Dementia Definition Dementia is a syndrome manifested by
Dementia
Definition Dementia is a syndrome manifested by several cognitive deficits that include memory impairment involving at least one of the following: aphasia(language disturbance), agnosia(inability to carry out motor activities despite intact motor function), apraxia(failure to recognize or identify objects despite intact sensory function) that interferes with social, occupational, or interpersonal
Additional features Emotional lability Impairment of intellect Mood, personality, judgment, and social behavior -Thought abnormalities Urinary and fecal incontenence Disorientation Neurological signs +/-
D= Drugs, Delirium E=Emotions (such as depression) and Endocrine Disorders M=Metabolic Disturbances E=Eye and Ear Impairments N=Nutritional Disorders T=Tumors, Toxicity, Trauma to Head I= Infectious Disorders A=Alcohol, Arteriosclerosis
Possible Etiologies of Dementia Degenerative dementias Alzheimer's disease Frontotemporal dementias (e. g. , Pick's disease) Parkinson's disease Lewy body dementia Idiopathic cerebral ferrocalcinosis (Fahr's disease) Miscellaneous Huntington's disease Wilson's disease Psychiatric Pseudodementia of depression Cognitive decline in late-life schizophrenia Physiologic Normal pressure hydrocephalus Metabolic Vitamin deficiencies (e. g. , vitamin B 12, folate) Endocrinopathies (e. g. , hypothyroidism) Chronic metabolic disturbances (e. g. , uremia)
Contd… Tumor Primary or metastatic (e. g. , meningioma or metastatic breast or lung cancer) Traumatic Dementia pugilistica, posttraumatic dementia Subdural hematoma Infection Prion diseases (e. g. , Creutzfeldt-Jakob disease Acquired immune deficiency syndrome (AIDS) Syphilis Cardiac, vascular, and anoxia Infarction (single or multiple) Binswanger's disease (subcortical arteriosclerotic encephalopathy) Hemodynamic insufficiency (e. g. , hypoperfusion or hypoxia) Demyelinating diseases Multiple sclerosis Drugs and toxins Alcohol Irradiation Pseudodementia due to medications (e. g. , anticholinergics) Carbon monoxide
DIAGNOSIS According to the ICD-10 the following features are required for the diagnosis: 1)evidence of decline in both memory and thinking, sufficient enough to impair personal activities of daily living. 2)Memory impairment typically affects the registration, storage and retrieval of new information(recent memory)but previously learned material(remote memory) may also be lost, particularly in later stages.
3)Thinking is impaired, the flow of ideas is reduced, and the reasoning capacity is also impaired. 4)Presence of clear consciousness. (Consciousness can be impaired if delirium is also present). 5) Duration of atleast 6 months.
Features Cortical dementia Subcortical dementia 1. Site of lesion Cortex(Frontal and temporo-parieto-occipital association areas and hippocampus) Subcortical grey matter (thalamus, basal ganglia, brain stem) 2. Examples Alzheimer’s disease Pick’s disease Huntington’ chorea Parkinson’s disease 3. Severity Severe Mild to moderate ` 4. Motor system Usually normal FlexedExtended psture, Tremors, chorea 5. Other features , depression uncommon. Severe aphasia, amnesia, agnosia, Delusions, depression rarely mania
Types of Dementia findings Alzheimer’ Associated pathological Generalised atrophy of the brain. Widening of the sulci and ventricles. Extracellular senile plaques and intracellular neurofibrillary tangles. Reduced levels of neurotransmitters, Multiple white matter infarcts. Cystic necrosis of infarcted areas, reactive gliosis, patches of demyelisation of white matter. Lewy bodies (eosinophilic intracellular structures) in cortical and subcortical neurones. s disease Vascular dementia Lewy body dementia
Dementia of the Alzheimer's Type AD is a neurodegenerative disease of the brain with an average duration of 8– 10 years between onset and death, AD has an insidious onset, most commonly after the age of 60 years, AD is divided into three stages based on functional and cognitive capacity : Early AD MMSE is equal to or greater than 18, moderate AD MMSE is between 12 and 18, and severe AD MMSE is less than 12. On average the MMSE score declines by 3 points per year. Short-term memory loss is the earliest manifestation , with mild aphasia and impaired visuospatial ability, which evolve into fluent aphasia and constructional apraxia. Other cognitive functions such as calculations, reasoning, judgment, and executive functioning also become impaired. Donepezil, rivastigmine, galantamine, memantine are the drugs presently approved by the Food and Drug Administration (FDA) for treatment of AD
Compare central sulcus of Alzheimer’s patient with normal 81 year old woman
Normal vs AD Brain Normal brain Alzheimer’s brain
Vascular Dementia Vascular dementia accounts for approximately 15% of all dementias. Vascular dementia was classically characterized by an abrupt onset and stepwise deterioration of dementia and have risk factors such as hypertension, cardiac disease, diabetes, and strokes.
Alcohol-Related Dementia Chronic alcohol use has long been considered an etiology of dementia. Wernicke's encephalopathy, and Korsakoff's syndrome may be the de facto etiology for alcohol-related dementia
Dementia due to Parkinson's Disease Parkinson's disease (PD)-induced dementia accounts for 5– 10% of all dementias. Parkinson's disease is a slowly progressive neurologic condition associated with dopamine deficiency and characterized by the triad of resting tremor, bradykinesia, and rigidity. Its onset is usually in middle to late life. Approximately 40– 50% of patients with PD develop dementia.
Dementia due to Lewy Body Disease It has a more rapid onset with a fluctuating course. Visual hallucinations, parkinsonian symptoms, and susceptibility to delirium are common early in the course. Pt are sensitive to extrapyramidal side effects of antipsychotic medications. Histopathologic feature of LBD is the presence of Lewy inclusion bodies in the cerebral cortex.
Frontal Lobe Dementias Pick's disease and other forms of frontotemporal dementia have impaired executive functioning and personality and behavioral changes, including disinhibition, affective blunting, and deterioration of social skills. In Pick's disease, there is profound atrophy of the frontal and/or temporal lobes, with characteristic Pick inclusion bodies found on autopsy. It typically presents between the ages of 50 and 60 years
Difference between Dementia and Pseudodementia Dementia pseudodementia (Depre ssive) 1. Patient rarely complains of the cognitive impairment. 1. Patient usually always complaints about the impairment. 2. Patient emphasizes achievements. 2. Patient emphasizes disability. 3. Patient appears unconcerned. 3. Patient communicates distress. 4. Patient makes mistake on examination. 4. Don’t know answer are frequent. 5. Recent memory impairment found on examination. 5. Recent memory impairment rarely found on examination.
6. Consistently poor performance on similar tests. 6. Marked variability in performance on similar tests. 7. History of depression uncommon. 7. Past history of maniacdepressive episodes may be present.
Basic Investigations CBC Urinalysis Blood glucose Electrolytes RFT, TFT, Arterial PO 2/PCO 2 Chest x-ray, EEG, LP, CT/MRI, Drug level
Treatment Rx the underlying cause Supportive care Benzodiazepines (lorazepam, oxazepam) for anxiety Citolapram , sertraline for depression Antipsychotics (haloperidole, risperidone) Chlorpromazine Donepezil or rivastigmine in AD
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