Poorer cardiovascular fitness and elevated heart rate and blood pressure during exercise at middle-age have been linked to lower brain volume later in life. The findings were published in Neurology.
Exercise is known to be associated with neuroplasticity, increased cerebral blood flow, and prevention of age-related atrophy.
“Brain volume is one marker of brain aging. Our brains shrink as we age, and this atrophy is related to cognitive decline and increased risk for dementia. So it is important to determine the factors (especially modifiable factors, such as fitness) that contribute to brain aging,” Nicole Spartano, PhD, study author and postdoctoral fellow at Whitaker Cardiovascular Institute at Boston University School of Medicine, told Neurology Advisor.
Dr Spartano and colleagues used data from the Framingham Offspring study to assess the relationship between cardiovascular fitness, exaggerated heart rate, and blood pressure with brain morphology. The cohort consisted of 1094 participants (53.9% female) without dementia or cardiovascular disease. At midlife (mean age 40 years), the participants underwent an exercise stress test; 2 decades later, an MRI and repeat stress test were performed (mean age 58 years).
During the 19-year follow-up, hypertension prevalence increased from 9% to 28% along with resting and exercise systolic blood pressure. At baseline, 89% of participants achieved target heart rate. Aa lower estimated exercise capacity at baseline was associated with lower total cerebral brain volume at follow-up, with 1 SD lower exercise capacity equivalent to more than 1 year of accelerated brain aging.
Greater exercise diastolic blood pressure and heart rate response at baseline was also associated with lower total cerebral brain volume in the fully adjusted models. Exercise systolic blood pressure was associated with lower total cerebral brain volume after adjustment in participants with a history of hypertension or prehypertension at baseline. Likewise, higher exercise heart rate at baseline was associated with lower volume in the frontal lobe at follow-up, and higher exercise heart rate later in life was associated with both lower frontal lobe and total cerebral brain volume.
“Health and lifestyle choices that you make throughout your life may have consequences many years later,” Dr Spartano said. “This message may be especially important for people with heart disease or at risk for heart disease, in which we found an even stronger relationship between fitness and brain aging.”
“These findings should not be interpreted to suggest that exercise is harmful,” the authors wrote.” “Rather, exercise is the stress that uncovers the vascular dysfunction likely resulting in smaller brain volumes.”