Alzheimer's disease resident survival guide

Alzheimer's disease Resident Survival Guide Microchapters
Overview
Causes
Diagnosis
Treatment
Do's
Don'ts

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Fahimeh Shojaei, M.D., Moises Romo M.D.

Synonyms and keywords:Alzheimer's disease management, Alzheimer's disease workup, Alzheimer's disease approach, approach to Alzheimer's disease, Alzheimer's disease treatment

Overview

Alzheimer's disease is the most common cause of dementia among older people. Dementia is a loss of thinking, remembering, and reasoning skills that interfere with a person's daily life and activities. The diagnosis of Alzheimer's disease (AD) is made on the basis of clinical criteria described by either the National Institute on Aging and the Alzheimer's Association (NIA-AA) or DSM-V (Diagnostic and Statistical Manual of Mental Disorders, fifth edition). There is no known cure for Alzheimer's disease (AD). Available treatments offer relatively small symptomatic benefit but remain palliative in nature. Current treatments can be divided into pharmacological, psychosocial, and caregiving.

Causes

Life-Threatening Causes

Life-threatening causes include conditions that may result in death or permanent disability within 24 hours if left untreated.

• Alzheimer's disease is not a life-threatening condition that may result in death or permanent disability within 24 hours if left untreated.

Common Causes

While there is no direct cause for the development of Alzheimer's disease, there are several factors that may contribute to its acquisition:

• Chromosomal
  • Down syndrome
    • Trisomy 21
    • Overexpression of amyloid precursor protein (APP) on chromosome 21
    • Develop the neuropathologic hallmarks of AD after 40 years of age
• Familial
  • Late-onset familial (AD2)
    • APOE gene:
    • TREM2 gene:
    • PLD3 gene
    • UNC5C gene
    • AKAP9 gene (in African-Americans only)
  • Early-onset familial AD (AD1, AD3, AD4)
    • PSEN1 gene:
    • PSEN2 gene:
    • APP gene:

• Unknown (includes genetic/environment interactions)
  • Multifactorial
    • Aging
    • Genetic predisposition
    • Exposure to one or more environmental agents including head trauma, low level of education, viruses, and/or toxins

Diagnosis

Shown below is an algorithm summarizing the diagnosis of amnesia according to the the American Academy of Neurology guidelines:

Patient with amnesia

Acute onset

Chronic onset

Measure vitamin B12, and folate, and TSH

Abnormal?

Yes

Vitamin deficiency, hypothyroidism

Fluctuating course, inattention, disorganized thinking, or altered level of consciousness?

Positive for SIGE CAPS questionary?

Yes

Depression

Yes

No

Severe impairment in social functioning?

No

Normal aging

Delirium

Dementia

Take history and perform physical examination

Take history and perform physical examination

History of head trauma?

Yes

No

Concussion, post-concussive amnesia

Measure urine toxicology, CBC, creatinine, electrolytes, and glucose to reveal cause

Initial short term memory loss

Vascular risk factors, imaging evidence of cerebrovascular involvement

Young age, behavioral symptoms or language impairment

Bradikinesia or features of parkinsonism, fluctuating cognition, [[visual hallucinations]]

Dementia occurring 1 year after onset of Parkinson disease

Alzheimer disease

Vascular dementia

Frontotemporal dementia

Dementia with Lewy bodies

Parkinson's disease

Treatment

Shown below is an algorithm summarizing the treatment of Alzheimer's disease according to the American Academy of Neurology guidelines:

Patient with diagnosed Alzheimer's disease

Mild to moderate

Moderate to severe

Initiate therapy •Donepezil. 5 mg once daily; titrate 10 mg once daily •Galantamine (solution). 4 mg twice daily; titrate to 8 mg twice daily •Galantamine (ER capsules). 8 mg once daily; titrate to 16 mg once daily •Rivastigmine (patch). 4.6 mg once daily; titrate to 9.5 mg once daily •Rivastigmine (oral). 1.5 mg twice daily; titrate to 6 mg twice daily

Adverse event Consider switch to a different ChEI

Disease progression Consider high dose or switch to a different ChEI

Initiate therapy •Donepezil. 5 mg once daily; titrate 10 mg once daily •Rivastigmine (patch). 4.6 mg once daily; titrate to 9.5 mg once daily •Memantine. 5 mg once daily; titrate to 10 mg twice daily or Memantine XR. 7 mg once daily; titrate to 28 mg once daily •Combination ChEI+ Memantine. 7 mg twice daily or 10 mg once daily (ER); titrate to 10 mg twice daily or 28 mg once daily (ER)

Monitor and reevaluate therapy Monitor every 3-4 months and titrate dose as needed

Adverse event Consider switch to a different therapy

Disease progression Consider higher dose or switch to a different therapy

Discontinue therapy When all cognitive function and functional abilities are lost at terminal stages of AD

Recommendations for maintaining brain health in elderly patients with and without Alzheimer's Disease
Consider following a Mediterranean-style diet, with fish, vegetables, legumes, fruit, cereals, unsaturated fatty acids (e.g., olive oil), and a limited amount of meat or dairy products. Consider taking supplements containing omega-3 (particularly docosahexaenoic acid), B-complex vitamins (including B12, B6, folic acid), and vitamin E. Keep alcohol intake to a low-to-moderate level (e.g., one glass of wine per day with dinner). Engage in regular physical activity. Maintain leisure and social activities – keep socially engaged. Continue or start activities that help to stimulate the brain, e.g., Tai Chi, dancing, puzzles. Become educated about dementia and seek support from others with dementia, e.g., the Alzheimer's Association, Keep Memory Alive, and other community groups. Include music in daily life – listening to music, playing an instrument, singing. Maintain regular sleep patterns. Manage stress – stop doing things if they are becoming too stressful (e.g., volunteer work, answering the telephone), keep to a regular daily schedule, and include relaxing activities (e.g., playing with pets, massage, and aromatherapy).
Do not modify

Dos

• Perform laboratory testing to exclude potentially reversible causes of amnesia. Initial tests should include a CBC, urine toxicology, thyroid function, folate, and vitamin B12 level.
• When performing cognitive assessment, use tests such as MMSE, Mini-cog, MoCA, SIB-8, and AD8.
• When determining level of independence and level of disability, use test such as ADCS–ADL.
• When determining the level of behavioral symptoms, use the NPI-Q test.
• Identify primary caregiver and assess their health, as well as adequacy of family and other support systems.
• Neuroimaging may diagnose vascular disease, normal pressure hydrocephalus, tumors, abscess.
• Perform a minimental status test on physical examination and pay special attention to concentration domain. Minimental testing has the potential to distinguish mild cognitive impairment from dementia.
• Always have in mind depression as a possible cause of memory impairment. Depression is common cause of amnesia; a SIGE CAPS evaluation may disclose an underlying mood disorder..

Don'ts

• If alcoholism and thiamine deficiency is suspected, do not administer glucose before thiamine. Administration of glucose before thiamine may lead to Wernicke encephalopathy.