Case #1 Answers:
The differential diagnosis for an eighty one year old man with increasing forgetfulness includes benign senescent forgetfulness, dementia, delirium, and depression. The history is most suggestive of a dementing illness given the slow time course, the difficulties in multiple tasks, the lack of evidence for depression and the results of the MMSE. Delirium is unlikely given the slow onset and course over two year as well as Mr. Ryan’s ability to maintain attention on the MMSE. Benign senescent forgetfulness is a mildly controversial entity that describes older individuals with isolated problems in memory. It is not progressive and should not interfere with functional status. Mr. Ryan denies the screening questions associated with depression and does not appear sad.
On the basis of the history and physical examination, it seems likely that Mr. Ryan is suffering from a senile dementia of the Alzheimer’s type. This is a diagnosis of exclusion and it will be important with the laboratory testing to rule out any surprises like hypothyroidism, but given the absence of a history of hypertension, cardiovascular disease, previous neurologic events, and the non-focal neuro exam it makes vascular dementia less likely.
Appropriate laboratory studies include a CBC with differential, a chemistry panel (glucose, lytes, BUN, Cre, LFT’s, Calcium), a TSH, and consider obtaining a B12, folate and RPR. Given the decreased vibratory sense, it is reasonable to obtain the B12 as well as the RPR. A hard question to answer is whether or not to obtain some type of neuroimaging study like a CT scan or MRI. Given that Mr. Ryan’s symptoms have been going on for two years, the chances of a reversible cause being found are less likely. I would obtain a CT scan without contrast, however, to rule out the possibility of a subdural hematoma, a frontal meningioma, or any other surprises.
Another finding on the physical exam is a hard prostate nodule. This is likely prostate cancer. It is unclear whether working this up and treating, either with surgery or radiation, would provide benefit for Mr. Ryan.
Students who are interested in the costs and benefits of a workup of cognitive decline can be referred to Siu AL. Screening for dementia and investigating its causes. Annals of Internal Medicine 1991;122-132.
I would ask Mr. Ryan if he had any questions about his condition or what the tests have shown. If he does not, I would tell him that I have concerns about his memory and that he may need further assistance in the future. I would also discuss with his family the likely diagnosis of Alzheimer’s disease, suggest that they review financial planning such as will and durable power of attorney with Mr. Ryan, discuss the need for advance directives for health care and durable power of attorney for health care, and urge them to consider some planning for the future as Mr. Ryan’s dementia progresses. This would include the need for further help in the home, the possibility of adult day care, and, perhaps, nursing home placement. In addition, the family should consider safety issues such as getting Mr. Ryan a name bracelet in case he wanders and being ready to disable the stove if he becomes forgetful and leaves it on. If Mr. Ryan is driving a car, this needs to end. The family should be notified to contact the Secretary of State and have his license revoked. The issue of physician notification of the State is difficult: I would suggest that the risk management office be called for advice in individual situations.
The family may benefit from a referral to a social worker to discuss some of the issues in planning as well as considering personal support in dealing with Mr. Ryan.
Should Mr. Ryan be told directly that he likely has Alzheimer’s disease? If he asks, then yes, provided that he can receive appropriate support with such a devastating diagnosis. It may be paternalistic, but I do not think it obligatory to volunteer the diagnosis to an individual who is unconcerned or unlikely to remember, especially as we currently lack clearly effective therapy. Others may disagree with this approach, feeling compelled to inform fully all patients of their diagnosis. It would be worth asking the students how they feel about this issue and how they would justify their position.