The Mini-Mental State Examination, or MMSE, is the most commonly used screening test for Alzheimer's disease, according to the Fisher Center for Alzheimer's Research Foundation. It is not, however, the only mental status test available to a physician. Each screening test has its merits and limitations. In Alzheimer's disease, the neurodegenerative changes that occur in the brain result in complex mental impairment. Loss of memory, though likely the most widely recognized deficit, is not the only impairment a screening test reveals. As the Rush University Medical Center points out, "There is not a single, comprehensive test for diagnosing Alzheimer's disease." Regardless of which mental status test a doctor chooses, it conveys only a part of the picture.
Description
A mental status test provides general information about various spheres of cognition such as memory, concentration, language, counting, problem solving and abstract thinking. A screening test can also reveal how aware a patient is of cognitive and functional difficulties. Home screening tests are now widely available, but the Alzheimer's Association advises that these tests ". . . cannot and should not be used as a substitute for a thorough examination by a skilled doctor."
Standard Screens
The MMSE poses a series of questions and problems for the patient. A patient is asked, for example, to count backwards from 100 by sevens, to spell "world" backwards, to identify familiar objects and to make up and write a sentence that must contain a noun and a verb. The exam takes approximately seven to 10 minutes to administer. The maximum score is 30 points. The Alzheimer's Association explains the scores in this way: a score between 20 and 24 suggests mild dementia, a score between 13 and 20 suggests moderate dementia and a score of less than 12 indicates severe dementia. In some circumstances, the MMSE may require too much time to administer. Accuracy of the test may be affected by language fluency and level of education.
The Mini-Cognitive Assessment Instrument, or Mini-Cog, is briefer than the MMSE. It consists of two tasks. First, a patient is asked to remember and then recall later the names of three familiar objects. Second, a patient is instructed to draw a face of a clock with a given time. The test has the advantages of taking only minutes to administer and avoiding the language fluency problems encountered in the MMSE.
Other Screens
Other mental status tests are similar in format to and serve the same purpose as the MMSE and Mini-Cog.Tests such as the Memory Impairment Screen and the General Practitioner Assessment of Cognition take only minutes to administer. Like the Mini-Cog, they are well suited to the primary care setting. But both the MMSE and Mini-Cog have continued to maintain a high rank in studies comparing the efficacy of the various mental status tests.
Research
The need to find a mental status test that can predict Alzheimer's disease earlier has driven recent research. The Dana Foundation notes that neurologists at the Mayo Clinic and their colleagues at Penn State are using the Free and Cued Selective Reminding Test on participants in a study. The findings of the mental status test are entered into a statistical program and the data correlated with scans from high-resolution magnetic resonance imaging of the region of the brain affected by Alzheimer's disease.
Diagnosis
A definitive diagnosis of Alzheimer's disease is not possible without the confirmation of a postmortem examination of the brain. But, a physician can make a probable diagnosis with a high degree of accuracy by considering the findings of a mental status test in conjunction with the results obtained from a physical examination, neuropsychological testing, laboratory tests and brain imaging.
