Thirty-Minute Office Blood Pressure Monitoring in Primary Care

Automated office blood pressure monitoring during 30 minutes (OBP30) may reduce overtreatment of patients with white-coat hypertension in primary health care. OBP30 results approximate those of ambulatory blood pressure monitoring, but OBP30 is much more convenient. In this study, we compared OBP30 with routine office blood pressure (OBP) readings for different indications in primary care and evaluated how OBP30 influenced the medication prescribing of family physicians.

All consecutive patients who underwent OBP30 for medical reasons over a 6-month period in a single primary health care center in the Netherlands were enrolled. We compared patients' OBP30 results with their last preceding routine OBP reading, and we asked their physicians why they ordered OBP30, how they treated their patients, and how they would have treated their patients without it.

We enrolled 201 patients (mean age 68.6 years, 56.7% women). The mean systolic OBP30 was 22.8 mm Hg lower than the mean systolic OBP (95% CI, 19.8-26.1 mm Hg). The mean diastolic OBP30 was 11.6 mm Hg lower than the mean diastolic OBP (95% CI, 10.2-13.1 mm Hg). Considerable differences between OBP and OBP30 existed in patients with and without suspected white-coat hypertension, and differences were larger in individuals aged 70 years or older. Based on OBP alone, physicians said they would have started or intensified medication therapy in 79.1% of the studied cases (95% CI, 73.6%-84.6%). In fact, with the results of OBP30 available, physicians started or intensified medication therapy in 24.9% of cases (95% CI, 18.9%-30.9%).

OBP30 yields considerably lower blood pressure readings than OBP in all studied patient groups. OBP30 is a promising technique to reduce overtreatment of white-coat hypertension in primary health care.