Alzheimers disease

The article provides a comprehensive overview of Alzheimer's Disease (AD), a common neurodegenerative disorder in older individuals. It discusses the characteristics, diagnostic criteria, and treatment options for AD. Key points include the identification of AD as the primary cause of dementia in the elderly, details on how to diagnose the disease, and an examination of the available treatments, focusing on cholinesterase inhibitors and memantine. The article also outlines the limitations of current therapies, emphasizing that there is no cure for AD. References from various medical studies and journals support the information provided.

Overview of Alzheimer's Disease

Alzheimer disease (AD) is a neurodegenerative disorder of unknown cause which usually affects older people (>70 years age). AD is the most common cause of dementia in old ages. Early onset AD (<65 years age) is unusual and usually inherited. The most essential and earliest clinical manifestation of the disease is selective memory impairment.

Diagnostic Criteria for Alzheimer's Disease

Criteria for diagnosis of AD include the following; dementia interferes with patient’s ability to function at usual activities and not explained by delirium or major psychiatric disorder. Cognitive impairment involves a minimum of two of either impaired ability to acquire and remember new information, impaired reasoning and handing of complex tasks, or impaired visuospatial abilities. Impaired language functions and personality changes are also common in AD.

Treatment Options and Limitations

There is no cure or disease modifying therapy (DMT) for AD. The disease inevitably progresses in all patients. Treatments could ameliorate some symptoms of the disease.

Cholinesterase Inhibitors in AD Management

The majority of patients with newly diagnosed AD are offered a trial of a cholinesterase inhibitor for symptomatic treatment of cognitive and global dysfunctions. Cholinesterase inhibitor slowly prolongs the progression of the disease and showed better results in patients with mild dementia. Cholinesterase inhibitors include donepezil, galantamine, or rivastigmine. Caution should be taken when any of the three drugs are used in combination with drugs that induce bradycardia or alter atrioventricular (AV) nodal conduction. Nausea and diarrhea are common side effects of cholinesterase inhibitors. For responding patients, decisions on long term use of these agents depends on the patient's treatment response and long-term goals of care.

Management Strategies for Non-Responders to Cholinesterase Inhibitors

Patients who do not respond to cholinesterase inhibitors could choose to stop treatment after a six-month trial. An alternative approach is with memantine which could be added or substituted in patients with severe dementia.

References

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