Orthostatic Blood Pressure, Cardiovascular Disease, and Hypotensive Events.

backgroundOrthostatic hypotension is thought to be associated with coronary heart disease, falls, and syncope due to low blood pressure (BP) upon standing.

methodsThe ARIC (Atherosclerosis Risk in Communities) study measured supine and standing BP among adult participants aged 45 to 64 years once at baseline and followed them for over 35 years. We evaluated higher and lower supine and standing systolic BP, diastolic BP, mean arterial pressure, pulse pressure, absolute and relative orthostatic changes in BP after standing, and mean BP across positions. Associations with adjudicated coronary heart disease and mortality events, as well as hospitalizations and medical claims-based falls and syncope, were assessed via adjusted Cox models in strata of antihypertensive treatment.

resultsAmong 11 386 participants (mean age, 54 years [SD, 5.7 years]; 56% female; 25% Black adults), drops in systolic BP upon standing (absolute or relative) were associated with coronary heart disease, syncope, and mortality. Higher supine systolic BP and mean arterial pressure were associated with syncope among untreated participants. Increases in systolic BP ≥20 mm Hg upon standing were associated with falls (hazard ratio, 1.52 [95% CI, 1.14-2.02]) and syncope (hazard ratio, 1.40 [95% CI, 1.03-1.92]), particularly among untreated participants. Lower standing systolic BP was associated with a higher risk of syncope among treated participants (hazard ratio, 1.55 [95% CI, 1.14-2.12]). Regardless of treatment status, a higher pulse pressure was associated with coronary heart disease and mortality, but this was not observed for falls or syncope.

conclusionsHigher BP, rather than lower standing BP alone, may be an important risk factor for both cardiovascular and hypotension-related events, especially among untreated adults.