Pseudohypertension in the elderly.

Pseudohypertension is a condition in which indirect blood pressure measured by the cuff method overestimates the true intra-arterial blood pressure. Despite the clinical importance of pseudohypertension, reports regarding its prevalence are scarce. We compared direct measurements of brachial arterial blood pressure with those measured indirectly by the cuff method in 59 healthy volunteers aged greater than 65 years, with or without hypertension, in order to investigate the prevalence of pseudohypertension in the elderly. The average systolic blood pressure of 161.5 mmHg obtained by the indirect method was significantly lower than the 169.2 mmHg obtained by the direct method was not significantly different from the 76.9 mmHg obtained by the direct method. Only one volunteer was observed in whom the indirect cuff method overestimated the diastolic blood pressure by greater than 10 mmHg, which was defined as pseudohypertension. Thus, the prevalence of pseudohypertension was only 1.7%. The difference in systolic blood pressure between the two methods was 8.7 mmHg in Osler-positive cases and was not significantly different from the 6.9 mmHg observed in Osler-negative cases. Pulse wave velocity was significantly correlated with the systolic blood pressure (y = 11.4x + 66.1, r = 0.65, P less than 0.05). No correlation was observed between the pulse wave velocity and direct/indirect pressure differences for either systolic or diastolic measurements. These results show that the prevalence of pseudohypertension is very low in a non-selected elderly population and that Osler's maneuver was not related to the pressure difference between the direct and indirect methods.