Why Do People Die from Alzheimer's Disease?


Q: If Alzheimer’s is a disease of the memory, how do people die from it?

A: Alzheimer's disease (AD) is very complex and always fatal. It manifests initially with marked memory failure, but as it progresses, it also has an effect on higher brain functions. In the later stages of the disease, balance and coordination as well as autonomic functions like heart rate, breathing, digestion and sleep cycles are severely affected.

When the clinical picture of the disease is fully developed, a patient will be unable to perform the tasks that keep our bodies alive and functioning. Neurological damage causes the patient to lose the ability to coordinate even simple movements. Eventually, they are unable to walk, communicate, maintain control of their bladder and bowels, feed themselves, chew, and swallow food without significant assistance and careful supervision. The later stages can be both emotionally and physically taxing not only for patients themselves, but also for their family caregivers. At this point, if the subject has not already been discussed, family members may wish to consider hospice care for their loved one.

This lack of self-awareness and self-care, prolonged confinement to a bed, feeding failure and inability to receive proper nutrition and hydration are all factors in the development of other life-threatening diseases. While brain damage associated with AD is the driving force behind the patient's decline and incapacitation, these secondary illnesses and conditions are actually responsible for causing the patient's death and are commonly cited as such on death certificates.

The most prevalent cause is a secondary infection, commonly pneumonia. Bacterial infections could be easily remedied with a course of antibiotics in healthy individuals. However, advanced AD patients are usually too frail and immunocompromised to fight, even with the assistance of these drugs. Infections often return after treatment, and many patients or their family members make the decision to forgo aggressive treatment options and/or resuscitation efforts that may cause pain and discomfort for only a short-term benefit.

All of the below conditions can cause or contribute to multiple organ failure and death.

  • Heart attack
  • Dehydration and malnutrition, whether through a voluntary stopping of eating and drinking (VSED) health care directive or the natural dying process
  • Injuries and fractures caused by falls
  • Thromboembolisms
  • Pressure ulcers (bedsores)
  • Stroke
  • Kidney failure
  • Lung infections like aspiration pneumonia due to inhalation of food particles
  • Sepsis (if infections like UTIs and pneumonia spread)

Unfortunately, deaths with a primary cause of Alzheimer's disease and other forms of dementia are seriously underreported. This is especially true since AD can go unnoticed as it progresses slowly over the course of many years. Furthermore, a significant number of patients never receive an official neurological diagnosis.

Dr. Maurizio Grimaldi

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Grimaldi is the Leader of the Neuropharmacology and Neuroscience Laboratory at Southern Research Institute in Alabama and specialized in clinical pharmacology. He is a co-investigator in the NIH-NINDS Drug Screening for Neurodegenerative Diseases and Stroke.

Southern Research Institute

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I reached this site after googling for information. Someone posed the question to me yesterday, "How does a person actually "die" from Alzheimer's disease?" ... My father passed away 3 weeks ago today (1/1/2010) at the age of 82, from end stage Alzheimer's. He had been healthy all of his life until he had a stroke about 5 yrs ago. This did not affect him physically, but it did affect him mentally. Over the next few years he was diagnosed with Alzheimer's. He progressed very slowly and remained very active in the yard and house until September 28, 2009. On that day, he wandered on their property behind their home (a couple of acres), fell into a deep hole, and was "missing" for approximately 5 hours. We finally found him with the help of neighbors, EMS, and the police. This traumatic event was the beginning of the end for him. Between that day and December 11, 2009, he only stepped outside twice, for extremely short walks with assistance. My mother (78) and I (51) took care of him at home as his Alzheimer's progressed like lightning through his body, taking full control. In mid-October we brought in Hospice assistance, which was so helpful. Those people are life-savers. They did for Dad, but they also educated us, teaching me many things I could do to help Dad be more comfortable, helping me be a better caregiver. I had a job where I worked from home, however, they were not understanding of my plight in caring for Dad, so I quit my job in order to give all my time to caring for Daddy, feeling in my heart that he would not be with us long. Alzheimer's is the most cruel disease and it affects everyone. I watched it rapidly overtake my father's body and mind in the last months of his life. Alzheimer's is not just a "memory" disease - it just often begins that way. Although I "lived" the answer of "how one dies from Alzheimer's," I was struggling for the words to verbalize that to others. I am trying now to be able to do that. People need to be more aware and informed about Alzheimer's and I intend to do whatever I can to help in that regard so that my father will not have suffered and died in vain. ... I was very glad to see this site. ... Peace to all. ... Diane S.
My mother had her 90th birthday on May 6th. She's had Alzheimer's for about the last 10 years. Until October, 2012, my father was able to care for her at home, but after the second time she fell and could not get up, he arranged for her to move to a nursing home.
This turned out to be very good for both of them. She had the care she needed, and he could spend 6+ hours a day with her, as well as socializing with other residents and staff.
He died March 2, unexpectedly, from pneumonia complications. Mom is still at the nursing home, 5 hours from me and 10 hours from my sister. Her body is too strong to fail, but her mind is gone. She cannot walk or talk, but she still eats all her meals. She signed a do not resuscitate order back when she could, but her body still keeps going.
My sister and I are trying to decide what to do: to leave her there, where she has gotten good care (albeit with my father present to notice and appreciate) or to move her to my town where I can visit daily. Cost is a factor - the nursing homes will cost about the same, but the move could cost $1000 we don't have. Plus, moving her would take her out of familiar surroundings - even though those familiar surroundings are a nursing home, a place she never wanted to be in the first place.
I know she is ready to go, since Dad is no longer there. I don't want to leave her alone, but I can't afford to drive there and stay in a hotel more than once a month.
As my aunt reminded me recently, there is no correct decision here.
I lost my mother, the one who knew all the family stories, wrote wonderful letters to everyone including the local newspapers, and kept me on my toes, about 6 years ago. I feel I lose her again everytime I see her, and that I'm letting her down every time l have to leave her.
My sister thinks she's in the final stages and doesn't know what's going on around her, but the last time I saw her, when I told her it was time for me to leave, she reached for my hand and looked at me so longingly, like there was something she wanted but she couldn't tell me what.
I told her "Mom, I know you're ready to go, but there's nothing I can do. I'd suffocate you with a pillow if I could... "
As others have written, thanks for reading this. I appreciate the chance to share with others who are dealing with the same loss.
Thanks for your comment. But I refuse to ask someone even grown children to help us. They should want to and the fact they never volunteer shows me they do not want to. I would not feel right leaven my husband of 45 years with someone who really doesn't want to be with him. One son just says the cats in the cradle. He's refering to the song of long ago. The differnce was his dad was out working 2 jobs and going to college to provide for all of us. Its ok, took him with me shopping last night and the only thing he enjoyed was Golden Corral. Went in Victoria Secret to pick up something for our granddaughter and he said well I don't think I need to be in here!!
sometime you laugh sometime you cry but God is still in control.
Hes always with me!!