Age is the greatest risk factor for memory loss and dementia, defined as a cognitive decline that interferes with independent functioning. By age 45, the objective memory performance of the average individual is lower than it was during their twenties, but for most, these mental slips are minimal and do not progress.
For those with a family history of Alzheimer disease (AD), these age-related memory complaints cause considerable anxiety: patients worry that their normal aging symptoms are the initial indication of a progressive cognitive impairment that they have observed in their relatives.
Differential diagnosis and assessment
AD is the most common cause of dementia. It has a gradual onset and progression and leads to abnormal protein deposits—amyloid plaques and tau tangles—that accumulate in the patient’s brain regions that control thinking and memory. However, many other conditions can cause dementia, such as depression, medication adverse effects, thyroid imbalances, and other medical illnesses. Treating these underlying medical conditions may occasionally cure a reversible dementia or lead to partial symptom improvement.
Other irreversible neurodegenerative diseases that cause dementia include Lewy body disease, vascular dementia, and frontotemporal degeneration. Even if there is no cure for the underlying cause of a dementia, treatments are available that stabilize symptoms and help people remain healthier longer.
A clinical assessment of cognitive issues includes a search for risk factors, such as a smoking history, lack of sleep, prior head trauma, or history of untreated high blood pressure or high cholesterol. A detailed inventory of the patient’s medications is essential. Many prescription and over-the-counter drugs for allergies (diphenhydramine or Benadryl) or sleep (eg, Sominex which also contains diphenhydramine) can impair cognition.
Sedating medicines, narcotic agents, histamine H2-receptor antagonists (eg, famotidine or Pepcid, cimetidine or Tagamet) for gastrointestinal problems, cardiac medications such as digoxin and beta-blockers, corticosteroids, non-steroidal anti-inflammatory agents (eg, naproxen or Aleve, ibuprofen or Motrin), and antibiotics are all among the list of medicines that may contribute to symptoms.
A mental status assessment will help determine the patient’s degree of cognitive impairment, as well as the presence of depression or anxiety that can worsen memory. A brief evaluation of cognitive abilities will determine degree of cognitive impairment, and neuropsychological cognitive testing may be ordered to detail these deficits through neuropsychological testing.
A physical and neurological examination and screening blood tests for thyroid, metabolic, and other possible abnormalities are recommended to uncover medical causes of confusion. To ensure that a tumor, stroke, or other brain abnormality is not present, a computed tomography (CT) or magnetic resonance imaging (MRI) scan is performed.
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