Is it the agent or the blood pressure level that matters for renal and vascular protection in chronic nephropathies?

Over the recent years, it has been clearly documented that hypertension and proteinuria are the major factors responsible for progression of chronic kidney disease (CKD). Therefore, a target BP of at least 130/80 mm Hg has been suggested in order to reduce the rate of progression and cardiovascular mortality. Some antihypertensive agents, such as ACE inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), and perhaps calcium channel blockers (CCBs), may also be capable of reducing CKD progression because they halt some of the pathogenetic mechanisms involved in renal damage, some of which is unrelated to reduction of proteinuria, per se. Although this specific effect seemed to be partially independent of blood pressure reduction, it remains controversial whether these drugs are really superior to other antihypertensive agents when blood pressure values recommended by guidelines are achieved. This issue is still a matter of debate because in published trials, target and achieved blood pressure values were constantly higher than those recommended today. Nevertheless, available findings seem to indicate that the renoprotective effect of these agents is at least partially independent of a better BP control. The only way to definitely solve this issue would be a new randomized trial. However, the clinical relevance of this trial is debatable, considering that we need all the drugs available to reach these recommended BP values.