Major Mental Disorders of Older Adults
Major depression is common in community dwelling older adults (2–4%), and even more common in residents of long-term care facilities. Depressive symptoms are even more prevalent, affecting up to 20% of older adults. Chronic medical conditions are common in this population and increase the risk of developing depression. Major depression in geriatric patients manifests in all the usual ways seen in younger adults, but nonspecific and atypical symptoms are common and may dominate the clinical presentation. Although depressed mood and hopelessness have diagnostic value, less specific symptoms may be prominent and give valuable clues to the underlying diagnosis. Anhedonia, anxiety, fearfulness, irritability, cognitive impairment, apathy, dependency, and numerous somatic complaints should prompt the consideration of depression even when the patient denies feeling depressed (see Chapter 25).
The most efficient tool for assessing mood is the two-question screener: “In the past month, have you felt depressed or down?” and “In the past month have you had little interest or pleasure in activities and/or hobbies?” If either question is answered in the affirmative, further testing is indicated. The GDS is a more complete screening tool. Scores can be followed over time to monitor progression or response to therapies.
The prognosis for depression in old age is fairly good, at least for acute symptoms, and patients need to be told this to counter the hopelessness they might feel. However, partial remissions and relapses are common, especially in patients with previous episodes of depression. Other negative predictors include persistent health problems that compromise function or comfort, poor social support, and ongoing psychosocial stressors. Antidepressant medications have been shown to improve outcomes and reduce the risk of relapse in older adults. Caution must be used when prescribing antidepressants in older adults as side effects may outweigh any gains in mood. Electroconvulsive therapy (ECT) has high efficacy rates and can be used for drug-resistant depression, as well as patients with psychotic features. There are no absolute contraindications, but many patients experience short-term memory loss after this treatment.
Cognitive impairment associated with depression may improve with remission of the mood disorder, but is predictive of an underlying dementia. Such patients need close follow up to catch the dementia early and ensure safety at home. ACOVE has developed quality measures to help clinicians treat depression effectively. These include recognizing depression, screening for suicidality, treating depression, and monitoring for response to therapy.
Older patients have the highest per capita use of antianxiety medications. These figures are probably higher than necessary, since many of the anxious elderly are actually suffering from depression as their primary illness. Apart from depression, the differential diagnosis of anxiety in older adults includes transient apprehension and fear, adjustments to life changes, phobic avoidant behaviors, obsessive-compulsive disorder, panic disorder, posttraumatic stress, and generalized anxiety disorder (see Chapter 26). Secondary anxiety disorders are also very common: medications, chronic obstructive pulmonary disease, and endocrinopathies are often implicated.
Although the mainstay of pharmaco therapy for anxiety in all adults are selective serotonin reuptake inhibitors (SSRIs) many patients are treated with benzodiazepines. Unfortunately, due to physiologic changes of drug excretion as well as changes to the benzodiazepine receptors, older adults are exquisitely sensitive to this class of medications and often suffer adverse side effects. Increased somnolence, unsteadiness, memory loss, and disinhibition are common, and dangerous, reactions. If there is no other option for treatment, clinicians should opt for short-acting formulations in small doses. In patients with long-term use, a taper should be attempted.
Delusional thinking arises from a number of disturbances in old age. Hallucinations can be seen in end-stage dementia and delirium. Charles Bonnet syndrome is a condition that causes patients with vision loss to have complex visual hallucinations. These hallucinations are often not bothersome, and the patient frequently has insight that the visions are not real. Although there is no specific treatment for Charles Bonnet syndrome, fixing the visual deficit can stop the hallucinations. Musical hallucinosis is an auditory variant of hallucinosis associated with acquired deafness, in many ways analogous to Charles Bonnet syndrome. A primary delusional disorder of unknown etiology, previously known as paranoia, is sometimes seen in older women who live alone. Although these patients describe persecutory delusions of an intense nature, highly suggestive of schizophrenia, they do not have other manifestations of this disease, such as hallucinations, loose associations, disorganized behavior, and functional decline. Elders who do exhibit these cardinal symptoms of schizophrenia have usually had the disease for many years, although it can develop in late life. Paranoia and delusions can also be the presenting symptoms of dementia, depression, mania, and alcohol abuse.
The prevalence of dementia, or Major Neurocognitive Disorder per the DSM-V, increases with age, approaching 20% at the age of 80 years and 50% by the age of 90 years. The diagnosis of dementia is made when intellectual impairment is severe enough to affect independent functioning. Alzheimer disease (AD) is the most common cause of dementia in the elderly, and can be diagnosed with fairly good accuracy by using formal diagnostic criteria (see Chapter 30). The presence of progressive decline in recent memory, normal motor function (without weakness, ataxia, or parkinsonism), and deficits in at least one other higher cortical function (language, praxis, visual–spatial, calculations, and executive functions), is highly supportive of the diagnosis. Mild cognitive impairment (MCI) is diagnosed when cognition is impaired but function remains intact. Mild cognitive impairment, amnestic type, gradually progresses to AD in most individuals, while mild cognitive impairment of the non-amnestic type (often characterized by executive function deficits) may progress to vascular dementia or Lewy Body Dementia. Medical treatment of AD includes long-term maintenance on acetylcholinesterase inhibitors and memantine (for modest improvement in symptoms and slowing of functional decline) if the patient has shown a response, treatment of neuropsychiatric symptoms when necessary, and attention to comfort (especially pain), continence, and caregiver distress.
Many vitamins and supplements including vitamin E, vitamin B, and Gingko biloba have been suggested to slow the progression of the disease; but unfortunately, none has been shown to be effective in clinical trials. Vitamin E is associated with higher cardiovascular risk and for this reason, is not recommended. The best nonpharmacologic data for prevention of dementia and slowing of disease is the Mediterranean diet and a healthy exercise routine.
Prescribing atypical antipsychotic medications to treat agitation and psychosis in patients with dementia is complicated by clinical trial evidence of higher mortality risk (60–70% higher vs. placebo) and a Food and Drug Administration (FDA) warning against their use in this population. A multicenter trial funded by the National Institute on Aging indicates that the efficacy of these drugs is often limited by rapid discontinuation because of side effects. Nevertheless, the atypical antipsychotics remain in widespread clinical use, partly because of the high risk of the symptoms these drugs are used to treat, and also a relative lack of evidence for safety and efficacy of alternative medications. If used in this population, these medications should be dosed very conservatively, patients and families should be counseled on the risks, and patients should be closely monitored for side effects including sedation.
ACOVE has developed quality measures for dementia. These include screening all vulnerable elders for cognitive impairment and reviewing medication lists for possible causative therapies. They also recommend a thorough neurologic and laboratory examination in patients who screen positive for dementia. A discussion about the benefits of acetylcholinesterase inhibitors should be initiated in all patients, and a history of behavioral symptoms should be elicited. Lastly, clinicians should provide caregiver support, as burnout is common and can negatively impact both the patient and the family.
Another common dementia of older age is Dementia with Lewy Bodies (DLB). This is diagnosed when a patient manifests progressive dementia, parkinsonism (especially bradykinesia and rigidity without tremor), daily fluctuations in mental status similar to delirium, and visual hallucinations. Sleep disturbance is common, especially daytime sleepiness and excessive motor activity during rapid eye movement (REM) sleep. Dementia with Lewy Bodies accounts for 5–10% of cases of dementia, and may occur mixed with AD. Treatment of DLB involves a trial of acetylcholinesterase inhibitors and psychotropic medications for targeted neuropsychiatric symptoms. Older antipsychotic medications, such as haloperidol, must be rigorously avoided. Most clinicians will prescribe low doses of quetiapine (12.5–100 mg/day in divided doses) for delusions and hallucinations that do not respond to acetylcholinesterase inhibitors; however, this is considered off label use and the increased mortality risk noted in the black box warning does apply. For neuropsychiatric symptoms that persist after cholinesterase treatment within package insert dosing guidelines, there is some evidence that higher doses can be tolerated with improved efficacy. Parkinsonism can respond modestly to l-dopa, but l-dopa can worsen neuropsychiatric symptoms, and needs to be used with caution in patients with DLB.
Vascular dementia is another common cause of intellectual and functional decline in older adults, accounting for about 5% of dementia cases and contributing to worsening dementia in many more patients as a comorbid condition with AD. Large cortical strokes produce a stepwise decline with noticeable points of change associated with recurrent strokes. Small-vessel disease producing lacunar infarcts in subcortical structures is associated with hypertension and diabetes. Also known as Binswanger dementia, this condition produces a more gradually progressive dementia that looks similar to AD, but with more obvious gait impairment, incontinence, parkinsonism, and affect lability. Executive function and cognitive processing speed are usually affected more than memory. Circulatory problems in the absence of stroke (i.e., congestive heart failure, hyperviscosity states, and so forth) can also produce cognitive impairment. Patients with vascular dementia can potentially benefit from a trial of cholinesterase treatment.
Delirium is characterized by the acute (within hours) or subacute (within days) development of disorientation and confusion. Inability to focus and sustain attention are key to the diagnosis. Hallucinations, fearful or paranoid perceptions, fluctuating awareness, and alterations in the sleep–wake cycle are other frequent symptoms. In patients with mild delirium, the decreased level of alertness may not be obvious. Patients will often have psychomotor slowing, listlessness, and apathy. These patients may be misdiagnosed as depressed or demented, although there frequently is an underlying dementia. Delirium is often the first symptom of medical illness in frail elderly people. The most common causes of delirium in older patients are infections (usually urinary tract and pulmonary), medications, metabolic abnormalities, alcohol or sedative intoxication and withdrawal, stroke, seizures, and heart failure. In patients with dementia, problems such as pain, fecal impaction, and urinary retention can cause rapid changes in mental status and behavior that look like superimposed delirium.
Many, if not most, older adults have at least mild delirium when hospitalized for an acute illness or surgery. An excellent screening tool for delirium is the confusion assessment method, and this should be performed on every older adult at risk of delirium. In hospital settings, delirium increases fall rates, length of stay, and risk of poor outcomes. Adequate pain control and correction of metabolic problems or infections will help shorten the time course of the delirium. Agitation, paranoia, and sleeplessness may require separate pharmacologic management (see Chapter 30). Low doses of haloperidol (0.25–1 mg every 4 hours, max 4.5 mg daily) or quetiapine (12.5–25 mg up to 2–3 times daily) is the treatment of choice in most instances. Patients should be monitored closely for cardiovascular complications. Younger patients, or those with primary mental illness, may need higher doses or alternate therapies.
Substance Abuse and Polypharmacy
Often overlooked, substance abuse is common in older adults; alcohol abuse is the third most common mental disorder in older men. Unexplained falls, ataxia, confusion, malnutrition, burns, head trauma, and depression should prompt questions about surreptitious alcohol abuse. Prescription pain medication, sedative–hypnotic medications, over-the-counter remedies for constipation, sleeplessness, and pain; and numerous vitamins and supplements are also overused. Seeing multiple physicians and practitioners and patronizing several pharmacies are clues to the clinician that prescription abuse is likely (see Chapter 24). Polypharmacy increases the risk of adverse drug reactions, a leading cause of confusion, depression, falls, and functional decline. Frequent medication review and reduction should be part of the care of every older adult.
Geriatric patients are not immune to somatic perceptions for which there are no known physical causes. Of course, older patients often manifest illness in vague and nonspecific ways, so an open mind is necessary when thinking through mysterious symptoms. The clinician should avoid unnecessary interventions while continuously supporting the needs of the patient to be heard and understood. Although regularly scheduled appointments with brief, focused examinations that allow the “laying on of the hands” continue to be the most effective interventions, major depression and anxiety disorders commonly underlie somatization. Antidepressants and psychotherapy may improve function and a sense of well-being in somatically focused patients (see Chapter 28).