As a progressive condition, Alzheimer’s disease symptoms develop gradually and become more severe over time.In many people, symptoms can take as long as ten years to become severe enough to cause concern.

The exact cause of Alzheimer’s disease is not clearly understood, but patients with the condition have been found to have abnormal protein deposits (amyloid plaques) in their brains, along with fibres called tau tangles and a chemical called acetylcholine. These disrupt neuronal messaging in the brain and eventually cause damage to areas of the brain that affects memory and cognitive processing.

Due to the slow, progressive nature of this disease, it often goes unrecognized in the early stages. Dementia and memory problems are often considered a normal part of aging and there is no one test that can diagnosis Alzheimer’s disease. However, an early diagnosis can help people to plan and prepare for the future, so people suspected of having the condition should be supported in seeking medical advice.

The first symptom is usually a minor affect on the memory, with an individual tending to forget about a recent conversation, event or the name of an object or place, for example. Gradually, memory problems worsen and other symptoms start to develop such as confusion, increased aggression or other personality changes. The affected individual may also experience hallucinations and difficulty with language and speech. As the condition worsens, the patient eventually finds it difficult to move around independently and becomes dependent on caregivers in their day-to-day living.

A more detailed description of the various symptoms that may be seen during the different stages of Alzheimer’s progression, is given below.

Early stages

• The main symptom is decline in memory and a person may fail to remember recent conversations or events
• Forgetting the names of objects or places
• Forgetting when they last said something and repeating themselves

Individuals at this stage of disease may also demonstrate poor judgement and decision making and show a lack of interest in things. Mood changes such as increased anxiety or confusion may also occur.

Middle stage

Memory problems become more severe and the patient may even fail to recognise family members or friends. Other symptoms include:

• Obsessive and repetitive behavior
• Delusions
• Speech and language problems
• Disorientation and tendency to forget where they are or why
• Disrupted sleep
• Mood swings and increasing feelings of anxiety and depression
• Poor judgement of distance
• Poor vision
• Hallucination

By this stage, the patient usually requires day-to-day assistance with carrying out tasks such as washing, dressing, eating and using the toilet.

Later stage

Symptoms eventually become severe and can be extremely distressing for both the patient and their family and friends.

Hallucination and delusional thinking may worsen, with the patient becoming aggressive and suspicious of people around them. At this stage, patients often pose a danger to themselves and require full-time care.

Other symptoms include:

• Difficulty swallowing
• Difficult moving around independently
• Weight loss
• Incontinence
• Speech loss
• Significant decline in both short- and long-term memory
• Neglect of personal hygiene

Further Reading

• All Alzheimer's Disease Content
• Alzheimer’s Disease | Definition, Causes, Diagnosis & Treatment
• Alzheimer’s Disease Causes
• Alzheimer’s Disease Diagnosis
• Alzheimer’s Disease Treatments

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.