Cho ME, Sweeney C, Fino N, et al. - Given that there may be physiologic significance of prorenin (a precursor of renin) and renin in CKD, however, their plasma levels have not been properly characterized in CKD, thus, researchers assessed distribution as well as longitudinal alterations of prorenin and renin levels in the plasma samples obtained at follow-up years 1, 2, 3, and 5 of the Chronic Renal Insufficiency Cohort study, which represents an ongoing longitudinal observational analysis of 3,939 adults suffering from CKD. At year 1, lower prorenin and renin values were detected in females and non-Hispanic blacks. Factors identified to be related to higher levels were: diabetes, lower estimated glomerular filtration rate, and use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statins, and diuretics. A reduction in prorenin and renin by a mean of 2 and 5% per year, respectively, was reported. In this study, cross-sectional clinical factors identified to be related to prorenin and renin values were similar. Over the years, a reduction was evident in both plasma prorenin and renin levels, especially in those suffering from severe CKD at study entry.