Dataset Information

Pulse pressure relation to aortic and left ventricular structure in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study.

ABSTRACT: High pulse pressure, a major cardiovascular risk factor, has been attributed to medial elastic fiber degeneration and aortic dilation, which transfers hemodynamic load to stiffer collagen. However, recent studies suggest higher pulse pressure is instead associated with smaller aortic diameter. Thus, we sought to elucidate relations of pulse pressure with aortic stiffness and aortic and cardiac dimensions. We used magnetic resonance imaging to examine relationships of pulse pressure with lumen area and wall stiffness and thickness in the thoracic aorta and left ventricular structure in 526 participants (72-94 years of age, 295 women) in the community-based Age, Gene/Environment Susceptibility-Reykjavik Study. In a multivariable model that adjusted for age, sex, height, weight, and standard vascular risk factors, central pulse pressure had a negative relationship with aortic lumen area (all effects expressed as mm Hg/SD; B=-8.1±1.2; P<0.001) and positive relationships with left ventricular end-diastolic volume (B=3.8±1.0; P<0.001), carotid-femoral pulse wave velocity (B=3.6±1.0; P<0.001), and aortic wall area (B=3.0±1.2; P=0.015). Higher pulse pressure in older people is associated with smaller aortic lumen area and greater aortic wall stiffness and thickness and left ventricular volume. Relationships of larger ventricular volume and smaller aortic lumen with higher pulse pressure suggest mismatch in hemodynamic load accommodation by the heart and aorta in older people.

SUBMITTER: Torjesen AA

PROVIDER: S-EPMC4162768 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Pulse pressure relation to aortic and left ventricular structure in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study.

Torjesen Alyssa A AA Sigurðsson Sigurður S Westenberg Jos J M JJ Gotal John D JD Bell Vanessa V Aspelund Thor T Launer Lenore J LJ de Roos Albert A Gudnason Vilmundur V Harris Tamara B TB Mitchell Gary F GF

Hypertension (Dallas, Tex. : 1979) 20140714 4

High pulse pressure, a major cardiovascular risk factor, has been attributed to medial elastic fiber degeneration and aortic dilation, which transfers hemodynamic load to stiffer collagen. However, recent studies suggest higher pulse pressure is instead associated with smaller aortic diameter. Thus, we sought to elucidate relations of pulse pressure with aortic stiffness and aortic and cardiac dimensions. We used magnetic resonance imaging to examine relationships of pulse pressure with lumen ar ...[more]

PMID: 25024287

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Project description:ObjectiveAge and high blood pressure are major risk factors for cerebral microbleeds (CMBs). However, the underlying mechanisms remain unclear and arterial stiffness may be important. We investigated whether carotid arterial stiffness is associated with incidence and location of CMBs.Approach and resultsIn the prospective, population-based Age, Gene/Environment Susceptibility (AGES)-Reykjavik study, 2512 participants aged 66 to 93 years underwent a baseline brain MRI examination and carotid ultrasound in 2002 to 2006 and returned for a repeat brain MRI in 2007 to 2011. Common carotid arterial stiffness was assessed using a standardized protocol and expressed as carotid arterial strain, distensibility coefficient, and Young elastic modulus. Modified Poisson regression was applied to relate carotid arterial stiffness parameters to CMB incidence. During a mean follow-up of 5.2 years, 463 people (18.4%) developed new CMBs, of whom 292 had CMBs restricted to lobar regions and 171 had CMBs in a deep or infratentorial region. After adjusting for age, sex, and follow-up interval, arterial stiffness measures were associated with incident CMBs (risk ratio per SD decrease in carotid arterial strain, 1.11 [95% confidence interval, 1.01-1.21]; per SD decrease in natural log-transformed distensibility coefficient, 1.14 [1.05-1.24]; and per SD increase in natural log-transformed Young elastic modulus, 1.13 [1.04-1.23]). These measures were also significantly associated with incident deep CMBs (1.18 [1.02-1.37]; 1.24 [1.08-1.42]; and 1.23 [1.07-1.42]) but not with lobar CMBs. When further adjusted for blood pressure and other baseline vascular risk factors, carotid plaque, prevalent CMBs, subcortical infarcts, and white matter hyperintensities, the associations persisted.ConclusionsOur findings support the hypothesis that localized increases in carotid arterial stiffness may contribute to the development of CMBs, especially in a deep location attributable to hypertension.

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Dataset Information

Pulse pressure relation to aortic and left ventricular structure in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study.

Publications

Pulse pressure relation to aortic and left ventricular structure in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study.

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