Nervous Disorders

DEMENTIA AND ALZHEIMER'S DISEASE

Dementia is a disease that impairs the ability of the brain to remember, think or make decisions that interfere with daily routine activities. There are four types of dementia –

1) Alzheimer's Disease
2) Lewy Body Dementia
3) Vascular Dementia
4) Fronto-Temporal Dementia

Alzheimer's Disease is the most common type of dementia, begins in mid-adult life and progression occurs rapidly due to extreme loss of neurons. The pathophysiology of Alzheimer's disease has been hypothesized and documented to be the dysfunction of synaptic mechanisms with loss of functional neuronal pools. The features of Alzheimer's disease are progressive deficits in memory and other aspects of cognition. Patients with Alzheimer's disease require continuous care within a few years after the disease begins. The DSM-IV-TR (American Psychiatric Association 2000) has laid down criteria for diagnosis of Alzheimer's disease which include impairment in memory, orientation, language, visual processing, executive function, and praxis. Memory dysfunction is the first symptom that is recognized in Alzheimer's disease. Patients with memory loss initially present with the inability to remember recent events. In later stages, memory dysfunction extends to complete failures of recall for previously well-remembered information, such as the names of a patient's own spouse and children. In the later stage of Alzheimer's disease, the patient shows neuropsychiatric symptoms and behavioral disturbances - unawareness of deficits, apathy, psychosis, mood disorder, agitation, and Sundowning.

Alzheimer's disease has been classified clinically on the basis of the severity of the disease profile as mild, moderate, and severe forms. In clinical practice, Mini-Mental State Examination (MMSE), blood tests, Apolipoprotein E genotyping, computed tomography (CT), or magnetic resonance imaging (MRI) are performed for the diagnosis of Alzheimer's disease. Neuritic plaques and neurofibrillary tangles are the most important and characteristic pathogenic features in patients with Alzheimer's disease. Among Alzheimer's patients, <5% of cases show the early onset of Alzheimer's disease due to an inheritance pattern with a mutation in the Amyloid precursor gene (APP). This mutation causes the excess production of beta-amyloid peptides. It is suggested that the generation of Amyloid antibodies in humans with Alzheimer's disease appears to attenuate the disease process. In addition to the medication, what a patient requires is care, care from his/her near and dear ones. 

Written by:-
Dr. Sweta Soni
Assistant Professor
Department of Physiology
Mahatma Gandhi Medical College & Hospital
Jaipur, (Rajasthan)