Ethical Foundations of Palliative Care for Alzheimer Disease

THREE: The Clinical Challenge of Uncertain Diagnosis and Prognosis in Patients with Dementia

mc h a  t e r t h r e e The Clinical Challenge of Uncertain Diagnosis and Prognosis in Patients with Dementia David A. Bennahum, M.D. Alzheimer disease (AD) is most often thought of by the general public as being characterized by memory loss. But most humans experience a loss of memory with illness or old age, and in my years as a clinician I have learned that it can be difficult to distinguish a dementia from common agerelated forgetfulness, although recent research would suggest that the latter might predict future disease. I have also found that as the number of people with dementias increases, clinicians must become more and more skilled in distinguishing among the different types. Dementia, described by Brumback in the preceding chapter, can be the result of more than fifty-five conditions, among them Huntington disease, vitamin B12 deficiency and pernicious anemia, hypothyroidism , Parkinson disease, Pick disease, syphilis, AIDS, arteriosclerosis, strokes, Down syndrome, and, of course, Alzheimer disease. Most of these conditions affect memory, behavior, and overall health. The dementia associated with them, if untreated, or inappropriately treated, can result in premature death. In this chapter, I provide the reader with some typical cases that a clinician might see and then briefly summarize the most common conditions that result in dementia by distinguishing the presenting symptoms, how each diagnosis is made, whether predictive genetic testing is now available, treatment, and what is known about the physiologic basis of each disease. It is noteworthy that the diagnosis and prognosis for a patient may depend more on the clinical experience and acumen of the physician than on any particular test or procedure. Discovery of the genes that correlate with Alzheimer and Huntington diseases have improved not only the physician’s diagnostic ability but also may make it possible to predict the probability of disease in a patient’s children and other relatives. Recently, positron emission tomography (PET) scanning has been suggested as a potentially accurate tool for the diagnosis of AD, but further corroboration still is required. m Aging and Dementia Confusion and loss of memory are increasingly common as people age (Byrne, 1994). The prevalence of dementia increases with age: “It occurs primarily late in life; the prevalence is about 1% at the age of 60 and it doubles every five years, to reach 30% to 50% by the age of 85” (Geldmacher & Whitehouse, 1996, p. 330). By the age of sixty-five, 2 to 3 percent of the population in the industrialized world have probable AD—a percentage as noted above that doubles every five years thereafter. At age seventy-five, between 12 and 14 percent have AD, and at age eighty the probability of AD is closer to 25 percent. After age eighty-five,somewhere between one-third and one-half of all individuals may be affected (Post, 2000). Alzheimer disease “affects over 4 million people in the United States, resulting in over 100,000 deaths per year and costing the nation more than $60 billion annually”(Martin, 1999, p. 1970). It is predicted that the number of persons with dementia will rise throughout the world. As population growth declines in both the developed and the underdeveloped world, the problem of caring for so many fragile elders will become enormous. m Assessing Patients Who Are Confused In any geriatric practice, one sees many patients who have memory loss and are confused and disoriented. It is equally important to recognize and respond to the fears and needs of families and caregivers. The following are typical examples. 48 Health Care Challenge of Alzheimer Disease Case 1. A seventy-five-year-old retired physician is brought to the clinic by his wife. He looks well and states that he feels fine and that he has not noticed any loss of memory. His wife states that he has trouble accomplishing simple tasks such as shopping at the supermarket and that, the week before, he became lost while driving. On the Folstein Mini-Mental State Examination (see table 2.1), the patient scores 22 out of a possible 30. The normal range is 25 to 30 (Folstein, 1975). When asked to draw a clock, he places all the numbers on one side. The rest of the history and the physical examination are normal. The patient is not anemic, he has normal B12 and thyroid tests, and an MRI (magnetic...