Dementia

1. Dementia

2. Dementia is a progressive impairment of cognitive functions occurring in clear consciousness. • The major defect in dementia is Memory loss (antrograde or retrograde). • Other cognitive functions (Attention, Comprehension, Abstract thinking, Judgment, Mood and affect, Personality, Social behavior)

3. Diagnosis • According to DSM-IV-TR criteria: • Development of multiple cognitive impairments: • Memory (antrograde & retrograde). • One (or more) of the following: • Aphasia • Apraxia • Agnosia • Disturbance in executive functioning (planning – sequencing - organizing – abstracting).

4. Both A1 & A2 cause significant impairment in social and occupational functioning. • The deficits don’t occur in the course of delirium.

5. Epidemiology • Prevalence: • 5% in population over 65 years. • Up to 40% in population over 85 years. • 50 % - 60 % of all demented have Alzheimer's disease.

6. Causes of Dementia • Neurodegenerative Diseases • Alzheimer’s disease • Parkinson’s disease • Diffuse Lewy body disease • Huntington’s disease • Pick’s disease • Vascular Disease

7. Demyelinating Disease • Multiple sclerosis • Infections • Human immunodeficiency virus • Tertiary syphilis • Trauma • Tumors • Primary Psychiatric • Pseudodementia

8. Metabolic • Vitamin deficiencies • Chronic metabolic disturbances • Physiologic • Normal pressure hydrocephalus • Epilepsy • Drugs & Toxins • Alcohol • Medications • CO • Irradiation

9. The major dementia syndromes • Alzheimer disease • Vascular dementia • Dementia with Lewy bodies • Parkinson disease with dementia • Frontotemporal dementia (pick’s dementia) • Reversible dementias

10. Reversible DEMENTIA • D = Drugs • E = Emotions (pseudodementia)& Endocrine Disease • M = Metabolic Disturbances • E = Eye & Ear Impairments • N = Nutritional Disorders, Normal pressure hydrocephalus • T = Tumors, Toxicity, Trauma to Head • I = Infections • A = Alcohol

11. Pathophysiology • Dementia is a symptom of a variety of specific structural brain diseases as well as several system degenerations. Alzheimer's disease presently is the commonest cause in the developed world, causing a cortical & subcortical degeneration of ascending cholinergic neurons and large pyramidal cells in the cerebral cortex.

12. Alzheimer’s Disease • Alois Alzheimer (1864 – 1915)

13. Progressive dementia when all known causes have been ruled out. “ Diagnosed By exclusion “ • 2 types • With early onset (before 65 years old) • With late onset ( after 65 years old)

14. Etiology • Genetic factor • Decreased brain Ach Concentrations • Decreased brain choline acetyltransferase enzyme • Degeneration of cholinergic neurons in the nucleus basalis.

15. Neuropathology • Brain atrophy due to extensive neuronal loss seen by Brain Imaging. • Two principal changes: (histopathologicly) • senile or neuritic plaques (chemical deposits consisting of degenerating nerve cells combined with a form of protein called ß-Amyloid) • neurofibrillary tangles (malformations within nerve cells).

16. PET scan

17. Diagnosis • Criteria mentioned before + • Gradual onset and progressive course. • Exclusion of systemic diseases causing dementia. • The disturbance is not better accounted for by another Axis I disorder (e.g., major depression) • Definite diagnosis is postmortem (histopahologically)

18. Vascular Dementia • Dementia due to cerebrovascular diseases • 15 % - 30 % of all dementias. • Multiple cognitive impairments and behavioral changes + neurological signs & symptoms (gait abnormaily – weakness of an extremity -Babinski's sign) • Risk factors (hypertension, heart diseases, Diabetes mellitus, hyperlipidemia)

19. Psychiatric co-morbidities • Depression • Psychosis • Delirium • Anxiety

20. Work up • Mini mental state examination • Full physical examination (neurological) • Full assessment for co-morbidities • Neuro-imaging (Brain CT, PET) • Lab investigations (Chemistry , CBC , LFTs ,KFTs , ESR , TSH , B12 and folate)

21. Treatment • Treat medical problems • Provide orientation cues (clock , calendar) • Education and support for patient and family (day programs, support groups, home care) • Pharmacotherapy (doesn’t cure, but slow the disease process)

22. Pharmacotherapy • Cholinesterase inhibitors in Alzheimer’s disease • Rivastigmine (Exelon) 3 – 6 mg 2x/day • Tacrine (Cognex) 30 – 40 mg 4x/day • Donepezil (Aricept) 5 – 10 mg /day • SE: Nausea, vomiting, diarrhea and bradycardia in some people

23. N-Methyl-D-Aspartate (NMDA) Receptor Blocker • Memantine (Namenda®) is a unique medicine that works differently than cholinesterase inhibitors. • It may protect the brain from further damage. • It is usually used along with a cholinesterase inhibitor. Dizziness is the most common side effect, and aggression and hallucinations may worsen in some people.

24. Treatment of behavioral symptoms • Depression • antidepressant medicine SSRIs, are usually preferred (fluoxetine (Prozac® ) • Behavioral therapy involves changing the environment (e.g., encouraging exercise, socializing with others)

25. Anxiety • Anxiolytics (not benzodiazepine) as it interferes with the formation and consolidation of memories of new material and may induce complete anterograde amnesia • SleepDisturbance • Trazodone 25 to 150 mg PO qhs • Agitation Antipsychotics (haloperidol)

26. Course & Prognosis • Course • Progressive • Remitting • Stable • Prognosis • Irreversible (85 %) • Reversible (15 %)