Life Expectancy for Someone With Alzheimer's

Issues That Affect Life Span for Someone With Alzheimer's
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Knowing the life expectancy of someone with Alzheimer's can help your family prepare for the gradually increasing amounts of care giving that eventually will be needed. Someone in the final stages of the disease, for example, requires constant hands-on care. Estimating life expectancy can help you and your family plan ahead for all the practical and financial issues you'll face.

What's the average life expectancy of someone with Alzheimer's?

The general rule of thumb is that a person diagnosed with Alzheimer's can expect to live half as along as a peer who doesn't have the disease. For example, the average 75-year-old in 2007 can expect to live another 12 years. A 75-year-old with Alzheimer's, in contrast, would be expected to live for six more years.

It's hard to gauge an individual's life expectancy based solely on the stage of Alzheimer's. That's partly because the length of each stage (early/middle/late) can vary greatly from individual to individual. Some people live 15 or more years after diagnosis, including many years with relatively mild impairment, while others decline rapidly and die within a few years of being diagnosed. In general, someone who's just beginning to show symptoms can be expected to live longer than someone of the same age with end-stage Alzheimer's.

What Influences Alzheimer's Longevity?

Scientists have a growing understanding of which Alzheimer's patients are more likely to outlive their peers with the disease. In 2004, a University of Washington study funded by the National Institute on Aging (a branch of the National Institutes of Health) identified several factors that influence life expectancy:

  • Gender. Women in the study tended to live longer than men -- an average of six years after diagnosis, compared with four years for men.
  • Age at diagnosis. People diagnosed with Alzheimer's in their 70s had longer survival times than those older than 85. The male-female difference shrank among those who were older when they first developed the disease. Newly diagnosed 85-year-old women in the study had a median life expectancy of 3.9 years, compared with 6 years for unaffected women of the same age. A man diagnosed with Alzheimer's at 85 had a life expectancy of 3.3 years in the study, compared with 4.7 years for a man of that age without the disease.
  • Severity of symptoms. The more significant the impairment at the time of diagnosis, the shorter the probable number of years left. People over 85 who wander or have trouble walking, for example, are among those with the poorest survival rates.

Also showing diminished survival rates were study subjects who scored the worst on a commonly used memory and cognition (thinking skills) test, the Mini-Mental State Exam (MMSE).This test asks subjects to do a series of simple tasks, including answering questions about the date and place, remembering three objects, and counting backward by increments. An MMSE score refers to the number of correct answers given out of a total of 30. A five-point drop in score over the course of a year was linked to decreased survival rates among patients in the study.

However, simply scoring poorly doesn't mean a person doesn't have long to live. Sometimes a poor MMSE score is the first indication of cognitive trouble, which may indicate the very start of Alzheimer's and therefore a longer life expectancy than predicted for someone who's had memory problems for years.

Note: There are multiple factors that can influence an MMSE score. The test is not an Alzheimer's diagnostic test -- in fact, no such test exists.

  • Other health problems. Survival was also poorest among those aged 85 and older who had histories of diabetes, congestive heart failure, or a past heart attack.

What often happens in people with Alzheimer's disease is that their general health suffers when, in the late stages, they forget or find it difficult to eat, don't sleep properly, lose motor skills, and develop bedsores. This sets the stage for infection, such as pneumonia, or the worsening of other chronic ailments. It's those factors, not the Alzheimer's disease itself, that ultimately result in most deaths.

Bear in mind that the facts above represent group averages. Your parent, of course, is an individual with a unique health history. And Alzheimer's is a disease whose pace can vary widely from person to person. Still, having even a rough sense of what to expect can provide a glimmer of useful light at a difficult time.

Paula Spencer Scott

Paula Spencer Scott is the author of Surviving Alzheimer's: Practical Tips and Soul-Saving Wisdom for Caregivers and much of the Alzheimer's and caregiving content on Caring. See full bio

about 2 months, said...

My Mother was diagnosed with Vascular dementia in 2014 and myeloma in 2015 she has got very thin, sometimes looks yellow, but recently her dementia has dramatically got worse. She is nearly 96, is not interested in reading or watching TV and does not have much of an appetite. She cannot walk hardly at all and if she tries on her own she can fall over. She is in a home now. How long do you think she has left, she still knows her own children but has difficulty with anyone else.

over 1 year, said...

My mother's brain was injured in car accident back in 1988 and she actually never became quite normal again. She was 59 years at that time. From 1995 onward her mental condition started to get worse again with typical symptoms of mild alzheimer. In 2006 she could not live at home anymore but was taken to a nursing house. From that time onward her condition has deteriorated continuosly. In the beginning she used to knit socks for my daughters, read books etc... but after a couple of years she could only enjoy herself by looking old family photos. Ability to speak disappeared gradually and then she could only eat when fed by nurses. At the moment she is all the time in bed and most of the time sleeping. She does not recognize anybody and obviously don't know where she is and what is the situation. Her body has become slim and hair is getting lost totally. I am wondering why the nurses always have told me that nothing has changed in her condition when I have been calling the nursing home once in every few weeks. I have the possibility to visit her only a couple of times a year and I have been able to see dramatic deteriorating every time. Compared with the time she used to chat, knit and read books she is now like a zombi. Why have the nurses not told me the truth. The message has always been "no particular changes in her condition". I am wondering how long she still has to suffer. She is now 87 years old.

about 2 years, said...

Hi, Irisized. There is really no way for us to answer your question, since your husband is apparently a very complex case. The symptoms you describe could be from severe Alzheimer's, from improperly controlled diabetes, and/or from a complication such as gastroparesis. I would suggest that you try putting your husband on a gastroparesis diet and see whether that helps improve his discomfort and weight loss. I would not put him through a test -- I'd just try the diet and see if it helps. (That's what I did with my husband, and he was able to eat again and put weight back on, and clearly felt much better.) Google "type 1 diabetic gastroparesis". I'd also suggest that you discuss his diabetes treatment with his specialist. I'd also suggest that you research local hospice providers and ask to have your husband evaluated under "debility unspecified" (aka "debility NOS", or "failure to thrive") coupled with the Alzheimer's and diabetes diagnoses (and perhaps others.) If he qualifies, hospice can be very helpful to him, and to you.

about 2 years, said...

my husband was diagnosed with severe brain atrophy in 2012 they felt was from high and low blood sugars from type 1 diabetes...then in 2014 they thought lewy body dementia, then a pet scan in the summer of 2014 show moderate alzheimers.... he is rapidly declining and has lost over 16 lbs in less than 6 months. He sleeps a lot and cannot dress, I have to shave him and when he pees, it never makes it in the toilet....he looks like swallowing bothers him.... I am sole caregiver and will care for him at home... but what would be the average life expentancy with someone with what I feel is end stage 6 and type 1 diabetes

almost 3 years, said...

My wife has been diagnosed with first stage or mild Altzheimers, and all articles on the matter are very helpful for me. Thanks for the articles.

about 3 years, said...

My father in law has been given 6 months to live according to his Doctors! He has been diagnosed with advanced staged dementia and Alzheimer's. I know he has these but feel that they are writing him off!! He has been going down hill for the last year! Can this really happen this fast? I need help to make his children understand what's going on

about 3 years, said...

Many people think it is only losing memory. I told someone that told me that that it breaks down the whole person and destroys the person. There is no light at the end of the tunnel. All we can do is watch in horror as our loved one is slowly but surely picked apart until only the shell is left. By that time, the tears have already been used up so death is a relief.

over 3 years, said...

Oh, Diane ... (((((hugs))))) I don't believe there is any simple answer to your question. Any sort of infection can exacerbate Alzheimer's symptoms and/or cause new ones, including incontinence, difficulty communicating, and extreme fatigue. So ... you cannot tell what stage her Alzheimer's is from what is happening right now. Once the infection has cleared up, the loved one often will improve again, and may even revert to "baseline", i.e., to the stage she was in before the infection set in. However, the big question to my mind is whether the doctors will be able to bring the infections under control. Your mother has so many very serious problems, all on top of each other, that they may be weakening her enough to the point she may not survive ... not because of the Alzheimer's itself, but because she is so frail and so sick. Can you ask the doctors, point blank, what her prognosis may be? I know it is sometimes very hard to communicate with healthcare professionals under such circumstances. I would also encourage you to ask that they consider hospice for her. Hospice can help her be more comfortable, and can also help comfort you. They may be better able to discuss the situation with you, and the alternatives for the best care for her.

over 3 years, said...

Mum 80 diagnosed alzheimers 3 yrs, in hospital 6wks, went in with acute cholocystitis, chronic diverticulitis disease. While in she's contracted pneumonia and c difficile still positive after 3 wks, totally urine incontinent and has diahrea, which I think she's bowel incontinent too. Lost all interest in everything she once loved up until 3weeks ago and now sleeps 90%of the time. Voice very quiet, and generally can't be bothered with anyone. Blank staring, and finding it hard to think of words she's trying to say, is this the final stage. Diane

over 3 years, said...

my spouse is near 82, and was diagnosed four years ago. He has less stamina and evenings are the worse. He does nothing much but sit or walk a little. He is getting thinner. I try to make sure he eats well but weight is an issue. I do almost everything around here that does not require lifting. We have been married 34 years. I did not break up his marriage to his first wife. I am his third wife. His children treat me horribly , his sons are into bad things and threaten me as much as they can. We live in the home I own. He is a good man with bad kids. Their mother could not control them when he worked two jobs for them. Our life has been good but I fear his sons. He got so he would not go near them either. If I outlive him (I am 11yrs younger then he) I think they will hurt me or try. Their wives are no better. They have robbed their mother. My husband went to the local law prior to becoming totally unable to talk well and told them what they were doing so they have been warned to leave us alone. Their whole family is afraid of them.

almost 4 years, said...

In October my Mom came to live with me. She lost her husband one year ago. She was in my sisters care. While she was in my house she was quiet but did nothing at all. She kinda just sat and I waited on her. A lodge had a vacancy with home care available (less then I thought). She is there now and they are saying she has dementia. (Could be Alzheimer's or could be related to addictive narcotics that she was put on and carelessly left on).? I began weaning down the dosage of the Ativan. She was dizzy all the time and I was constantly at the hospital with her. She finally fell and I began the reduction of the long term use of Ativan.? She was obsessed about her drugs prior to the addiction and is still obsessed. Not much diff but now has me to blame for her misery. She has times when she seems normal and other times when is obsessive controlling lacks judgement and can he forgetfull. I am finding it difficult to deal with it all. A stiff upper lip is difficult to maintain. Advice??????

almost 4 years, said...

Nothing because nothing in regard to Alzheimer's appears concrete.

about 4 years, said...

Little John: I understand what you said in re to your Mom, my Mom was abusive to me too but realize this woman had big issues. You are not her. Let go of the hurt, kiss each sunrise and realize you were lucky to survive the abuse. I have a niece and sister who are like my Mom. I had always been good to them but they are BP . I woke up one day and said no more abuse from these people. I said a prayer, to bless them and have moved on without them in my life. Find people or professionals to help you get to the real you. You sound like you understand life well. Be kind to people that are kind to you. Love your children and wife. Live so that when you pass people will say "John was a great friend, uncle, etc. Do not base who you are by this very sick lady. I never fit into their sick pot, I worked hard made my way, married a wonderful man. He is ill now but he is my hero.' Find you the real you John, the one you want to be. You can do it. A nurse

over 4 years, said...

My Wife started showing signs at age 79. She is now 86 and inan alzheimers home since I can't take care of her anymore. She seems to be in excellent health other than her memory.