Annual decline in estimated glomerular filtration rate is a risk factor for cardiovascular events independent of proteinuria.

AIMS: Chronic kidney disease is a risk factor of the development of cardiovascular disease (CVD). However, it is not clear whether decline of glomerular filtration rate (GFR), not reduced GFR, is a risk factor for the incidence of CVD independent of proteinuria. METHODS: By using a population-based 521 123 person-years longitudinal cohort receiving annual health checkups from 2008 to 2010, we examined whether the annual decline of estimated GFR is a risk factor for CVD development independent of proteinuria. RESULTS: During the follow-up period, there were 12 041 newly developed CVD events, comprising 4426 stroke events and/or 8298 cardiac events. As expected, both reduced estimated GFR and proteinuria were risk factors for the development of CVD in our study population. Moreover, annual decline of estimated GFR was a significant and independent risk factor for the incidence of CVD (HR [95% CI], 1.23 [1.18-1.28] in males or 1.14 [1.10-1.18] in females for -10% per year) with covariant adjustment for proteinuria and reduced estimated GFR. CONCLUSION: Annual decline of GFR is an independent risk factor for CVD. Serial measurement of both creatinine and proteinuria would be better to predict the incidence of CVD in the general population.

Annual incidence of persistent proteinuria in the general population from Ibaraki annual urinalysis study.

BACKGROUND: For a definitive diagnosis of chronic kidney disease, at least 2 consecutive positive results of proteinuria with an interval of >3 months are required. However, most previous reports were based on single-screening data. PATIENTS AND METHODS: The subjects in this study were participants in an annual health examination held in Ibaraki, Japan, between 1993 and 2003. The follow-up duration with serial urinalysis for 3 years of patients who were negative for proteinuria in the initial year was 330,614 person-years in males and 687,381 person-years in females among 81,854 male and 155,256 female subjects. We evaluated the incidence and risk factor for the incidence of proteinuria and persistent proteinuria. RESULT: The annual incidence of proteinuria and persistent proteinuria was 1.31 and 0.33 % in males and 0.68 and 0.14 % in females. Among the subjects without hypertension and diabetes, the annual incidence was 0.81 and 0.16 % in males and 0.37 and 0.06 % in females, respectively. Risk analysis indicated that hypertension in males [hazard ratio (HR) 2.052] and females (2.477), diabetes in males (3.532) and females (3.534) and reduced renal function in males (3.097) and females (2.827) were significant positive risks for development of persistent proteinuria. CONCLUSION: By annual urinalysis screening of the general population, 1 out of 303 male subjects and 1 out of 725 female subjects developed persistent proteinuria every year. Subjects with diabetes, hypertension and reduced renal function had a 2 or 3 times higher risk for the incidence of persistent proteinuria in both males and females.