Correlation Between Objective Automatic and Auscultatory Mercury Manometer Blood Pressure Measurements

Abstract

The automatic blood pressure (BP) measurement device (A) developed for the World Health Organization (WHO) Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study was compared in Spain with the standard auscultatory-mercury manometer (M) in 440 randomly selected subjects, 50–54 years old (50% men and 50% women). BPs were recorded simultaneously in the same arm. Systolic BP (SBP), analyzed in 1,440 readings, was 127.5 ± 18.9 mm Hg by A system and 127.6 ± 18.6 mm Hg by M system (NS). Diastolic BP (DBP) was 71.3 ± 11.7 mm Hg by A and 79.3 ± 11 mm Hg by M (p < 0.001). We confirmed good correlations in SBP and DBP measured by both methods (r = 0.95 and r = 0.88, respectively; both p < 0.001). Nearly complete consistency was noted between SBP readings by both methods but not between DBP readings; the readings by M were significantly higher than those by A. Since A's consistency with SBP and DBP readings obtained by the intra-arterial method (the most commonly used method) previously had been proven to be satisfactory, DBP obtained by clinical practice is possibly overestimated in adults.