Columbia University Medical Center

Innovators: Ian Kronish, Center for Behavioral Cardiovascular Health

Does Your Patient Really Have Hypertension?
Tap Into Our New Ambulatory Blood Pressure Program

Most clinicians know that a blood pressure reading obtained from a patient while in the doctor’s office doesn’t necessarily reflect whether or not that person actually has hypertension. There is the familiar phenomenon of “white coat” hypertension, in which a patient’s nervousness about being in the medical setting causes blood pressure to spike when it’s usually within a normal range.

Ian Kronish

Ian Kronish, MD, MPH, ColumbiaDoctors

“Approximately one in five patients with elevated blood pressure during hypertension screening in the clinic have white coat hypertension and do not need to take medication,” said Ian Kronish, MD, MPH, assistant professor of medicine. He is also a researcher in Columbia’s Center for Behavioral Cardiovascular Health, an interdisciplinary team of scientists that studies how and why behaviors, psychological factors, and societal forces influence hypertension and cardiovascular disease.

Less well-known is the opposite phenomenon: “masked hypertension,” in which blood pressure appears normal during a physician’s visit, but jumps into the hypertensive range at other times during the day or night. “Masked hypertension is particularly common in African-Americans, approaching 30 percent to 50 percent in some studies,” Dr. Kronish noted. “Masked hypertension can also be the first clue that a patient has obstructive sleep apnea.”

The center’s founder, the late Thomas G. Pickering, MD, MPhil, was an early proponent of ambulatory monitoring, who notably coined the terms “white coat hypertension and “masked hypertension.”

For 20 years, Columbia’s program researched hypertension, and patients could receive ambulatory monitoring as part of that research. “We thought it was a shame that this service wasn’t available to all patients,” Kronish said. He added that “what pushed us over the edge was a groundbreaking guideline from the US Preventive Services Task Force,” which concluded that ambulatory blood pressure monitoring should be the reference standard for confirming office-based diagnosis for most patients.

The report states that “although the criteria for establishing hypertension varied across studies, there was significant discordance between the office diagnosis of hypertension and 12- and 24-hour average blood pressures using ABPM, with significantly fewer patients requiring treatment based on ABPM. Elevated ambulatory systolic blood pressure was consistently and significantly associated with increased risk of fatal and nonfatal stroke and cardiovascular events, independent of office blood pressure.”

With funding from the Agency for Healthcare Research and Quality (AHRQ) and Kronish as the principal investigator, the center was charged with finding a way to “get doctors to follow diagnostic guidelines.” As a result, the ActiveBP program was born.

The center’s new Active BP ambulatory blood pressure monitoring program is designed to identify a patient’s true blood pressure range over time, rather than at a single time point in the physician’s office. Patients are given an ambulatory blood pressure monitor (ABPM) which attaches to a belt worn around the body. Every 30 minutes for a 24-hour period–including while the patient sleeps–the cuff takes a blood pressure reading, providing a comprehensive report on the patient’s blood pressure while doing normal daily activities.

The device can be placed by trained coordinators at the center, and can be returned either in person or by mail. After the 24-hour period, when the device is returned, specialists will analyze the readings and provide the patient and their physician with an interpretation of the results. Patients receive a comprehensive report of their results, like this sample patient reportThe patient’s primary care provider or cardiologist receives a report, like this sample, and can provide additional feedback to the patient.

Most ABPM assessments are reimbursable by third-party payers. For more information, contact the center at 212-342-1273 or email activebp@cumc.columbia.edu.