Alzheimer Disease: Life-Limiting, Life-Changing, or Both?

Zaldy S. Tan, MD


August 26, 2015

Editorial Collaboration

Medscape &


What is the life expectancy of a person diagnosed with Alzheimer disease?

Response from Zaldy S. Tan, MD
Associate Professor, Department of Medicine, Division of Geriatrics, University of California Los Angeles; Medical Director, UCLA Alzheimer's and Dementia Care Program, Ronald Reagan UCLA Medical Center, Los Angeles, California

Alzheimer dementia is a neurodegenerative disease characterized by progressive impairments in cognitive functions and the loss of functional independence. While there are several modestly effective symptomatic treatments for Alzheimer and other forms of dementia, a disease-modifying treatment has yet to be identified. Dementia is one of the leading causes of death in the United States,[1] but it may not be recognized by families and healthcare workers as a life-limiting illness.

The median life expectancy for patients diagnosed in their 60s and early 70s is 7-10 years but is only about 3 years or less for those diagnosed in their 90s.[2] These estimates vary in other studies, but shortened life expectancy with dementia was a consistent observation, especially for persons with advanced disease. A study of persons 65 and older with advanced dementia who were admitted to a nursing home showed that only 1% were perceived to have a life expectancy of less than 6 months, yet 71% died within 6 months of admission date; of those who died, only 55% had a do-not-resuscitate (DNR) order.[3]

At the severe or late stage of dementia, the patient will typically be dependent on others for all instrumental activities of daily living and most activities of daily living, including dressing, feeding, toileting, and transferring. It is also in this stage that swallowing difficulty, malnutrition, and infections may appear. In a study[4] of nursing home residents with advanced dementia, the probability of an eating problem was 85.8%, febrile episode 52.6%, and pneumonia 41.1%. Over a period of 18 months, 54.8% died and several distressing symptoms were observed, including dyspnea (46%), pain (39%), pressure ulcers (39%), agitation (54%), and aspiration (41%). These symptoms present management dilemmas about aggressiveness of care, including whether hospitalization is appropriate.

Healthcare practitioners are in a good position to guide persons with dementia and/or their proxies with advance care planning[5] by taking three steps.[6]

  • First, clarify the clinical situation by describing the expected disease trajectory, clinical complications, and the role of surrogate decision-makers (ie, to choose treatment options consistent with advance directives previously expressed by the person with dementia, or in the absence of such directive, to exercise substituted judgment based on what the person would have wanted).

  • Second, establish the preferred level or goal of care based on the perceived preferences of the person with dementia (eg, promote comfort, pursue all available medical interventions or conservative treatment with the goal of returning to baseline status).

  • Finally, treatment options should be aligned with the goal of care, with the healthcare practitioner describing available interventions for specific clinical problems, going through the advantages and disadvantages of each option, and respecting the patient's and/or the proxy's choices.

In summary, Alzheimer disease and other forms of dementia are life-limiting diseases with complications in their late stages that may cause distress and management dilemmas. Advance care planning can help guide clinical treatment decisions that are consistent with the goal of care of the person with dementia.

Developed in association with the UCLA Alzheimer's and Dementia Care Program


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