1. Disorders of cognition An overview

2. Cognitive:  Pertaining to cognition, the process of knowing and, more precisely, the process of being aware, (knowing, thinking, learning and judging.)  Cognitive" comes from the Latin root "cognoscere" meaning to become acquainted with. Cognoscere is made up of "co-" + "gnoscere" = to come to know. Another term for cognitive is epistemic.

3. Cognitive Disorders:  Affect brain’s ability to function.  “Hardware” problem.  Involves physical changes.

4. What are cognitive disorders? Disorders in which the central feature is the impairment of-  memory,  attention,  perception and  thinking.

5. Definitions  Perception is an awareness or understanding of sensory information- Interpretation of stimuli  Attention is the cognitive process of selectively concentrating on one aspect of the environment while ignoring others -perceptual focusing  Sustained attention is concentration

6. Definitions  Memory is a mental ability to store, retain and recall information.  Thinking involves mental manipulation to form concepts,engage in problem solving and reasoning and make decisions

7. Memory  Process involved in the acquisition of information, its storage in the brain and its subsequent retrieval and use  Process by which facts are remembered

8. Immediate memory  Information is held for less than a few seconds  Visual and auditory storages are separate  Close to attention and generally not affected by memory disorders

9. Recent memory  Information is held for few days  Immediate and recent memory are together called short term memory

10. Long term memory  Capacity is large  Information is stored in a coded form

11. Stages of memory- 5 R’s  Registration-capacity to add new materials to the store  Retention-Ability to store knowledge  Retrieval –to obtain stored material from the memory  Recall- return of information in a chosen moment  Recognition is the sense of familiarity

12. Stages of memory processing

13. Case history  A middle aged man in his 40s was brought to the emergency room by his relative. He appeared disoriented and drifted in and out of consciousness. When he was conscious he appeared agitated. Patient’s examination revealed a recent bruise on the patient’s head and a blood pressure of 170/98 mm of Hg

14. Delirium  An acute organic brain syndrome characterized by clouding of consciousness and disorientation, develops over a brief period and remits quickly once the offending cause is removed.

15. Epidemiology  5-15% of all patients in medical and surgical wards  Higher in post operative patients  30% in intensive care units  40-50% recovering from hip surgery  Highest rate in post cardiotomy patients

16. . Assessment  Mental Status Exam: brief interview used to assess cognitive disorders  5 major components: 1.Appearance and behavior 2.Mood and affect 3.Thought 4.Perception 5.Sensorium and Intellect

17. Delirium 1.Features Key feature is disturbed consciousness Associated features include:  Clouded sensorium – no clear awareness of surroundings  Problems with attention  Disturbance in memory  Incoherent speech  Perceptual disturbances (e.g., hallucinations)

18. Delirium: Risk Factors  Age over 70  Depression  Dementia  Stroke, epilepsy  Alcohol abuse  Alcohol withdrawal  Psychoactive substances  Renal failure  Liver failure  Congestive heart failure  Septic shock  Malnutrition  Visual/hearing impairment  Hypothermia or fever

19. Causes of delirium  Drugs: intoxication, withdrawal, poison  Medications  Infection  Head injury  Various kinds of brain trauma (e.g., stroke) Causes

20. Course of delirium  Acute onset (within hours or days)  Transient course (days to a few weeks) (No life-long delirium)  Can be superimposed on another disorder  (e.g., dementia)

21. Treatment of delirium  Attending to precipitating problem  Treating the underlying medical condition  Prevention is most successful  Recognizing people at risk and paying special attention to those cases to avoid delirium

22. Environmental and supportive measures in delirium Education of all who interact with the patient (doctors, nurses, family, etc.). Reality orientation techniques. Firm clear communication preferably by the same staff member Use of clocks and calendars. Create an environment that optimises stimulation (e.g. adequate lighting) Reduce unnecessary noise

23. Supportive measures Mobilise patient whenever possible. Correct sensory impairments (e.g. hearing aids; glasses). Optimise patient's condition, attention to hydration, nutrition, elimination, pain control. Make environment safe (remove objects with which patient could harm self or others).

24. Sedation in delirium Use single medication. Start at low dose and titrate to effects. Give dose and reassess in 2 to 4 hours before prescribing regular dose Review dose regularly and taper and stop Consider: Haloperidol 1mg up to max of 4mg daily Lorazepam 0.5mg-1mg up to max of 4mg daily Risperidone 1mg- 4mg up to max of 6mg daily

25. Case history  A 74 year old woman who was diagnosed with breast cancer 5 years ago and treated with a simple mastectomy and chemotherapy. She has been doing well with no evidence of recurrence. During the last 5 months her husband reports that she has been having increased difficulty remembering the little details of everyday life. She frequently forgets her keys and other objects around the house, repeatedly asking directions to familiar places and has difficulty planning activities. But she denies any memory problems.

26. . Dementia 1.Features There is gradual impairment of multiple cognitive abilities including memory, language, and judgment Impairment in social/occupational functioning Ability to solve novel problems goes first followed by learned abilities (e.g., vocabulary) First signs: personality change and memory loss

27. . Dementia (cont.) Incidence is highest in older adults, but can onset at almost any age Not accurate to give one prevalence rate, because it differs by age group:  65-74:1.29%  75-84:3.83%  85+:10.14%

28. Epidemiology  Incidence is the same for males and females  Onset varies by type of dementia  e.g., Alzheimer’s vs. vascular dementia  People over age 75 at increased risk for dementia

29. Types of dementia Parenchymatous brain disease Alzheimers disease Vascular dementia Multiinfarct dementia Toxic, Alcohol Metabolic Uraemia,dialysis dementia

30. Types of dementia  Endocrine Thyroid dysfunction  Deficiency dementias Anaemia, pellagra  Infections AIDS, SSPE  Neoplasms  Trauma and hydrocephalus

31. . Dementia (cont.) Causes of dementia Direct cause linked to type of dementia  Plaques and tangles  Alzheimer’s  Blocked artery  vascular dementia Genetic factors linked to some dementias  Multiple genes  Alzheimer’s risk  Single dominant gene  Huntington’s disease Head trauma is a risk factor (e.g., boxer’s dementia )

32. . Causes (cont.)  Vascular dementia can be influenced by diet as well as genetic factors (link to heart disease)  Psychosocial factors  Higher education level is associated with lower dementia risk  Social resources and family support can improve life for patients with dementia

33. Assessment  Mental state examination done with mini mental state examination  Physical examination  EEG to rule out delirium  CT Scan cortical atrophy esp over parietal and temporal lobes

34. Investigations  MRI optional  PET reduction in glucose metabolism in temporal and posterior parietal lobes

35. Treatment  Treatment of reversible causes  Educate family about disease, financial decisions, support groups, community organizations.  Treatment of medical complications  Supportive care for the patient and the family

36. Treatment  Acetylcholine esterase inhibitors Donopezil Rivastigmine Galantamine  NMDA Receptor antagonist- Memantine

37. Other treatment strategies  Vit E  Non steroidal anti inflammatory drugs  Cholesterol lowering drugs  Amyloid beta peptide vaccination

38. Psychological treatments Memory wallet Memory skills training Teach to use navigational cues to avoid getting lost

39. Alzheimer’s disease Alzheimer’s Disease  Development of multiple cognitive deficits manifested by both: 1)Memory impairment 2)One (or more) of the following: a)Aphasia b)Apraxia c)Agnosia d)Disturbance in executive functioning

40. Alzheimer’s (cont.)  Onset usually in 60’s or 70’s Early signs in 40’s and 50’s (presenile dementia)  Definitive diagnosis can only be made on autopsy where histopathology confirmed: 1.Gross atrophy of the brain 2.Neurofibrillary tangles 3.Senile plaques

41. Multi infarct dementia  Multiple cerebral infarcts  Stepwise clinical deterioration  Fluctuating course  Presence of hypertension  O/E focal neurological signs

42. Amnestic disorders  Memory impairment  Anterograde and retrograde amnesia  Caused by general medical condition or substance use

43. Wernicke’s encephalopathy  Related to alcohol use  Related to thiamin deficiency  Pathological lesions in mamillary bodies and thalamic nuclei

44. Korsakoff’s psychosis  Short term memory distubance  Confabulation  Associated with atrophy of mamillary bodies

45. Vascular disease  Involvement of hipocampus  Parieto occipital region,bilateral medio dorsal thalamic nuclei  Basal forebrain nuclei

46. Head injury  Involvement of ant temporal poles  Post traumatic amnesia is usually one of anterograde amnesia than retrograde amnesia

47. Other causes  HIV encephalitis : medial temporal lobe involvement and short term memory deficit  Hypoxic brain damage  Alcohol blackouts  Electro convulsive therapy

48. Others  Space occupying lesion  Hypoglycaemia

49. Summary  Cognitive disorders involve an impairment of memory, attention, perception, and thinking that represents a change from previous functioning  Delirium – short-lived; treat precipitating factor (e.g., substance withdrawal) or prevent  Dementia – gradual, continual decline (e.g., Alzheimer’s)  Amnestic disorders predominantly involve memory

50. Thank you