The ambulatory arterial stiffness index is not affected by night-time blood pressure characteristics

Ambulatory arterial stiffness index (AASI), a measure derived from ambulatory blood pressure (BP) measurements, is a marker of arterial stiffness and a predictor of cardiovascular mortality. Yet, AASI has been contested due to its dependence on the degree of the nocturnal BP reduction in hypertensive patients. Excluding night-time BP readings, and thus the dipping information, we demonstrate that daytime AASI remains elevated in hypertensive children and adults and maintains the relationship with age, pulse pressure and systolic or diastolic BP.