title: Urine matrix metalloproteinase-7 and risk of kidney disease progression and mortality in type 2 diabetes.
abstract: OBJECTIVE
  The renin-angiotensin-aldosterone system (RAAS), bone morphogenetic protein (BMP) and WNT pathways are dysregulated in diabetic kidney disease (DKD). Urine excretion of angiotensinogen, gremlin-1 and matrix metalloproteinase-7 (MMP-7), components of the RAAS, BMP and WNT pathways, respectively, is increased in DKD. We asked if this increase is associated with subsequent progression to end-stage renal disease (ESRD) or death.
  
  
  METHODS
  Using time-to-event analyses, we examined the association of baseline urine concentration of these proteins with progression to ESRD or death in a predominantly Mexican-American cohort with type 2 diabetes and proteinuric DKD (n=141).
  
  
  RESULTS
  Progression to ESRD occurred for 38 participants over a median follow-up of 3.0years; 39 participants died over a median follow-up of 3.6years. Urine MMP-7 and gremlin-1 were associated with increased risk of ESRD after adjustment for demographic and clinical covariates. Angiotensinogen showed a U-shaped relationship with ESRD, with the middle tertile associated with lowest risk of ESRD. After additional adjustment for glomerular filtration rate and albuminuria, all associations with ESRD lost significance. Only urine MMP-7 was associated with mortality, and this association remained robust in the fully adjusted model with a Hazard ratio of 3.59 (95% confidence interval 1.31 to 9.85) for highest vs. lowest tertile. Serum MMP-7 was not associated with mortality and did not attenuate the association of urine MMP-7 with mortality (HR 4.03 for highest vs. lowest urine MMP-7 tertile).
  
  
  CONCLUSIONS
  Among people with type 2 diabetes and proteinuric DKD, urine MMP-7 concentration was strongly associated with subsequent mortality.
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA. Electronic address: afkarian@u.washington.ed.
authors.forename: Maryam
authors.initials: M
authors.lastname: Afkarian
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA; Department of Biostatistics, University of Washington.
authors.forename: Leila R
authors.initials: LR
authors.lastname: Zelnick
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA.
authors.forename: John
authors.initials: J
authors.lastname: Ruzinski
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA.
authors.forename: Bryan
authors.initials: B
authors.lastname: Kestenbaum
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Himmelfarb
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA.
authors.forename: Ian H
authors.initials: IH
authors.lastname: de Boer
authors.affiliation: Kidney Research Institute and Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA.
authors.forename: Rajnish
authors.initials: R
authors.lastname: Mehrotra
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000208:ethnology / Q000401:mortality / Q000652:urine; D003928:Diabetic Nephropathies / Q000150:complications / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006779:Hospitals, Public; D006786:Hospitals, Urban; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007676:Kidney Failure, Chronic / Q000150:complications / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D020783:Matrix Metalloproteinase 7 / Q000652:urine*; D017058:Mexican Americans; D008875:Middle Aged; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000150:complications / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D012306:Risk; D015854:Up-Regulation
chemical_list: C060932:MMP7 protein, human; D020783:Matrix Metalloproteinase 7
keywords: Angiotensinogen; Diabetic kidney disease; Gremlin-1; MMP-7; Mortality; Type 2 diabetes