Abstract 167: Age and Gender Differences in Pulse Pressure Response to Repeat Blood Pressure Measurement After Brief Patient Rest Period

Abstract

BACKGROUND: Increased pulse pressure (PP) is an independent determinant of cardiac disease. The effect of rest period on office-based systolic blood pressure has been previously reported, but not on PP in particular. OBJECTIVE: To assess the effect of age and gender on repeat PP measurement after a brief rest period in an outpatient cardiology clinic. METHODS: Patient charts reviewed in University-based cardiology clinic identified 170 encounters which contained BP re-measurement data due to elevated initial BP of > 130/80 mmHg. BP was measured initially by a nurse, with the patient in a sitting position and the arm resting at the level of the heart. If BP was > 130/80 mmHg, it was repeated by physician after resting the patient for 15 minutes. There were 112 (66%) elderly patients ≥ 60 years of age and 58 (34%) younger patients < 60 years of age. Among the elderly patients, there were 51 males (46%) and 61 females (54%). RESULTS: Among all encounters, after a brief rest period, initial PP of 67 ± 2 mmHg decreased to 62 ± 1 mmHg (5 mmHg; P < 0.01). PP decreased by 8 mmHg in the elderly (72 ± 2 to 64 ± 2 mmHg; P < 0.01) but did not significantly change in the young (56 ± 3 to 58 ± 3 mmHg; P = 0.3). PP decrease among the elderly was more pronounced in females (11 mmHg; 76 ± 4 to 65 ± 2 mmHg; P < 0.01) compared with males (4 mmHg; 68 ± 3 to 64 ± 2 mmHg; P = 0.03).DISCUSSION: Hypertension is a challenging public health problem. JNC 7 guidelines recommend that prior to BP measurement, persons should be seated quietly for at least 5 minutes in a chair, with feet on the floor, and arm supported at heart level; which resulted in significant decrease in pulse pressure in our patients. We show that while a decrease in pulse pressure was confined to the elderly, elderly females had a more pronounced PP decrease compared to males; both, however, fell to the same level. White coat hypertension may explain this observation, since it is more frequent in elderly females. The implication of this observation is that physicians should take extra care in remeasuring the blood pressure and pulse pressure, especially in elderly females, in whom a more pronounced drop in pressure may be observed after a brief rest period, and thereby, result in reclassifying their risk and need for treatment.