Prognosis for Alzheimer’s disease

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Alzheimer’s is a neurodegenerative disease and therefore the symptoms progressively worsen, gradually leading to a greater degree of dependence.

The disease progresses through different stages:

  • Mild cognitive impairment. Throughout this stage the patient suffers memory problems but can maintain their independence and does not need help from others.
  • Dementia. This is when the patient now finds it hard to carry out activities alone. It could be mild dementia if they only have problems with complicated tasks or severe dementia if they can no longer perform any tasks and have lost the capacity to speak and walk.

On average, each stage lasts for 2-3 years, but some people may remain in the early stages for several years while others may experience a much quicker evolution. People who develop Alzheimer’s live for an average of between 8 and 10 years after the diagnosis; however, some may live with the disease for up to 20 years depending on different factors.

Acute complications

The potential complications associated with Alzheimer’s disease depend on the patient’s stage of evolution.

Older person talking angrily to a young person

Altered behaviour. Patients with Alzheimer’s, especially in moderate or moderately severe stages, can present marked behavioural changes in the form of irritability, aggressiveness or confusion, which may be accompanied by delusions and/or hallucinations. Although these symptoms tend to develop progressively, they can sometimes appear suddenly in a matter of hours or days. These episodes are often caused by changes in the patient’s routine or because of a medical problem, even though it may be mild and sometimes hard to identify.

Old person with a respiratory infection

Respiratory or urinary infections. Respiratory infections and urinary incontinence are frequently observed in advanced stages of the disease. Patients may also find it hard to swallow food correctly.

Chronic complications

Alzheimer’s is a chronic and progressive disease. The possible chronic complications associated with the disease vary according to the patient’s stage of evolution.

Two faces with different moods

In early stages, patients often present mood disorders which could be part of the actual disease or because they are worried about cognitive problems they have noticed or the diagnosis itself, especially if this is made early on.

Older person talking angrily to a young person

In moderate and moderately severe stages, the most significant chronic complication is the appearance of altered behaviours, such as irritability, confusion, aggressiveness (usually verbal), false memories or delusions. These symptoms frequently fluctuate and predominantly arise in the evening (“sundowning” effect). Although these symptoms are very common throughout the course of the disease, in most patients they do not tend to be disruptive or are only temporary.

Recurring dreams

An altered sleep pattern is also typical in moderate and moderately severe stages. Patients may go to bed earlier because they wake up earlier or, alternatively, they cannot sleep and get up several times during the night.

Old person in a bed without legs sensitivity

In severe stages, the main complication is a loss of mobility and its associated problems.

However, Alzheimer’s disease not only affects the patient, but it also has a direct and significant impact on the person or people charged with their care. In this respect, another chronic complication of the disease is caregiver stress syndrome, which is a decline in the mental and/or physical health of the person who looks after the Alzheimer’s patient.

Substantiated information by:

Neus Falgas Martínez
Raquel Sanchez del Valle Díaz
Soledad Barreiro Gigan

Published: 9 April 2018
Updated: 9 April 2018

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.


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