If you're worried about hypertension, new research suggests that you're better off texting than talking on your mobile phone—taking a cell phone call can cause immediate spikes in blood pressure.

The claim comes from preliminary research presented this week at the 28th Annual Scientific Meeting of the American Society of Hypertension (ASH) in San Francisco, conducted by researchers from Guglielmo da Saliceto Hospital in Italy.

Do Cell Phone Calls Affect Hypertension?

The study, conducted on 94 middle-aged participants who were taking medication for mild to moderate hypertension, was meant to find out whether taking cellular phone calls during blood pressure monitoring affected the measurements.

Before the test, researchers asked patients how often they spoke on cell phones, and then took down their phone numbers.

The patients then underwent two series of six blood pressure measurements as they sat alone in an armchair, with a monitor that took readings at automatic one-minute intervals. At each interval, the device measured systolic and diastolic blood pressure and heart rate.

During either the first or second of the two series, an investigator called the patient's cell phone three times with an unknown calling number, until the patient picked up the phone and spoke.

The investigators then compared the average blood pressure and heart rate measures with and without phone calls.

Phone Call Interruptions Can Raise Blood Pressure

The results showed that when patients answered the cell phone calls, their average blood pressure rose from 121/77 to 129/82. Heart rate did not change significantly.

The rise in systolic blood pressure (the top number in a blood pressure reading) was less apparent in patients who used their cell phones more than 30 times a day, as well as those who were taking beta-adrenergic blockers to lower their blood pressure.

Dr. Giuseppe Crippa said in a news release that he is unsure why using cell phones more often might reduce the blood pressure spike.

One explanation, he suggested, is that the patients who habitually made mobile phone calls were younger, "which could show that younger people are less prone to be disturbed by telephone intrusions."

Another reason could be that frequent cell phone users are actually calmed by the constant presence of their mobile device, which wards of the anxiety of missing out on the latest information.

Implications for Cell Phone Users

Since the study participants received their phone calls in a very specific condition—a medical visit—and from an unknown number, it's unclear how generalizable the findings are for other cell phone users in everyday life.

The results should be viewed as preliminary until they are peer-reviewed in an academic journal.

Previous research suggests that the mere act of talking during blood pressure monitoring can skew measurements, so the effect may not be specific to cell phone use.

Even if these findings can be replicated in other studies, it's possible that receiving a cell phone call from a friend or loved one might have no effect on a person's blood pressure, or might even improve it. Previous studies suggest that strong social connections are linked to healthier blood pressure.

The most specific conclusion one can draw from the results is that people should turn off their cell phones while monitoring their blood pressure.

Hypertension affects about one billion people around the world, and the World Health Organization (WHO) estimates that 13 percent of all deaths are a result of high blood pressure.

A third of American adults have high blood pressure, according to estimates from the Centers for Disease Control and Prevention (CDC).

With a figure that high, it's difficult to pinpoint just one cause of hypertension. While 87 percent of American adults used a mobile phone as of December 2012, more salient causes of high blood pressure may include salty diets, emotional stress, and poor posture.


G Crippa, D Zabzuni, A Cassi, E Bravi. Mobile Phone Calls Acutely Increase Blood Pressure Levels in Hypertensive Subjects [abstract]. Journal of Clinical Hypertension. May 2013.