|By Harvard Medical School, October 9, 2019
The journey toward a diagnosis of MCI is most often initiated by a person's subjective complaint about memory and thinking problems or by concerns expressed by those closest to the individual. This is an important distinction because cognitive changes that are readily apparent to the broader outside world are more likely to signal that the person is suffering from dementia. In addition, people who have progressed into Alzheimer's disease are often not aware of their memory lapses. The primary objective of the evaluation should be to distinguish MCI from normal aging or dementia and to look for underlying causes that are potentially reversible. Establishing the cause and scope of the impairment is helpful in setting a baseline for future evaluations to determine if the condition is progressing to dementia.
Although your regular doctor is a good place to start the process because he or she knows you and your medical history, most primary care physicians don't have the time or training to thoroughly evaluate MCI. Instead, look for a doctor who focuses on cognitive function, such as a behavioral neurologist or a geriatric psychiatrist. Your local Alzheimer's Association chapter, medical school, or hospital can help direct you to an appropriate specialist.
Before evaluating your cognitive health, your doctor will look for clues that your memory problems may be a symptom of an underlying health problem. To help explore this possibility, the physician will frequently order a complete blood count and blood chemistry tests to detect anemia, infection, diabetes, and kidney and liver disorders. Other lab work will include routine tests for thyroid function, vitamin B12 deficiency, and elevated blood calcium. If the physician suspects a specific medical problem, additional tests may be needed. Your doctor will also want to review all the medications you take, to see if any of these drugs may be causing cognitive symptoms.
The physician will pay close attention to the nervous system because abnormalities in muscle strength, coordination, reflexes, senses, eye movement, and the pupils' reaction to light can signal abnormalities in specific areas of the brain. For example, unequal reflexes or weakness on one side of the body suggests localized brain damage that could be caused by stroke or a tumor. On the other hand, tremors or other involuntary movements may indicate a degenerative disorder such as Parkinson's disease. Because the doctor will also want to test vision and hearing.
Cognitive function evaluation
The doctor will start this evaluation with a detailed history of your cognitive changes over time. It is important for someone who knows you well and is familiar with your medical history, current symptoms, and concerns to be present to help corroborate your recollections. Certain features in your history can be telling. For example, cognitive decline that takes place rapidly— over weeks or months—is not typical of changes in brain structure involved in MCI or Alzheimer's disease. Instead it may indicate a problem such as a tumor or metabolic irregularity.
You may be referred to a psychologist with specialized training in brain disorders for comprehensive neuropsychological tests. These tests may take the form of interviews, paper-and-pencil tests, or computer-based tests. The tests are designed to assess memory, reasoning, attention, language, visual functions, motor functions, and social functions (such as empathy and knowing how to behave appropriately in social situations). You may also be given other tests to identify depression, anxiety, and other mood problems.
Structural brain scans
A brain scan using either computed tomography (CT) or magnetic resonance imaging (MRI) may be done to examine the anatomic structure of the brain. These scans are used to rule out such problems as tumor, infection, bleeding, stroke, and hydrocephalus (excess fluid in the area around the brain). Brain scans can also reveal evidence of blockages in the brain's small blood vessels and tissue damage that indicate vascular dementia. These scans can also show the loss of brain mass associated with Alzheimer's disease and other degenerative dementias.
Sometimes additional testing may be suggested. These tests tend to be expensive and may not be covered by your health insurance.
Functional brain imaging
A type of brain scan called fluorodeoxyglucose positron emission tomography, or FDG-PET, identifies regions of lower brain activity based on the amount of glucose used in the area. People who show decreased glucose use in their temporal or parietal lobes may be at higher risk for MCI that may progress into dementia.
Similarly, single-photon emission computed tomography (SPECT) scanning assesses blood flow within the brain to gauge brain activity. Because blood flow is greater in very active portions of the brain, diminished blood flow to certain areas can indicate the presence of degeneration.
Amyloid PET scans
Scientists have developed new techniques that allow them to detect in the living brain the presence of amyloid plaques, the hallmark of neurodegenerative diseases like Alzheimer's. Amyloid plaques are tangles of proteins that aggregate and stick to one another in the brain, leading to the disruption of cellular structure and eventually cell death. To confirm the presence of amyloid plaques, one technique involves PET scans that use chemical tracers, which bind specifically to amyloid deposits, allowing them to show up clearly on brain scans. The type of amyloid PET scan most widely available is called a florbetapir PET scan.
Cerebrospinal fluid (CSF) biomarkers
Cerebrospinal fluid is a clear liquid that surrounds and cushions the brain and spinal cord. Changes in the levels of beta-amyloid and tau proteins in CSF indicate brain changes that occur with Alzheimer's disease. For people with MCI, the presence of these substances can be a signal of the progression to dementia.
Your memories of the past. Your dreams for the future. Your ability to recall, reason, and think. It’s all in that three-pound organ between your ears—your brain. With so much at stake, protecting your brain from cognitive decline should be your highest health priority.
Understanding Mild Cognitive Impairment is here to help. The new guide from the experts at Harvard Medical School, is your indispensable handbook to understanding mild cognitive impairment (MCI), reducing its impact, and possibly preventing it from happening at all.
Yes, sometimes cognitive impairment is *reversible*
As you’ll learn in the guide, some types of MCI are reversible. For example, certain medications may cause reactions that mimic cognitive decline. Memory and other cognitive functions may be restored simply by changing medications. Or a person may have experienced a head injury, resulting in localized bleeding called a subdural hematoma. This can lead to changes in memory loss and thinking. If the blood is removed within weeks of the injury, memory function may recover. As the guide makes clear, be sure to consider all potential causes of MCI before assuming you can’t get your cognitive abilities back to where they were.
Shielding your brain against MCI
Understanding Mild Cognitive Impairment reveals how you can take action to prevent or minimize MCI. You’ll learn, for example, how getting enough sleep, exercising regularly, and lowering your stress levels can all boost your cognitive function. Giving your brain a workout through education and with mental challenges like puzzles and games can help, too. In addition, the guide explains how a traditional Mediterranean diet can lower the risk of MCI and slow the progression of dementia in people who have the condition.
The latest MCI treatment options
A lot of research is going on to find a drug treatment for MCI, but as of now there’s no medication or supplement that’s been proven effective. However, as the guide explains, there are other options. For example, cognitive training, in person or via computer, can help people with MCI develop their remaining cognitive skills. Another option is to improve cardiovascular fitness—for instance, by lowering blood pressure, reducing cholesterol, and quitting smoking. This can reduce the chance of a blood vessel becoming blocked and causing brain damage.
Get to know the fundamentals of MCI
Understanding Mild Cognitive Impairment gives you the information you need to approach MCI with confidence. The guide offers an overview of the brain’s different areas and explains how memories are created and stored. In easy-to-understand language, you’ll learn how MCI is different from dementia conditions like Alzheimer’s. You’ll also read about the risk factors for MCI, such as age, genetics, cardiovascular fitness, and depression, and how MCI is diagnosed.
There’s still more to discover in Understanding Mild Cognitive Impairment, including: five key indicators of memory-related MCI • the differences between memory-related MCI and MCI that affects other functions of the brain • an overview of the six cognitive domains, such as memory, language, and attention • how brain function changes with normal aging vs. MCI and dementia • how spending time with friends and family can do wonders for your brain health • and more!
To learn more about MCI, read the online guide from Harvard Medical School, Understanding Mild Cognitive Impairment.