Diagnosis

Diagnosis

A definitive test to diagnose Alzheimer's disease, even in patients showing signs of dementia, has not yet been developed. A number of expert groups have developed criteria to help diagnose Alzheimer's disease and rule out other disorders. A diagnosis often involves answering questions about the patient:

• Do psychologic tests indicate dementia?
• Does the patient have deficits in two or more areas of mental functioning (such as language, motor skills, and perceptions)?
• Has memory and mental functions gotten progressively worse?
• Is consciousness disturbed? (It is not in Alzheimer's disease.)
• Is the patient over age 40?
• Are other medical or physical conditions present that could account for the same symptoms?
• Are daily activity impaired or has the behavior changed?
• Is there a family history of Alzheimer's disease?
• Are there other symptoms, such as depression, insomnia, incontinence, delusions, hallucinations, dramatic verbal, emotional or physical outbursts, sexual disorders, and weight loss?

Other steps involved in making a decision include laboratory tests (EEG and possibly tests to rule out other diseases) and psychological testing to determine the presence of dementia.

Ruling out Conditions of Normal Aging that Can Cause Alzheimer's-like Symptoms

Although some memory impairment occurs in many people as they age, only some of these people develop Alzheimer's disease. Many similar symptoms can occur in healthy older individuals from other conditions associated with aging:

• Fatigue
• Grief or depression
• Illness
• Vision or hearing loss
• The use of alcohol or certain medications
• Simply the burden of too many details to remember at once

Ruling Out Other Causes Memory Loss or Dementia

The first step in diagnosing Alzheimer's disease is to rule out other conditions that might cause memory loss or dementia. There are a number of causes for dementia in the elderly besides Alzheimer's disease:

• Vascular dementia (abnormalities in the vessels that carry blood to the brain)
• Lewy bodies variant (LBV), also called dementia with Lewy bodies
• Parkinson's disease
• Frontotemporal dementia