Chapter 288: Mental Health Disorders of the Elderly

This chapter discusses the diagnosis and differentiation of delirium and dementia in the elderly and provides an overview of selected common mental health disorders in the aging population.

The proportion of ED visits by older adults continues to increase with the exponential growth of the geriatric population.¹ Delirium, dementia, and depression can affect older adults, and the disorders are often interrelated. It can be difficult to identify delirium in patients with dementia, particularly because individuals with dementia are more likely to develop delirium.² Patients who develop delirium are more likely to develop dementia later in life.^3,4,5,6 Distinguishing between dementia and delirium is an important aspect of caring for older patients.

It can also be difficult to diagnose depression in patients with dementia given that both can present with similar symptoms such as apathy.⁷ Also, depression in late life has been associated with increased risk of developing dementia, further demonstrating that dementia, delirium, and depression are interconnected, increase the risk of each other, and are all associated with increased risk of mortality and morbidity.^{8,9,10,11,12,13,14} Table 288-1 provides distinguishing features of delirium, dementia, and psychiatric disorders. Chapters 168, "Altered Mental Status and Coma," and 286, "Mental Health Disorders: ED Evaluation and Disposition," also discuss the distinctions between delirium, dementia, and psychiatric disorders.

Delirium is an acute change in cognition that fluctuates rapidly over time and is often reversible.¹⁵ Delirium is frequently the first sign of underlying acute medical illness. Patients demonstrate altered levels of consciousness, inattention, disorganized thinking, and altered perception.¹⁵ There are three main types of delirium: hypoactive, hyperactive, and mixed.¹⁶ By far, the most common types are hypoactive and mixed delirium, which also have the highest potential to be missed.^{17,18,19,20,21,22,23} Hypoactive delirium has been called "quiet delirium" because patients have decreased psychomotor activity and can appear somnolent. If hypoactive delirium is confused for depression, the underlying medical disorder causing the delirium can be missed.^24,25,26 Hyperactive delirium, in contrast, is characterized by increased psychomotor activity, and patients are often agitated, anxious, and sometimes combative. Mixed type can present with a combination of both hyperactive and hypoactive states that fluctuate over time.

Delirium is thought to be present in 7% to 10% of older patients presenting to the ED.^17,27,28 Environmental risk factors for delirium include functional dependence, living in a nursing home, and hearing impairment.^17,29 Delirium is an independent marker for mortality and is associated with a longer length of hospital stay than the median, increased hospital complications, discharge to long-term care facilities, and lasting cognitive deficits.^{30,31,32,33,34,35,36,37} Even though delirium is a common disorder in the elderly, the diagnosis is missed by providers in 57% to 83% of cases.^{27,38,39,40,41} If delirium is missed in the ED, it is likely to be missed on the inpatient services as well.¹⁷

CLINICAL FEATURES

The differential diagnosis of delirium includes dementia, depression, or another underlying psychiatric disorder. Such conditions can also be comorbidities of each other. However, first assess for delirium and then consider the possibility of the other disorders.

History

Focus history taking on identifying the patient's baseline mental status and level of functioning and the time course of changes. Ask about past medical history and recent illness. Obtain an accurate medication list, and ask about over-the-counter medications, medications with anticholinergic properties, or any new medications.⁴² Ask about substance abuse to assess the likelihood of intoxication or withdrawal. Any past psychiatric history requires close investigation of prior diagnoses, hospitalizations, and medications. Determine the patient's ability to make informed medical decisions, and determine whether another individual has legal power of attorney for medical decision making.

When attempting to differentiate delirium from dementia, consider several key factors. An acute change in mental status is more consistent with delirium than with dementia, and a fluctuating course over time is also more likely due to delirium.⁴³ Altered level of consciousness, inattention, and disorganized thinking are all more common in delirium than in dementia.⁴³

Physical Examination

The physical examination should be thorough. Vital signs must be complete, to include oxygen saturation and temperature. Determine the blood glucose level. Baseline blood pressures may be higher than in younger age groups, and tachycardia can be masked by pharmacologic and/or physiologic limitations. Older patients have lower basal temperatures, with means of 97.3 to 97.8°F depending on the time of the day, so the threshold for a fever is lower than the assumed "normal" of 98.6°F.⁴⁴ Look for evidence of trauma, as patients may not recall falling or injuring themselves. Examine the entire body, making sure to look at the patient's back and heels for evidence of decubitus ulcers. Perform a complete neurologic exam, checking for focal findings, abnormal posturing, or difficulty with gait, coordination, or vision. A normal physical examination does not exclude the diagnosis of delirium.

Mental Status Examination

Mental status examination is performed to identify delirium and differentiate it from other conditions.^{27,35,38,39,40,41,45,46} The examination consists of an assessment of six mental-behavioral components (Table 288-2).

Two of the most common screening tests used to detect delirium are the Confusion Assessment Method for general use and the Confusion Assessment Method–Intensive Care Unit for intubated patients who are not heavily sedated.^47,48 Figure 288-1 demonstrates the components of the Confusion Assessment Method. Inattention is characterized by an easily distracted patient who has difficulty keeping track of the conversation. Disorganized thought processes are rambling, unclear, or illogical. An altered level of consciousness is lethargy, lack of responsiveness, or coma—essentially anything other than alert. The diagnosis of delirium requires features 1 and 2 and either 3 or 4. See Table 288-3 for further details about using the Confusion Assessment Method and the Confusion Assessment Method–Intensive Care Unit.^47,48

Laboratory Testing and Imaging

Laboratory testing and imaging are obtained to identify the treaTable causes of delirium (Tables 288-3 and 288-4).⁴⁶

In geriatric patients, infections, such as urinary tract infections and pneumonia, are associated with nearly half of cases of delirium,⁴⁹ and medications may account for another 40%.^50,51,52

Laboratory Testing Check point-of-care glucose as soon as possible after patient arrival in the ED. Obtain CBC and basic metabolic studies, including calcium, phosphorus, and hepatic enzymes. Urinalysis is necessary because urinary tract infections are a frequent cause of delirium. Obtain cardiac markers. Consider an arterial blood gas analysis, especially in patients with chronic lung disease, because hypercarbia can cause delirium.⁴² Obtain thyroid function studies.⁵³ Urine or serum toxicologic studies may be in order. Lumbar puncture may be necessary (after CT scan) if there is suspicion for meningitis or encephalitis or if the patient has had a new-onset seizure.⁴³ Further studies may be needed depending on the results of history, examination, and basic tests.

Imaging/Ancillary Tests Electrocardiogram and chest radiograph are essential.⁵⁴ Head CT scan is advised for patients with signs of, or a history of, trauma, focal neurologic deficits, impaired level of consciousness, or an otherwise unrevealing evaluation.^55,56

TREATMENT

Medical Treatment

Direct treatment to the underlying cause of delirium. Withhold or remove medications that are responsible for delirium. Treat infection, provide IV fluids for dehydration, correct hypoglycemia, and treat pain. Select doses of analgesics and narcotics for each individual patient and monitor for adverse effects.

The Medical Environment

Provide the patient with his/her glasses or hearing aids, allow family or caregivers at the bedside, provide frequent reorientation about surroundings and course of care, and make sure there is access to a bathroom.⁵⁷ The Multicomponent Intervention to Prevent Delirium in Hospitalized Older Patients identified six risk factors (cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration) for the development of delirium and targeted each risk factor with specific interventions carried out by a multidisciplinary team.⁵⁷ Precipitating factors in the development of delirium in the hospital include the use of physical restraints, malnutrition, use of a bladder catheter, more than three medications added, and any iatrogenic event.⁵⁸ Preventing and minimizing these factors are especially important when long ED stays are unavoidable.

Agitation

If the patient is agitated, begin with a nonpharmacologic approach by addressing patient needs (such as using the restroom and, if possible, allowing the patient to eat or drink), providing comforTable surroundings, and having the family close by.^57,59 Avoid bladder catheters. Physical restraints should be an absolute last resort. If basic interventions are not successful, consider medication (Figure 288-2). We recommend the avoidance of benzodiazepines in the elderly if at all possible, unless alcohol withdrawal is the cause of delirium.⁶⁰ Benzodiazepines can cause paradoxical disinhibition and increased agitation in the elderly. If a benzodiazepine is used, consider a short-acting, glucuronidated agent such as lorazepam, oxazepam, or temazepam to minimize prolonged benzodiazepine effects. Avoid antihistamines, because this drug class has strong anticholinergic effects and can induce or worsen delirium in the elderly.

DISPOSITION AND FOLLOW-UP

The vast majority of patients with delirium should be hospitalized. Criteria for possible discharge include identification and treatment of the source of delirium; the patient returns to baseline function and mentation in the ED; the patient is discharged to the care of an active, capable individual or to a responsible facility; and the patient has access to follow-up in 24 hours or has the ability to return immediately to the ED if conditions deteriorate. Patients with unrecognized delirium who are discharged home are less apt to understand discharge instructions and less likely to seek further treatment, underscoring the importance of screening for delirium in geriatric patients.⁶¹

Dementia is a general term used to describe several types of disorders that gradually cause loss of cognitive functioning in two or more aspects of a person's life. The Diagnostic and Statistical Manual of Mental Disorders, fourth edition, definition of dementia requires memory impairment and at least one of the following: aphasia, apraxia, agnosia, or disturbance in executive functioning.¹⁵ The diagnosis cannot be made in the setting of delirium, and the patient must show a decline in previous level of functioning that impacts social, functional, or occupational activities.¹⁵ The most common form of dementia is Alzheimer's dementia, which affects approximately 5 million people in the United States.⁶² Alzheimer's dementia is reported in 6% to 8% of those >65 years old and in ≥30% of those >85 years old.⁶³ Some other common types of dementia are vascular dementia, Lewy body dementia, frontotemporal dementia, dementia associated with Parkinson's disease, and mixed dementia.

PATHOPHYSIOLOGY

Alzheimer's disease has a gradual onset and primarily affects memory. The disease can also result in personality changes and visual-spatial problems.⁶² Vascular dementia characteristically has a sudden or stepwise onset, and symptoms typically correlate with the area of brain ischemia.⁶² Lewy body dementia has a gradual onset and presents with deficits in memory, and patients will also frequently have hallucinations and parkinsonian-like features.⁶² Patients with Lewy body dementia do very poorly when given typical antipsychotics, so avoid them in these patients.^64,65 Patients with Lewy body dementia also frequently resemble patients with delirium given that patients can have a rapid decline, fluctuating course, and perceptual disturbances.⁴³ Frontotemporal dementia often presents in patients <60 years old and is associated with disinhibition, apathy, language difficulties, and atrophy in the frontal and temporal lobes.⁶²

CLINICAL FEATURES

The main pharmacologic therapy for patients with dementia is cholinesterase inhibitors. The side effects of these medications include GI upset, anorexia, urinary incontinence, bradycardia, dizziness, and abdominal cramps; patients may come to the ED secondary to such complaints.⁶²

Behavioral disturbances are frequently encountered in patients with dementia and are common reasons for ED presentation, especially when caregivers are feeling overwhelmed. The first steps are to screen for delirium and to identify the presence of a comorbid medical disorder (see earlier discussion and Tables 288-1, 288-3, and 288-4, and Figure 288-1). Subsequent management strategies for agitation are listed in Figure 288-2.

Mental Status Examination

Perform a mental status exam on all geriatric patients because patients with dementia can often appear intact if formal evaluation is not performed. The Mini-Mental State Examination can be used to assess for dementia when there is appropriate time to administer the exam, but it is lengthy, and copyright restrictions sometimes limit access.⁶⁶ In the ED, short screening tests such as the Mini-Cog, which takes 3 minutes to complete, are more efficient. The Mini-Cog (Figure 288-3) combines a three-word recall with a clock drawing test.⁶⁷ Ask patients to remember three words (e.g., apple, table, penny). Then ask them to immediately repeat the words and remember them. Three minutes later, ask for the three words again. If patients can recall all three words, they do not need to complete the clock drawing test and do not have signs of cognitive impairment. If patients are not able to recall any of the words, assume cognitive impairment, and the clock drawing test is not needed. If patients recall one or two words, they will need to perform the clock drawing test. Ask the patient to draw a specific time, indicating hour and minute. The test is graded as either normal (negative for cognitive impairment) or abnormal (positive for cognitive impairment).⁶⁷ Alternatively, while waiting the 3 minutes to test the patient's recall, ask the patient to draw the clock, as valuable information can be obtained from that exercise alone.

As the population of older adults continues to increase, so will the number of geriatric patients with mental health disorders. One estimate predicts that the number of geriatric patients with mental illness will increase by 275% from 4 million in 1970 to 15 million in 2030.⁶⁸ Emergency medicine providers need to feel comforTable identifying and managing common mental health disorders in geriatric patients. A recent meta-analysis revealed that the mental health disorders with the highest estimated prevalence rates among geriatric patients were major depression and alcohol use disorders.⁶⁹ Significant research remains to be done in the field of geriatric psychiatry. The next sections will give a short overview of what is currently known regarding several mental health disorders found in older patients including depression, bipolar disorder, schizophrenia, and eating disorders.

DEPRESSION AND SUICIDE

Although the prevalence of major depressive disorder among community-dwelling older adults is low (1.4% to 4.4%), the proportion of patients with symptoms of depression below the threshold of major depressive disorder can be quite high, with most studies reporting around 8% to 16%.^7,70,71 Older patients with overt and subclinical depression can benefit from treatment.⁷²

Depression in the geriatric population is associated with chronic medical illness, disability, increased use of health services, and poor health outcomes.^7,72,73 Risk factors associated with development of depression in older adults include lack of social support, living alone, being unmarried, cognitive impairment, bereavement, and lower socioeconomic status.^7,73

Depression presents differently in older adults compared to younger age groups. Older adults with depression frequently report loss of appetite or sexual interest, rather than crying spells, feeling sad, or feeling like life is a failure.⁷ They are more likely to be irriTable and withdrawn than appear sad.⁷⁴ Older patients may also present with somatic or cognitive complaints when they are actually suffering from depression, which can make the diagnosis difficult.⁷ Caregivers and patients themselves may attribute depressive symptoms to normal aging, again making the diagnosis difficult.⁷ Comorbid anxiety is common with depression, and generalized anxiety disorder is frequently seen in the elderly population, with a reported lifetime prevalence of 15% in older adults.⁷⁵

There are several screening tests for depression currently available to practitioners. Many are lengthy and would be difficult to use in the ED setting. The Patient Health Questionnaire-2 and Patient Health Questionnaire-9 are two- and nine-item self-administered questionnaires that have been developed to screen for depression based on Diagnostic and Statistical Manual of Mental Disorders, fourth edition, criteria.⁷⁶ The Patient Health Questionnaire-9 assesses nine features of depression: anhedonia, depressed mood, trouble sleeping, feeling tired, change in appetite, guilt or worthlessness, trouble concentrating, feeling slowed down or restless, and suicidal thoughts. The Patient Health Questionnaire-2 has two questions addressing anhedonia and low mood.⁷⁶ See Table 288-5 for the Patient Health Questionnaire-2.⁷⁷ Both questionnaires can easily be located and have been found to be comparable to longer scales used to screen for depression with more evidence supporting the use of the Patient Health Questionnaire-9.⁷⁸ Several sources recommend starting with the Patient Health Questionnaire-2 and, if positive, then administering the Patient Health Questionnaire-9. It is important to find a screening test that you are familiar with and use it to screen for depression.

Screening for suicide is vital in the assessment of geriatric patients with depression.⁷⁹ People >65 years old have the highest rates of completed suicide of any age group.⁸⁰

Older adults may give fewer warning signs of suicidal intent, and they are more successful in attempting suicide.⁸¹ Depression is the largest risk factor for suicide. Other risk factors include perceived poor health status, poor sleep quality, alcohol abuse, absence of a confidant, physical illness, functional decline, and presence of a firearm.⁷⁹

Treatment combines both nonpharmacologic and pharmacologic interventions.⁷ It is unlikely that new medications will be started in the ED for depression in geriatric patients, but recognizing depressive symptoms and assuring that the patient has appropriate follow-up are important. Review antidepressant doses, side effects, and drug interactions, as ED visits may be precipitated by symptoms from side effects or interactions. Selective serotonin reuptake inhibitors and selective norepinephrine reuptake inhibitors are some of the most frequently prescribed and effective antidepressants, but they can be associated with serotonin syndrome.⁷

SUBSTANCE ABUSE

Substance abuse is relatively common in the geriatric population and may increase with the baby-boomer cohort.⁸² One estimate is that the number of older adults who will need substance abuse treatment is expected to increase from 1.7 million in 2000–2001 to 4.4 million in 2020.⁸² Although the vast majority of substance abuse in the elderly is related to alcohol and prescription medications, there are reports of increased illicit drug use as well, highlighting the need to ask all patients about drug use.⁸³

Alcohol abuse in geriatric patients specifically is frequent. In a cross-sectional study of 12,000 geriatric primary care patients, 15% of patients were felt to be at risk for, or were affected by, problem drinking.⁸⁴ Other community surveys estimate the prevalence of at-risk or problem drinking to be between 1% and 15%.^85,86,87 The current recommendation is that older adults consume no more than one standard drink per day or seven standard drinks per week.⁸⁸ Alcohol-related problems, such as falls, confusion, and malnutrition, may be attributed to normal aging, and thus alcohol abuse may be missed.⁸⁸ Physiologic changes from advancing age may also change alcohol tolerance, increasing risk for complications.⁸⁸ If at-risk drinking is identified, refer the patient to an inpatient or outpatient treatment facility. Also, if the plan is to admit a patient with known alcohol or substance abuse, notify the admitting physician so plans can be made to mitigate withdrawal.

BIPOLAR DISORDER

Bipolar disorder is a spectrum of illness that affects an individual's ability to regulate mood. There are four types: type I, which requires a manic episode for the diagnosis; type II, which requires one or more depressive episodes and a hypomanic episode; cyclothymia (cycling moods that do not meet criteria for depression or mania); and bipolar not otherwise specified.⁸⁹ Research regarding bipolar disorder in older adults is limited. The prevalence of bipolar disease in older adults is reported to be approximately 0.08% to 0.5%.⁸⁹ Given this low rate, older adults who present with new-onset mania require a complete medical evaluation before a new diagnosis of bipolar disorder should be made. Even though the prevalence rate of older adults in the community with bipolar disorder is low, one study found that 17% of patients >60 years old presenting to a psychiatric ED carried a diagnosis of bipolar disorder.⁹⁰ There are some differences between younger and older patients with bipolar disorder. Older people with bipolar disorder are more likely to be female. Late-onset bipolar disorder (onset between age 30 and 50 years) is associated with fewer genetic associations and more neurologic illnesses.⁹¹ The frequency of psychotic features is essentially the same in young and old patients with bipolar disorder.⁹¹ Older patients with bipolar disorder can have either early- or late-onset disease.

The treatment and adverse effects of treatment of bipolar disorder have implications in the elderly. One of the most customary treatments for bipolar disorder is lithium, which is a mood stabilizer.^92,93 Older patients can demonstrate beneficial effects at lower serum levels of lithium than younger patients. The renal clearance of lithium decreases with age, increasing the elimination half-life and predisposing to lithium toxicity.⁹⁴ Neurotoxicity can develop at serum levels that are therapeutic in younger adults.⁹⁴ Frequently reported side effects of lithium include tremor, muscle twitches, GI symptoms, and CNS effects such as sedation.⁹⁴ Many common medications interact with lithium, including thiazide diuretics, nonsteroidal anti-inflammatory agents, and angiotensin-converting enzyme inhibitors, which can increase serum lithium concentrations and the risk of toxicity.⁹⁴ An older patient taking lithium can display signs of toxicity even if the level is in the therapeutic window. See chapter 181, "Lithium," for further details of toxicity and treatment. Three anticonvulsants have also been approved to treat bipolar disorder: valproate, carbamazepine, and lamotrigine. The literature regarding their use in older adults is sparse.⁸⁹

PSYCHOSIS (SCHIZOPHRENIA)

Several disorders, such as schizophrenia, psychosis associated with dementias, and more acute processes such as delirium, can present with symptoms of psychosis (hallucinations and delusions) in geriatric patients. This section provides a brief discussion of schizophrenia in older adults (please see earlier discussion regarding delirium and behavioral disturbances in dementia).

The estimated prevalence rate of schizophrenia in geriatric patients ranges from 0.1% to 0.5%.^95,96,97 The majority of patients with schizophrenia develop the disease in the second or third decade of life (considered early-onset schizophrenia), meaning that most geriatric patients with schizophrenia have had the disorder since they were much younger.⁹⁸ There are two other groups of patients with schizophrenia: late-onset schizophrenia (>40 years old) and very-late-onset schizophrenia-like psychosis (>60 years old).⁹⁸ Individuals with late-onset schizophrenia have many of the same attributes as patients with early-onset schizophrenia, but late-onset patients have fewer problems with learning, abstraction, and flexibility.⁹⁹ The diagnosis of very-late-onset schizophrenia-like psychosis is rare, but patients >60 years old can develop a late-life primary psychosis disorder.⁹⁸ Very-late-onset patients tend to have a lack of negative symptoms, greater risk of tardive dyskinesia, and evidence of a neurodegenerative process rather than a neurodevelopmental process.⁹⁸

Schizophrenia in geriatric patients represents complexity in the psychiatric, medical, and social realms. Nonadherence to medical therapy is common.¹⁰⁰ Mortality secondary to cardiovascular disease is more than twice as common as in the general population, likely due to high rates of smoking, diabetes mellitus, hypertension, and obesity in schizophrenic patients. Older patients with schizophrenia typically have a sedentary lifestyle and poor diet.¹⁰⁰ Atypical antipsychotics used for treatment increase the risk of metabolic syndrome and weight gain, which in turn increase the risk of cardiovascular diseases.¹⁰¹ The use of typical antipsychotics is limited because the risk of tardive dyskinesia is elevated in geriatric patients.¹⁰² One study noted that the cumulative annual incidence of tardive dyskinesia in patients >45 years old treated with low-dose typical antipsychotics was 26%, which is five to six times greater than in younger patients.¹⁰² Antipsychotic medications should be carefully selected and doses titrated upward slowly with close monitoring for side effects. Older patients with schizophrenia can also benefit from adjunctive psychosocial interventions. For example, Functional Adaptation Skills Training, a group therapy targeting everyday life skills, improves the functional adaptation of older patients with schizophrenia.^103,104,105

EATING DISORDERS

There is little information regarding eating disorders such as anorexia nervosa and bulimia nervosa in older adults. One recent study examined women >50 years old for the presence of eating disorders and found that about 13% reported some form of core current eating disorder symptoms. Current binge eating, and purging in the absence of binge eating, were the most common symptoms.¹⁰⁶ Approximately 71% of women in the study were currently trying to lose weight.¹⁰⁶ Another review identified 48 cases of eating disorders in adults >50 years old. In this article, 88% were female and 60% were >65 years old. The most frequent diagnosis was anorexia nervosa (81% of cases).¹⁰⁷ Of the 48 cases, 79% had the onset of eating disorders later in life.¹⁰⁷ Importantly, this study identified a strong connection between eating disorders and other psychiatric conditions (60% of cases), with major depression being the most important. Eating disorders were often preceded by a stressful event, such as widowhood, bereavement, and marriage difficulties.¹⁰⁷ Of the 48 patients reviewed, 21% of the patients died from complications of the eating disorder.¹⁰⁷

Diagnosis is difficult and is made by excluding any physical or medical cause of unexplained weight loss. Eating disorders in older patients are treated similarly to those in any other age group, with a combination of cognitive-behavioral treatment and pharmacotherapy.¹⁰⁷

Acknowledgments: Special thanks to members of the Academy of Geriatric Emergency Medicine, Dr. Timothy Platts-Mills, and Dr. Debra Bynum for their contributions to this chapter.