Exaggerated blood pressure reaction to mental stress predicts cardiovascular risk

May 16 2005

When mental stress sparks a significant rise in blood pressure, it may be a sign of other existing cardiovascular risk factors, researchers reported today at the American Society of Hypertension’s Twentieth Annual Scientific Meeting.

"What we have observed is that blood pressure rises during times of mental stress but varies in level from patient to patient," said Dr. Roberto A. Ingaramo, from CEHTA Cardiovascular in Trelew, Argentina. "This disparity in blood pressure response suggests that other risk factors associated with cardiovascular disease may play a role."

"As physicians, we are concerned about both the mental and physical well-beings of our patients," said Dr. Ingaramo. "It is important to know how seriously we should interpret significant changes in blood pressure as a response to mental stress, and for this reason we decided to investigate this association."

The study looked at whether an exaggerated blood pressure response to mental stress was related more closely to cardiovascular risk and evidence of target organ damage than a normal, less significant, blood pressure response. Sixty-seven patients went through a 24-hour ambulatory blood pressure monitoring period and overnight fasting, followed by a computerized version of the Stroop word conflict stress test and a 15-minute mental arithmetic test. During this time period, blood pressure was

measured every 5 minutes. Those who experienced an 25 mm Hg or greater increase in systolic blood pressure, a 15 mm Hg or greater increase in diastolic blood pressure, or a mean blood pressure increase of 20 percent or greater with respect to baseline values were considered exaggerated responders.

"If a patient experiences more than 20 percent increase in blood pressure due to mental stress, there is an abnormal activation of the sympathetic nervous system, that could be damaging, for the patient’s blood vessels and vital organs," said Dr. Ingaramo.

The results showed that 35 patients, 29 of whom had existing hypertension, exhibited an exaggerated blood pressure response to the mental stress test. When comparing these patients to the 32 patients exhibiting a normal blood pressure response, the researchers observed a greater prevalence of hypertension (83 percent versus 59 percent, p=0.031) and greater average serum creatinine levels (92.17 +/-17.5 versus 81.75 +/- 15.2, p=0.016). However, between all patients there were no differences in traditional markers of target organ damage such as left ventricular mass index, carodita intima-media thickness, or renal resistive index.

"Our results show that the exaggerated response is associated with hypertension and elevated plasmatic creatinine levels, which is a measurement of kidney function," said Dr. Ingaramo. "While the results show a promising look into the association between mental change and physical function, larger studies will be needed to validate these findings and determine how they can be applied in clinical practice."