8.1 Understanding Dementia
Key Takeaways
- Dementia is a group of symptoms affecting memory, thinking, and behavior, not a normal part of aging
- Alzheimer's disease is the most common type of dementia (60-80% of cases); vascular dementia is second
- Short-term memory is affected first; long-term and procedural memory are preserved longer
- Sundowning causes increased confusion and agitation in the late afternoon and evening
- Always rule out physical causes (pain, infection, hunger, full bladder) before labeling a behavior 'just dementia'
What Dementia Is and Why CNAs Must Know It
Dementia is not a single disease. It is an umbrella term for a decline in memory, thinking, language, judgment, and behavior severe enough to interfere with daily life. Roughly 70-90% of long-term-care residents have some cognitive impairment, so almost every CNA shift involves dementia care. On the NNAAP/Prometric written exam, Care of Cognitively Impaired Residents is its own scored content area, and the skills evaluation triggers automatic-fail points around safety and dignity with these residents.
Dementia is NOT normal aging. Occasionally misplacing keys is aging; getting lost on a familiar street, forgetting a daughter's name, or losing the ability to dress is dementia. Memorize that distinction, because exam stems love to ask whether a behavior is "a normal change of aging."
Reversible vs. Irreversible Causes
A classic trap: not all confusion is dementia. Delirium is a sudden, fluctuating confusion with a reversible cause (urinary tract infection [UTI], dehydration, low oxygen, medication, fever). Dementia comes on slowly over months to years. If a resident who was calm yesterday is suddenly agitated and confused today, suspect delirium and report it immediately, do not assume the dementia "got worse."
| Feature | Delirium | Dementia |
|---|---|---|
| Onset | Sudden (hours-days) | Gradual (months-years) |
| Cause | Often reversible (UTI, drug, dehydration) | Progressive brain damage |
| Course | Fluctuates, worse at night | Steady decline |
| CNA action | Report STAT as a change | Ongoing supportive care |
Types of Dementia
| Type | Cause | Key Features |
|---|---|---|
| Alzheimer's disease (AD) | Amyloid plaques and tau tangles, brain-cell death | Most common (60-80%); gradual; recent-memory loss first |
| Vascular dementia | Reduced blood flow from strokes/TIAs | Second most common; abrupt, step-like decline |
| Lewy body dementia | Abnormal alpha-synuclein protein deposits | Visual hallucinations; tremor/stiffness; alertness swings |
| Frontotemporal dementia | Frontal/temporal lobe damage | Personality and language change, often before age 65 |
| Mixed dementia | More than one type together | Features of two or more; common in the very old |
Stages, Memory Patterns, and Behaviors
The Three Stages of Alzheimer's Disease
| Stage | Typical Duration | What the CNA Sees |
|---|---|---|
| Early (mild) | 2-4 years | Word-finding trouble, repeating questions, misplacing items; still mostly independent |
| Middle (moderate) | 2-10 years | Needs help with most activities of daily living (ADLs); wandering; sundowning; not knowing time or place |
| Late (severe) | 1-3 years | Total care, incontinence, loss of speech, cannot recognize family, bedbound, dysphagia |
How Memory Breaks Down
Dementia attacks memory in a predictable order, the most recent memories disappear first.
- Short-term memory (last few minutes): lost early; the resident forgets they just ate.
- Long-term memory (childhood, a late spouse): preserved much longer; this is why a resident may insist on "going to work" or "picking up the kids."
- Procedural memory (how to walk, hum a song, brush teeth): often intact until the late stage, which is why music and familiar motions still reach a resident who cannot speak.
Four terms appear on exams: aphasia (loss of language), agnosia (cannot recognize objects or faces), apraxia (cannot perform a learned movement despite intact muscles), and disorientation (confusion about time, place, or person).
Common Behaviors and Their Triggers
| Behavior | What It Looks Like | Frequent Triggers |
|---|---|---|
| Wandering | Walking with no clear destination | Boredom, looking for a bathroom, old routine, pain |
| Sundowning | Worse confusion/agitation late afternoon-evening | Fatigue, low light, hunger, overstimulation |
| Repetition | Same question again and again | Memory loss, anxiety, needing reassurance |
| Catastrophic reaction | Sudden screaming, crying, hitting | Overstimulation, being rushed, too many demands |
| Shadowing | Following the CNA everywhere | Fear of being alone |
| Hoarding/rummaging | Hiding food or items | Insecurity, lifelong habit |
The Golden Rule: Look for a Physical Cause First
Before you treat a new behavior as "just the dementia," rule out a fixable cause. Pneumonic clue many programs teach: a sudden behavior change is often pain, infection (UTI), constipation, hunger, thirst, a full bladder, or being too hot or cold. A resident who suddenly becomes combative during care may simply hurt. Report the change; the nurse may find a treatable problem. This habit prevents unnecessary chemical and physical restraints, which are tested heavily.
Worked Scenario
A resident with middle-stage Alzheimer's who normally eats breakfast quietly suddenly hits a CNA's hand, pulls away, and grimaces during morning care. A new CNA might chart "combative due to dementia." The skilled CNA pauses and asks why: Is there a new pressure injury? A full bladder? Constipation for three days? A UTI causing burning? Did the resident sleep? In this case the nurse later finds a UTI; once treated, the combative behavior disappears. The lesson the exam rewards: a new behavior is a symptom to investigate and report, not a personality flaw to manage with force.
Common Exam Traps for This Section
- "It is normal for an 80-year-old to forget their daughter's name", false; that is dementia, not aging.
- "Sudden confusion overnight means the dementia worsened", false; suspect delirium and report.
- "Long-term memory fails before short-term", false; recent memory goes first.
- "Lewy body dementia is best known for early memory loss", false; its hallmarks are visual hallucinations and movement problems.
Quick Reference: Spotting the Dementia Type
- Gradual memory loss, plaques and tangles -> Alzheimer's.
- Step-wise decline after strokes -> vascular.
- Vivid visual hallucinations plus stiffness -> Lewy body.
- Personality and language change before age 65 -> frontotemporal.
Knowing these one-line cues lets you answer type questions in seconds and frees time for the scenario items, which carry the most weight in the cognitive-care portion of the test.
A resident with stable mild dementia suddenly becomes very confused and agitated overnight. What should the CNA suspect FIRST?
Which type of memory typically remains intact the LONGEST in a person with dementia?
Which type of dementia is the second most common after Alzheimer's disease?