Abstract
Recently, changes in urinary albumin and in GFR have been recognized as risk factors for the development of end-stage kidney disease and mortality. Though most clinical epidemiology studies of chronic kidney disease (CKD) used renal function and proteinuria at baseline alone, definitive diagnosis of CKD with multiple measurements intensifies the differences in the risk for mortality between the CKD and non-CKD populations. We hypothesized that a transient diagnosis of proteinuria and reduced renal function each indicate a significantly higher mortality compared to definitive non-CKD as the negative control and lower mortality compared with definitive CKD as the positive control. The present longitudinal study evaluated a general-population cohort of 338,094 persons who received annual health checkups, with a median 4.3-year study period. There were 2,481 deaths, including 510 CVD deaths (20.6%) and 1,328 cancer deaths (53.5%), and mortality risk was evaluated for transient proteinuria and for transiently reduced renal function. The hazard ratios (HRs) for all-cause mortality and cancer mortality were not significant, but that for cardiovascular mortality was significantly higher for transient proteinuria (HR, 1.94 [95% confidence interval, 1.27–2.96] in men and 2.78 [1.50–5.16] in women). On the other hand, transiently reduced renal function was not significant for either cardiovascular mortality risk or cancer mortality risk. We surmise that this is the first study of the mortality risk of transient dipstick proteinuria in a large general-population cohort with cause-specific death registration. Transiently positive proteinuria appears to be a significant risk specifically for cardiovascular mortality compared with definitely negative for proteinuria.
Highlights
Chronic kidney disease (CKD) is a risk factor for progression to end-stage kidney disease (ESKD), and the development of cardiovascular disease (CVD) and all-cause mortality [1,2,3,4,5,6,7]
One recent cross-sectional study of a CKD population with CVD (34.7%) and malignant neoplasms (31.8%) as the leading causes of death demonstrated that a decline in the estimated glomerular filtration rate was associated with a higher risk of death due to CVD, but not malignancy [8]
These results were not significant for various possible reasons, but they implied that a change in the amount of urinary albumin or protein might be associated with cause-specific death during follow-up
Summary
Chronic kidney disease (CKD) is a risk factor for progression to end-stage kidney disease (ESKD), and the development of cardiovascular disease (CVD) and all-cause mortality [1,2,3,4,5,6,7]. Another study of a general population showed a slightly higher overall cancer mortality in CKD patients compared with non-CKD patients (adjusted hazard ratio [HR] 1.20 with a 95% confidence interval [CI] of 1.01–1.42) [9]. These investigations did not take variations in renal function and proteinuria into consideration. It was found that a 4-fold decrease in ACR seemed to be associated with higher CVD mortality (HR [95% CI], 1.35 [0.93–1.95]), while the HR for non-CVD mortality was not higher (0.89 [0.67–1.18]) These results were not significant for various possible reasons, but they implied that a change in the amount of urinary albumin or protein might be associated with cause-specific death during follow-up
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
