title: Improvement of albuminuria after renal denervation.
abstract: OBJECTIVE
  The primary objective of this study was the effect of renal denervation (RDN) on elevated urinary albumin-to-creatinine ratio (UACR) in treatment-resistant hypertensive patients. In addition, patients were stratified according their UACR at baseline into micro- (30-300 mg/g, n=37) and macroalbuminuria (≥ 300 mg/g, <2,200 mg/g, n=22).
  
  
  BACKGROUND
  Increased albuminuria indicates cardiovascular and renal damage in hypertension. RDN emerged as an innovative interventional approach to reduce blood pressure (BP) and may thus reduce albumin urinary excretion.
  
  
  METHODS
  Fifty-nine treatment-resistant hypertensive patients with elevated UACR at baseline underwent catheter-based RDN using the Symplicity Flex™ catheter (Medtronic Inc., Santa Rosa, CA).
  
  
  RESULTS
  In the whole and pre-specified subgroups both office and 24-h ambulatory BP were significantly reduced 6 months after RDN. In parallel, a significant reduction in UACR occurred in all patients (160 (65-496) versus 89 (29-319) mg/g creatinine, p<0.001) and in both subgroups (microalbuminuria: 83 (49-153) versus 58 (17-113) mg/g creatinine, p=0.001; macroalbuminuria: (536 (434-1483) versus 478 (109-1080) mg/g creatinine, p<0.001). In accordance, the prevalence of micro- and macroalbuminuria decreased significantly. Regression analysis revealed a modest positive relationship between the decrease of UACR and the fall of systolic BP (β=0.340, p=0.039) independent of renal function. Renal function remained unchanged after RDN.
  
  
  CONCLUSIONS
  In summary, following RDN, the magnitude of albuminuria as well as the prevalence of micro- and macroalbuminuria decreased in treatment-resistant hypertensive patients. Since albuminuria is an independent renal and cardiovascular risk factor, our findings suggest a reduction of renal and cardiovascular risk in these patients.
authors.affiliation: Department of Nephrology and Hypertension, University of Erlangen-Nuremberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Ott
authors.affiliation: Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Mahfoud
authors.affiliation: Department of Radiology, University of Erlangen-Nuremberg, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Schmid
authors.affiliation: Department of Nephrology and Hypertension, University of Erlangen-Nuremberg, Germany.
authors.forename: Tilmann
authors.initials: T
authors.lastname: Ditting
authors.affiliation: Department of Nephrology and Hypertension, University of Erlangen-Nuremberg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Veelken
authors.affiliation: Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Ewen
authors.affiliation: Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Ukena
authors.affiliation: Department of Radiology, University of Erlangen-Nuremberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Uder
authors.affiliation: Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Böhm
authors.affiliation: Department of Nephrology and Hypertension, University of Erlangen-Nuremberg, Germany. Electronic address: roland.schmieder@uk-erlangen.de.
authors.forename: Roland E
authors.initials: RE
authors.lastname: Schmieder
mesh_terms: D000368:Aged; D000419:Albuminuria / Q000150:complications / Q000378:metabolism* / Q000601:surgery*; D001794:Blood Pressure; D017115:Catheter Ablation; D003404:Creatinine / Q000652:urine; D005260:Female; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000378:metabolism* / Q000601:surgery*; D007668:Kidney / Q000294:innervation* / Q000502:physiology; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013562:Sympathectomy / Q000379:methods*
chemical_list: D003404:Creatinine
keywords: Albuminuria; Blood pressure; Renal denervation; Renal organ damage; Treatment resistant hypertension; Urinary albumin-to-creatinine ratio