ESSENTIAL DIAGNOSIS
Progressive decline of intellectual function.
Loss of short-term memory and at least one other cognitive deficit.
Deficit severe enough to cause impairment of function.
Not delirious.
Loss of short-term memory and at least one other cognitive deficit.
Deficit severe enough to cause impairment of function.
Not delirious.
General Considerations
Dementia is an acquired persistent and progressive impairment in intellectual function, with compromise of memory and at least one other cognitive domain, most commonly aphasia (typically, word finding difficulty), apraxia (inability o perform motor tasks, such as cutting a loaf of bread, despite intact motor function), agnosia (inability to recognize objects), and impaired executive function (poor abstraction, mental flexibility, planning, and judgment). The diagnosis of dementia requires a significant decline in function that is severe enough to interfere with work or social life.
Dementia has a prevalence that doubles every 5 years in the older population, reaching 30–50% at age 85. Women suffer disproportionately, both as patients and as caregivers. Alzheimer disease accounts for roughly two-thirds of dementia cases in the United States, with vascular dementia (either alone or combined with Alzheimer disease) and dementia with Lewy bodies accounting for much of the rest. Some of the risk factors for Alzheimer disease are older age, family history, lower education level, and female sex. Education, cognitive “exercises,” and social support may be protective. Risk factors for vascular dementia are those for stroke, ie, older age, hypertension, cigarette use, atrial fibrillation, diabetes mellitus, and hyperlipidemia.
Depression and delirium are also common in elders, may coexist with dementia, and may also present with cognitive impairment. Depression is a common concomitant of early dementia. A patient with depression and cognitive impairment whose intellectual function improves with treatment of the mood disorder has an almost fivefold greater risk of suffering irreversible dementia later in life. Delirium, characterized by acute confusion, occurs much more commonly in patients with underlying
dementia.
dementia.
Clinical Findings
A. Screening
1. Cognitive impairment—Although there is no consensus at present on whether older patients should be screened for dementia, the benefits of early detection include identification of potentially reversible causes, planning for the future (including discussing values and completing advance care directives), and providing support and counseling for the caregiver.
The combination of a clock drawing task with a threeitem word recall (also known as the “mini-cog”) is a simple screening test that is fairly quick to administer. While different methods for administering and scoring the clock draw test have been described, the authors of this chapter favor the approach of pre-drawing a four inch circle on a sheet of paper and instructing the patient to “draw a clock” with the time set at 10 minutes after 11. Scores are classified as normal, almost normal, or abnormal. When a patient is able to draw a clock normally and can remember all 3 objects, dementia is unlikely. When a patient fails this simple screen, further cognitive evaluation with a standardized instrument is warranted. The Montreal Cognitive Assessment (MoCA ©) is a 30-point test that takes about 10 minutes to administer and examines several areas of cognitive function. A score below 26 is considered abnormal. Free downloadable versions in multiple languages are available at http://www
.mocatest.org.
.mocatest.org.
2. Decision-making capacity—Cognitively impaired elders commonly face serious medical decisions, and the clinicians involved in their care must ascertain whether the capacity exists to make the choice. While no single test of capacity exists, the following five elements should be considered in a thorough assessment: (1) ability to express a choice; (2) understanding relevant information about the risks and benefits of planned therapy and the alternatives, in the context of one’s values, including no treatment; (3) comprehension of the problem and its consequences; (4) ability to reason; and (5) consistency. A patient’s choice should follow from an understanding of the consequences.
Sensitivity must be used in applying these five components to people of various cultural backgrounds. Decisionmaking capacity varies over time: A delirious patient may regain his capacity after an infection is treated, and so reassessments are often appropriate. Furthermore, the capacity to make a decision is a function of the decision in question. A woman with mild dementia may lack the capacity to consent to coronary artery bypass grafting yet retain the capacity to designate a surrogate decision maker.
B. Symptoms and Signs
The clinician can gather important information about the type of dementia that may be present by asking about: (1) the rate of progression of the deficits as well as their nature (including any personality or behavioral change); (2) the presence of other neurologic symptoms, particularly motor problems; (3) risk factors for HIV; (4) family history of dementia; and (5) medications, with particular attention to recent changes.
Work-up is directed at identifying any potentially reversible causes of dementia. However, such cases are indeed rare. For a detailed description of the symptoms and signs of different forms of dementia, see Chapter 24.
C. Physical Examination
The neurologic examination emphasizes assessment of mental status but should also include evaluation for sensory deficits, possible previous strokes, parkinsonism, or peripheral neuropathy. The remainder of the physical examination should focus on identifying comorbid conditions that may aggravate the individual’s disability. For a detailed description of the neuropsychological assessment,
see Chapter 24.
see Chapter 24.
D. Laboratory Findings
Laboratory studies should include a complete blood count, electrolytes, calcium, creatinine, glucose, thyroid-stimulating hormone (TSH), and vitamin B12 levels. While hypothyroidism or vitamin B12 deficiency may contribute to the cognitive impairment, treating these conditions typically does not completely reverse the dementia. HIV testing, RPR (rapid plasma reagin) test, heavy metal screen, and liver biochemical tests may be informative in selected patients but should not be considered part of routine testing. For a detailed description of laboratory findings, see Chapter 24.
E. Imaging
Most patients should receive neuroimaging as part of the diagnostic work-up to rule out subdural hematoma, tumor, previous stroke, and hydrocephalus (usually normal pressure). Those who are younger and those who have focal neurologic symptoms or signs, seizures, gait abnormalities, and an acute or subacute onset are most likely to yield positive findings and most likely to benefit from MRI scanning. n older patients with a more classic picture oflzheimer disease in whom neuroimaging is desired, a noncontrast CT scan is sufficient. For a detailed description of imaging, see Chapter 24.
Differential Diagnosis
Older individuals experience occasional difficulty retrieving items from memory (usually manifested as wordfinding complaints) and experience a slowing in their rate of information processing. Mild cognitive impairment is an increasingly recognized condition in which a patient complains of memory problems, demonstrates mild deficits (most commonly in short-term memory) on formal testing, but does not meet criteria for dementia. Dementia will develop in more than half of people with mild cognitive impairment within 5 years. Acetylcholinesterase inhibitors have not consistently demonstrated a delay in the progression of mild cognitive impairment to Alzheimer disease. An elderly patient with intact cognition but with severe impairments in vision or hearing commonly becomes confused in an unfamiliar medical setting and consequently may be falsely labeled as demented. Cognitive testing is best performed after optimal correction of the sensory deficits.
Delirium can be distinguished from dementia by its acute onset, fluctuating course, and deficits in attention rather than memory. Because delirium and dementia often coexist, it may not be possible to determine how much impairment is attributable to each condition until the patient is fully recovered and back in their usual setting. Many medications have been associated with delirium and other types of cognitive impairment in older patients. Anticholinergic agents, hypnotics, neuroleptics, opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), antihistamines (including H1 and H2-antagonists), and corticosteroids are just some of the medications that have been associated with cognitive impairment in elders.
Treatment
Patients and families should be made aware of the Alzheimer’s Association (http://www.alz.org) as well as the wealth of helpful community and online resources and publications available. Caregiver support, education, and counseling can prevent or delay nursing home placement. Education should include the manifestations and natural history of dementia as well as the availability of local support services such as respite care. Even under the best of circumstances, caregiver stress can be substantial. Collaborative care models and disease management programs appear to improve the quality of care for patients with dementia.
Cognitive Impairment
Because demented patients have greatly diminished cognitive reserve, they are at high risk for experiencing acute cognitive or functional decline in the setting of new medical illness. Consequently, fragile cognitive status may be best maintained by ensuring that comorbid diseases such as congestive heart failure and infections are detected and treated.
1. Acetylcholinesterase inhibitors—Many experts recommendconsidering a trial of acetylcholinesterase inhibitors (eg, donepezil, galantamine, rivastigmine) in most patients with mild to moderate Alzheimer disease. These medications produce a modest improvement in cognitive function that is not likely to be detected in routine clinical encounters. Acetylcholinesterase inhibitors may also have similarly modest cognitive benefits in patients with vascular dementia or dementia with Lewy bodies. However, acetylcholinesterase inhibitors have not convincingly been shown to delay institutionalization or functional decline.
Starting doses, respectively, of donepezil, galantamine, and rivastigmine, are 5 mg orally once daily (maximum 10 mg once daily), 4 mg orally twice daily (maximum 12 mg twice daily), and 1.5 mg orally twice daily (maximum 6 mg twice daily). The doses are increased gradually as tolerated. The most bothersome side effects include diarrhea, nausea, anorexia, weight loss, and syncope. In those patients who have had no apparent benefit, experience side effects, or for whom the financial outlay is a burden, the drug should be discontinued.
2. Memantine—In clinical trials, patients with more advanced disease have been shown to have statistical benefit from the use of memantine, an N-methyl-d-aspartate (NMDA) antagonist, with or without concomitant use of an acetylcholinesterase inhibitor. Long-term and meaningful functional outcomes have yet to be demonstrated.
B. Behavioral Problems
1. Nonpharmacologic approaches—Behavioral problems in demented patients are often best managed with a nonpharmacologic approach. Initially, it should be established that the problem is not unrecognized delirium, pain, urinary obstruction, or fecal impaction. It also helps to inquire whether the caregiver or institutional staff can tolerate the behavior, as it is often easier to find ways to accommodate to the behavior than to modify it. If not, the caregiver should keep a brief log in which the behavior is described along with antecedent events and consequences. Recurring precipitants of the behavior are often found to be present or it may be that the behavior is rewarded—for example, by increased attention. Caregivers are taught to use simple language when communicating with the patient, to break down activities into simple component tasks, and to use a “distract, not confront” approach when the patient seems disturbed by a troublesome issue. Additional steps to address behavioral problems include providing structure and routine, discontinuing all medications except those considered absolutely necessary, and correcting, if possible, sensory deficits.
2. Pharmacologic approaches—There is no clear consensus about pharmacologic approaches to treatment of behavioral problems in patients who have not benefited from nonpharmacologic therapies. The target symptoms— depression, anxiety, psychosis, mood lability, or pain—may suggest which class of medications might be most helpful in a given patient. Patients with depressive symptoms may show improvement with antidepressant therapy. Patients with dementia with Lewy bodies have shown clinically significant improvement in behavioral symptoms when treated with rivastigmine (3–6 mg orally twice daily).
For those with Alzheimer disease and agitation, no agents have demonstrated consistent efficacy. Despite the lack of strong evidence, antipsychotic medications have remained a mainstay for the treatment of behavioral disturbances, largely because of the lack of alternatives. The newer atypical antipsychotic agents (risperidone, olanzapine, quetiapine, aripiprazole, clozapine, ziprasidone) are reported to be better tolerated than older agents but should be avoided in patients with vascular risk factors due to an increased risk of stroke; they can cause weight gain and are also associated with hyperglycemia in diabetic patients and are considerably more expensive. Both typical and atypical antipsychotics n several short-term trials and one long-term trial have been demonstrated to increase mortality compared with placebo when used to treat elderly demented patients with behavioral disturbances. When the choice is made to use these agents, patients and caregivers should be carefully warned of the risks. Starting and target dosages should be much lower than those used in schizophrenia (eg, haloperidol, 0.5–2 mg orally; risperidone, 0.25–2 mg orally). Federal regulations require that if antipsychotic agents are used in treatment of a nursing home patient, drug reduction efforts must be made at least every 6 months.
C. Driving
A common yet vexing problem that providers are regularly asked to assess is whether a patient with dementia is able to continue driving. The consequences of a decision to either stop or continue driving can be far-reaching for both the patient and the general public and therefore every case requires careful consideration. Although drivers with dementia are at an increased risk for motor vehicle accidents, many patients continue to drive safely well beyond the time of diagnosis, making the timing of when to recommend that a patient stop driving particularly challenging.
There is no clear-cut evidence to suggest a single best approach to determining an individual patient’s risk, and there is no accepted “gold standard” test. The result is that clinicians must consider several factors upon which to base their judgment. For example, determining the severity of dementia can be useful. Patients with very mild or mild dementia according to the Clinical Dementia Rating Scale were able to pass formal road tests at rates of 88% and 69%, respectively. Experts agree that patients with moderately severe or more advanced dementia should be counseled to stop driving. Although not well studied, clinicians should also consider the effects of comorbid conditions and medications and the role each may play in contributing to the risk of driving by a patient with dementia. Assessment of the ability to carry out IADLs may also add to the determination of risk. Caregivers of patients with at least a 30% decline in their IADL score were more likely to rate them as unable to drive safely than other, less impaired patients. Finally, in some cases of mild dementia, referral may be needed to a driver rehabilitation specialist for evaluation. Although not standardized, this evaluation often consists of both off- and on-road testing. The cost for this assessment can be substantial, and it is typically not covered by health insurance. Experts recommend such an evaluation for patients with mild dementia, for those with dementia for whom new impairment in driving skills is observed, and for those with significant deficits in cognitive domains such as attention, executive function, and visuospatial skills. At present, there is no convincing evidence to support the use of interventions to improve driving skills and driver safety.
Clinicians must also be aware of the reporting requirements in their individual jurisdictions. Some states have Starting doses, respectively, of donepezil, galantamine, and rivastigmine, are 5 mg orally once daily (maximum 10 mg once daily), 4 mg orally twice daily (maximum 12 mg twice daily), and 1.5 mg orally twice daily (maximum 6 mg twice daily). The doses are increased gradually as tolerated. The most bothersome side effects include diarrhea, nausea, anorexia, weight loss, and syncope. In those patients who have had no apparent benefit, experience side effects, or for whom the financial outlay is a burden, the drug should be discontinued.
2. Memantine—In clinical trials, patients with more advanced disease have been shown to have statistical benefit from the use of memantine, an N-methyl-d-aspartate (NMDA) antagonist, with or without concomitant use of an acetylcholinesterase inhibitor. Long-term and meaningful functional outcomes have yet to be demonstrated.
B. Behavioral Problems
1. Nonpharmacologic approaches—Behavioral problems in demented patients are often best managed with a nonpharmacologic approach. Initially, it should be established that the problem is not unrecognized delirium, pain, urinary obstruction, or fecal impaction. It also helps to inquire whether the caregiver or institutional staff can tolerate the behavior, as it is often easier to find ways to accommodate to the behavior than to modify it. If not, the caregiver should keep a brief log in which the behavior is described along with antecedent events and consequences. Recurring precipitants of the behavior are often found to be present or it may be that the behavior is rewarded—for example, by increased attention. Caregivers are taught to use simple language when communicating with the patient, to break down activities into simple component tasks, and to use a “distract, not confront” approach when the patient seems disturbed by a troublesome issue. Additional steps to address behavioral problems include providing structure and routine, discontinuing all medications except those considered absolutely necessary, and correcting, if possible, sensory deficits.
2. Pharmacologic approaches—There is no clear consensus about pharmacologic approaches to treatment of behavioral problems in patients who have not benefitedfrom nonpharmacologic therapies. The target symptoms— depression, anxiety, psychosis, mood lability, or pain—may suggest which class of medications might be most helpful in a given patient. Patients with depressive symptoms may show improvement with antidepressant therapy. Patients with dementia with Lewy bodies have shown clinically significant improvement in behavioral symptoms whentreated with rivastigmine (3–6 mg orally twice daily).
For those with Alzheimer disease and agitation, no agents have demonstrated consistent efficacy. Despite the lack of strong evidence, antipsychotic medications have remained a mainstay for the treatment of behavioral disturbances, largely because of the lack of alternatives. The newer atypical antipsychotic agents (risperidone, olanzapine, quetiapine, aripiprazole, clozapine, ziprasidone) are reported to be better tolerated than older agents but should be avoided in patients with vascular risk factors due to an increased risk of stroke; they can cause weight gain and are also associated with hyperglycemia in diabetic patients and are considerably more expensive. Both typical and atypical antipsychotics n several short-term trials and one long-term trial have been demonstrated to increase mortality compared with placebo when used to treat elderly demented patients with behavioral disturbances. When the choice is made to use these agents, patients and caregivers should be carefully warned of the risks. Starting and target dosages should be much lower than those used in schizophrenia (eg, haloperidol, 0.5–2 mg orally; risperidone, 0.25–2 mg orally). Federal regulations require that if antipsychotic agents are used in treatment of a nursing home patient, drug reduction efforts must be made at least every 6 months.
C. Driving
A common yet vexing problem that providers are regularly asked to assess is whether a patient with dementia is able to continue driving. The consequences of a decision to either stop or continue driving can be far-reaching for both the patient and the general public and therefore every case requires careful consideration. Although drivers with dementia are at an increased risk for motor vehicle accidents, many patients continue to drive safely well beyond the time of diagnosis, making the timing of when to recommend that a patient stop driving particularly challenging.
There is no clear-cut evidence to suggest a single bestapproach to determining an individual patient’s risk, and there is no accepted “gold standard” test. The result is that clinicians must consider several factors upon which to base their judgment. For example, determining the severity of dementia can be useful. Patients with very mild or mild dementia according to the Clinical Dementia Rating Scale were able to pass formal road tests at rates of 88% and 69%, respectively. Experts agree that patients with moderately severe or more advanced dementia should be counseled to stop driving. Although not well studied, clinicians should also consider the effects of comorbid conditions and medications and the role each may play in contributing to the risk of driving by a patient with dementia. Assessment of the ability to carry out IADLs may also add to the determination of risk. Caregivers of patients with at least a 30% ecline in their IADL score were more likely to rate them as unable to drive safely than other, less impaired patients. Finally, in some cases of mild dementia, referral may be needed to a driver rehabilitation specialist for evaluation. Although not standardized, this evaluation often consists of both off- and on-road testing. The cost for this assessment can be substantial, and it is typically not covered by health insurance. Experts recommend such an evaluation for patients with mild dementia, for those with dementiafor whom new impairment in driving skills is observed, and for those with significant deficits in cognitive domains such as attention, executive function, and visuospatial skills. At present, there is no convincing evidence to support the use of interventions to improve driving skills and driver safety.
Clinicians must also be aware of the reporting requirements in their individual jurisdictions. Some states have mandatory reporting laws for clinicians, but in other states, the decision to report an unsafe driver with dementia is voluntary. When a clinician has made the decision to report an unsafe driver to the Department of Motor Vehicles, he or she must consider the impact as a potential breach in confidentiality and must weigh and address, in advance when possible, the consequences from the loss of driving independence.
D. Advance Financial Planning
Difficulty in managing financial affairs often develops early in the course of dementia. The patient’s caregiver may seek advice from the patient’s primary care clinician. Although expertise is not expected, clinicians should have some proficiency to address financial concerns. Just as clinicians counsel patients and families about advance care planning, the same should be done to educate about
the need for advance financial planning and to recommend that patients complete a durable power of attorney for finance matters (DPOAF) when the capacity to do sostill exists. In most states the DPOAF can be executed with or without the aid of an attorney. Other options to assist in managing and monitoring finances include online banking, automatic bill payments, direct deposits andjoint bank accounts. A potential risk of the joint account is that the joint account holder has no obligation to act in the best interest of the patient.
the need for advance financial planning and to recommend that patients complete a durable power of attorney for finance matters (DPOAF) when the capacity to do sostill exists. In most states the DPOAF can be executed with or without the aid of an attorney. Other options to assist in managing and monitoring finances include online banking, automatic bill payments, direct deposits andjoint bank accounts. A potential risk of the joint account is that the joint account holder has no obligation to act in the best interest of the patient.
No gold standard test is available to identify when a patient with dementia no longer has financial capacity. However, the clinician should be on the lookout for signs that a patient is either at risk for or actually experiencing financial incapacity. Because financial impairment can occur when dementia is mild, making that diagnosis should alone be enough to warrant further investigation. Questioning patients and caregivers about late, missed or repeated bill payments, unusual or uncharacteristic purchases or gifts, overdrawn bank accounts and reports of missing funds can provide evidence of suspected financial impairment. Patients with dementia are also at increased risk for becoming victims of financial abuse and some answers to these same questions might also be signs of potential financial abuse. When financial abuse is suspected, clinicians should be aware of the reporting requirements in their local jurisdictions.
Prognosis
Life expectancy after a diagnosis of Alzheimer disease is typically3–15 years; it may be shorter than previously reported. Other neurodegenerative dementias, such as dementia with Lewy bodies, show more rapid decline. Hospice is often appropriate for patients with end-stage dementia.
When to Refer
Referral for neuropsychological testing may be helpful in the following circumstances: to distinguish dementia from depression, to diagnose dementia in persons of very poor education or very high premorbid intellect, and to aid diagnosis when impairment is mild.
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