Gray matter volume in relation to cardio-vascular stiffness.

BACKGROUND

Hemodynamic disturbances are associated with aging as well as the chronic process of left ventricular and arterial stiffening. This process can influence gray matter volume and thereby contribute to brain atrophy. We performed a comprehensive assessment of left ventricular and arterial function as well as central hemodynamics. These data were correlated with gray matter volume (GMV) as evaluated by magnetic resonance imaging (MRI).

METHODS

GMV and aortic stiffness were estimated using MRI. Left ventricular end-systolic elastance or stiffness (Ees), arterial elastance (Ea) and total arterial compliance (TAC) were determined by echocardiography. Central hemodynamics were assessed using pulse wave analysis.

RESULTS

Seventy-five healthy subjects (42 women, 33 men, mean age of 58 years) were recruited. The clinical analyses showed that GMV correlates significantly and inversely with age (r=-0.37, P=0.001), end-systolic LV stiffness (r=-0.39, P=0.0009), augmentation pressure (r=-0.48, P<0.0001), arterial elastance (r=-0.27, P=0.02) and aortic stiffness (r=-0.23, P=0.04), as determined by aortic pulse wave velocity (aPWV). GMV correlated significantly with total arterial compliance (r=0.23, P=0.04). Stepwise forward multiple regression analysis revealed that 35% of variance (P<0.0001) in GMV is attributed to aPWV, Ees and AP.

CONCLUSIONS

Left ventricular end-systolic stiffness, augmentation of central arterial pressure and aortic stiffness are associated independently and negatively with GMV. These associations suggested that brain atrophy is influenced by hemodynamic factors.