Objective: We investigated cardiac and vascular remodeling in an unselected older population with either diastolic hypertension (HTN) or isolated systolic hypertension (ISH).
Background: Isolated systolic hypertension accounts for a substantial proportion of hypertension in individuals older than 65 years and is strongly associated with an increased risk of cardiac and cerebrovascular events. The exact mechanisms underlying the increased risk associated with ISH and elevated pulse pressure (PP), in comparison with HTN, have not been extensively investigated.
Methods: Community-dwelling residents age >/=65 years in a small town in Italy (Dicomano) were enrolled. Untreated subjects considered in this study included 173 normotensive subjects (blood pressure [BP] <140/90 mm Hg), 95 subjects with HTN (diastolic BP >/=90 mm Hg), and 43 subjects with ISH (BP >/=160/<90 mm Hg). All subjects underwent extensive clinical examination, echocardiography, carotid ultrasonography, and carotid applanation tonometry.
Results: Subjects with ISH had higher left ventricular (LV) mass, which was independently related to PP but not to systolic or mean pressures. Both carotid wall cross-sectional area and vascular stiffness were greater in ISH patients than in HTN and normal subjects and were independently related to PP but not to systolic BP. In addition, ISH was associated with a higher prevalence of carotid plaque and more extensive carotid atherosclerosis.
Conclusions: In our community-based elderly population, individuals with ISH had higher prevalences of LV hypertrophy and carotid atherosclerosis than subjects with HTN despite lower mean BP. These findings provide potential pathophysiologic mechanisms underlying the associations of ISH and PP with increased risk of cardiovascular morbidity and mortality.