“The assumption by many in medicine has been that brain damage manifests over years of evident blood pressure (BP) elevation in older people,” says H. Lina Schaare, PhD-candidate. “But asymptomatic brain changes, which can be seen on MRI, precede pathologic conditions by many years.” For a study published in Neurology, Schaare and colleagues sought to test whether elevated BP relates to gray matter volume (GMV) differences in young adults without hypertension, Schaare and colleagues assessed brain MRI data on healthy participants aged 19 to 40 years.

The researchers conducted statistical mapping to detect subtle differences in gray matter volumes among young adults how had undergone seated BP measurements and T1-weighted structural head MRI scans. BP was categorized according to the 2013 European guidelines for the management of arterial hypertension, and analyses were performed with BP as a continuous variable.

Overall, the study showed that BP above 120/80 mm Hg was linked to reduced GMV in areas including the frontal and parietal lobes, as well as the hippocampus, amygdala and thalamus, among other regions.

“BP of 120/80 mm Hg or greater was associated with lower GMV in regions that have previously been related to gray matter decline in older individuals with manifest hypertension,” explains Schaare. She adds that BP-associated gray matter alterations emerged continuously across the range of BP and earlier in adulthood than previously assumed, suggesting that treating hypertension or maintaining lower BP in early adulthood might be essential for preventing the pathophysiologic cascade of asymptomatic cerebrovascular disease to symptomatic end-organ damage, such as stroke or dementia.

“Our research provides new insights about the relationship between BP levels and the brain,” Schaare says, “emphasizing the importance of BP variations in so-called ‘normal’ ranges for young adults’ brain integrity.”

References

Association of peripheral blood pressure with gray matter volume in 19- to 40-year-old adults
http://n.neurology.org/content/early/2019/01/23/WNL.0000000000006947