Nav: Home

Clinic readings may underestimate blood pressure during daily activities

December 05, 2016

DALLAS, Dec. 5, 2016 -- Around the clock monitoring during daily activity revealed masked, or undetected, high blood pressure among otherwise healthy adults who had normal readings in the clinic, according to new research in the American Heart Association's journal Circulation.

The reverse of "white coat hypertension" (higher blood pressure readings at the doctor's office than outside the clinic setting), "masked hypertension" is normal blood pressure in the doctor's office but high readings outside of the office.

Masked hypertension is easy to miss, and can occur during the day or night. Masked hypertension is uncovered with 24-hour ambulatory, or around the clock, monitoring. Patients go about their daily activities while wearing a blood pressure cuff on their arm, attached to a small, portable device. Compared to clinic blood pressure, ambulatory blood pressure is recognized as a better predictor of future cardiovascular disease.

The common belief was that ambulatory blood pressure is usually lower than clinic blood pressure, in part because of the so-called "white-coat effect" caused by increased anxiety from clinic testing.

In this study, researchers compared clinic blood pressure measurements to ambulatory blood pressure monitoring in 888 healthy, middle-aged participants enrolled in the Masked Hypertension Study at Stony Brook University and Columbia University in New York between 2005 and 2012.

They found:
  • 15.7 percent of participants with normal clinic blood pressure had masked hypertension based on ambulatory monitoring, regardless of sex, race, or ethnicity.

  • Younger, normal-weight participants were more likely than older, overweight participants to have ambulatory blood pressure readings higher than their clinic readings.

"These findings debunk the widely held belief that ambulatory blood pressure is usually lower than clinic blood pressure," Joseph E. Schwartz, Ph.D., study lead author and professor of psychiatry and sociology, at Stony Brook University, in Stony Brook, New York. "It is important for healthcare 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. Our study's results may not apply to those who have previously been diagnosed as having hypertension or are already being treated for hypertension."

Study participants had three blood-pressure readings taken during each of three clinic visits and completed one 24-hour ambulatory blood pressure recording (with readings taken approximately every 30 minutes). At the time of the study, all participants were employed and were not taking medication to lower blood pressure. More than half of participants were female, and their average age was 45. Most participants were white, 7 percent were African American, and 12 percent were Hispanic.

All participants were employed which excluded retired, older people who are more likely than younger adults to have high blood pressure. Researchers said their research needs to be confirmed in further studies with more diverse populations.

There are a substantial number of otherwise healthy individuals who have masked hypertension and should have their blood pressure monitored regularly; it is critical that future research determine if these individuals would benefit from treatment, researchers said.
-end-
Co-authors are Mathew M. Burg, Ph.D.; Daichi Shimbo, M.D.; Joan E. Broderick, Ph.D.; Arthur A. Stone, Ph.D.; Joji Ishikawa, M.D.; Richard Sloan, Ph.D.; Tyla Yurgel, M.A.; Steve Grossman, M.S.; and Thomas G. Pickering, M.D. (posthumously). Author disclosures are on the manuscript.

The National Heart, Lung, and Blood Institute and the National Center for Advancing Translational Sciences (formerly the National Center for Research Resources) supported the study.

Additional Resources:

Blood pressure images are located in the right column of this release link http://newsroom.heart.org/news/clinic-readings-may-underestimate-blood-pressure-during-daily-activities?preview=0ed69b5876a4e412b937771f1ace56ee

Around-the-clock monitoring may unmask hypertension in African-Americans
Follow AHA/ASA news on Twitter @HeartNews.
For updates and new science from the Circulation journal follow @CircAHA.

Statements and conclusions of study authors published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association's policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at http://www.heart.org/corporatefunding.

American Heart Association

Related Hypertension Articles:

Overactive enzyme causes hereditary hypertension
After more than 40 years, several teams at the MDC and ECRC have now made a breakthrough discovery with the help of two animal models: they have proven that an altered gene encoding the enzyme PDE3A causes an inherited form of high blood pressure.
Diagnosing hypertension in children
Study results call into question the utility of testing blood pressure load--the proportion of elevated blood pressure readings detected over 24 hours--for diagnosing hypertension in children.
When the best treatment for hypertension is to wait
A new study concluded that a physician's decision not to intensify hypertension treatment is often a contextually appropriate choice.
Treatment of hypertension induced albuminuria
Patients with albuminuria will usually need more than one drug to achieve blood pressure control, particularly if the aim is also to reduce albuminuria.
Diagnosing and treating resistant hypertension
Resistant blood pressure affects 12 percent to 15 percent of people currently being treated for high blood pressure.
Dementia can be caused by hypertension
A new study in Cardiovascular Research indicates that patients with high blood pressure are at a higher risk of developing dementia.
Hormone imbalance causes treatment-resistant hypertension
British researchers have discovered a hormone imbalance that explains why it is very difficult to control blood pressure in around 10 per cent of hypertension patients.
Breastfeeding reduces hypertension risk
A study published in the American Journal of Hypertension indicates that women who breastfeed more children, and for longer periods of time, are less likely to suffer from hypertension after they reach menopause.
Lung cancer triggers pulmonary hypertension
Nearly half of all advanced-stage lung cancer patients develop arterial pulmonary hypertension.
Targeting mitochondria in pulmonary hypertension
Investigators at the University of Alberta and the Imperial College of Medicine have shown that the generic drug, Dichloroacetate (DCA), can decrease the blood pressure in the lungs of pulmonary arterial hypertension patients and improve their ability to walk, without significant side effects at the doses tested.
More Hypertension News and Hypertension Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Warped Reality
False information on the internet makes it harder and harder to know what's true, and the consequences have been devastating. This hour, TED speakers explore ideas around technology and deception. Guests include law professor Danielle Citron, journalist Andrew Marantz, and computer scientist Joy Buolamwini.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.