A new study published in the American Heart Association’s journal Circulation found alarming rates of masked, or undetected, high blood pressure in healthy adults who had normal readings in the clinic. The researchers, out of Stony Brook University and Columbia University, monitored the blood pressure of 888 participants around the clock during daily activity. (Don’t miss the 31 things you can do right now to lower your blood pressure.)
When monitored, patients wore a cuff on their arm attached to a small device that recorded their blood pressure. Participants had three blood pressure readings taken during all three clinic visits, and finished one 24-hour ambulatory blood pressure recording, with readings administered every 30 minutes. None of the participants—more than half of them women, age 45 on average, were taking blood pressure medication to lower their numbers. (These are the 9 surprising factors that could affect your blood pressure reading.)
The results of the study, led by Joseph E. Schwartz, PhD, of Stony Brook University, revealed that 15.7 percent of participants with normal clinic blood pressure had masked hypertension, and younger, normal weight participants had higher ambulatory blood pressure readings than older, overweight participants.
“These findings debunk the widely held belief that ambulatory blood pressure is usually lower than clinic blood pressure,” said Dr. Schwartz, Professor of Psychiatry and Sociology at Stony Brook and Lecturer at Columbia University. “It is important for health-care providers to know that there is a systematic tendency for ambulatory blood pressure to exceed clinic blood pressure in healthy, untreated individuals evaluated for hypertension during well-patient visits.”
Masked hypertension is the opposite of white coat hypertension, in which the stress of the medical setting provokes wrongly detected high blood pressures.
The masked version can be difficult to catch, and it’s not completely clear what causes the condition, but it is known to be more common in men, tobacco users, those who drink alcohol excessively, and people with diabetes. It may also be stress-induced, and because people have so much stress at work, or even at home, they find a bit of solace in their doctor’s office, causing them to chill out and provide false blood pressure results.
High blood pressure can contribute to stroke, heart failure, vision loss, and kidney failure, heightening concerns over the condition.
Dr. Gerald Fletcher, a spokesman for the American Heart Association, isn’t surprised by the findings. “It’s a major problem in our population,” he told Reader’s Digest. “People aren’t doing enough to keep their numbers low.” And though likely beneficial given the statistics of high blood pressure in the U.S., it’s simply not possible to monitor everyone around the clock. Fletcher suggested starting with preventative measures.
“People put salt on their food before even tasting it. Sodium is a major contributor to high blood pressure and needs to be restricted.” He also urged people to get more active. “Exercise is wonderful for blood pressure,” he said. “And the opportunities are always there.” Traveling? Go to your hotel gym. Don’t like venturing far from your house? Purchase exercise equipment for your home. “Even just going for a walk is great,” he said.
“Monitoring blood pressure is as easy as measuring your waist,” Fletcher said, advising that people need to be more diligent about having their blood pressure recorded to save lives, especially considering those with elevated blood pressure often don’t know they have it because they feel fine.