Chapter 11-4: Alzheimer Disease (AD)

TEXTBOOK PRESENTATION

Typically, a family member brings in an older patient because of confusion, memory loss, or personality change. The patient may deny that a problem exists. Detection of dementia during casual conversation may be difficult early in its course; more formal assessment is frequently necessary.

DISEASE HIGHLIGHTS

1. AD most commonly occurs after the age of 65, although earlier presentations are possible.

2. Memory loss, behavioral or personality change, functional impairments, and social withdrawal are common early symptoms of AD.

3. Language disturbances

   1. In addition to those listed above, language disturbances are often present early in the course of the disease and often become severe with time.

   2. Language disturbances may include fluent aphasia, paraphasia, and word substitutions.

4. Later in the course of the disease, global cognitive impairment develops, and patients become unable to independently accomplish the most basic activities of daily living (ADLs).

   Although present, memory loss may not be the presenting symptom in patients with AD; rather, behavioral or personality changes, functional impairments, social withdrawal, or language disturbances may be the initial symptoms.

5. AD accounts for about 67% of cases of dementia.

6. Strictly speaking, the diagnosis of AD can only be made pathologically. That said, the diagnosis of AD is always made clinically.

7. All definitions of AD include the deterioration in a person’s ability to function independently. A patient’s level of functioning can be evaluated by assessing her ability to do the IADLs.

   1. IADLs include

      1. Cooking

      2. House cleaning

      3. Laundry

      4. Management of medications

      5. Management of the telephone

      6. Management of personal accounts

      7. Shopping

      8. Use of transportation

   2. Late in the disease, a patient’s ability to perform the ADLs often becomes compromised. These ADLs are

      1. Bathing

      2. Eating

      3. Walking

      4. Toileting and continence

      5. Dressing

      6. Grooming

8. The prognosis of AD is poor.

   1. Estimates of median survival have traditionally ranged from 5 years to 9 years with more recent data suggesting median survival close to 3 years with a range of 2.7 to 4 years.

   2. Patients with advanced dementia do especially poorly. In 1 cohort of patients with advanced dementia who were monitored for 18 months, 54.8% died, 41.1% developed pneumonia, and 85.8% developed an eating problem.

   3. Patients with AD also have a much worse prognosis after an acute illness. In the same cohort, the 6-month mortality rate for patients who had pneumonia was 46.7%.

EVIDENCE-BASED DIAGNOSIS

1. Diagnosing AD can be challenging because patients often have subtle symptoms early in the disease course.

   1. AD presents with self-reported memory loss in only a minority of patients.

      1. Memory loss reported by a spouse, relative, or close friend is more predictive of dementia than self-reported memory loss.

      2. Memory loss reported by a patient is still predictive dementia but may also be a sign of depression.

   2. Behavioral changes and mood changes are commonly recognized by family members.

   3. Clinicians may recognize behavioral changes such as increased anxiety, increased somatic complaints, or delusional thinking regarding illness as early symptoms of the ...