DELIRIUM AND DEMENTIA

DELIRIUM AND DEMENTIA

Delirium and dementia are common in the geriatric population. Subsequent impairment of executive functioning impacts the patient's mobility, ADLs, and IADLs.

The effects of delirium and dementia can be detrimental to the patient's functional recovery in the rehabilitation setting and in everyday situations.

DELIRIUM

Delirium is a disorder of attention. The DSM-IV defines delirium as a fluctuating level of consciousness and pervasive impairment in mental, behavioral, and emotional functioning. It is usually of acute onset and temporary. Delirium is frequently caused by physical disease or drug effects.

Hypoactive and hyperactive subtypes of delirium are described. The hypoactive variant, in which decreased psychomotor activity is present, is more common.

Strong stimuli are often needed for arousal, which is incomplete and transient. However, patients with hyperactive symptoms, such as agitation, are more likely to be identified than patients with the hypoactive variant.

Hallucinations occur in 40% of patients with delirium and can accompany both subtypes. Visual hallucinations are more common than auditory hallucinations. Delirium can be worse at night and is often referred to as sundowning in the geriatric population. Symptoms of delirium may persist for hours to weeks. The differential diagnosis of delirium includes psychotic disorders, dementia, and epilepsy.

CAUSES OF AND RISK FACTORS FOR DELIRIUM

Delirium often occurs as a direct physiologic consequence of a general medical condition. Common examples are anemia, uremia, hypoxia, hypoglycemia, infection, inflammatory conditions, stroke, heart failure, liver failure, pulmonary emboli, and cancer.

Other conditions associated with delirium include sleep deprivation, sensory impairment, incontinence, fecal impaction, and dehydration.

Delirium commonly occurs as a result of substance intoxication or medication use. Drugs that are commonly associated with delirium are anticholinergics, sedative-hypnotics, narcotics, histamine-receptor blockers, and agents used to treat Parkinson disease.

Other associated agents include tricyclic antidepressants, lithium, neuroleptics, and gastrointestinal and cardiac medications. Delirium also can occur when the substance is withdrawn.

Delirium is detected in only 30-50% of affected patients. The risk of delirium is higher in severely ill patients with comorbid medical problems, in patients older than 80 years old, and in those with impaired physical function.

Other risk factors include preexisting cognitive impairment, electrolyte abnormalities, hypoalbuminemia, polypharmacy, sensory deprivation, and a history of trauma.

The hospital environment is often a cause of heightened delirium. Hospital mortality rates have been reported to be 2-20 times higher in patients with delirium. Also, prolonged hospitalization, impaired physical function, and increased rates of nursing home placement are correlated with delirium.

Other consequences of delirium in the geriatric population are deconditioning, immobility, decline in ADL and IADL functioning, social isolation, dehydration, malnutrition, aspiration pneumonia, and pressure sores.

Prolonged cognitive dysfunction may also leave permanent memory problems. Delirious patients also have a significant risk of suicide. The risk for overall mortality following an episode of delirium remains high, even after 2 years after the acute episode.

SCREENING FOR DELIRIUM

Because postoperative delirium is common in the geriatric population, geriatric patients should be screened during the preoperative visit.

Factors that increase the risk of delirium in the surgical population include existing dementia, low cardiac output, perioperative hypotension, postoperative hypoxia, and use of anticholinergic drugs.

Predictors of postoperative delirium may include advanced age; poor cognitive function at baseline; poor physical function; self-reported alcohol abuse; abnormal serum sodium, potassium, or glucose levels; aortic aneurysm surgery; and noncardiac thoracic surgery.

Rates of delirium have been reported to be as high as 15% after general surgery and as high as 61% after orthopedic surgery.

Acute confusional states have also been reported in patients undergoing open-heart surgery. The intraoperative use of meperidine has been shown to increase the risk of postoperative delirium.

Postoperatively, hypoxia and hypercapnia have been shown to contribute to a state of delirium; therefore, oxygen saturations must be monitored closely.

With a preoperative geriatric assessment and the management of medical conditions and medications, rates of postoperative delirium can be decreased from 61.3% to 47.6%.

Preventive interventions in the hospital or outpatient rehabilitation setting are available to identify risk factors for delirium in the elderly patient.

Cognitively stimulating activities (eg, discussing current events) and reorienting the patient to his or her surroundings several times a day can decrease the risk of cognitive impairment.

Active exercise programs can also help in preventing immobility, which can be an associated factor.

Relaxing music, massage, and noise reduction at bedtime may help to decrease sleep deprivation.

Visual and hearing aids can improve sensory impairments. Volume repletion can decrease the incidence of dehydration if no fluid restrictions exist. The use of a beverage cart on the ward or a pitcher at bedside on the inpatient setting has been suggested.

EVALUATION FOR DELIRIUM

Thorough history taking and physical examination are necessary in the acute stage of delirium. The history must include data regarding new functional impairments, incontinence, impaction, hallucinations, and alcohol use.

A nutritional assessment to rule out malnutrition or dehydration is important. Prescription and OTC medications must be reviewed.

The FIM and IADL scores should be documented on a daily basis to detect any functional changes.

The physical examination should focus on vital signs (especially in patients with fever or hypothermia) and oxygen saturation. Checking for skin breakdown and screening for sensory deficits are also important.

The Mini-Mental Status Examination (MMSE) is helpful in determining delirium.

MMSE scores less than 24 are considered abnormal with the attention, concentration, and recall subscales being the most sensitive for detecting delirium. Screening with 3-item recall and reciting the days of the week backward are especially sensitive.

The Confusion Assessment Method (CAM) also can be used to clinically diagnose delirium. An acute onset, a fluctuating course of delirium during the day, and inattention must be present.

The patient must also have either disorganized thinking (rambling, illogical flow of ideas) or an altered level of consciousness (hyperalertness, lethargy, stupor, and coma). The neuropsychologist can be helpful in assessing baseline cognitive function; he or she can use cognitive testing to monitor any changes. The etiology, however, must be further explored.

Infection and other medical causes (metabolic, cardiovascular, or neurologic conditions) must be identified and treated if present.

Laboratory tests based on history and physical findings may include LFTs and a determination of the CBC count and vitamin B-12, thiamine, folate, heavy metal, drugs (eg, narcotics, alcohol), TSH/T4, and albumin levels.

A basic metabolic panel (BMP), HIV testing, urinalysis, culture and sensitivity testing, chest radiography, and electrocardiography may also be helpful.

Immediate management starts by discontinuing unnecessary medications. Acute symptomatic control may require risperidone, carbamazepine, trazodone, or a benzodiazepine. If these medications are the cause of the delirium, they must be discontinued slowly. If the delirium is secondary to alcohol use, administer thiamine in the acute stage.

Direct wording, simple questions, simple instructions, and a calm approach are ideal for good communication with the patient experiencing delirium. Avoiding excessive noise because stimulation can decrease agitation.

Education of the nursing staff and family are important because they can help to monitor the frequency and duration of changes in the patient's mental status and function during the day.

Caregivers and family members should visit or call the patient often. Close supervision by a nighttime sitter or assigning the patient to a room near the nursing station in a hospital may be of assistance.

Continuously orienting the patient throughout the day should be a part of rehabilitation. A clock with large numbers, a calendar, and a fixed daily activity schedule should be visible to the patient in his or her room.

The environment should be modified if the patient has any sensory deficits; for example, the bathroom light can be left on at night. Photos and a personalized environment should also surround the patient's room.

Patients should have ready access to news and radio stations with current events. The patient should leave his or her room and be involved in physical activities at least once daily.

DEMENTIA

Dementia is a problem with decline in memory and at least 1 other cognitive function (eg, aphasia, apraxia, agnosia, executive function).

The World Health Organization defines dementia as memory decline, especially in the learning of new information, lasting longer than 6 months.

Dementia is not a normal part of aging. Dementia disrupts one's daily activities and leads to a decline in memory and previous functioning, and it can also lead to social impairment.

The diagnosis is based on the gradual onset of cognitive impairment and continuing decline. The diagnosis is made when all other possible causes of cognitive impairment are ruled out. These other causes include medical, neurologic, and psychiatric problems.

Dementia must be differentiated from delirium. If diagnosed early, the patient has the opportunity to be involved in his or her own medical-care decisions.

AD [Alzheimer Disease] is the most common cause of dementia. AD is the etiology of 60-70% of the geriatric population with dementia. The prevalence of AD doubles every 5 years after the age of 60 years; therefore, by the age of 85 years, 30% of the population has AD.

Vascular dementia, or multi-infarct dementia (MID), is the etiology in 15-25% of cases of dementia in the elderly. Compared with AD, MID has a more abrupt onset and is associated with hypertension. Patients tend to be younger at onset, and the predominance is slightly higher in males than in females. Often, insight is preserved, but personality can be labile, and the gait usually is abnormal.

Transient focal neurologic signs, such as dysphagia or seizure activity, may also be observed. MID is also associated with a higher 3-year mortality rate and a higher rate of institutionalization than those seen in AD.

Potentially reversible dementia affects 2-5% of the elderly with dementia; such dementia may be the result of drug toxicity, metabolic disturbances, subdural hematoma, hydrocephalus, syphilis, hyperthyroidism or hypothyroidism, vitamin B-12 or niacin deficiency, or hypocalcaemia. However, the degree of reversibility may be limited if permanent neurologic damage persists.

Non-cognitive symptoms are also associated with dementia. Psychotic symptoms occur in approximately one third of patients with AD. Delusions are usually accusatory or paranoid. Hallucinations are usually visual.

RISK FACTORS FOR AD

Definite risk factors of AD include advanced age and a family history. Familial AD, which has associated genetic mutations on chromosomes 1, 14, and 21, may begin prior to the age of 60 years.

Down syndrome and the apolipoprotein allele-4 (APOE-4) have also been shown to be significant risk factors. Other possible risk factors are head trauma, clinical depression, and a low educational level.

Small head circumference and small brain size have been associated with an early onset of AD. Women are at greater risk than men, even after the longer life expectancy of women is eliminated.

Patients in high-risk groups should undergo neuropsychological testing with a focus on a mental-status evaluation.

Protective factors may be an APOE-2 genotype, NSAID use, estrogen therapy, and antioxidant use. Higher levels of education are associated with a delay in the onset of AD.

EVALUATION FOR AD

The evaluation of possible dementia includes good history taking (which may involve talking with the patient's family or friends), physical examination, and a formal MMSE.

An assessment of the patient's functional status, which includes an evaluation of his or her mobility and ability to accomplish ADLs and IADLs, should also be performed.

In the workup of dementia, laboratory tests that are typically ordered include:

Ø  LFTs

Ø  Serologic tests for syphilis

Ø  Urinalysis for heavy metals and determinations of CBC count

Ø  BMP

Ø  TSH / T4

Ø  Vitamin B-12

Ø  Folate & calcium levels

If vascular dementia is suspected, MRI should be performed. Non-enhanced CT can be helpful in ruling out a space-occupying lesion or hydrocephalus.

Positron emission tomography (PET) or single photon emission CT (SPECT) might provide possible evidence of AD. With these neuroimaging studies, decreased glucose metabolism and low blood flow in the temporal and parietal regions are associated with AD.

STAGES OF AD

Four stages of AD that are well recognized in the literature.

The First Stage is preclinical and defined as mild cognitive impairment. The patient with preclinical AD has delayed recall but no other cognitive or functional impairments. The MMSE score is 26-30.

The Second Stage consists of a slightly higher degree of cognitive impairment and usually occurs 1-3 years after the onset of symptoms. The patient has difficulty with recent recall, anomia, orientation to date, visuospatial activities, problem solving, and insight. Problems with some IADLs, including managing finances and medications, are noticeable. Also observed are mood changes, including irritability; these can lead to social isolation. The MMSE score is 22-28 in this stage.

The Third Stage is moderate impairment, and this is usually recognized 2-8 years after the onset of symptoms. The patient has a decreased ability to learn new information; their retention can be as short as a few minutes. They may also have difficulty calculating numbers, comprehending simple questions, and orienting themselves to date and place.

Functional impairment is more significant in this stage, and the patient experiences difficulty with basic ADLs, primarily dressing and grooming. The patient also has difficulty with a wider range of IADLs, particularly using a telephone, cooking, planning meals, shopping, and banking. Impaired judgment, delusions, agitation, aggression, and wandering (including getting lost while driving) may be prominent in this stage. The MMSE score is 10-21.

The Fourth Stage occurs when the patient is severely impaired, and it usually occurs 6-12 years after the initial symptoms appear. The patient has impaired remote memory and an inability to write or copy figures.

He or she may also be unintelligible when communicating. The patient is often incontinent at this stage and completely dependent on others to help with ADLs and IADLs. The MMSE score is 0-9.

TREATMENT OF DEMENTIA

The treatment of dementia revolves around improving the patient's quality of life and maximizing his or her functional performance by focusing on cognition, mood, and behavior.

Identifying any underlying medical cause or contribution to dementia is the first step. The environment should be stable, and a change of residence should not be considered to maintain familiarity in the person's surroundings.

Behavioral techniques (eg, distraction), environmental modification (eg, increasing the level of stimulation), music therapy, and massage therapy are important in the care of a patient with dementia and behavioral problems.

Increased sunlight exposure may be beneficial in increasing the sleep-wake cycle and positively affecting the patient's behavior. Sleep hygiene also includes restriction of naps, fluid intake at night, and use of stimulants (eg, caffeine, which has been noted to increase risk of accidents and wandering). Moderate exercise early in the day, supervision, use of a bedside commode, and keeping the room cool and quiet may also help.

Education of the family or caregiver is pivotal to the patient's care. The patient's cognitive and functional strengths and weaknesses must be presented so that the caregiver is aware of any changes, which may mark a decline. Reasonable therapy goals and expectations should be discussed.

The caregiver must also monitor the patient's behavior (alertness, initiative, aggression, agitation), and he or she should be taught how to handle potential problems. Behavioral decompensation may also indicate infection, injury, or fecal impaction; this must be formally evaluated.

It is helpful for the patient to maintain a daily routine that provides structure to his or her life. The patient should continue performing ADLs and IADLs every day.

Occupational therapy can help with techniques to correct individual disabilities and teach caregivers the essential needs of the patient's self-care activity.

Greater physical activity has been associated with lower risk of cognitive impairment and dementia of any type. Physical therapy should also be incorporated into the patient's daily life; for instance, frequent walks should be included.

Physical therapy can also help in improving the patient's balance and the safety of his or her transfers; these are generally affected in patients with dementia. Procedural learning (learning by performing the activity) should continue, even if declarative learning (learning by verbal instruction) is impaired.

Indicators of psychological distress among caregivers are physical illness, isolation, and anxiety. The patient's physician must be aware of caregiver stress because clinical depression is seen in 50% of those caring for patients with dementia.

The increased degree of dependence in ADLs in the later stages of dementia may be predictive of caregiver distress. Access to educational information about dementia is also important for family members who are not located near the patient but still interested in their family member's care and well-being.

Social workers can offer community resources, including respite and daycare programs to alleviate stress that caregivers may face. One study demonstrated that daycare programs help in maintaining stability in the cognitive function of patients with mild-to-moderate dementia, although the programs do not decrease agitation.

Social workers can also offer the patient community social activities to help increase stimulation and help to decrease social isolation, especially in the early stages in which the patient is not fully dependent. Social workers can also help in making arrangements regarding legal issues, which may include financial planning and the establishment of advanced directives.

A neuropsychologist should follow up the patient's MMSE results with serial visits, especially if changes are noted in the caregiver's report. Physiatric FIM scores and IADL scores should also be recorded to prescribe the appropriate rehabilitation at each stage.

Medications are also important in the management of dementia.

Cholinesterase inhibitors are being used in the mild-to-moderate stages of dementia to try to slow the patient's cognitive decline, which may delay his or her placement in a nursing home. Donepezil, rivastigmine, and galantamine are all cholinesterase inhibitors that are showing promising effects.

Neuroprotective agents, such as vitamin E (up to 2000 IU/d) and selegiline have retarded the progress of AD and reduced losses in the ability to perform ADLs.

Trazodone or buspirone is useful in the geriatric patient with anxiety or mild-to-moderate irritability, although watching for orthostatic hypotension is imperative.

In men, sexual aggression or impulse-control problems can be treated with estrogen or medroxyprogesterone.

CONCLUSION

Delirium and dementia are of immense concern in the geriatric population. Awareness of any cognitive and behavioral changes in the elderly patient is crucial when focusing on rehabilitation.

These changes significantly affect the quality of life of the patient and of his or her caregivers and family members.