Overview

About this study

Dementia is a disease that causes a person to lose their memory, speech, and thinking skills. People with heart disease are at high risk of brain function decline, that can lead to dementia. Reduced blood flow to the brain can cause this decline in brain function. Factors linked with heart disease (such as poor blood vessel function and low fitness level) also lead to reduced brain blood flow. Exercise training can improve these factors. However, it is unknown what type of training is best for improving brain blood flow and function.

High intensity interval training (HIIT) is a type of training where bouts at a hard effort (cannot talk while breathing), alternate with bouts at a low effort. Moderate intensity training (MICT) is a type of training at a medium effort (can talk while breathing) that can usually be done without stopping. In people with heart disease, HIIT has been shown to double fitness and blood vessel function compared to MICT. As a result, we believe that HIIT will be better than MICT for increasing brain blood flow and brain function in these patients. To answer this, we will study people with heart disease after a heart event and use specialized tests to measure their brain blood flow and function. We will randomly assign patients to HIIT or MICT during a heart rehab program. Some patients also choose not to participate in the heart rehab program. After 12 weeks we will repeat the tests, to see whether exercise training improves brain blood flow and function, and whether HIIT or MICT lead to greater improvements. We will also study people without heart disease to assess what level of brain blood flow and function is normal for their age, to compare against our patients. We will also assess other factors about our patients that could help identify a low level of brain blood flow or function.

There are 47 million people in the world that have dementia. About 30% of these cases are linked to heart disease. This study will help us better understand brain blood flow and brain function in people with heart disease. It will help assess the amount of impairment caused by a heart event and heart disease. This study will also help identify types of patients, that are more likely to have low levels of brain blood flow and function. This could lead to a risk calculator for doctors, to identify patients that need additional tests or monitoring. The study will also determine if exercise during a heart rehab program can improve brain blood flow and function, and whether HIIT or MICT is better. This could allow for a targeted program to improve or maintain brain health; and reduce the risk of dementia.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Participating Mayo Clinic locations

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