Symptoms of Alzheimer’s disease

Many of the symptoms of Alzheimer’s disease are similar to those of other conditions.

The symptoms of Alzheimer’s disease progress slowly over several years. However, the rate at which they progress will differ for each individual.

No two cases of Alzheimer’s disease are ever the same because different people react in different ways to the condition. However, generally, there are three stages to the condition:

• mild
• moderate
• severe

These stages are described below.

Mild Alzheimer’s disease

Common symptoms of mild Alzheimer’s disease include:

• forgetfulness 
• mood swings
• speech problems

These symptoms are a result of a gradual loss of brain function. The first section of the brain to start deteriorating is often the part that controls the memory and speech functions.

Moderate Alzheimer’s disease

As Alzheimer’s disease develops into the moderate stage, it can also cause:

• disorientation
• difficulty performing spatial tasks (such as judging distances or finding your way around)
• problems with eyesight which could lead to poor vision, or in some cases, hallucinations (where you hear or see things that are not there)
• delusions – believing things that are untrue
• obsessive or repetitive behaviour
• a belief that you have done or experienced something that never happened
• disturbed sleep
• incontinence – where you unintentionally pass urine (urinary incontinence) or stools (faecal or bowel incontinence)

During the moderate stage, you may have difficulty remembering very recent things. Problems with language and speech could also start to develop at this stage. This can make you feel frustrated and depressed, leading to mood swings.

Severe Alzheimer’s disease

Someone with severe Alzheimer’s disease may seem very disorientated and is likely to experience hallucinations and delusions. They may think that they can smell, see or hear things that are not there, or believe that someone has stolen from them or attacked them when they have not. This can be distressing for friends and family, as well as for the person with Alzheimer’s disease.

The hallucinations and delusions are often worse at night, and the person with Alzheimer’s disease may start to become violent, demanding, and suspicious of those around them.

As Alzheimer’s disease becomes severe, it can also cause a number of other symptoms such as:

• dysphagia (difficulty swallowing)
• difficulty changing position or moving from place to place without assistance
• weight loss or a loss of appetite
• increased vulnerability to infection
• complete loss of short-term and long-term memory

It is important to note that infections or medication can sometimes be responsible for an increase in symptoms of disorientation or disturbed behaviour. People with any stage of Alzheimer’s disease with symptoms that rapidly increase should be investigated to rule out these causes.

During the severe stage of Alzheimer’s disease, people often start to neglect their personal hygiene. It is at this stage that most people with the condition will need to have full-time care because they will be able to do very little on their own.

Read more information about how Alzheimer’s disease is treated.

Life expectancy

Alzheimer’s disease affects a person’s ability to look after themselves when they are unwell, so another health condition can develop rapidly if left untreated. A person with Alzheimer’s may also be unable to tell someone if they feel unwell or uncomfortable.

Alzheimer’s disease can shorten life-expectancy. This is often caused by those affected developing another condition, such as pneumonia (inflammation of the lungs), as a result of having Alzheimer’s disease. In many cases, Alzheimer’s disease may not be the actual cause of death, but it can be a contributing factor.