Challenging Behaviors in Alzheimer's Disease

James M. Ellison, MD, MPH

Swank Center for Memory Care and Geriatric Consultation, ChristianaCare

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Bearded senior man embracing and consoling sad senior wife while standing in public park during sunset.

This article is part one of a three-part series and provides an overview of challenging behaviors associated with Alzheimer’s disease, including agitation, sleep disturbances, inappropriate sexual behavior, and apathy.

In 1901, a young German psychiatrist named Alois Alzheimer evaluated his new patient, a 51-year-old woman named Auguste Deter. Ms. Deter, whom we now know as Auguste D., was hospitalized in Frankfurt to manage the debilitating symptoms of her brain disease. Today, we know that she had developed the condition that another psychiatrist, Emil Kraepelin, would later name after Dr. Alzheimer. We also know, thanks to historical research that has located Alzheimer’s original case notes, that Ms. Deter’s disease affected not only her memory but also her behavior. Alzheimer described his patient as pathologically jealous, unable to carry out her homemaking duties, troubled by auditory hallucinations, and fearful of persecution by her neighbors. The challenges presented by Ms. Deter’s non-cognitive behavioral symptoms (NCBS) and memory difficulties resulted in institutional care until her death some five years later.

This article provides an overview of these challenging behaviors, with more specific comments about treatment in two subsequent articles addressing agitation and other challenging behaviors associated with dementia:

Cognitive Impairment

Beginning with the early definition of dementia, and not remedied in the more recent definition of major neurocognitive disorder, clinicians have focused on diagnosing cognitive impairment but have paid relatively less attention to accompanying disturbances of mood, activity, and mental content. The major neurocognitive disorders are diagnosed when clinicians observe a patient to have acquired an impairment in cognitive abilities such as memory, executive function, language, complex attention, visuospatial function, and social cognition. The change in capacity must not be the result of a temporary medical disturbance that is causing confusion and must be sufficient to interfere with daily functioning to such a degree that independence is compromised.

Behavioral Changes

For many clinicians and caregivers, this focus seems misplaced because it is, in fact, the challenging behaviors of cognitively impaired people that create most of the distress, difficulty, and even danger involved in their care. Many caregivers seek help from healthcare providers to assist them in managing the challenges posed by the behaviors that accompany cognitive decline. Apathy or depression, for example, can further deplete a patient’s already limited quality of life. Agitation and aggression can endanger both patients and caregivers. Inappropriate sexual behaviors, which can frighten or harm others, can make it difficult for a cognitively impaired person to get along with others at home or in long-term care settings. Sleep disturbances can tax the endurance of caregivers beyond tolerance. Yet there are no widely standardized treatment approaches for addressing these behaviors and no FDA-indicated medications for treatment of them.

Early Signs and Symptoms

Behavioral symptoms not only accompany cognitive impairment in Alzheimer’s disease but, in some cases, even precede them. Social withdrawal, depression, anxiety, suicidal ideation, and mood changes have been shown to precede the onset of severe cognitive changes in Alzheimer’s by as much as several years. Over the course of the illness, more than 90% of Alzheimer’s patients will demonstrate challenging behavioral changes.

Common Behavioral Changes


The most common of these changes is apathy, a loss of motivation and initiative. The apathetic person appears emotionally indifferent or even depressed. Apathy shares with depression the features of low energy and interest, poor self-care, and diminished activity. Apathy differs importantly from depression in that sad mood, tearfulness, self-deprecating feelings, and suicidal thoughts or behaviors are less often present in apathy than in depression. Though less frequent than apathy, depression often complicates the course of a major neurocognitive impairment. Behavioral and medication treatments for apathy and depression, along with treatments for other challenging behaviors, will be addressed in a subsequent article.


Agitation has been defined by Dr. Cohen-Mansfield, a psychologist who has studied it thoroughly, as “inappropriate verbal, vocal or motor activity that is not judged by an outside observer to be an obvious outcome of the needs or confusion of the individual.” Aggression may accompany agitation, threatening a dangerous situation for frail older adults with Alzheimer’s or for those in their vicinity. In long-term care facilities, some 5% of residents are physically aggressive each year, resulting in thousands of assaults, some of which are lethal.

Inappropriate Sexual Behavior

Sexual behavior that is not appropriate to a person’s circumstances is often an inarticulately expressed request for closeness or comfort. Such inappropriate sexual behavior is a less frequent complication of Alzheimer’s but is regarded as particularly disruptive because of the distress it may cause in others. Inappropriate touching of others or oneself while in public places can make a person with Alzheimer’s unwelcome, among others, including caregivers, long-term care residents, and even children with whom the affected person may interact.

Sleep Disturbances

Sleep disturbances affect more than half of severely demented Alzheimer’s patients. The part of the brain that helps us tell day from night is compromised early in the course of the disease, so sleep problems occur early and represent one of the most difficult issues for caregivers. The Alzheimer’s patient sleeps chaotically, dozing during the day and wandering at night. Changes in the sleep-wake cycle may contribute to the increased confusion, called sundowning, which often occurs in the later afternoons.


As a general principle, each of these challenging behaviors responds fairly well to behavioral and environmental interventions. Medications may provide additional help. The risks and complications of medications, particularly given the frailty and sensitivity of the older adults who may take them, have led to an emphasis on non-medication approaches to management. Both non-medication and medication approaches to agitation and to other challenging behaviors associated with Alzheimer’s will be discussed in later articles in this series.

About the author

Headshot of Dr. James Ellison

James M. Ellison, MD, MPH

Swank Center for Memory Care and Geriatric Consultation, ChristianaCare

James Ellison, MD received his medical degree from UCSF in 1978 and trained in psychiatry at the Massachusetts General Hospital (1979-1982).

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