It's about Time

It is widely accepted that chronic kidney disease (CKD) associates with accelerated cardiovascular disease and a higher rate of death than would occur otherwise.1 These associations are based on studies of patients who had low renal function identified at a single point in time or, at most, two measurements separated by 3 mo to confirm chronicity. When caring for patients with CKD, we, too, generally estimate risk on the basis of single time point measurements of renal function. For example, a 65-yr-old man with a GFR of 80 ml/min per 1.73 m2 has an estimated risk for death of 12% during the subsequent 5 yr; however, if his GFR is 40 ml/min per 1.73 m2, then this risk is at least doubled.1In this issue of JASN , Shlipak et al. …