Friday, April 29, 2016
Cognitive Awareness Tests and Aricept
My mother has been on a trial of Aricept for 3 months. She was due for a cognitive test to see if she had responded to the drug but her appointments have been cancelled twice and it will be 2 weeks until her test is to take place. Would this affect the results of the test seeing she hasn`t taken the drug for 15 days? I just want the best chance for my Mum. Can you let me know if this delay would make a difference. Thanking you in advance.
In my opinion, Aricept and other similar medications used for Alzheimer's disease should only be used if the patient is willing to take them for at least 1 year. Otherwise the patient might as well be throwing their money away. Most brief cognitive tests of the type given in doctor's offices are not sensitive enough as a general rule to see a significant effect from these medications in much less than a year.
Very detailed neuropsychological testing can pick up changes usually in 3 months. However, if a brief test is used after 3 months, it is likely not to show much change from the natural history of the disease. For example if the Mini-Mental State Examination (MMSE) is used, patient's who fall in the category of mild to moderately severe Alzheimer's disease, would decline an average of 3 points a year untreated. Therefore the average rate of decline untreated after 3 months is less than a point. This is within the error of the test. A patient can have a 1 to 2 point difference in their test scores if they take the test 5 minutes later. Therefore you could test her again but I would not use the test scores after 3 months to decide on treatment continuation or not.
If after one year she is less than three points down on the MMSE, then she is doing better than the average and it would suggest a positive benefit of the drug. Over 80% of patients on Aricept and similar agents do better than the natural history of the disease after one year. In fact the greatest benefit of these drugs is usually seen after 3-5 years. These are long term treatments. Aricept will be out of her system in about 15 days and so it is a waste of time to test her if she has not been on the medication continually.
Douglas W Scharre, MD
Clinical Associate Professor of Neurology
Clinical Associate Professor of Psychiatry
College of Medicine
The Ohio State University