Dementia, delirium and depression - referred to as the "3 Ds" - are common acute and chronic problems in the older adult. While it is possible for older adults to have more than one of these disorders, the three problems differ in diagnostic criteria and management. Therefore, it is essential to understand these diseases, quickly recognize them in older patients and help these individuals receive the most appropriate care.
Various Types of Dementia
Dementias are neuropsychiatric disorders that include widespread symptoms of memory loss and deficits in cognitive ability. The incidence of dementia increases with age, and is caused by a variety of other diseases. Of these disorders, Alzheimer's disease is the most common cause and accounts for 60 percent of all cases of dementia.1
Other common causes of dementia include vascular dementia (multi-infarct dementia), or dementia due to medical conditions such as Parkinson's disease, HIV or Creutzfeldt-Jakob. Older adults with dementia demonstrate impairment in at least three of the following spheres of mental activity: memory, language, visuospatial skills, abstract cognition, emotion and personality.
Dementia syndromes are commonly classified based on three clinical patterns: cortical, subcortical and mixed. Cortical dementias are caused by Alzheimer's and Pick's disease, and include cognitive deficits such as memory loss, aphasia, apraxia, agnosia, visuospatial and constructional difficulty, environmental disorientation, and impaired insight and judgment. There are generally no focal motor or sensory deficits that occur until the late stages of the disease.
Conversely, subcortical dementias manifest with signs of frontal lobe dysfunction including slowing of cognition, impaired ability to organize and retrieve information, motor impairment and involuntary movements. In these individuals, aphasia, apraxia and agnosia are absent and speech is hypophonic or dysarthric. Common forms of subcortical dementia include Parkinson's disease or normal pressure hydrocephalus.
Mixed dementia, most commonly caused by multi-infarct dementia, presents with a combination of cortical and subcortical clinical features. These individuals usually have focal neurologic symptoms such as hyperreflexia and extensor plantar responses, gait abnormality, incontinence, dysarthria, dysphagia and emotional lability.
In addition to the cognitive and functional changes associated with dementia, there are a number of behavioral manifestations that can occur. These patients may exhibit psychotic behaviors, paranoia and disruptive behavior including denial, wandering, apathy, restlessness, depression, emotional lability, disrupted sleep/wake cycle, repetitive actions and questions, and inappropriate social and sexual actions.
Clinically, dementia is differentiated from delirium in that dementia is a slow and persistent loss of intellectual function that occurs over months to years rather than an acute change that occurs over hours or weeks (see Table 1). Conversely, delirium is characterized as an acute disorder of attention and global cognitive functioning, and is particularly common in acute illnesses and in hospitalized older adults.
Delirium has complicated hospital stays for more than 2.3 million individuals, resulting in a cost of 17.5 million inpatient days, and accounted for at least $4 billion of Medicare expenditures related to hospitalization alone in 1994.1 Delirium often goes unrecognized in older adults due to a lack of awareness, as well as the challenges associated with the disease.
To facilitate the identification and diagnosis of delirium a simple method of evaluation, the Confusion Assessment Method (CAM), can be used (see Table 2).2 Delirium presents with an acute onset (hours to days) and fluctuating course of confusion, inattention and either disorganized thinking or altered level of consciousness. Lucid intervals are possible and can be misleading for the clinician.
Certainly, knowledge of the individual's baseline status is imperative in making a diagnosis of delirium. Inattention is commonly noted and presents with an inability to maintain attention to external stimuli. The patient may appear to be easily distracted by things in the environment, have trouble maintaining a conversation or follow a command and may persevere with answers to questions. Disorganized thinking, demonstrated by the presence of incoherent or disorganized speech, may occur.
The altered level of consciousness noted in the older adult with delirium is more likely to be lethargy. Other features of delirium include cognitive changes such as memory impairment, psychomotor agitation or retardation, and perceptual disturbances such as hallucinations, paranoid delusions, emotional lability and a sleep-wake cycle reversal. Disorientation and inappropriate behavior are sometimes used as symptoms of delirium. These symptoms, however, are also commonly found in dementia and depression and should not be considered indicative of delirium.
There are many risk factors and causes of delirium in the older adult: acute illness, e.g., infection, cardiac disease such as myocardial infarction or failure; dehydration; underlying cognitive impairment; sensory impairment (hearing, visual); psychoactive medication use; sleep deprivation; restraint use and change of location.
Delirium may occur, for example, in a patient with un.derlying cognitive or sensory impairment who has an acute illness. Alternatively, delirium may occur in an individual who is relatively resilient but is exposed to multiple noxious insults such as anesthesia, major surgery, multiple psychoactive medication, infection, decreased oxygen saturation or sleep deprivation.
Although major depression is less common in the elderly than in younger individuals, more than 2 million of the 34 million older adults (individuals 65 years of age and older) live with some form of depression.3 Despite these numbers, many older adults and professionals do not recognize the symptoms of depression and, consequently, adequate treatment is not given. Lack of treatment can have fatal outcomes, as the elderly are responsible for 25 percent of suicides and have a higher rate of completed suicide compared to all other age groups.
There are many contributing causes to depression including physical, psychological and social factors (see Table 3). Diagnosis of depression, however, is a major challenge for health care providers because its symptoms are easily associated with normal age changes or chronic medical problems and, overall, older adults are reluctant to seek treatment for depression. These symptoms can include: lethargy - feeling tired and not wanting to do anything; constipation; decreased appetite and loss of weight; decreased sexuality; difficulty concentrating; sleep problems; feeling worse in the morning; feelings of sadness, anxiety, fear and agitation; loss of pleasure in usual activities; social withdrawal; hopelessness (possible suicide attempts) and complaints of many somatic problems that become exaggerated.
Like care providers, older adults tend to associate their problems with medical or age-related changes, are concerned about the stigma related to depression and mental illness, and may be reluctant to take another medication.
The early stages of dementia (individuals with only mild cognitive impairment) have been treated with cholinesterase inhibitors, such as tacrine (Cognex®, Parke-Davis), donepezil (Aricept®, Roerig) or rivastigmine (Exelon®, Novartis). These drugs increase the amount of the neurotransmitter acetylcholine in the brain. Tacrine is of limited usefulness because of liver toxicity and the need for frequent dosing. Donepezil has been reported to decrease cognitive decline over a 6-month period.4 Rivastigmine has been shown to improve function and decrease caregiving needs of individuals with dementia.5 Vitamin E and ginkgo biloba have also been used in dementia with inconsistent findings regarding effectiveness.6-8
Dementia, which is not reversible, is best treated using a variety of management strategies such as avoiding medication that might worsen cognitive function, maintaining a safe nonrestrictive environment to facilitate functional performance and incorporating behavioral interventions (see Table 4). When necessary, additional treatments with antipsychotics and anxiolytics can also be used (see Table 5).
Treatment for delirium involves identifying and treating the underlying cause, such as infection, while using behavioral interventions (see Table 4), antipsychotics and anxiolytics as necessary until the delirium resolves. Ideally, interventions should be implemented to prevent delirium in older adults by identifying those at risk and avoiding precipitating factors. In particular, interventions that focus on the medical-neurochemical or pathophysiological causes of delirium should be considered.
Likewise, treatment for depression should initially attempt to determine specific factors that might be contributing to the condition and eliminate or decrease these factors if possible.
Medication may be effective in decreasing depression in the older adult, particularly when there are no known contributing factors. Existing antidepressant drugs are known to influence the functioning of certain neurotransmitters in the brain, primarily serotonin and norepinephrine, known as monoamines. Older medications, such as tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs), affect the activity of both of these neurotransmitters simultaneously. Note that TCAs and MAOIs are difficult to tolerate due to side effects or, in the case of MAOIs, have dietary and medication restrictions.
Newer medications, such as the selective serotonin reuptake inhibitors (SSRIs), have fewer side effects than the older drugs, making it easier for older patients to adhere to treatment. Both generations of medications are effective in relieving depression, although some people will respond to one type of drug but not another. Psychotherapy, cognitive-behavioral therapy and interpersonal therapy are also useful in the treatment of depression.
Dementia, delirium and depression are common problems noted in older adults. Nurses working with these individuals should be vigilant in implementing interventions to decrease the risk of delirium or depression - particularly in older adults who have an underlying dementia - and continually evaluating older individuals for each of these problems. Once identified, nurses should work with primary health care providers to be certain that appropriate interventions are implemented as soon as possible.
|Table 1: Characteristics of Dementia, Delirium and Depression
||Abrupt (Hours to weeks)
||Worse in P.M.
||Worse in A.M.|
||Impaired recent and remote
||Impaired recent and immediate
Table 2: Confusion Assessment Method (CAM) Algorithm*
I. Acute Onset and Fluctuating Course
- Is there evidence of an acute change in mental status from the patient's baseline? and
- Did this behavior fluctuate during the past day; that is, did it tend to come and go or increase and decrease in severity?
- Indicated by a positive response to the question: Does the patient have difficulty focusing attention, being easily distracted or having difficulty keeping track of what was being said?
III. Disorganized Thinking
- Indicated by a positive response to the question: Is the patient's speech disorganized or incoherent, such as rambling or irrelevant conversation, unclear or illogical flow of ideas?
IV. Altered Level of Consciousness
Table 3: Factors Contributing to Depression
- Physical Illness
- A low thyroid
- Parkinson's Disease
- Certain Cancers
- Acute illnesses or comorbidity (vascular & musculoskeletal disease)
- Drugs- particularly painkillers, alchohol, some types of blood pressure pills and tranquilizers
- Chemical imbalance in the brain
- Fear of dependency or loss of function
- Past history of psychological problems
- Feelings of inadequacy compounded by losses related to aging
- Loss of family/friends, income, social stature, home
Table 4: Treatment of Depression
- Treatment of medical illnesses causing depression
- Review of drugs that may cause depression
- Counseling and treatment of addiction problems such as alcoholism
- Good nutrition and exercise
- Antidepressant drugs (selective serotinin reuptake inhibitors; tricyclic antidepressants; MAO inhibitors)
- Electroconvulsive therapy
- Verbal therapy (individual or group)
- Specific psychotherapies (cognitive behavioral therapy)
- Encourage and arrange social activities
- Encourage structured activities
- Group exercise activities and programs
|Table 5: Pharmacologic Treatment for Behavioral Management in Dementia and Delirium
|Drug (Mood Stabilizers)
||Indications For Use of Drug Group
||50 - 80 mg/day
||Agitation, aggression labile depression manic depression
||Leukopenia, rash, hepatotoxicity, ataxia, enzyme inducer, and cardiac and thyroid effects|
|200 - 750 mg/day
||Agitation, aggression labile depression manic depression
||Sedation, hepatotoxicity, thrombocytopenia, weight gain, enzyme inhibitor|
Barbara Resnick is an associate professor at the University of Maryland School of Nursing, Baltimore.