Understanding Alzheimer’s Disease: Symptoms, Stages, Causes, Diagnosis, and Prevention

Alzheimer’s disease is the most common neurodegenerative condition affecting seniors worldwide. It gradually impairs brain function, leading to memory loss, cognitive decline, and loss of independence. As populations age, understanding Alzheimer’s is more important than ever—for caregivers, loved ones, and those seeking early intervention. In this comprehensive guide, we’ll explore the stages, causes, symptoms, treatments, and prevention strategies associated with Alzheimer’s disease.

Understanding Alzheimer’s Disease: Symptoms, Stages, Causes, Diagnosis, and Prevention

What Is Alzheimer’s Disease?

Alzheimer’s disease is a progressive neurodegenerative disorder that leads to the deterioration of neurons in the brain. This damage disrupts communication between brain cells and causes a steady decline in cognitive functions such as memory, language, reasoning, and spatial awareness.

In France alone, nearly 900,000 people are affected, primarily those over the age of 65. While rare hereditary forms of the disease do exist, most cases are linked to aging. The loss of neurons leads to memory lapses, confusion, difficulty recognizing familiar people and places, and an overall decline in autonomy.

What Are the 3 Stages of Alzheimer’s Disease?

The progression of Alzheimer’s disease varies from person to person, but it generally follows three main stages. Doctors use the Mini-Mental State Examination (MMSE) to assess the cognitive state of patients and determine the stage of the disease.

1. Asymptomatic Stage

No clinical symptoms are present yet, but biological markers indicate early brain changes consistent with Alzheimer’s. This stage allows for potential early detection through advanced testing.

2. Prodromal Stage

Mild symptoms emerge, such as short-term memory loss, word-finding difficulties, and slight spatial disorientation. Individuals are usually aware of these issues.

3. Dementia Stage

Cognitive and functional abilities deteriorate to the point where daily living is significantly impacted. This stage is often divided into three sub-stages:

• Mild Dementia: Frequent memory loss, word-finding difficulties, and confusion in time and space.

• Moderate Dementia: Worsening cognitive issues requiring assistance with daily tasks.

• Severe Dementia: Complete loss of independence, with patients needing help to eat, bathe, or dress.

What Causes Alzheimer’s Disease?

Though the exact causes remain unclear, two proteins play a critical role:

• Tau protein, which forms twisted tangles inside neurons

• Beta-amyloid peptide, which builds up into plaques between brain cells

These proteins become abnormally active, leading to the death of brain cells.

Risk Factors Include:

• Age: Less than 1% of cases occur before age 65.

• Genetics: Mutations in the APP, PSEN1, or PSEN2 genes cause rare hereditary forms.

• Environmental and lifestyle factors: Air pollution, smoking, alcohol use, obesity, diabetes, hypertension, depression, low education, social isolation, chronic sleep deprivation, and use of certain medications like benzodiazepines.

Common Signs and Symptoms of Alzheimer’s

Alzheimer’s affects multiple brain functions:

• Memory loss

• Language difficulties (aphasia)

• Impaired judgment and reasoning

• Confusion about time and place

• Difficulty performing daily tasks

• Mood changes (e.g., irritability, depression)

• Loss of recognition of familiar faces or objects (agnosia)

As the disease progresses, individuals become increasingly dependent on others for basic activities.

How Is Alzheimer’s Diagnosed?

Diagnosis involves:

• Cognitive testing, especially the MMSE

• Brain imaging, such as MRI scans, to detect atrophied areas

• Lumbar puncture, to check for abnormal levels of tau and beta-amyloid proteins

• PET scans, using glucose tracers to evaluate brain activity

These tools help confirm the presence and stage of the disease.

What Are the Treatments for Alzheimer’s Disease?

There is no cure, but multidisciplinary approaches help slow progression and preserve autonomy.

Non-Drug Treatments:

• Speech therapy for language impairments

• Physical therapy and occupational therapy for motor function

• Cognitive stimulation and tailored physical activity

Drug Treatments:

• Cholinesterase inhibitors (e.g., donepezil, rivastigmine)

• Memantine, for moderate to severe Alzheimer’s

Research is ongoing in the field of immunotherapy to halt the disease’s progression at the molecular level.

How Can You Prevent Alzheimer’s?

Preventive strategies mainly target cardiovascular health, which is closely linked to brain health.

Tips include:

• Avoid smoking and alcohol

• Eat a balanced, Mediterranean-style diet

• Exercise regularly

• Stay mentally active (reading, memory games)

• Maintain strong social ties

Frequently Asked Questions (FAQs)

What are the early symptoms of Alzheimer’s?

• Memory loss

• Word-finding difficulty

• Confusion in space and time

• Trouble completing daily tasks

• Mood swings and irritability

What is the “5-word test” for Alzheimer’s?

The Dubois 5-word test assesses verbal episodic memory. Patients are given five unrelated words (e.g., "Frame," "Guitar," "Raspberry," "Medallion," "Desk") to recall immediately and after a delay. It helps screen for early cognitive impairment but is not a standalone diagnostic tool.

Is Alzheimer’s hereditary?

Only about 1% of cases are genetic, typically associated with early onset. Most cases are sporadic, with risk increasing due to age and environmental influences.

What is the life expectancy after an Alzheimer’s diagnosis?

On average, life expectancy ranges from 8 to 12 years post-diagnosis, though some individuals may live longer depending on overall health and disease progression.

How does someone with Alzheimer’s feel?

Patients may experience confusion, anxiety, frustration, and depression. They often lose interest in daily activities and may wander or show signs of aggression due to disorientation.

Medical Sources

• Alzheimer’s Association: www.alz.org

• World Health Organization – Dementia Factsheet: www.who.int/news-room/fact-sheets/detail/dementia

• National Institute on Aging: www.nia.nih.gov

• Inserm – French National Institute of Health and Medical Research: www.inserm.fr

• Brain Institute (ICM) – Paris: www.icm-institute.org