Young adults who react to psychological stress with spikes in blood pressure are at increased risk to develop hypertension by middle age, according to an article in the June 22nd rapid access issue of Circulation.

“In general, the individuals who had larger blood pressure responses to stress, had a greater risk for developing high blood pressure,” said Karen A. Matthews, PhD, lead author. “This risk was independent of other known risk factors such as race, gender, education, age, and body-mass index.”

The current findings are based on data collected in the American CARDIA study, which is an ongoing prospective study tracking the natural history of cardiovascular disease. From 1985 to 1986, the study enrolled 5,115 men and women ages 18 to 30 years. Patients were reexamined at 2-, 5-, 7-, 10-, and 15-year intervals.

At the 2-year examination, 4,202 participants completed stress testing. These participants had normal blood pressure at this examination, with a systolic pressure of less than 140 mmHg and diastolic pressure of less than 90 mmHg. Participants were considered to have hypertension if their pressure was 140/90 mmHg or higher at a follow-up visit or if they were taking antihypertensive medications.

Participants took three different stress tests and researchers measured the change in their blood pressure. In the cold pressor test, participants plunged a hand in ice cold water and kept it submerged for 45 seconds. Another test, star tracing, required participants to trace a star with a stylus through a mirror image of the star. Last, participants played a video game, but Matthews noted that since the tests were done in the late 1980s, video games were more novel than now.

“In general, participants who had the greatest blood pressure increases during all three tasks had the highest risk for later high blood pressure,” said co-author Mary A. Whooley, MD.

In addition, the greater the blood pressure changes in all three tasks, the earlier the onset of hypertension, Whooley said. “Take, for instance, two women similar with characteristics such as age, education, and body mass index. One of the women is in the top quarter of change in blood pressure due to stress while the other is in the lowest quarter. The woman who was very reactive was also among those who developed hypertension the soonest.”

Each unit increase in blood pressure change was associated with a 9 to 12 percent decrease in time to systolic hypertension and a 12 percent to 18 percent decrease in time to diastolic hypertension.

The study didn’t assess ways to reduce blood pressure spikes caused by stress, but Matthews said that one plausible?although unproven?way to reduce the stress risk is by exercise: “People who are active and physically fit may have smaller stress responses or their blood pressure may return to normal more quickly.”

After 13 years of follow-up, 353 participants developed hypertension.

“This study confirms previous work demonstrating an association between blood pressure response to various stressors and the future development of hypertension,” said American Heart Association spokesperson Daniel W. Jones, MD. “It is still unclear whether exposure to stress is a part of the cause of hypertension in some people or whether these tests measuring response to stress are simply good markers for the future development of hypertension. Further research in this area is needed to understand the role of stress in the development of hypertension and possible management tools for reducing that risk.”