AAN Guideline Update on Mild Cognitive Impairment: A Co-Author Shares Takeaways

For the first time since 2001, the American Academy of Neurology (AAN) has updated its practice guideline on mild cognitive impairment (MCI). The guideline update, which was published in Neurology at the end of December, made headlines for including the AAN’s first-ever recommendation that exercise may help improve memory and cognition in people with MCI.

Cleveland Clinic neurologist Alexander Rae-Grant, MD, served as primary facilitator for the update process as part of the AAN’s Guidelines Committee and participated on the panel that wrote the guideline update, which has been endorsed by the Alzheimer’s Association.

Consult QD interviewed Dr. Rae-Grant to learn more about the guideline process and highlights of the new recommendations.

Q: Why did the AAN decide to update its MCI guideline now?

A: The real question may be why we didn’t update it sooner, since the last update was 16 years ago. The reason is twofold. First, the process takes quite a while — at least two years from start to finish. Second, we wanted to include findings of randomized trials of cholinesterase inhibitors, and many of those results weren’t available at the time of the prior guideline.

Q: What methodology was used?

A: The process is well-defined and updated yearly. The Guidelines Committee, of which I’ve been a member for several years, commits to doing a guideline on a specific topic. We put together a panel of experts in the field, and the panel defines questions to ask about the topic. A systematic review is performed and the evidence is classified as high confidence, moderate confidence, low confidence or very low confidence, depending on the data available and the panel’s assessment of various factors that may raise or lower confidence in it. Then the panel meets to discuss the recommendations that can be made from the systematic review process and based on principles of care. Recommendations are designated ultimately by strength as Level A (strongest), Level B (moderate) or Level C (weak). The panel votes on each recommendation and finalizes the language for the recommendation and its supporting rationale. The recommendations are then sent out to the public and the journal for comment before being finalized.

Q: What types of MCI did the update focus on?

A: We looked at idiopathic or neurodegenerative MCI related to Alzheimer’s disease. These are patients who have some kind of measurable cognitive problem, usually memory impairment. They and/or their family members are usually aware of the problem, but it typically doesn’t affect their daily function. However, MCI does put them at higher risk for developing dementia over the next few years. We excluded MCI related to potentially reversible causes such as metabolic, vascular, systemic or psychiatric disorders, Parkinson’s disease or vascular cognitive impairments.

Q: The big news from this update seems to be the first-ever AAN recommendation for exercise to combat MCI. How much exercise is recommended, and what kinds?

A: We evaluated two Class II, six-month studies of the impact of exercise on MCI. These were randomized trials with some limitations due to their methodology, and this evidence yielded a Level B recommendation. These trials suggest that exercising twice a week using a combination of aerobic activity and resistance training may be beneficial for improving cognition, and particularly memory, in this condition. Of course, regular physical exercise has benefits for the heart and general health while carrying few risks, so it’s a good overall health strategy to encourage.

Q: The guideline says clinicians may choose not to prescribe cholinesterase inhibitors for patients diagnosed with MCI. How did that recommendation come about?

A: There are a number of fairly large clinical trials that don’t support the use of cholinesterase inhibitors in this population. However, the panelists were concerned that there may be person-to-person variations in response, meaning some patients with MCI might benefit from these drugs. The panel wanted to craft language to give clinicians leeway to not use these drugs or, if they want to prescribe them, to encourage counseling patients that this is an off-label use with a lack of supportive evidence.

Q: What’s recommended in terms of cognitive training?

A: Because we had only weak evidence to go on, we made a Level C recommendation that cognitive interventions may be helpful in improving function in people with MCI.

In my own practice, rather than recommending that patients do computer brain games or crossword puzzles, I tell them it appears that activities that engage the mind — making art or playing music, for instance — and involve social interactions may be the most beneficial interventions. But this is not a finding of the guideline panel.

Q: Were you able to make any dietary recommendations?

A: No. There have been no high-quality, long-term dietary intervention studies for MCI. However, as with exercise, we know that what’s best for overall health — moderation in portions, healthful food types, etc. — is likely to be best for MCI as well.

Q: What are the key takeaways from this guideline update for practicing neurologists and geriatricians?

A: We hope they will take seriously the importance of testing and counseling patients who have symptoms of MCI and are at risk for developing dementia. The panel recommends that clinicians look for modifiable conditions or medication side effects that, once managed, can improve cognition. We also hope that clinicians will let patients know about research trials they can join. Since no pharmacologic or dietary agents have yet been proven beneficial, we need to build a stronger medical armamentarium for MCI.