340 likes | 356 Views
Understanding Dementia. Inside the Human Brain. To understand, Dementia it’s important to know a bit about the brain…. The Brain’s Vital Statistics Adult weight: about 1.5kg Adult size: a medium cauliflower Number of neurons: 100,000,000,000 (100 billion)
E N D
Inside the Human Brain To understand, Dementia it’s important to know a bit about the brain… • The Brain’s Vital Statistics • Adult weight: about 1.5kg • Adult size: a medium cauliflower • Number of neurons: 100,000,000,000 (100 billion) • Number of synapses (the gap between neurons): 100,000,000,000,000 (100 trillion)
Inside the Human Brain Neurons • The brain has billions of neurons, each with an axon and many dendrites. • To stay healthy, neurons must communicate with each other, carry out metabolism, and repair themselves. • AD disrupts all three of these essential jobs.
Inside the Human Brain The Brain in Action Hearing Words Speaking Words Seeing Words Thinking about Words Different mental activities take place in different parts of the brain. Positron emission tomography (PET) scans can measure this activity. Chemicals tagged with a tracer “light up” activated regions shown in red and yellow. Slide 13
Some types of Memory improveor remain unchanged with ageing Semantic Memory • May improve with age • Memory for concepts, facts, language (vocabulary) Procedural memory • Driving a car, using a phone
Some types of Memory may worsen with age Episodic memory ( where, when, what) • Forgetting where the car was parked • Forgetting items on a grocery list • Difficulty remembering appointments
Cognitive decline with aging • Mild changes in memory and rate of information processing • Not progressive • Does not interfere with daily function
Memory and ageing • 40% of people aged > 65 yrs have age associated memory impairment. 1% will progress to dementia. • 10% have mild cognitive impairment (MCI) • 15% of the MCI patients develop Alzheimer’s disease each year.
What is Dementia? • Dementiais a descriptive term for a group of symptoms caused by disorders that affect the brain. It is not a specific disease. • It is a progressive brain syndrome that affects memory, thinking, behaviour & emotion. • Dementia is NOT part of normal ageing
The 4 A’s • Amnesia: Memory loss-initially short term progression to long term (loss of recognition of familiar people, places and events) • Aphasia: Impaired comprehension or performance of communication (speech, writing) • Agnosia: Impaired ability to correctly recognise familiar objects or interpret various stimuli • Apraxia: Impairment of purposeful movements requiring skill or dexterity
Risk Factors for Dementia • Age • Family history • Lifestyle Physical exercise Mental exercise Diet Tobacco Head injury • Hypertension • Elevated serum cholesterol • Elevated serum homocysteine
Is it Dementia? Ten Warning Signs 1. Recent Memory Loss 2. Difficulty in performing familiar tasks 3. Problems with Language 4.Disorientation to time and place 5. Poor Judgment Alz.Association, 2000
Is it Dementia? Ten Warning Signs 6. Impaired Abstract Thinking 7. Misplacing Things 8. Changes in Mood and Behaviour 9. Changes in Personality 10. Loss of Initiative Alz.Association, 2000
Causes of Dementia There are more than 100 causes of dementia. Common causes are Alzheimer’s disease Vascular dementia Mixed Dementia Frontotemporal dementia Diffuse Lewy body disease Parkinson’s disease Early Onset
Types of Dementia • Alzheimer’s • Mixed ► 80% of all dementias • Lewy-body • Frontotemporal • Vascular • Other neurodegenerations (e.g.Huntingdon’s) • Infections (e.g. HIV,Jakob-Creutzfeld)
Interactions Between Vascular Dementia and Alzheimer’s Disease AD Mixed VaD 80% of all Dementias
Treatable (Reversible) causes of Dementias • Infections • Vitamin deficiency • Hypothyroidism • Medications • Depression • Tumours • Alcohol • Hydrocephalus
Healthy brain v/s Alzheimer’s brain Pet Scan of Normal Brain Pet Scan of Alzheimer’s Disease (AD) Brain Image courtesy: ADEAR (Alzheimer’s Disease Education and Referral Center, http://www.nia.nih.gov/Alzheimers/Resources)
The Epidemic is here!!! • Dementia affects 1 in 20 people over the age of 65 and 1 in 5 over the age of 80 India • 70 Million Elderly (6.9%) 2001 • 170 million (12.4%) 2026 • 3 Million AD patients • This may double in the next 20 years
Natural History of AD Severe Early diagnosis Mild-to-moderate 30 Symptoms 25 Diagnosis 20 Loss of functional independence 15 Mini-Mental State Examination (MMSE) Behavioural problems 10 Nursing home placemen t 5 Death 0 1 2 3 4 5 6 7 8 9 Time (years) Reproduced with permission from Feldman and Gracon, 1996.
Assessment of Dementia: domains • Cognitive • Functional • Behavioural • Affective
History • Onset and duration • Focal neurological symptoms • Precipitating events • Past history and risk factors • Social history and risks (fire, wandering, summoning help, low TI medications) • Medications (all of them) • Order lab tests?
Examination • Overall appearance (e.g. cleanliness, grooming, trauma, clothing) • General physical ( e.g. HF, hypoxia, thyroid, tumours) • Focal neurological signs • Gait, balance
Mental status • MMSE or equivalent • Clock drawing • Complete Cognitive Assessment • Measures of insight & judgement
Laboratory • CBC • Blood sugar • Electrolytes • TSH • B12 • Calcium
Neuroimaging • Age under 65 • Focal neurological symptoms • Focal neurological signs • Short history • Head trauma • Anticoagulants or bleeding • Malignancy that might metastasize • Atypical features i.e. not suggesting AD
Treatment of Dementia - Principles • Multimodal • Depends on stage of illness • Treat underlying cause • Modification of vascular risk factors • Goals • Maximize patient’s cognitive capacity & increase the period of independent functioning • Decrease family’s burden
Treatment of Dementia • Drugs - For cognitive impairment - For behavioural symptoms • Non Pharmacological approaches • Counseling and carer support services • No cure for AD at present but medications can slow progression of disease.
“Behavioural” Interventions • Establish routine • Day programs e.g activities, exercise, socializing • In home respite • Distraction, coaching • Behavioural observation
Prevention of DementiaTips for Healthy Lifestyle • Feed the brain - reading, writing, crosswords • Say ‘no’ to TV • Exercise regularly • Eat plenty of fruit and vegetables (spinach, beetroot, broccoli, onion, corn, brinjal, plums, red grapes, oranges) • Control of BP, DM & hyperlipidemia. • Prevent head injuries – helmet/seat belts!!! • Active social life, interests and hobbies.