Older patients who have difficulties with memory may have Alzheimer disease, or they may have another condition with similar symptoms.
Dementia is a term used to describe a decline in mental abilities, including memory, language, and logical thinking, that is severe enough to affect daily living. When older people start to have these types of symptoms, they often worry about Alzheimer disease. Alzheimer disease is a neurodegenerative dementia, which means that the dementia causes loss of brain tissue and is not reversible. Vascular dementia is another type, caused by poor blood flow to the brain, and it is also not reversible. Dementia due to Alzheimer disease and vascular dementia can occur together.
What Conditions Act Like Neurodegenerative Dementia?
Many conditions other than Alzheimer disease or vascular dementia can affect a person’s memory, language, and logical thinking. Some of these conditions can be temporary and others are permanent. When a person is evaluated for memory problems or problems related to not thinking clearly, a number of conditions should be considered as the possible cause. Delirium is one cause, and it can be related to medication side effects, recreational drug use, toxins, endocrine disorders such as hypothyroidism, or metabolic problems like hyponatremia. Other possible causes include depression; sleep disturbances; medication side effects; hearing and vision loss; deficiencies in nutrients such as vitamin B12, folic acid, and thiamine; long-term alcohol misuse; normal pressure hydrocephalus; chronic infections such as neurosyphilis or HIV/AIDS; brain masses; subdural hematoma; autoimmune encephalitis; and cerebral vasculitis.
Evaluation for Dementia and Reversible Causes of Dementia
Patients evaluated for memory loss and difficulties with language and logical thinking are asked questions about when they first noticed their symptoms, how severe the symptoms are, and how the symptoms affect the patient’s everyday activities. With the patient’s permission, the clinician may ask family and friends about what they’ve observed about the patient’s memory, speech, and thinking. Medication use is reviewed to determine if the symptoms could be a side effect. Screening tests for depression should be given, as should verbal and written tests to evaluate a patient’s cognitive function. Laboratory tests and imaging of the brain may be obtained. Patients may also be referred for evaluation of hearing, vision, neuropsychiatric testing, or psychological assessment.
Symptoms of memory loss and difficulty with language and logical thinking often are due to neurodegenerative dementias like Alzheimer disease and vascular dementia, which are common and incurable. Reversible causes can be treated and should be considered for patients having difficulty with memory or problems with thinking clearly. For example, depression can be treated with antidepressants, vitamin B12 and thyroid hormone can be supplemented, and eyeglasses and hearing aids can be obtained. It should never be assumed that an older patient with memory loss has Alzheimer disease or another neurodegenerative dementia without first considering reversible causes of dementia.
Box Section Ref IDFor More Information
To find this and other JAMA Patient Pages, go to the For Patients collection at jamanetworkpatientpages.com. A JAMA Patient Page on Alzheimer disease was published in the April 14, 2015, issue.
Conflict of Interest Disclosures: None reported.
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