Dementia has many causes and can take many forms. Some complications may be the result of the underlying illness that is causing the dementia. Others may arise from the dementia itself.

Possible complications of dementia, regardless of its cause, include the following:

  • loss of previous ability to function or care for self
  • loss of previous ability to interact with others
  • reduced lifespan
  • increased infections within the body

As the disease progresses, additional complications may include:

  • forgetting recent events or conversations
  • difficulty performing more than one task at a time
  • difficulty solving problems
  • taking longer to perform more difficult activities
  • language problems, such as trouble finding the names of familiar objects
  • misplacing items
  • getting lost on familiar routes
  • personality changes and loss of social skills
  • losing interest in things previously enjoyed, flat mood
  • difficulty performing tasks that used to be easy, such as balancing a checkbook
  • playing complex games such as bridge
  • learning new information or routines
  • forgetting details about current events
  • forgetting events in your own life history, losing awareness of who you are
  • change in sleep patterns, often waking up at night
  • difficulty reading or writing
  • poor judgment and loss of ability to recognize danger
  • using the wrong word, mispronouncing words, speaking in confusing sentences
  • withdrawing from social contact
  • hallucinations, arguments, striking out, and violent behavior
  • delusions, depression, agitation
  • difficulty doing basic tasks, such as preparing meals, choosing proper clothing, and driving
  • difficulty swallowing both foods and liquids
  • incontinence

The stages of dementia »

Alzheimer’s disease (AD) is the most common form of dementia. Complications of AD may include the following:

  • loss of ability to function or care for self
  • falls and broken bones
  • loss of ability to interact with others
  • malnutrition and dehydration (those with AD may not eat or drink properly)
  • failure of body systems

Those with AD can become easily confused and frustrated. This can lead to harmful or violent behavior toward themselves or others. They may also not eat or drink properly, which can lead to malnutrition and dehydration.

If AD reaches its final stages, the complications include:

  • inability to recognize family members
  • inability to understand language
  • inability to perform the basic activities of daily life, such as eating, dressing, going to the bathroom, and bathing

During the end stages of AD, a number of complications related to immobility may occur. These might include:

  • bedsores
  • muscle contractures (loss of ability to move joints because of loss of muscle function)
  • infection (particularly urinary tract infections and pneumonia)

Complications of Alzheimer’s disease (AD) »

People with dementia will eventually need to be cared for by family or a professional caregiver. According to the Family Caregiver Alliance, dealing with Alzheimer’s can sometimes be counterintuitive.

10 things to add to your caregiver toolkit »

Remember, caretakers need to care for themselves to effectively care for others. There are many resources available for caregivers to provide support and guidance. Caregiver support can be found at:

The fight to become my parents’ caregiver »

Mild cognitive impairment doesn’t always lead to dementia. Depending on the cause, some dementias might be reversible. However, most dementia is progressive. This means it gets worse over time. Treatments focus on relieving the symptoms and slowing the progression. Each case is different. Dementia may progress quickly or slowly. This often depends on the cause. In general, dementia shortens life expectancy. This varies with the person and the cause.