Blood pressure estimation and beliefs among normotensives and hypertensives.

Although health professionals believe that blood pressure (BP) is asymptomatic, most diagnosed hypertensives are confident that they experience specific symptoms and emotions that help them detect their BP levels. Several months after screening interviews that elicited subjects' BP beliefs, 14 medicated hypertensives, 15 nonmedicated mild hypertensives (diastolic BP greater than or equal to 90 mm Hg), 39 normotensives, and 13 hypotensives (systolic BP less than or equal to 100 mm Hg) participated in a 1- to 2-hr laboratory experiment that assessed each subject's symptoms, moods, and estimates of systolic BP (SBP) relative to actual SBP levels. Several self-reports and autonomic measures were collected 45 times during and after each of 22 tasks. Subjects never received SBP feedback during the experiment. Within-subject correlations indicated that all subject groups could estimate SBP at levels greater than chance (mean estimated SBP-actual SBP correlation = .25). Further, 68% of the subjects evidenced at least one significant symptom-SBP correlation. Although medicated hypertensives believed they could estimate their BP more accurately than other groups by using their symptoms and emotions, they were actually no more accurate than the other groups. They also evidenced far fewer empirically derived symptom-SBP and emotion-SBP correlations than any other group. Overall, BP beliefs were largely inaccurate. If these erroneous beliefs can be eliminated, subjects may be able to estimate BP fluctuations more accurately.