Orthostatic blood pressure response, carotid intima-media thickness, and plasma fibrinogen in older nondiabetic adults.

OBJECTIVE: Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension (OHTN) independently predict cardiovascular events, the underlying mechanisms are still debatable.
METHODS: A total of 700 nondiabetic adults (43% men, age 64 years) were examined by orthostatic blood pressure (BP) test, carotid artery ultrasonography, and biochemical tests including plasma fibrinogen and lipid profile. Multivariate-adjusted logistic regression was applied to assess association of intima-media thickness (IMT) and P-fibrinogen with orthostatic hypotension and OHTN. In addition, distribution of IMT and P-fibrinogen across quintiles of orthostatic systolic BP (SBP) response was analyzed.
RESULTS: Orthostatic hypotension and OHTN were found in 40 (5.7%) and 45 (6.4%) study participants, respectively. Both IMT [odds ratio (OR), 95% confidence interval (CI) per one-SD increment: 1.27, 1.01-1.60; P = 0.04] and P-fibrinogen (OR 1.44, 1.07-1.93; P = 0.02) were associated with orthostatic hypotension in a crude model. After adjustment relationship between orthostatic hypotension and IMT was slightly attenuated (OR 1.26, 0.96-1.65; P = 0.09) but was substantially unchanged in regard to P-fibrinogen (OR 1.45, 1.06-1.99; P = 0.02). In contrast, OHTN showed no association with either IMT or P-fibrinogen (adjusted OR 1.09, 0.78-1.52; P = 0.61, and 0.97, 0.70-1.34; P = 0.84, respectively). Distribution of IMT across quintiles of orthostatic SBP response was U-shaped, whereas that of fibrinogen was more linear but none of borderline quintiles (with pronounced hypertensive or hypotensive response) significantly differed from the middle quintiles in a fully adjusted model.
CONCLUSION: In older nondiabetic adults only orthostatic hypotension seems to independently correlate with increased carotid atherosclerosis and systemic inflammation.