ABSTRACT: Older individuals are at risk for adverse events in all settings where cancer is treated. Common geriatric syndromes can complicate cancer therapy, and thus, increase patient morbidity and the costs of care. Furthermore, cancer treatment can worsen geriatric syndromes. It is often difficult to determine whether declining health is a result of cancer treatment or the patient’s underlying disease. Baseline assessment of multiple factors may facilitate detection of a decline in the patient’s health status, which may be remediable. Geriatric syndromes may substantially affect quality of life and are also important in the prognosis and outcome of cancer therapy. This article reviews the assessment of cognitive syndromes (dementia and delirium), vision and hearing impairment, gait and balance difficulties, malnutrition, incontinence, depression, osteoporosis, sleep disorders, environmental and social issues, and functional decline. Although there are many geriatric domains and many focused assessment tools, assessment does not need to be time-consuming. Streamlined assessment tools have been developed; they are brief, inexpensive, and easily administered, and they may be valuable to the oncologist. Staff such as nurses, social workers, or office personnel could perform these assessments and minimize the impact on the physician’s time. [ONCOLOGY 15:1567-1591, 2001]
Despite recent advances in geriatric care, the elderly remain at risk for adverse events in all settings where cancer is treated. Common geriatric syndromes such as delirium, gait imbalance, malnutrition, and incontinence can complicate cancer therapy, and thus, increase patient morbidity and the costs of care. Furthermore, cancer treatment can worsen geriatric syndromes. Chemotherapy can affect cognition, function balance, vision, hearing, continence, and mood. It is often difficult to determine whether declining health status is a result of cancer treatment or the patient’s underlying disease. Baseline assessment of multiple factors may facilitate detection of a decline in health status, which may be remediable.
The role of the oncologist may also include the provision of primary care. Many cancer patients see their oncologist for primary care issues. As the population of older Americans dramatically increases, the oncologist will likely need to assume some of the responsibilities of a primary-care physician or geriatrician. Because geriatric syndromes may substantially affect quality of life, oncologists will need to be comfortable with assessing and addressing geriatric syndromes. Many of these syndromes (eg, cognition and function decline) are also important in determining prognosis and outcome in cancer therapy.
This article will review the assessment of cognitive syndromes (dementia and delirium), vision and hearing impairment, gait and balance difficulties, malnutrition, incontinence, depression, osteoporosis, sleep disorders, environmental and social issues, and functional decline. The goal of this review is to recognize the importance and relevance of these geriatric syndromes in the care of elderly cancer patients and to understand the assessment instruments available to screen for these syndromes.
In older patients, the two most important cognitive problems are dementia and delirium.
Dementia is defined as a significant decline in two or more areas of cognitive functioning. Most people with dementia (60% to 70%) have Alzheimer’s disease (which affects 4 million Americans). Vascular dementia (15% to 25%) and mixed dementia (10% to 15%) are the next most common types of the disease. Other types include dementia with Lewy bodies, frontal-temporal dementia, dementia associated with Parkinson’s disease, and pseudodementia, a dementia-like syndrome that occurs in conditions (eg, depression) with no pathologic features of dementia.
The most important risk factors for Alzheimer’s disease are age and family history. Other factors include head trauma, depression, and Down syndrome. Recently, a variation in the apolipoprotein E gene has been identified as a risk factor. Of the three alleles (APOE 2, 3, and 4), the APOE 4 allele increases risk, whereas the APOE 2 allele is thought to be protective.
Delirium is defined as a disturbance of consciousness with decreased ability to focus that develops over a short period of time and fluctuates. It is often associated with changes in cognition and perceptual—classically, visual—disturbances.
The prevalence of delirium among patients over the age of 65 years presenting to the emergency room ranges from 10% to 24%. Among hospitalized older patients, prevalence ranges from 25% to 60% and is a predictor of poor prognosis, with the risk of short-term mortality increased 2- to 20-fold.[4,5] However, when controlling for age and severity of disease (both of which are risk factors for delirium), delirium is not an independent risk factor in long-term mortality.
Delirium in hospitalized patients is also frequently persistent. It only resolves completely by the time of discharge in a small portion (4%) of patients, within 3 months in 21%, and within 6 months in 18%.[6,7] Although most patients improve over time, some older patients retain persistent features of delirium.
Risk factors for delirium include preexisting dementia, severe medical illness, alcohol(Drug information on alcohol) abuse, diminished functional ability, depression, and hearing or visual impairment. A diagnosis of dementia or psychiatric disorder, such as psychosis, should not be made during delirium.
Dementia vs Delirium
It is often difficult to distinguish dementia from delirium, but there are several important differences. In delirium, symptoms develop over a few hours, whereas in dementia, they develop insidiously. In delirium, impairment of attention is a central feature, but in dementia, attention is relatively preserved until the late stages of the disease. Moreover, in delirium but not in dementia, the patient’s level of consciousness typically fluctuates. In addition, speech is often incoherent in patients with delirium but usually both coherent and ordered in patients with dementia.
Cognitive impairment in cancer patients often goes unrecognized. Cognitive function and capacity are important issues to consider in decision-making with older patients. The prognosis of dementia patients depends on the mental and physical state of both the patient and caregiver. Given the impact of dementia on prognosis and quality of life, oncologists should take into account the level of cognitive function when deciding whether to pursue aggressive cancer therapy in the demented older person.
Older cancer patients must either have the capacity to provide informed consent or must delegate decision-making to a proxy. A diagnosis of dementia per se does not mean an inability to give informed consent. However, a careful assessment of competency may be necessary in a patient with dementia to demonstrate that consent is truly "informed." Nevertheless, most patients with delirium will not be able to give consent. Furthermore, as the patient’s underlying cancer progresses or complications of treatment develop, the older patient may become unable to make health-care decisions. Therefore, issues regarding resuscitation status and potential levels of treatment should be discussed early in the course of cancer care and revisited if the patient’s disease progresses.
Dementia can develop secondary to cancer treatment. Dementia has been reported following radiotherapy of brain tumors when administered either alone or in combination with nitrosurea-based chemotherapy. More often, however, chemotherapy predisposes the patient to delirium. For example, older patients have been shown to have more cognitive deficits after postoperative adjuvant chemotherapy for breast cancer. In addition, many cancer patients undergoing chemotherapy are at risk for infection (with or without neutropenia), dehydration, electrolyte disorders (especially hyponatremia), and malnutrition, either directly from the tumor or as a side effect of the chemotherapy. These patients are at high risk of developing delirium.
Assessing Cognitive Function
A first step in the evaluation of mental function in the elderly may be assessment with the Mini-Mental Status Exam (MMSE). The MMSE is a 30-point scale that evaluates time and place orientation, registration, attention, calculation, naming, repetition, comprehension, reading, writing, and drawing (Table 1). Although performance on this exam may be affected by age and education, a score of 24 or less suggests cognitive dysfunction for most people.
A commonly used screening test for delirium is the Confusion Assessment Method. The criteria and algorithm for this assessment evaluate four features associated with delirium:
1. Acute onset and fluctuating course—Is there evidence of an acute change in mental status from the patient’s baseline? Did the (abnormal) behavior fluctuate during the past day, ie, tend to come and go or increase and decrease in severity?
2. Inattention—Does the patient have difficulty focusing attention, eg, is she or he easily distractible, or having difficulty keeping track of what is said?
3. Disorganized thinking—Is the patient’s speech disorganized or incoherent, manifesting as rambling or irrelevant conversation, an unclear or illogical flow of ideas, or unpredictable switching from subject to subject?
4. Altered level of consciousness—How would you rate the patient’s level of consciousness? Alert (normal), vigilant (hyperalert), lethargic (drowsy), stuporous (difficult to arouse), or comatose (unarousable)? For this feature, any answer other than alert is abnormal.
A positive test for delirium requires an abnormal rating for questions 1 and 2, and either 3 or 4.
The prevalence of visual impairment, defined as a visual acuity of 20/40 or worse, is 4% to 5% among persons over age 65 years and 10% to 21% among those over age 75. In 36% of older persons with visual impairment, the cause is cataracts; in 14%, macular degeneration; in 7%, diabetic retinopathy; and in 5%, glaucoma. The leading cause of blindness among African-Americans is cataracts, whereas for Caucasians, it is macular degeneration.
Cancer treatment of an older patient with visual impairment poses additional risks beyond the normal complications of chemotherapy. First, many chemotherapy regimens and underlying malignancies can cause symptoms of fatigue, dizziness, and peripheral neuropathy, which, combined with visual impairment, can greatly increase the risk of falling. Furthermore, the morbidity (eg, hip fractures) and mortality associated with falling may be greater among patients with low platelet counts, bleeding disorders, or bony metastasis. Compliance with dosing schedules may also be hindered if the patient lives alone and cannot see well enough to read labels.
Testing Visual Acuity
Screening for visual impairment can be performed by using a Snellen chart or instruments such as the Activities of Daily Vision Scale (ADVS). Visual disability may not be captured by routine visual testing, but the ADVS has proven to be a reliable and valid measure of such impairment. The ADVS focuses on five subscales: distance vision, near vision, glare disability, night driving, and daytime driving. Far vision tasks that are evaluated with the ADVS include reading signs, use of transportation, and walking up steps. Near vision tasks include items such as watching television, reading medication bottles, writing checks, and using threads and needles or rulers and screwdrivers.