Aggression is not a stage of dementia — rather, it is a symptom. It does not happen to everyone or follow a predictable pattern or timeline.

Aggression is often, but not always, a symptom that occurs in the later stages of Alzheimer’s disease. But different types of dementia have different symptoms, and aggression can appear at any time with any form of dementia.

People experiencing aggression during dementia may be confused. They may not understand what is happening. Alternatively, they may have delusions or hallucinations that cause them to perceive loved ones as threats.

It is important to recognize aggressive behavior as a form of communication indicating that something is wrong and a sign that the person needs additional treatment and support.

Read on to learn more about aggression and dementia.

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Aggression is not limited to a single stage of dementia. People with dementia may behave aggressively at any point in the course of the disease.

The potential timing and type of aggression also depend on the type of dementia a person has. For example, frontotemporal dementia tends to cause behavior and mood changes early in the disease. People with Alzheimer’s disease are more likely to display memory changes first, with personality changes appearing later.

According to a 2020 review, 90% of people living with dementia experience behavioral or psychological symptoms such as aggression, agitation, and depression.

Dementia is a highly unpredictable disease. The progression of the disease and its symptoms vary from person to person and depend on the type of dementia a person has.

As a result, there is no standard for how long a single episode of aggression may last or for how long a person may experience aggression as a symptom during the disease. Not all people with dementia display aggression.

A number of factors may cause or prolong aggression in a person with dementia. This is because aggression can occur for many reasons. Addressing the underlying cause may help shorten an aggressive episode.

Because of the unpredictable nature of dementia, it is impossible to know how long each stage will last. This is especially true in less common forms of dementia, such as frontotemporal dementia.

People with dementia have the same emotions and needs as people without dementia. This means their environment can affect their behavior and emotions, including aggression.

A person with chronically unmet needs may be aggressive most of the time, while a person in a nurturing environment that centers their needs may be less likely to be aggressive.

Aggression in dementia may be primary, which means that dementia itself causes the aggression, or it may be secondary — a reaction to external events.

Primary causes of aggression in dementia include:

  • Brain changes: Dementia changes a person’s ability to think and understand information, which may result in aggression if a person feels confused or threatened.
  • Hallucinations: A person with dementia may experience hallucinations, seeing or hearing things that are not there. This may cause them to behave aggressively out of fear or because they think they are defending loved ones.
  • Delusions: A person with dementia may have false beliefs, such as that a caregiver is poisoning them.

Secondary aggression can happen in circumstances such as:

  • Inability to communicate: Some types of dementia, such as primary progressive aphasia, affect communication first. Additionally, in the later stage of most dementias, communication may be difficult. A person may become aggressive when they cannot express their needs.
  • Fear or anxiety: Dementia undermines a person’s ability to think clearly and to understand the world around them. They may become fearful of caregivers, loud noises, or new experiences.
  • Sensory overload: Some people with dementia become aggressive because they feel overwhelmed by the surrounding world. For example, they might find the sound or temperature of a shower terrifying.
  • Depression: Many people with dementia experience depression. This may lower their threshold for aggression.
  • Personality: People who behaved aggressively before developing dementia may continue to be aggressive or become more aggressive in response to the stress of living with dementia.

Managing aggression depends on identifying the underlying cause. The following methods may be helpful:

  • Medication: Some drugs can ease agitation or help with delusions and hallucinations. A doctor may recommend antipsychotic medication if a person appears to be disconnected from reality.
  • Physical therapy and support: Some people with dementia become aggressive because of painful movement or limited mobility. Physical therapy and adaptive devices may help.
  • Pain management: People who are in pain may become aggressive when they feel desperate or unheard. The right pain management strategies may help.
  • Communication strategies: Caregivers may be able to reduce frustration by changing the way they communicate with a person who has dementia. For example, caregivers can make their instructions simple and clear and avoid giving too much information at once. It is also important to maintain eye contact and give the person time to respond.
  • Easing panic: Strategies to reduce fear and anxiety can help. For example, if a person fears bathing, forcing them to bathe may do more harm than good. Calm voices, familiar settings, and slow movements can help some people.

A dementia care coordinator or an occupational therapist specializing in dementia may be able to make personalized recommendations for easing distress.

A person should seek help from medical professionals if they are finding it hard to care for a person with dementia. This applies if:

  • the person’s condition suddenly worsens
  • new or worsening symptoms develop
  • the person develops aggression that makes them dangerous to themselves or others

It is important to speak with a doctor even if a person does not yet have a formal diagnosis of dementia.

A 2019 study of people with Alzheimer’s disease — just one of many types of dementia — found that people who received a diagnosis earlier tended to live longer with the disease. At age 60, the average overall duration of the disease was 24 years, but by age 80, that figure dropped to 15 years.

Dementia can be scary, especially when a person can no longer express their needs or understand the world around them. Aggression is a common reaction to this uncertainty. It can also be a symptom of the disease itself due to changes in the brain.

While dementia does not yet have a cure, aggression is manageable and often treatable. With support from a doctor or a dementia expert, caregivers can create an environment that eases feelings of aggression, anxiety, and agitation.