Almost everyone forgets a name or misplaces their keys now and then, and memory naturally slows a little with age. Dementia is different. It is a decline in memory and thinking serious enough to interfere with daily life. Knowing the difference helps families seek an evaluation early, when treatable causes can be found and planning is easier.
What dementia is
Dementia is an umbrella term, not a single disease. The most common types are:
- Alzheimer’s disease, the most common cause, often starting with trouble remembering recent events
- Vascular dementia, caused by reduced blood flow to the brain, often after strokes
- Lewy body dementia, which can cause visual hallucinations, fluctuating alertness and movement problems
- Frontotemporal dementia, which often affects personality, behavior or language first and can begin in the 50s or 60s
- Mixed dementia, a combination of types
Normal aging vs possible dementia
| Normal aging | Possible dementia |
|---|---|
| Occasionally forgetting a name but remembering it later | Frequently forgetting recent conversations or events and not recalling them later |
| Sometimes losing things but retracing steps to find them | Putting things in unusual places and being unable to retrace steps |
| Occasionally searching for the right word | Frequently struggling with words, stopping mid-sentence or repeating stories |
| Making an occasional bad decision | Showing poor judgment, such as with money or scams |
| Needing help with new technology | Difficulty with familiar tasks, such as cooking a usual recipe or paying bills |
| Getting confused about the day of the week but working it out | Losing track of dates, seasons or the passage of time |
| Feeling tired of social obligations sometimes | Withdrawing from hobbies, work and social activities |
The 10 warning signs
- Memory loss that disrupts daily life
- Difficulty planning or solving problems
- Trouble completing familiar tasks
- Confusion about time or place
- Difficulty with visual and spatial relationships, such as judging distance
- New problems with words in speaking or writing
- Misplacing things and being unable to retrace steps
- Poor judgment
- Withdrawal from work or social activities
- Changes in mood and personality, such as becoming confused, suspicious, anxious or depressed
Mild cognitive impairment
Some people have mild cognitive impairment (MCI): noticeable memory or thinking problems that are greater than expected for age but do not significantly affect independence. MCI increases the risk of developing dementia, but not everyone with MCI progresses, and some people improve.
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Conditions that mimic dementia
A full medical evaluation is important because some causes of memory problems are treatable:
- Depression and anxiety
- Vitamin B12 deficiency
- Underactive thyroid
- Medication side effects, especially sleeping pills, anticholinergic drugs and some pain medicines
- Sleep apnea and poor sleep
- Hearing or vision loss
- Urinary or other infections, which can cause sudden confusion (delirium) in older adults
- Normal pressure hydrocephalus, a buildup of fluid in the brain
- Heavy alcohol use
Sudden confusion over hours or days is not typical of dementia and needs urgent medical assessment.
How dementia is diagnosed
Diagnosis usually involves:
- A detailed history from the person and someone who knows them well
- Brief memory and thinking tests, such as the MoCA or Mini-Cog
- A physical and neurological exam
- Blood tests to check for treatable causes
- Brain imaging (CT or MRI)
- In some cases, detailed neuropsychological testing, PET scans or tests for Alzheimer’s proteins in spinal fluid or blood
Blood tests that detect Alzheimer’s-related proteins are becoming more widely available and can help specialists reach a diagnosis.
Medicare’s Annual Wellness Visit includes a cognitive assessment, and Medicare also covers a dedicated cognitive assessment and care planning visit when problems are suspected.
Treatment options
There is no cure for most types of dementia, but treatment can help:
- Cholinesterase inhibitors (donepezil, rivastigmine, galantamine) and memantine can help memory and thinking symptoms for a time.
- Anti-amyloid antibody treatments, lecanemab and donanemab, are approved for people with mild cognitive impairment or mild dementia due to confirmed Alzheimer’s disease. They slow decline modestly in clinical trials. They require regular infusions and MRI monitoring because of a risk of brain swelling or bleeding, and they are not suitable for everyone.
- Treating vascular risk factors such as high blood pressure, diabetes and high cholesterol can help slow vascular dementia.
- Non-drug approaches, including routines, cognitive stimulation, exercise and caregiver support, improve quality of life.
Reducing your risk
Research suggests that a significant share of dementia cases may be linked to modifiable risk factors. Steps that may lower risk include:
- Controlling blood pressure, especially in midlife
- Staying physically active
- Treating hearing loss, for example with hearing aids
- Not smoking and limiting alcohol
- Managing diabetes and cholesterol
- Staying socially and mentally engaged
- Protecting your head from injury
- Getting enough sleep and treating sleep apnea
- Treating depression
When to see a doctor
If you or a family member notice memory or thinking changes that are new and affect daily life, make an appointment with a primary care doctor. Bring someone who knows the person well, along with a list of medicines and examples of the changes. Early evaluation allows treatable causes to be found and gives time for legal, financial and care planning.
The bottom line
Occasional forgetfulness is normal. Memory loss that disrupts daily life, trouble with familiar tasks, confusion about time or place, and personality changes are not. Get checked early. Some causes are reversible, and for Alzheimer’s disease, new treatments work best in the earliest stages.
This article is for general information and does not replace medical advice.