Multiple clinic and home blood pressure measurements versus ambulatory blood pressure monitoring

Abstract

To compare multiple clinic and home blood pressure (BP) measurements and ambulatory BP monitoring in the clinical evaluation of hypertension, we studied 239 middle-aged pharmacologically untreated hypertensive men and women who were referred to the study from the primary healthcare provider. Ambulatory BP monitoring was successfully completed for 233 patients. Clinic BP was measured by a trained nurse with a mercury sphygmomanometer and averaged over 4 duplicate measures. Self-recorded home BP was measured with a semiautomatic oscillometric device twice every morning and twice every evening on 7 consecutive days. Ambulatory BP was recorded with an auscultatory device. Two-dimensionally controlled M-mode echocardiography was successfully performed on 232 patients. Twenty-four-hour urinary albumin was determined by nephelometry. Clinic BP was 144.5+/-12.6/94.5+/-7.4 mm Hg, home BP (the mean of 14 self-recorded measures) was 138.9+/-13.1/92.9+/-8.6 mm Hg, home morning BP (the mean of the first 4 duplicate morning measures) was 137.1+/-13.7/92.4+/-9.2 mm Hg, daytime ambulatory BP was 148.3+/-13. 9/91.9+/-7.8 mm Hg, nighttime ambulatory BP was 125.5+/-16.4/75. 6+/-8.9 mm Hg, and 24-hour ambulatory BP was 141.7+/-14.0/87.2+/-7.6 mm Hg. Pearson correlation coefficients of clinic, home, home morning, and daytime ambulatory BPs to albuminuria and to the characteristics of the left ventricle were nearly equal. In multivariate regression analyses, 36% (P<0.0001) of the cross-sectional variation in left ventricular mass index was attributed to gender and home morning systolic BP in models that originally included age, gender, and clinic, self-measured home morning, and ambulatory daytime, nighttime, and 24-hour systolic and diastolic BPs. We concluded that carefully controlled nonphysician-measured clinic and self-measured home BPs, when averaged over 4 duplicate measurements, are as reliable as ambulatory BP monitoring in the clinical evaluation of untreated hypertension.