White matter hyperintensities in migraine: Clinical significance and central pulsatile hemodynamic correlates

Background The role of central pulsatile hemodynamics in the pathogenesis of white matter hyperintensities in migraine patients has not been clarified. Methods Sixty patients with migraine (20-50 years old; women, 68%) without overt vascular risk factors and 30 demographically-matched healthy controls were recruited prospectively. Cerebral white matter hyperintensities volume was determined by T1-weighted magnetic resonance imaging with CUBE-fluid-attenuated-inversion-recovery sequences. Central systolic blood pressure, carotid-femoral pulse wave velocity, and carotid augmentation index were measured by applanation tonometry. Carotid pulsatility index was derived from Doppler ultrasound carotid artery flow analysis. Results Compared to the controls, the migraine patients had higher white matter hyperintensities frequency (odds ratio, 2.75; p=0.04) and greater mean white matter hyperintensities volume (0.174 vs. 0.049, cm(3), p=0.04). Multivariable regression analysis showed that white matter hyperintensities volume in migraine patients was positively associated with central systolic blood pressure (p=0.04) and carotid-femoral pulse wave velocity (p<0.001), but negatively associated with carotid pulsatility index (p=0.04) after controlling for potential confounding factors. The interaction effects observed indicated that the influence of carotid-femoral pulse wave velocity (p=0.004) and central systolic blood pressure (p=0.03) on white matter hyperintensities formation was greater for the lower-carotid pulsatility index subgroup of migraine patients. White matter hyperintensities volume in migraine patients increased with decreasing carotid pulsatility index and with increasing central systolic blood pressure or carotid-femoral pulse wave velocity. Conclusions White matter hyperintensities are more common in patients with migraine than in healthy controls. Increased aortic stiffness or central systolic blood pressure in the presence of low intracranial artery resistance may predispose patients with migraine to white matter hyperintensities formation.