Johns Hopkins Health Alert
Diagnosing Alzheimer's Disease
While there is still no cure for Alzheimer’s disease, early diagnosis offers many benefits. Johns Hopkins doctors review the current diagnostic tools available for dementia and Alzheimer’s disease.
If you’re worried about Alzheimer’s disease, the first step is to talk to your primary care physician about any symptoms you’ve been experiencing. Because diagnosing Alzheimer’s disease is primarily a process of elimination, your medical history and any recent health changes you’ve noticed might point to an explanation other than dementia. Your physician should screen you for depression, which can impair memory and cause anxiety, irritability and poor concentration.
Your physician should also inquire about any medications and dietary supplements you are taking: Are you taking the proper dosage? Are you on the right schedule? Has another physician recently prescribed a new drug or changed your dosage? Again, medications can have effects that mimic those of Alzheimer’s disease, and this possibility must be ruled out.
The Mini-Mental State Exam and other tests for Alzheimer’s disease
If your physician suspects Alzheimer’s disease, he or she may perform a test called the Mini-Mental State Exam (MMSE), a 17-item screening test that assesses general cognitive function and provides a single numerical score. A score of 24 or higher is considered normal. The MMSE is not a particularly sensitive test for Alzheimer’s disease. Scores can drift up or down according to educational level, cultural background, reading level and language skills.
Further testing may be needed at a separate office visit with a dementia specialist, such as a neurologist, geriatric psychiatrist, geriatrician, or neuropsychologist. The doctor will administer some tests by asking you questions; other tests require you to make drawings, solve special puzzles or answer questions in written form.
Depending on your symptoms, your doctor may order laboratory tests. Again, the purpose is to rule out causes other than Alzheimer’s disease, tightening the circle of diagnosis until it zeroes in on the probable cause. Blood tests can identify anemia, liver disorders, thyroid problems, nutritional deficiencies and infections.
In recent years, there has been a wave of news reports on the latest and greatest brain scanning techniques for the detection of early Alzheimer’s disease. These high-tech tests go by a variety of acronyms: MRI; fMRI; SPECT; PET; and CT. Of the imaging tests mentioned above, your doctor is most likely to consider a CT scan or MRI to check for physical brain abnormalities associated with Alzheimer’s disease, or to rule out some other cause of the symptoms. These brain scans may detect small strokes, which can cause problems in the brain’s blood supply and lead to vascular dementia.
So-called functional scans, such as positron emission tomography (PET), are increasingly being used in the diagnosis of Alzheimer’s disease. They reveal information about the level of activity (function) in various areas of the brain that might be affected by Alzheimer’s disease.
Posted in Memory on November 7, 2006
Reviewed June 2011
Medical Disclaimer: This information is not intended to substitute for the advice of a physician. Click here for additional information: Johns Hopkins Health Alerts Disclaimer
Notify Me
Would you like us to inform you when we post new Memory Health Alerts?
Comments
Health Alerts registered users may post comments and share experiences here at their own discretion. We regret that questions on individual health concerns to the Johns Hopkins editors cannot be answered in this space.
The views expressed here do not constitute medical advice, and do not represent the position of Johns Hopkins Medicine or Remedy Health Media, LLC, which has no responsibility for any comments posted on this site.
Post a Comment
Already a subscriber?
Login
New to Johns Hopkins Health Alerts?
