has more motor symptoms.
An overview of dementia 20
21. Cortical and sub cortical dementia contd…
CORTICAL AND SUBCORTICAL DEMENTIA
Feature Cortical dementia Sub cortical dementia
Site of brain Outer cortex Sub cortical grey matter
Examples AD, Picks HD , PD , WD , PSP , HIV D
Motor symptoms Rare Usual
Memory symptoms Common Less marked
Language Aphasia +, Dysarthria - Aphasia - , Dysarthria +
Calculation Acalculia + Acalculia -
Co ordination Preserved Impaired
Posture Upright Bowed or extended
An overview of dementia 21
22. Dementia and delirium
Delirium is an etiologically nonspecific syndrome
characterized by disturbances in consciousness,
cognition, psychomotor activity, sleep wake cycle and
emotions. It is aka acute confusional state, acute brain
syndrome, ICU psychosis etc.
Delirium has a potential to get confused with dementia,
especially if no history is available regarding the onset.
Further, they both can exist together complicating the
clinical picture.
An overview of dementia 22
23. DEMENTIA VS DELIRIUM
Feature Delirium Dementia
Onset Acute Insidious
Course Fluctuating Progressive
Duration Weeks Chronic, often life long
Attention and
concentration
Impaired Intact
Orientation Impaired Intact, Impaired in later stages
Memory Impaired immediate
and recent
Impaired recent. Remote memory
imaired in late stages
Perception Hallucinations and
illusions common
Variable
Thought Delusions common Variable
Diurnal variation (+) Sun downing (-)
Floccilation (+) (-)
An overview of dementia 23
24. Psuedo dementia
Psuedo dementia (PDEM) is a word coined by Kiloh.
PDEM often occurs in depression where patients show
some cognitive dysfunction and has the potential to be
mistaken for dementia. Differentiating dementia and
psuedo dementia is important in clinical practice.
An overview of dementia 24
25. DEMENTIA VS PSUEDODEMENTIA
Dementia Psuedo dementia
History
Onset not clear Onset is somewhat
clear
Slower progression Rapid progression of
symptoms
Pt may even refuse
medical help
Pt wanting medical
help
Past psychiatric
dysfunction rare
Past h/o depression
common
Clinical features
Pt highlights
achievements
Pt highlights failures
Pt struggle to perform Little effort to perform
Pt may appear
unconcerned
Pt appears deeply
concerned
Confabulation present Absent
An overview of dementia 25
26. MCI
Mild cognitive impairment (MCI) MCI primarily identifies
a person with deteriorating cognitive impairment, but
not severe enough to be diagnosed as dementia.
European Consortium Task Force guidelines for MCI
includes,
1) Complaints about cognitive impairment,
2) Cognitive impairment on clinical examination,
3) Cognitive impairment not severe to interfere with ADL,
4) No dementia.
Management of MCI may include COX II inhibitors,
Tocopherol and antioxidants. MCI conversion to
Dementia of 2 – 30% per year is reported by Lishman.
An overview of dementia 26
1.Dementia is a syndrome. A syndrome is a set of signs and symptoms that are correlated with each other and, often with a specific disease. Dementia can occur in various disorders including Alzheimer’s disease (AD).
2.Dementia is more than just amnesia. Various higher cortical functions like MTOC2L2J are impaired. Amnesia results from injury to focal or discrete structures of brain, (like MTL structures like mamillary bodies), while dementia often results from global or diffuse brain involvement.
3. Dementia is often a chronic, progressive and irreversible condition. However, there are some important reversible causes of dementia, which will be described towards the end of this presentation.
With the advances in medical field, the life expectancy has shown a steady increase over the past decades. And the increased life expectancy has resulted in the increase of single most risk factor for dementia, the old age.
However global variation is reported in the distribution of dementia. Many reports suggest that VD is more common in India. Studies by Shaji et al from Trichur reported AD : VD = 1.6 : 1.5 in south India. In fact we have very few community based prevalence studies on dementia.
There is no perfect way in classifying the causes of dementia, and authors vary in their opinions. This is an outline of various causes of dementia.