To find the answer, the researchers monitored the blood flow through each participant's veins in different scenarios that might constrict the veins, such as having one foot immersed in cold water, or while squeezing a handgrip. They also administered a nitroglycerin pill under the tongue of each participant to relax the veins. In each case, they found that the tests had no effect on the response of the veins in either age group.
"Thus, we think that the stiffening of our veins as we age is probably due to structural changes, such as a thickening of the vein walls," Farquhar said. "Hardening of the arteries is a good analogy for what is happening in our veins as we grow older."
So can we do anything to keep our veins limber as time marches on?
"While there have been no longitudinal studies of this yet, it's possible that regular exercise training may blunt age-related increases in vein stiffness," Farquhar notes.
In the second phase of the UD study, now under way, the research team wants to find out if the veins of people with high pressure are stiffer than the veins of people with normal blood pressure. Two doctoral students, Erin Delaney and Megan Wenner, are assisting with this portion of the research, which will examine both young and older adults with high blood pressure.
While high blood pressure is all too common among older adults, Farquhar said it can be harder to find young adults who already have the disease. However, several individuals already have been identified for the study, and the team hopes to have data to report in the next six months.
This research is both literally and figuratively "close to the heart
Source:University of Delaware