Why Do They Die? What Causes Death in People with Alzheimer's Disease?

Causes of Death in Alzheimer's Disease
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Question: What are the Causes of Death in People with Alzheimer's Disease?

The Alzheimer's Association notes that Alzheimer's disease is the sixth leading cause of death in the United States. It also points out that out of the top ten causes of death, it's the only one without an effective treatment or cure.

Average life expectancy for people living with Alzheimer's is four to seven years after diagnosis, although some people may live as much as 20 years or more.

But, what actually causes death in people with Alzheimer's disease?


In late stage Alzheimer's disease, people become extremely confused and disoriented. The behavior of someone with late stage Alzheimer's may become more agitated and restless, while other persons experience withdrawal and apathy. Sometimes, people with later stage dementia cry and call out. Eventually, they lose the ability to communicate, and they may not respond at all.

Additionally, people in the late stages are unable to care for themselves, becoming bedbound and completely dependent on others for their activities of daily living. Their ability to be continent of bowel and bladder declines. Their appetite decreases as well, and eventually they lose the ability to swallow, leading to poor nutrition and a high risk of aspiration. Aspiration, where a person's food goes "down the wrong tube" when they swallow it, greatly increases the risk of pneumonia developing because they're not able to fully cough and clear the food out of their esophagus and then it settles into their lungs.


Under these difficult conditions, it's not hard to imagine how vulnerable people with late-stage dementia become to succumbing to infections, pressure sores and pneumonia. One study found that half of all people with dementia admitted to a hospital for pneumonia or a hip fracture died within six months of leaving the hospital.

Another study that examined autopsy reports of people with dementia found the main causes of death were pneumonia, cardiovascular diseases, pulmonary embolism, cachexia, and dehydration.

Other factors that impact the death rate in Alzheimer's disease include advanced age, increased falls and delirium.

Important Steps

An important decision to make prior to a person's decline in later stage Alzheimer's disease is related to advanced medical directives. These directives include designating a healthcare power of attorney and a financial power of attorney, making end of life decisions such as a decision about resuscitation, and conducting research about palliative care and hospice care for someone with dementia.


Javier, Noel S.C., MD, "Palliative Care for the Nursing Home Resident with Dementia", Medicine and Health Rhode Island 93; 12:379-81, December 2010.

-Updated by Esther Heerema, MSW

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