Alzheimer’s Disease: Causes, Symptoms, Diagnosis, and Management

What is Alzheimer’s disease?

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and one of the most common cause of dementia all over the world. It primarily affects memory, thinking, behavior, and the ability to perform daily activities. The disease gradually worsens over time, leading to severe cognitive decline and dependence on caregivers.

Introduction

First described by Dr. Alois Alzheimer in 1906, Alzheimer’s disease is characterized by abnormal protein deposits in the brain—amyloid plaques and neurofibrillary tangles (tau protein). These changes damage neurons, disrupt communication between brain cells, and eventually lead to brain shrinkage.

It usually affects people above 65 years, but early-onset Alzheimer’s can occur before age 60.

Causes and Risk Factors

The exact cause is not fully understood, but several factors contribute:

1. Age

The biggest risk factor. Risk doubles every 5 years after age 65.

2. Genetics

Family history increases risk.

Certain genes like APOE-ε4 are associated with higher risk.

3. Abnormal Proteins

Amyloid plaques

Tau tangles

4. Lifestyle Factors

• Sedentary lifestyle
• Poor diet
• Smoking
• Excessive alcohol
• Lack of mental and social activity

5. Medical Conditions

• Hypertension
• Diabetes
• Obesity
• High cholesterol
• Previoushead injury

Symptoms

Alzheimer’s is gradual. Symptoms are typically divided into early, moderate, and late stages.

Early Stage

• Mild forgetfulness (recent events, names)
• Misplacing items
• Difficulty planning or solving problems
• Trouble finding words
• Mood changes (irritability, anxiety)

Middle/Moderate Stage

• Increased memory loss
• Confusion about time and place
• Difficulty with daily tasks (cooking, managing money)
• Wandering or getting lost
• Personality changes
• Sleep disturbances

Late Stage

• Inability to communicate
• Difficulty swallowing
• Complete dependence for daily activities
• Loss of bladder and bowel control
• Severe weight loss

Diagnosis

Diagnosis is clinical and involves:

1. Medical History & Cognitive Tests

Mini-Mental State Examination (MMSE)

Montreal Cognitive Assessment (MoCA)

2. Laboratory Tests

Blood tests to rule out other causes (thyroid, vitamin B12 deficiency)

3. Brain Imaging

MRI or CT scan

PET scan to detect amyloid or tau pathology (in special centres)

4. Neuropsychological Evaluation

Detailed assessment of memory and thinking skills

There is no single definitive test except a brain biopsy, which is not used in routine diagnosis.

Treatment and Management

There is no cure, but treatment can slow progression and improve quality of life.

Medications

1. Cholinesterase inhibitors:

Donepezil

Rivastigmine and

Galantamine

Help improve memory and cognition.

2. NMDA receptor antagonist:

Memantine

Used in moderate to severe stages.

3. Newer monoclonal antibodies (available in some countries)

Lecanemab

Aducanumab

These target amyloid proteins.

Non-Pharmacological Management

• Cognitive stimulation therapy
• Regular exercise
• Social engagement
• Healthy diet (Mediterranean diet)
• Sleep hygiene
• Maintaining routine and structured activities
• Supportive Care
• Caregiver education
• Safety modifications at home
• Behavioral management
• Advanced care planning

Prevention and Lifestyle Measures

While the disease cannot always be prevented, certain habits lower risk:

• Regular physical activity
• Brain exercises (puzzles, reading, learning new skills)
• Balanced diet rich in fruits, vegetables, whole grains
• Social interaction
• Good control of diabetes, hypertension, and cholesterol
• Avoiding smoking and excessive alcohol

Conclusion

Alzheimer’s disease is a major global health challenge causing long-term disability and emotional burden. Early detection, appropriate management, supportive care, and healthy lifestyle choices can significantly improve the life of both patients and caregivers.