Dementia

What is dementia?

Dementia is not a specific disease but a general term used to describe a cognitive decline that interferes with daily life. It generally involves memory problems but can also affect thinking, communication, and decision-making. Dementia is caused by various diseases or injuries that affect the brain, such as Alzheimer’s disease or stroke.

Alzheimer’s disease is the most common type of dementia, accounting for an estimated 60–80% of cases. Other forms include vascular dementia (occurring after a stroke), Lewy body dementia (associated with abnormal protein deposits in the brain), and frontotemporal dementia (involving damage to the frontal and temporal lobes).

Dementia is more common in older adults but is not a normal part of aging. Early signs can be mild, such as trouble keeping track of a purse or wallet, paying bills, planning meals, remembering appointments, or navigating outside the neighborhood. As dementia progresses, symptoms become more severe and can significantly impact the ability to live independently.

What causes dementia?

Dementia results from damage to brain cells, affecting their ability to communicate and leading to impaired memory, thinking, behavior, communication, and emotions. Major types include:

  • Alzheimer’s disease and related dementias: Build-up of amyloid plaques and tau tangles, loss of nerve-cell connections, and cell death.
  • Vascular dementia: Damage to blood vessels from strokes or other blood-supply problems.
  • Dementia with Lewy bodies: Accumulation of Lewy body proteins in nerve cells.
  • Frontotemporal dementia: Progressive loss of nerve cells in the frontal and temporal lobes, affecting personality, behavior, and language.
  • Mixed dementia: Brain changes from two or more types of dementia, most often Alzheimer’s plus vascular dementia.

Other potential causes and risk factors include:

  • Genetic factors: Family history increases risk.
  • Head injuries: Severe or repeated brain trauma.
  • Lifestyle and heart health: Smoking, high blood pressure, high cholesterol, and diabetes.
  • Age: Risk increases significantly after age 65.
  • Other medical conditions: Parkinson’s disease, Creutzfeldt-Jakob disease, Huntington’s disease, normal-pressure hydrocephalus, vitamin deficiencies, chronic traumatic encephalopathy.
  • Medication side effects: Certain drugs such as diphenhydramine or oxybutynin can worsen memory.

What are the symptoms of dementia?

Symptoms vary by the part of the brain affected and the dementia type. Common early and progressive symptoms include:

  • Memory loss, starting with recent events and worsening over time
  • Trouble with complex tasks like paying bills or planning meals
  • Poor reasoning or judgment, leading to safety risks
  • Getting lost in familiar places
  • Difficulty following conversations or finding the right words
  • Changes in mood, personality, or behavior (irritability, depression, anxiety, impulsivity)
  • Misplacing items and inability to retrace steps
  • Loss of interest in hobbies and social activities
  • Balance and movement problems, especially in Lewy body dementia
  • Hallucinations, delusions, or paranoia in some types

In advanced stages, individuals may need help with eating, dressing, and personal care, and may require constant supervision.

How is dementia diagnosed?

Diagnosis involves a combination of assessments to measure cognitive function and rule out other causes:

  • Patient history: Detailed symptoms review, family history, and daily functioning changes.
  • Physical exam: Checks for other medical causes, including heart and neurological exams.
  • Cognitive tests: Assess memory, problem-solving, attention, and language skills.
  • Laboratory tests: Blood tests to rule out vitamin deficiencies, thyroid issues, and other conditions.
  • Brain imaging: MRI or CT scans to detect strokes, tumors, bleeding, or structural changes; PET scans to identify amyloid or tau deposits.
  • Psychiatric evaluation: Determines if mental health conditions like depression contribute to symptoms.
  • Genetic testing: Considered when there is a strong family history or early-onset dementia.

How is dementia treated?

While there is no cure for most dementias, treatments focus on managing symptoms, maintaining independence, and planning for the future.

Medications

  • Cholinesterase inhibitors (donepezil, rivastigmine, galantamine) to improve memory and thinking.
  • Memantine to regulate glutamate activity in moderate to severe Alzheimer’s disease.
  • Lecanemab (Leqembi) infusion to target and remove beta-amyloid in early Alzheimer’s disease.
  • Other drugs for depression, agitation, hallucinations, or sleep problems.

Therapies

  • Cognitive stimulation therapy: Activities and exercises to improve mental functions.
  • Occupational therapy: Home modifications and behavior management to maintain independence.

Lifestyle Changes and Home Safety

  • Regular exercise to support muscle strength, mood, balance, and heart health.
  • Balanced diet to support brain health and proper nutrition.
  • Home modifications (fall prevention, safety locks, monitoring) to reduce risks and wandering.
  • Consistent nighttime routines to improve sleep quality.

Advanced Care Planning

  • Legal and financial planning early after diagnosis to ensure wishes are respected.
  • End-of-life care planning in later stages to guide medical and personal decision-making.

Sources

  • What is Dementia? Alzheimer’s Association. Accessed Apr. 24, 2024.
  • What Is Dementia? Symptoms, Types, and Diagnosis. National Institute on Aging. Accessed Apr. 24, 2024.
  • Dementias. National Institute of Neurological Disorders and Stroke. Accessed Apr. 24, 2024.
  • Dementia. Merck Manual. Accessed Apr. 24, 2024.
  • What is Dementia? Centers for Disease Control and Prevention. Accessed Apr. 24, 2024.