DEMENTIA Q What other types of dementia are

DEMENTIA • Q: What other types of dementia are there? • Q: Do they have the same pathophysiology as Alzeimer dementia?

DEMENTIA Dementia is a syndrome due to disease of the brain, usually of a chronic or progressive nature in which there is disturbance of multiple cortical functions, calculations, learning capacity, language and judgement. Consciousness is not clouded. Impaired cognitive function are commonly accompanied by and occasionally preceded by deterioration in emotional control, social behavior and motivation. (World Health Organization, as cited in Mc. Cance & Huether, 2006)

DEMENTIA Classification is based on Etiologic factors: Location: • Trauma • Tumours • Vascular Disorders • Infections • Cortical • Subcortical • Combined Cortical/Subcortical (Mc. Cance & Huether, 2006)

Cortical Dementias v. Alzheimer Disease v. Pick Disease (Cummings & Benson, 1992, as cited in Mc. Cance & Heuther, 2006)

Subcortical Dementias v. Extrapyramidal Syndromes: • Parkinson Disease, Huntington Disease, Progressive supranuclear palsy, Wilson Disease, Spinocerebellar degeneration, idiopathic basal ganglia calcification v. Hydrocephalus v. Dementia Syndromes of Depression (Cummings & Benson, 1992, as cited in Mc. Cance & Heuther, 2006)

Subcortical Dementias v Toxic and Metabolic encephalopathies: • Systemic illness, endocrinopathies, deficiency states, drug intoxication, heavy metal exposure, industrial dementias (Cummings & Benson, 1992, as cited in Mc. Cance & Heuther, 2006)

Combined Cortical/Subcortical Dementias v Multiinfarct dementia v. Infectious dementia • AIDS, , Kuru (Cummings & Benson, 1992, as cited in Mc. Cance & Heuther, 2006)

DEMENTIA • Q: What other types of dementia are there? A: NUMEROUS! • Q: Do they have the same pathophysiology as Alzeimer dementia?

Compare & Contrast: Pathophysiology of Dementia • Alzheimer Disease • Vascular Dementia • Frontotemporal Lobe Dementia • Creutzfeldt-Jakob Disease • Parkinson Disease • Dementia with Lewy Bodies

Alzheimer Disease • Formation of neurofibrillary tangles d/t the chemical changes in tau (cause unknown) • Normally, tau stabilizes microtubules of the healthy neuron • Threads of tau clump together and tangle • Result: Microtubules disintegrate = breakdown of transportation and communication with other neurons, leading to neuron death (Linton & Lach, 2006)

Alzheimer Disease • Beta amyloid plaques form when amyloid precursor protein (APP – important for neuron survival) becomes fragmented and clumps together in diffuse plaques (cause unknown) (Linton & Lach, 2006)

Vascular Dementia • Disruption of neural systems responsible for cognition d/t ischemia, hemorrhagic brain lesions and hypoperfusion • Hemorrhage or ischemia result in necrosis or cavitation (the formation of cavities) of brain tissue • Also evidence of atherosclerotic disease • Risk factors include: HTH, DM, cardiac abnormalities, hyperlipidemia, smoking (Linton & Lach, 2006)

Frontotemporal Lobe Dementia 1. 2. 3. 3 Pathological Presentations Abnormal accumulations of tau proteins in neurons and glial cells Tau negative but ubiquitin protein positive inclusions in areas of the brain Presences of frontotemporal lobe dementia with no distinctive pathology (Linton & Lach, 2006)

Creutzfeld-Jacob Disease • Conversion of normal prion proteins in the brain into abnormally shaped protease-resistant prion proteins • Results in neuronal dysfunction and neuronal death (Linton & Lach, 2006)

Parkinson Disease • Degeneration of basal ganglia and extrapyramidal nervous system • Loss of dopaminergic neurons in substantia nigra causes a series of circuitry changes in the basal ganglia that lead to motor disturbances (Linton & Lach, 2006)

Dementia with Lewy Bodies • Occurring in the cerebral cortex, a Lewy body is a inclusion in a neuron composed of the protein alpha- synuclein (Linton & Lach, 2006)

DEMENTIA • Q: What other types of dementia are there? A: NUMEROUS! • Q: Do they have the same pathophysiology as Alzeimer dementia? A: No. Multiple etiological factors result in multiple pathophysiological processes. Yet, relationships between various assaults to the brain do exist. (Linton & Lach, 2006)

DEMENTIA For example: • Alzheimer disease often co-exists with vascular dementia or Parkinson disease Also – a common themes: Problematic proteins! • Abnormal protein deposits/accumulations/clumps • Protein resistance and chemical changes • Change in shape/fragmentation (NIH/National Institute on Aging, 2007)

REFERENCES Linton, Adrienne Dill. Matteson’s & Mc. Connell’s Gerontological Concepts and Practice, 3 rd Edition. Saunders Book Company. NIH/National Institute on Aging (2007, June 14). Mix Of Disease Processes Found In Brains of Most People With Dementia. Science. Daily. Retrieved January 28 th 2009 from http: //www. sciencedaily. com/releases/2007/06/070613163300. htm Mc. Cance, K. L. , & Huether, S. E. (2006). Pathophysiology: The biological basis for disease in adults and children (5 th ed. ). St. Louis, MI: Elsevir Mosby