Scared of Alzheimer Disease? Run From It

Medscape Cardiology 

Henry R. Black, MD

Apr 05, 2013

Hi. I am Dr. Henry Black, Clinical Professor of Internal Medicine at the New York University Langone Medical Center, former President of the American Society of Hypertension, and a member of the Center for the Prevention of Cardiovascular Disease at New York University.

One of the biggest problems we are facing now, and certainly in the future, is dementia and Alzheimer disease. It is estimated that by the time we reach our mid-80s, 15% of Americans will have that diagnosis, and the cost is well over $5 billion and likely to rise.

Everything that has been tried to reduce that risk has pretty much failed. Crossword puzzles do not help, and neither do foods or nutritional supplements. The one thing that seems to make some difference is exercise. This was evaluated very recently in an article in Annals of Internal Medicine from a group at the Cooper Institute in Dallas, Texas.^[1]

This group has been interested in the importance of exercise in cardiovascular disease assessment and prevention since 1970. They have been at it a long time and analyzed long-term effects of exercise in thousands and thousands of individuals, based on Medicare claims data. For this study, they carefully evaluated risk factors and exercise abilities with a standard protocol—how many metabolic equivalents (METs) they achieved and maximal oxygen consumption (VO₂), for example. Then they divided the groups into quintiles. The people in the highest quintile of fitness level were then compared with the people in the lowest quintile to see whether or not they developed Alzheimer disease.

The results are clear: Those in the highest quintile had a lower Alzheimer disease risk than those in the lowest quintile.

One problem with the study is the population they looked at. Almost all had a college education or more, almost all were white, and they were certainly in a higher socioeconomic stratum. How applicable is this to the general population?

Also important, however, is that they looked at midlife fitness -- not when patients were older but during midlife. The average age of the people they evaluated was about 50 years. What they found is clear: If you have a high level of fitness in your 40s, or maybe even earlier than that, your likelihood of developing Alzheimer disease later on is definitely reduced.

What is the take-home message? Don't wait until you have an event (people who had events previously were excluded); get yourself on the treadmill, put your running shoes on, row, whatever it is you want to do, but try to get your fitness level up high when you are in your 30s and 40s, because this is going to prevent you to some degree from having Alzheimer disease when you are in your 70s and 80s, or beyond, hopefully.