You’re worried. Memory lapses have become more frequent, and you find yourself frequendy confused about the day of the week, your whereabouts, and what you did just hours ago. A family history of Alzheimer’s has you wondering whether you have the disease. You call your doctor seeking help.
At the moment, diagnosing Alzheimer’s remains an imprecise science. Unlike many diseases which can be diagnosed by a marker in the blood or an X-ray, Alzheimer’s cannot be fully confirmed until autopsy, when the disease’s telltale plaques and tangles can be seen on the brain.
Instead, doctors rely on a combination of patient history— which includes observations by family members and close friends—and various exams, laboratory tests, and brain scans to determine whether someone has Alzheimer’s. Taken together, these tools allow a doctor to diagnose a patient with probable Alzheimer’s. The sum total of these diagnostic measures produce remarkable accuracy—90 percent of the time, doctors are right when they diagnose someone with Alzheimer’s.
If you’re concerned at all about your memory problems or those of a loved one, consider consulting a physician. Getting a proper diagnosis helps rule out other conditions that may mimic or resemble Alzheimer’s, conditions that are often treatable and reversible. It will also help you secure a diagnosis of early Alzheimer’s, which will give you the time to learn more about the disease, adapt, to having it, and plan for the day-to-day care you may need down the road.
Medical Evaluations
The following are some helpful tools and tests that a physician may use to determine whether you have Alzheimer’s:
Patient History
Most physicians will begin your evaluation by asking about your health history. To get the most accurate portrayal of your health and well-being, you should go to this appointment with a loved one, spouse, or close friend who can also add insight to your health history and provide information about personality changes that you, the patient, may not be aware of.
In addition to establishing basic information such as your age, your doctor will most likely want to know the following:
• Your symptoms. When did they begin? When did you first notice them? Are they getting worse with time? How are they affecting your day-to-day living?
• Other medical conditions you have.
• Your medical history.
• Your current health status.
• Over-the-counter and prescription medications you are taking as well as vitamins, supplements, and herbal remedies.
• Family history of dementia.
• Family and cultural background.
• Your daily routine. Do you work? Do you visit with friends? What are your hobbies and activities?
• Your mental well-being, which includes assessing for depression.
Physical Examination
The physical exam helps the doctor determine your overall health. The doctor will take your blood pressure, pulse, and tem¬perature, and also measure your height and weight. The physical exam helps the doctor rule out other medical conditions that may be causing cognitive problems such as hypothyroidism and congestive heart failure.
Blood and Urine Tests
As part of the process, your doctor may also ask for a sample of your blood and urine. These important laboratory tests can reveal infections, liver and kidney problems, diabetes, thyroid problems, and anemia. Certain conditions, such as megaloblastic anemia, which is caused by a vitamin B12 or folate deficiency, can be detected in the blood and may resemble dementia. Metabolic imbalances in the thyroid, liver, and kidneys can also cause symp¬toms of dementia.
Mental Status
Using a simple screening test called the Mini-Mental State Exam, the doctor will gauge your mental abilities, namely memory, language, and organizational skills. The test includes questions regarding your whereabouts and asks you to perform simple tasks. It measures and evaluates your ability to remem¬ber, understand, and communicate. A low score alone does not indicate you have Alzheimer’s or any other form of dementia, but simply suggests that you might.
Neurological Exam
Neurology refers to the study of the brain and nervous system. To get an idea of how well your brain and nerves are functioning, your doctor will check your reflexes, coordination, and motor skills. These exams may help determine what parts of the brain are affected. They can also help determine whether you may have other neurological disorders. Several conditions may resemble Alzheimer’s, and they will be discussed later in this chapter.
Lumbar Puncture
Examining the cerebrospinal fluid that supports the brain can pro¬vide information about the presence of other diseases. The proce¬dure, which is commonly called a spinal tap, involves inserting a needle into the fluid in die spinal canal. The fluid is removed and examined for conditions such as normal pressure hydrocephalus and brain tumors, conditions that can cause dementia, but which are both treatable.
Brain Scans
Modern science has made it possible for us to view the brain through different imaging technologies. In people with Alzheimer’s, shrinkage in some areas of the brain may be detected through the use of these techniques. There are four scans that are commonly used to determine whether someone has Alzheimer’s:
• CT scan, also called computerized tomography or CAT scan. Unlike X-rays that shoot two-dimensional images of a body part or organ, a CT scan rotates around the body so that images are gleaned from several angles. A computer then processes the information and produces a cross-section of the tissues.
• MRI, or magnetic resonance imaging. Using magnetic fields and radio waves, the MRI picks up small energy signals emitted by the atoms that comprise body tissue, then produces images of organs and structures in the body.
• PET, or positron emission tomography. A PET scan helps reveal which parts of the brain are working hardest dur¬ing particular mental activities. PET is a relatively new technique for detecting Alzheimer’s. Radioactive material is injected or inhaled into the body, and a camera follows the path of the substance as it settles into the organs. A computer then produces a three-dimensional view of the organ. In a person who has Alzheimer’s, a PET scan typi¬cally shows less brain activity than that which occurs in a healthy person.
• Single photon emission computed tomography (SPECT). Like the PET scan, SPECT involves injecting a small amount of a radioactive substance into the body. The more blood flow there is in a particular organ, such as the brain, the more the substance is taken up. The radioactive substance emits a special kind of energy called photons, which are then picked up by a rotating camera outside the body. The camera takes pictures of the brain activity, which are converted by computer into cross-sectional images and three-dimensional images.