Pulse pressure amplification, adiposity and metabolic syndrome in subjects under chronic antihypertensive therapy: The role of heart rate

Background Body mass index (BMI) and waist circumference (WC) are increased in subjects chronically treated for hypertension. However, the relationships of BMI, WC and metabolic syndrome (MS) with central wave reflections and pulse pressure (PP) amplification have never been investigated. Methods A cohort of 517 treated hypertensives was studied cross-sectionally as function of BMI, WC and presence of MS, the latter used as index of insulin resistance. In men and women, carotid wave reflections were evaluated using pulse wave analysis and augmentation index measurement. PP amplification between brachial and carotid arteries was determined as a vascular factor contributing to protect against an increased afterload. Results When compared to their own controls, treated hypertensive subjects with increased BMI, WC or MS did not differ in terms of mean values of brachial and carotid blood pressure and augmentation index. However, they were characterized by increased heart rate (HR) and PP amplification. Such results were independent of age, drug treatment, and traditional cardiovascular risk factors. After HR adjustment, the increased PP amplification observed in subjects with high WC or MS became non-significant in men, but remained unmodified in women. The presence of beta-blockade did not modify the result. Conclusion In treated hypertensive subjects, adiposity and insulin sensitivity influence independently PP amplification. The finding is observed mainly in women.