HealthDay News — Ambulatory blood pressure may be a better indicator of health risks than clinic blood pressure, according to a new report published online December 6 in Circulation.
Researchers took three blood pressure readings during each of three clinic visits, for a total of nine. The study participants also had their ambulatory blood pressure monitored once for 24 hours, with readings taken about every half-hour. During monitoring, patients wore a cuff on their arm attached to a small device that recorded their blood pressure. All participants were employed and not taking blood pressure medication. Their average age was 45, and about 80% were white.
The researchers found that, overall, 15.7% of participants with normal clinic readings met the criterion for having hypertension based on their average awake ambulatory blood pressure. On average, ambulatory systolic pressure was about 7 mmHg higher than systolic blood pressure measured in the clinic. Diastolic pressure was about 2 mmHg higher during 24-hour monitoring than in the clinic. For more than one-third of participants, systolic pressure was 10 mmHg higher during all-day monitoring than at the clinic. A similar jump was noted in diastolic blood pressure for nearly one in 10 participants. Difference in readings was most common for young, lean patients versus older or overweight individuals.
“In working individuals who are not being treated for hypertension, our data show that ambulatory blood pressure is usually higher than clinic blood pressure,” lead researcher Joseph Schwartz, PhD, a professor of psychiatry and sociology at Stony Brook University in New York, told HealthDay. “It is critical that we learn what, if anything, should be done to lower their ambulatory blood pressures.”