Guide to Dementia: Symptoms, Diagnosis & Care Tips

Dementia is an umbrella term for conditions that affect memory, thinking, and daily functioning. It is not a single disease, but a set of symptoms caused by different brain disorders such as Alzheimer’s disease, vascular dementia, Lewy body dementia, and frontotemporal dementia.

Alzheimer’s disease is the most common type of dementia, making up 60–80% of cases. It is a progressive brain disorder that causes memory loss, confusion, and difficulties with communication and reasoning. It starts with mild memory issues and advances to severe cognitive decline, eventually affecting independence and daily activities.

Dementia is the general term for cognitive decline, while Alzheimer’s is a specific disease that causes dementia. Put simply: all Alzheimer’s is dementia, but not all dementia is Alzheimer’s.

• Alzheimer’s disease – the most common type, linked to amyloid plaques and tau tangles in the brain.
• Vascular dementia – caused by reduced blood flow or strokes, leading to stepwise cognitive decline.
• Lewy body dementia – characterized by abnormal protein deposits, visual hallucinations, and Parkinson-like symptoms.
• Frontotemporal dementia – often begins at a younger age (45–65) and affects personality, behavior, and language.
• Mixed dementia – when more than one type of dementia occurs simultaneously, often Alzheimer’s with vascular dementia.

DIAGNOSIS SPECIFIC INFORMATION

Dementia is a group of symptoms, but the underlying causes vary. The differences are based on:

• The part of the brain affected (e.g., frontal lobes vs. temporal lobes)
• The cause of brain damage (e.g., stroke, protein buildup, trauma, or genetics)
• The way symptoms progress (gradual memory decline vs. sudden changes)

Classifying dementia into different types helps with diagnosis, treatment planning, and caregiving strategies.

Generally, dementia progresses through stages—cognitive impairment, early, middle, and late—each bringing increasing challenges in memory, behavior, communication, and daily functioning.

Understanding the stages helps families prepare for medical needs and caregiving support.

While progression can vary greatly from person to person, the type of dementia diagnosed also influences how and when different symptoms appear. 

These are some of the changes that can be expected. 

Stage 1: Cognitive Impairment

• Forgetfulness and misplaced items
• Slowed speech
• Gait impairment and poor coordination
• Depression, lack of personal care, collecting/hoarding
• Emotional changes such as agitation and mood swings

Stage 2: Early Stages

• Repeating themselves, difficulty with reading or arithmetic
• Substituting words, incomplete sentences
• Parkinsonism, clumsiness, frequent falls, poor coordination
• Wandering, delusions, paranoia, confusion
• Anxiety, agitation, mood swings

Stage 3: Middle Stages

• Unable to dress without assistance, loss of name recognition, reduced spatial awareness
• Incomprehensible speech
• Visual impairment (depth/contrast), severely reduced motor skills
• Wandering, anxiety, hallucinations, paranoia, sleep apnea
• Apathy and aggression

Stage 4: Late Stages

• No short-term memory, some long-term memory, no facial recognition
• Gibberish speech
• Incontinence, Parkinsonism, difficulty eating, swallowing, drinking
• Wandering behavior
• Aggression and mood swings

For more specific details on the stages of the different types of dementia, visit our: Stages of Dementia Page.

Stages of Alzheimer's Disease

Stages of Vascular Dementia

Stages of Lewy body Dementia

Stages of Fronto-Temporal Lobe Dementia 

• Alzheimer’s disease – Memory loss is the earliest and most prominent symptom. People may forget recent events first, then gradually lose long-term memory, recognition, and independence.
• Vascular dementia – Progression is often “step-like” rather than gradual. Symptoms may suddenly worsen after strokes or small vessel blockages, leading to changes in thinking, mood, or physical coordination.
• Lewy body dementia – Fluctuations are more common. A person may seem clear one day and confused the next. Visual hallucinations, sleep disturbances, and Parkinson-like movement issues appear earlier compared to Alzheimer’s.
• Frontotemporal dementia (FTD) – Instead of memory problems in the beginning, personality, judgment, and language are affected first. Memory often remains intact in the early stages but declines in later stages.
• Mixed dementia – Many people experience symptoms of more than one type (commonly Alzheimer’s plus vascular dementia), leading to a combination of memory decline, physical changes, and mood or behavior symptoms.

Compare Symptoms by Diagnosis & Stage

Dementia can be caused by damage to brain cells from strokes, abnormal protein buildup, traumatic brain injury, or other medical conditions. Age, genetics, and cardiovascular health are also major risk factors.

The exact cause of Alzheimer’s is not fully understood. Scientists believe it involves abnormal protein deposits in the brain—known as amyloid plaques and tau tangles—as well as genetic risk factors and aging.

Dementia itself is not directly hereditary, but genetics can play a role. Having a family history of Alzheimer’s or frontotemporal dementia may increase risk, but lifestyle factors such as diet, exercise, and cardiovascular health are equally important.

Rare genetic mutations can cause early-onset Alzheimer’s, but these are uncommon. Having a parent or sibling with Alzheimer’s slightly raises risk, but lifestyle choices play a big role in lowering it.

Genetics can increase the risk of Alzheimer’s and other types of dementia, especially the presence of the APOE-e4 gene, but having this gene does not mean someone will definitely develop the disease. Most Alzheimer’s cases are the result of a combination of genetics, age, and lifestyle.

There is no guaranteed way to prevent dementia, but research suggests several strategies can lower risk:

• Staying physically active
• Following a brain-healthy diet (such as the Mediterranean diet)
• Staying socially engaged
• Managing heart health (blood pressure, cholesterol, diabetes)
• Exercising the brain with puzzles, reading, or learning new skills

Currently, there is no cure for dementia. Treatments focus on managing symptoms, slowing progression in some cases, and improving quality of life. Researchers worldwide are working on new therapies, but for now, the best approach is a combination of medical care, lifestyle adjustments, and strong support for both the person living with dementia and their caregivers.