Is blood pressure measurement with a standard cuff reliable?
This study compares blood pressures measured with a standard cuff (rubber bag 12 x 35 cm) with concomitantly measured intra-arterial pressures in 48 subjects. With the standard cuff, and using a diagnostic cut-off limit for diastolic hypertension of 90 mmHg, 15/48 patients were found to be hypertensive, whereas only 4/48 had intraarterial pressure above 90 mmHg. Thus, the specificity of the non-invasive method was only 75%. If higher diagnostic cut-off limits were used, e.g. 95 mmHg, specificity increased to 84%, and with lower cut-offs specificity was 63% for 85 mmHg and 52% for 80 mmHg. A specificity of only 75% is very poor for a method commonly used in screening examinations and may lead to considerable over-diagnosis of mild hypertension.
Stolt
M
M
Department of Development of Primary Health Care, County Council West, Stockholm, Sweden.
Sjönell
G
G
Aström
H
H
Hansson
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D001795:Blood Pressure Determination / Q000295:instrumentation* / Q000592:standards*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity