Blood pressure control, which can induce a slight decrease in the glomerular filtration rate (GFR), plays a nephron- and cardioprotective role. However, the more important early decline in GFR associated with antihypertensive therapy and strict blood pressure targets is still of concern. Since few data are available from trials and observational studies, and the phenomenon is relatively rare, we performed a metaanalysis of available studies. We conclude that major reductions in the glomerular filtration rate occurring soon after starting angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and/or under intensive blood pressure control predict end-stage kidney disease