Causes, Consequences, and Treatment of Dementia
Managing Alzheimer's Disease and Other Causes of Cognitive Decline
Oct 11, 2008
Dementia is the gradual, progressive, and irreversible decline of cognitive function involved in attention, memory, and other higher thought processes. It typically affects the elderly population and presents many challenges for these individuals and their loved ones. The condition has many causes, but its consequences and treatments are generally similar.
Causes of Dementia
- Alzheimer's Disease: When one thinks of dementia, he or she often thinks of Alzheimer's disease. This is the most common cause of dementia, which involves the formation of neurofibrillary tangles, beta-amyloid deposits, and plaques that cause the brain to shrink in size (atrophy).
- Vascular Dementia: The second most common cause of dementia is vascular dementia. This basically occurs when strokes, involving small or large vessels, affect parts of the brain that contribute to cognitive function.
- Lewy Body Dementia: Lewy body dementia, the third most common cause of dementia, involves deposits of alpha-synuclein protein. These Lewy bodies are also implicated in Parkinson's disease, which may or may not coexist with dementia.
- Other Causes: The remaining causes of dementia include but are not limited to HIV-associated dementia, Huntington's disease, Parkinson's disease, Creutzfeldt-Jakob disease, and progressive supranuclear palsy.
Consequences of Dementia
A variety of mental functions can change permanently as a result of dementia. Memory loss is often the first sign of dementia. A patient with dementia may then have trouble with communication (aphasia), decision-making, and/or identification of objects despite normal sensory function (agnosia). In later stages of dementia, the individual gradually has difficulties with motor movements (apraxia), such as those for walking, eating, bathing, and other activities of daily living. Throughout this ongoing process of decline, the individual can become frustrated and develop emotional problems.
These direct effects can lead to a number of other consequences. For example, memory loss can result in home safety risk, such as not turning off a stove, or in difficulty with simple tasks, such as finding a certain room at home. Limitations in movement increase the likelihood of medical problems, including but not limited to trauma from falls, pressure ulcers from prolonged immobility in one position, and malnutrition from not being able to eat or drink. These medical issues typically occur in intermediate and late stages of dementia and are often the cause of death in patients with dementia.
Principles of Treatment
Because dementia is irreversible, treatment does not restore prior cognitive function. Rather, it focuses on slowing the progression of disease and enhancing the quality of life. Certain causes of dementia can be addressed with medications, such as donepezil for Alzheimer's disease. Otherwise, the patient should have access to leisure activities, appropriate for his or her level of function, within safe and familiar surroundings. He or she must also have assistance from caregivers, whether they are family members or nursing home staff. All of these measures should be ongoing until the patient's end of life.
References
- Merck Manual - Delirium and Dementia
- Feldman, Howard H., et al. "Diagnosis and Treatment of Dementia: 2. Diagnosis." Canadian Medical Association Journal. 178.7 (March 25, 2008): 825-36.
