dementia
Meaning of dementia: An acquired, progressive decline in memory, reasoning and other thinking abilities severe enough to interfere with daily life.
Definition of dementia
Dementia is a general term for a lasting decline in memory, reasoning, language or other thinking abilities that is severe enough to interfere with everyday activities. It describes a pattern of symptoms rather than a single disease, and several distinct underlying conditions can produce it. Dementia is not a normal part of aging, although the risk of developing it rises with age.
Common underlying causes
Dementia is a syndrome, so the useful question is always which disease is producing it. The main causes differ in what they damage first, which is why their early symptoms differ.
| Cause | Characteristic early features |
|---|---|
| Alzheimer disease | Memory for recent events, word-finding difficulty |
| Vascular dementia | Slowed thinking, planning difficulty, often stepwise change |
| Lewy body dementia | Fluctuating alertness, visual hallucinations, parkinsonism |
| Frontotemporal dementia | Personality and behavior change, or language loss, memory relatively spared |
How it differs from normal aging
Occasionally forgetting a name and recalling it later is ordinary. Dementia involves losses that are persistent, progressive and disruptive: repeatedly forgetting recent conversations, becoming lost somewhere familiar, or struggling with tasks that were previously routine, such as managing money.
Conditions that can mimic it
- Delirium comes on over hours or days and fluctuates, whereas dementia develops over months or years.
- Depression can slow thinking and impair concentration in a way that resembles cognitive decline.
- Thyroid disorders and vitamin B12 deficiency can produce cognitive symptoms and are identifiable on testing.
Used in a sentence
The neurology consultation was requested to evaluate the patient for progressive dementia affecting memory and daily function.
Good to know
Dementia describes a gradual, sustained decline, which distinguishes it from delirium, an acute and often reversible state of confusion that develops over hours to days.
Word origin
Where “dementia” comes from
Formed from Latin de-, meaning away or from, combined with mens, mentis, meaning mind, together indicating a departure from normal mental function.