Objective: The ambulatory arterial stiffness index (AASI) can be computed from individual 24-h blood pressure recordings.
Methods: We investigated the prognostic value of AASI and 24-h pulse pressure in a random sample of 1829 Danes, aged 40-70 years. We adjusted for sex, age, body mass index, mean arterial pressure, smoking, diabetes, ratio of total to high-density lipoprotein cholesterol, and history of cardiovascular disease with Cox regression.
Results: Over a median follow-up of 9.4 years, incidences of fatal and nonfatal endpoints were 40 for stroke, 150 for coronary heart disease, and 212 for cardiovascular events. In fully adjusted models, the hazard ratios associated with 1 SD increase (0.14 U) in the AASI were 1.62 (95% confidence interval, 1.14-2.28; P = 0.007) for stroke, 0.96 (0.80-1.14; P = 0.62) for coronary heart disease, and 1.06 (0.91-1.23; P = 0.49) for cardiovascular events. None of these ratios reached significance for pulse pressure (P > 0.47). The AASI still predicted stroke after excluding individuals with previous cardiovascular disease or after adjustment for systolic and/or diastolic blood pressure instead of mean arterial pressure.
Conclusions: In a randomly recruited European population, the AASI was a strong predictor of stroke, beyond traditional cardiovascular risk factors, including the mean arterial pressure and pulse pressure.