Little is known about the potential progression of hypertensive patients towards isolated systolic hypertension (ISH) and about the phenotypes associated with the development of this condition. Aim of this study was to detect predictors of evolution towards ISH in patients with initial systolic-diastolic hypertension. We selected 7801 hypertensive patients free of prevalent cardiovascular (CV) diseases or severe chronic kidney disease and with at least 6-month follow-up from the Campania Salute Network. During 55±44 months of follow-up, incidence of ISH was 21%. Patients with ISH at the follow-up were significantly older (P0.05). Our findings suggest that ISH is a sign of aggravation of the atherosclerotic disease already evident by the target organ damage. Great efforts should be paid to prevent this evolution and prompt aggressive therapy for arterial hypertension should be issued before the onset of target organ damage, to reduce global CV risk.