Skip to Main Content (717) 697-3223

Distinguishing Between Dementia and Delirium – Keystone Elder Law – Mechanicsburg PA


A loved one is experiencing changes in his/her behavior, thinking skills, and/or general emotional state. Family members may initially attribute these changes to the onset of dementia. However, there is a separate and distinct condition, with symptoms similar to dementia, which should be considered in some cases.  This condition is called delirium.

The symptoms that one may see with delirium are numerous. One of the classic signs is a lack of focus.  An individual’s awareness of their environment is reduced and he/she becomes unable to follow a conversation or respond appropriately to questions, easily distracted by unimportant details, or fixated on a certain idea.  Sometimes withdrawal occurs, and the individual demonstrates little or no response to environmental stimuli.  A lack of focus may be accompanied by changes in behavior such as hallucinations, restlessness or agitation, mixing up days and nights, or frequent verbalizations such as moaning or calling out.  The impairment of thinking skills is evidenced by decreased memory (especially short-term); disorientation; speech that is rambling or doesn’t make sense; and changes in reading, writing, and understanding language.  Emotional symptoms may include anxiety, fear, or paranoia; irritability; euphoria; apathy; or rapid and unpredictable mood swings.

All of the above symptoms may sound like dementia, but the key difference in delirium is that these symptoms have a rapid onset, usually within several hours or days. With dementia, the symptoms have a gradual and more subtle onset.  Symptoms of delirium may also vary widely during the course of a day, and are usually more evident at night as darkness makes the environment even more difficult to interpret. Symptoms of dementia will not fluctuate as much as those of delirium.  Dementia and delirium can co-exist, and an underlying dementia may make delirium more difficult to diagnose.

Delirium occurs as a result of a stressor on the body. Factors which can contribute to the development of delirium include chronic illness, surgery, infection, certain medications (sleep aids, allergy and pain medications, to name a few), alcohol or drug withdrawal, and metabolic imbalances.  Certain individuals are more likely to develop delirium when their bodies experience these stressors.  Risk factors include a history of a condition which impacts brain function such as dementia, Parkinson’s disease, or stroke; age (older folks are more susceptible); the presence of visual or hearing impairments; depression; and previous episodes of delirium.

How long does delirium last? The overall health of the individual and the ability to address the specific stressor which triggered the delirium will impact whether a delirium will last a few hours or a few weeks or months.  Individuals with dementia or other serious, chronic medical conditions may not completely recover from delirium, and may demonstrate a decline in cognition and physical functioning even after the episode of delirium has resolved.

The treatment of delirium will focus on the identification and treatment of the stressor which triggered the symptoms. Other interventions which will aid in the recovery process include measures to create a calm and comfortable environment such as low noise levels, a stable daily routine, consistent caregivers, adequate rest and nutrition, the presence of familiar objects, simple and clear communication, appropriate lighting for the time of day, and pain control.

Delirium, dementia, and depression all have a significant impact on quality of life, and a suspicion of any one of these conditions should be brought to the attention of a health care provider. Since delirium is a reversible condition, distinguishing its symptoms from those of an underlying dementia or depression is important in order for appropriate treatment to be initiated. Family members and friends can provide background information which is essential for a correct diagnosis as well as support to speed the recovery process.

Karen Kaslow, RN, BSN