A Guide to the Diagnosis and Assessment of Alzheimer's Disease

A case study in AD:  presentation, diagnosis and management

During her annual physical, breast and pelvic exam, you discuss family issues with Barbara, 47, a patient for many years. You ask after her mother Thelma, whom you have not seen in some time. Barbara reminds you that her father died just three years ago and is concerned about Thelma, living on her own, as she seems to have "given up". "She is just not interested in anything, and doesn't bother to feed herself. I really think she is losing her mind since Dad died". Thelma is 79.

• Time is short. You are already behind schedule.
• What three direct questions will give you the most information at this point?
• What are the diagnostic possibilities?
• What should your next step be for Thelma?

You ask three specific questions: how long has this self-neglect and lack of interest been going on? How abruptly did it start? Is it getting progressively worse?

The changes have been very slow, and are getting progressively worse, Barbara tells you. Thelma's memory is not good. She recently forgot that they had been out shopping the previous day, and she missed her hairdresser's appointment. She recently got lost driving in a familiar place, calling Barbara in a tearful panic from a pay telephone. Nothing like this had happened before.

• Are these symptoms related to the bereavement?
• Does this fit the profile of 'normal bereavement'?
• Is a depressive illness a possibility?
• What should you do next?

You tell Barbara firmly that you must see her mother. Although many people become less functional when bereaved, it should not last this long. You are concerned that she is getting worse. Barbara is surprised, feeling this to be a normal reaction for an older person. She agrees to contact her mother, who adamantly refuses to attend your office. "There is nothing wrong with me," she says.

• Do you need to pursue this patient, despite her unwillingness?
• What dangers exist for her and for others in her current situation?
• Might she be medically ill, and need treatment?
• How would you currently advise her daughter?

You advise Barbara that should any medical excuse at all come up, trivial or not, you will see Thelma. You advise her to try to observe her mother's driving, nutrition, and access to alcohol or medications, and to involve her in their family life, to observe her, despite her unwillingness and denial.

PART 5

Several months later, Barbara is requesting an acute office visit for Thelma, following a fall. Thelma has requested to come, concerned about a cut to the head. Although busy, you agree to see her and treat her, with plans to include a cognitive assessment.

• Time is short: could your nurse assist in this assessment?
• What are the minimum baseline questions?
• What further investigations should be done, now or later?
• Is there any special advice for the daughter before collecting her mother?

You ask your nurse to contact Barbara to advise her to bring all her mother's medications with her. Your nurse conducts an MMSE and a CDT along with a full set of vital signs including orthostatic blood pressures and blood tests on Thelma, using the head injury as an excuse. Barbara is asked to complete an FAQ.

• If she will consent to a blood test, what should be included?
• Is she in danger from her head injury?

Her head laceration is slight and treated easily. Her MMSE score is just 14/30, with significant problems in memory, orientation to time, visuospatial skills (word reversal, pentagon) but not language. Her daughter is astonished that her mother believes it is 1969. The FAQ score is 18.

Medications available to Thelma include three different OTC sleep aids, all antihistamines. Physical examination, although necessarily brief, confirms no lateralizing or localizing signs, gait is normal and confident and turning and balancing is quite satisfactory. There is no orthostatic change in BP and vital signs are normal. Laboratory tests include a thyroid screen, B₁₂, folate, albumin, CBC, ALT, ESR, BUN/creatinine and electrolytes.

You persuade her that she needs an "X-ray of her head". You obtain a CT scan, which shows marked temporoparietal atrophy, with no sign of vascular abnormalities, subdural hematoma or other space-occupying lesion.

In your brief interview with her, you ask about memory loss, which she denies. She denies problems with sleeping. Biological symptoms of depression, such as early morning mood disorder (diurnal variation), early morning waking, appetite or weight change, or a sense of fatigue are all negative. In fact, Barbara reinforces that her mother seems quite inappropriately cheerful and satisfied with life, despite her memory impairment, and generally enjoys family visits. She continues to drive, and has had two minor accidents in the past two months. There appeared to have been no other falls.

• What important diagnoses have already been excluded from the differential diagnosis?
• What immediate action should be taken to prevent further impairment and danger?
• Is specific treatment available for the definite cognitive impairment?

This case demonstrates how proactive primary care physicians can access patients with dementia who would not otherwise be seen, or who would at least have had their investigation and care postponed. The frequent lack of awareness on the part of the patients, mandates a flexible, yet comprehensive approach. Patients often do not present until the symptoms are very well established.

It is never too late to look both for causes and for contributory factors. In this case, the potentially impairing medications need to be removed. Driving will need to be given up, in view of the accidents and visuospatial impairment. The family will need considerable support and advice in order to safely maintain this lady in her environment for as long as possible. This family was uninformed about dementia, initially accepting the changes as 'normal aging' or the result of bereavement.

Since the symptoms are extremely suggestive of dementia of Alzheimer's type (DAT) there is enough information to justify the use of specific pharmacologic treatments for AD, i.e. one of the currently available cholinesterase inhibitors to maintain and hopefully improve her cognitive status. As is the general rule for prescribing in older people, it will be important to have an easy medication to take, preferably once a day.

PART 8
Follow-up

Although there are some initial difficulties with compliance, she does become established on medication, and on follow-up her cognitive status actually improves a little, and she remains at a mild to moderate level of cognitive function. She is already impaired enough to potentially benefit from participation in a day program, to which she is persuaded to go on the basis that a meal will be provided, and that it will be something of a 'social club' to counteract her admitted loneliness since her husband died. Her family becomes involved with a local Alzheimer's Association, and soon after the diagnosis of AD is confirmed, they attend a brief course, and become informed about the illness.