Uncertainty about what the patients blood pressure was one of the largest factors. Providers variably repeated the blood pressure check once the patient was in the exam room, and not surprisingly were much less likely to change treatment if the new reading was lower than 140/90 mm Hg. Only 13 percent of such patients had a treatment change, compared with 61 percent of those with a high second reading, or who didnt get one.
Providers clearly trust their own reading more than they do the reading taken at the clinic intake point, suggests Hofer. But there is no evidence that supports that approach. In fact, the literature suggests that provider measurements are less reliable and subject to large biases relative to independent measures by nurses using electronic blood pressure cuffs.
Additionally providers responded to their patients own report about what kind of readings he or she was getting using a home blood pressure monitor. Only 18 percent of patients who told their providers their home measurements had been below 140/90 mm Hg received a treatment change, compared with 52 percent who said their pressures at home had been high, or who didnt report at-home monitoring.
While at-home monitoring can be important, Kerr says, the fact of the matter is that there is no standard for how often to monitor and how to record home pressure readings over time. Further, patients might preferentially report only the normal blood pressures and ignore the out-of-range values.
Patients should talk to their doctors about how often to monitor and record their blood pressure and look at averages over time, she says. If their average is above the target, it might be time to change treatment.
|Contact: Kara Gavin|
University of Michigan Health System