Tuesday, December 15, 2009

Psychological/Psychiatric Evaluation to Diagnose Alzheimer’s Disease

Psychological evaluation represents the collection of the specific targeted procedures that are used to obtain detailed information about past and current mood, thinking, or behavioral problems. The person with suspected Alzheimer's symptoms and the primary caregiver should be interviewed separately in order to gain a complete picture of what is going on. This "double interview" technique is particularly important when a person's memory for past and present information is impaired, because he or she may inadvertently provide inaccurate information during the interview. This evaluation should include an assessment for anxiety and depression, which can create Alzheimer's-like symptoms in older people, as well as occur concurrently with Alzheimer's or another form of dementia. Depression, in particular, can result in a reversible set of symptoms collectively known as pseudo-dementia.
Image and video hosting by TinyPic

The following tests may be used in a psychological/psychiatric evaluation:

The Geriatric Depression Scale (GDS) - The GDS is a screening instrument used to detect depression among older adults. Clinicians may use it to help determine whether someone is depressed (and doesn't have AD), or if depression coexists with Alzheimer's or another form of dementia. Results from the GDS are interpreted in the context of the other information collected about the person. For example, people with depression often complains about memory problems and is upset about them, while individuals with dementia will often deny memory problems or minimize their importance. Also, depressed people are less likely to exhibit large mood swings, remaining "down in the dumps" most of the time (except when they have bipolar disorder, a shift in moods from extreme highs to extreme lows). On the other hand, people with dementia usually show a range of emotions, and sometimes respond with an inappropriate emotion (e.g., laughing while others are sad). If a mood disorder such as depression is detected, it can be treated alongside other disorders, such as Alzheimer's. Generally speaking, high scores on the GDS suggest that people are experiencing depressive symptoms.

Image and video hosting by TinyPic

Mental status exam - Mental status exams assess memory, concentration, and other cognitive skills. The most frequently used mental status exam is called the Mini-Mental State Exam (MMSE), a research-based set of questions that results in a score representing a person's general level of cognitive functioning.

The MMSE is generally a reliable and valid indicator of cognitive impairment that can correctly distinguish between individuals with dementia, individuals with pseudo-dementia due to depression, and individuals with depression and no cognitive impairment. However, the test must be used with caution in certain groups of people. For example, highly educated people frequently score high on the MMSE, even if they have Alzheimer's Disease. Similarly, people with less than an eighth grade education or whose first language is not English often score poorly on the MMSE, even though they may not have cognitive impairment.

The MMSE takes only 5 - 10 minutes to administer and taps five areas of cognitive functioning:


Ask the patient what (year) (season) (date) (day) (month) it is (5 Points).
Ask the patient where he/she is (province) (country) (town or city) (hospital) (floor) (5 Points).


Name 3 common objects (e.g., “apple”, “table”, “penny”). Take 1 second to pronounce each word. Then ask the patient to repeat all 3 words. Give one point for each correct answer. Then repeat them until he/she learns all 3. Make a maximum of 6 trials (3 Points).


Ask the patient to subtract 7 from 100 and keep subtracting 7 until you tell him/her to stop. (93, 86, 79, 72, 65)


Ask him/her to spell “WORLD” backwards. The score is the number of letters in correct order (D_L_R_O_W) (5 Points).


Ask the patient for the 3 objects repeated above. Give 1 point for each correct answer. (Note: Recall cannot be tested if all 3 objects were not remembered during registration.) (3 Points).


Show the patient a “pencil” and a “watch” and ask him/her to name them (2 Points).
Ask your patient to repeat the following: « No ifs, ands or buts. » (1 Point).
Ask your patient to follow a 3-stage command: « Take a paper in your right hand, fold it in half, and put it on the floor. » (3 Points).
Ask the patient to read and obey the following:
- Close your eyes. (1 Point).
- Write a sentence. (1 Point).
- Copy the following design. (1 Point).

The maximum score on the MMSE is 30. In general, scores of 24 or more are considered within the "normal" range of cognitive functioning; scores between 20 and 23 are suggestive of mild cognitive impairment or possible early-stage Alzheimer's Disease; scores between 10 and 19 are associated with middle-stage Alzheimer's; and a score of 9 or less is considered consistent with severe or late-stage Alzheimer's Disease.

While the test has wide acceptance, one weakness is that the examiner must interpret responses, a subjective process. Different examiners might score the same response differently, and local adaptations can affect comparisons. Internal consistency and test-retest validity have been reported from 0.68 to 0.95.

Although the MMSE is a useful screening tool, test results should not be the only information used to make a diagnosis. In other words, a person's MMSE score can indicate a need for concern, and additional testing and follow-up.

Sources and Additional Information:
Related Posts Plugin for WordPress, Blogger...