J-shaped curve for cardiovascular mortality: systolic or diastolic blood pressure?

Aggressive reduction of blood pressure (BP) may increase cardiovascular events (the J-curve phenomenon) in certain populations. There is a high number of available studies of antihypertensive treatment that provide strong evidence for J-shaped relationships between both diastolic and systolic BP and main cardiovascular outcomes. Nonetheless, most available studies were observational, and randomized trials might not have or lost their statistical power in post-hoc analysis. Contrariwise, most of prospective trial to demonstrate the benefits of intensive blood pressure control were inconclusive. Therefore, further studies are still necessary in order to clarify this issue.