Relations of Arterial Stiffness With Postural Change in Mean Arterial Pressure in Middle-Aged Adults

Abstract

Impaired regulation of blood pressure on standing can lead to adverse outcomes, including falls, syncope, and disorientation. Mean arterial pressure (MAP) typically increases on standing; however, an insufficient increase or a decline in MAP on standing may result in decreased cerebral perfusion. Orthostatic hypotension has been reported in older people with increased arterial stiffness, whereas the association between orthostatic change in MAP and arterial stiffness in young- to middle-aged individuals has not been examined. We analyzed orthostatic blood pressure response and comprehensive hemodynamic data in 3205 participants (1693 [53%] women) in the Framingham Heart Study Third Generation cohort. Participants were predominantly middle aged (mean age: 46±9 years). Arterial stiffness was assessed using carotid–femoral pulse wave velocity, forward pressure wave amplitude, and characteristic impedance of the aorta. Adjusting for standard cardiovascular disease risk factors, orthostatic change in MAP (6.9±7.7 mm Hg) was inversely associated with carotid–femoral pulse wave velocity (partial correlation, r p =−0.084; P <0.0001), forward wave amplitude ( r p =−0.129; P <0.0001), and characteristic impedance ( r p =−0.094; P <0.0001). The negative relation between forward wave amplitude and change in MAP on standing was accentuated in women ( P =0.002 for sex interaction). Thus, higher aortic stiffness was associated with a blunted orthostatic increase in MAP, even in middle age. The clinical implications of these findings warrant further study.