Heart health and brain volume are linked in a new study.
Successfully maintaining a healthy heart is known to significantly reduce the risk of developing a range of health conditions later in life. For this reason, a lot of effort goes into advising the public about the best ways of keeping the heart strong.
For instance, the American Heart Association has developed "Life's Simple 7," comprising seven steps to follow that can help people to ensure their own cardiovascular health. Life's Simple 7 consist of these factors:
- maintain a healthy blood pressure
- control cholesterol
- reduce blood sugar
- be active
- eat better
- lose weight
- stop smoking
Life's Simple 7 also have effects beyond the heart; research has shown that people who follow these seven guidelines are more likely to score better on cognitive tests.
For instance, a study published in 2013 found that maintaining good cardiovascular health from young adulthood to middle age was associated with "better psychomotor speed, executive function, and verbal memory in midlife."
Another paper, published in PLOS One in 2014, similarly concluded that better cardiovascular health was associated with "greater cognitive performance."
Life's Simple 7 and brain health
A group of researchers led by Michael Bancks, Ph.D., of Northwestern University Feinberg School of Medicine in Chicago, IL, recently set out to further test these findings. They wanted to see if following these steps produced measurable changes in the volume of brain tissue.
To investigate the links between heart health and brain health in later life, the researchers delved into data from the Coronary Artery Risk Development in Young Adults Study. In all, their study involved 518 people who had been followed for 30 years.
When the participants first joined the cohort, they were screened for weight, height, cholesterol, and blood pressure, and they were asked about their diet and exercise regimes. They also had follow-up examinations every 2 to 5 years and an MRI brain scan after 25 years. In the scan, they measured brain volume as a percentage of their total head size.
On each of the seven heart health parameters, the participants were given a score: they received zero for poor adherence, one for intermediate adherence, and two points for ideal. Overall, this produced a range of scores from 0 to 14 that were then split into categories. These were:
- 0-7: poor adherence
- 8-11: intermediate adherence
- 12-14: ideal adherence
At the start of the study, 5 percent were classed as having poor adherence, 62 percent as having intermediate, and 33 percent as having ideal. By the 25th year, 26 percent were scored as having poor adherence, 58 percent as having intermediate, and 16 percent as having ideal.
Heart health and brain size
When the scores were matched to brain measurements, they found a relationship. Individuals with higher heart health scores at the start of the study had a higher-than-average brain volume as a percentage of their total head size in middle age. Similarly, brain size was larger for people who had higher averages in their initial and final scores.
Every point increase in the Life's Simple 7 score equated to "1 year of aging in the amount of brain shrinkage that occurred."
"These findings are exciting because these are all changes that anyone can make at a young age to help themselves live a long and healthy life. This may mean that heart health may have an impact on brain function in early life, but more study needs to be done to confirm this theory."
Michael Bancks, Ph.D.
The results are intriguing, but, as Dr. Bancks points out, there will need to be more study. The findings are limited because the brain scans were only done at one point in time. Having said that, they do line up well with other studies in a similar vein.
From these findings alone, we cannot know whether heart health directly affects brain size, or if brain size in youth negatively influences behaviors that impact heart health. More research is sure to follow.