title: Different association between renal hyperfiltration and mortality by sex.
abstract: OBJECTIVE
  Renal hyperfiltration (RHF) is a marker of early kidney injury that was recently shown to be a novel marker of mortality. However, it has no clear definition. In this study, we suggested an age- and sex-adjusted RHF definition and explored the association between RHF and mortality by sex.
  
  
  METHODS
  We analyzed data from individuals receiving routine health examinations from 1995 to 2009. RHF was defined as an estimated glomerular filtration rate over the 95th percentile matched for age and sex.
  
  
  RESULTS
  A total of 114 966 individuals were included. During the 75-month of observation period, 2559 (2.2%) participants died. Among those, 71.4% were men. Because sex and RHF had a significant interaction for mortality (P for interaction < 0.001), we performed survival analysis according to sex. RHF was related to lower body weight and a higher proportion of cigarette smoking in men, whereas these relationships were not found in women. In the Kaplan-Meier curve, RHF was associated with higher mortality rate than non-RHF in both sexes, but this relationship was more prominent in men. In the multivariate analysis, RHF remained as an independent risk factor for all-cause mortality even after adjustment for confounding in men (hazard ratio, 1.34; 95% confidence interval, 1.12-1.59; P = 0.001). In women, RHF was not associated with increased mortality.
  
  
  CONCLUSIONS
  We demonstrated that RHF was a significant risk factor for mortality in men but not in women. The mechanisms and clinical implications of these different associations according to sex require a further clarification.
authors.affiliation: Department of Internal Medicine, Dongguk University Medical Center, Gyeongju, Korea.
authors.forename: Kyung Don
authors.initials: KD
authors.lastname: Yoo
authors.affiliation: Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyung-Jin
authors.initials: HJ
authors.lastname: Yoon
authors.affiliation: Department of Social and Preventive Medicine, Inha University College of Medicine, Incheon, Korea.
authors.forename: Seung-Sik
authors.initials: SS
authors.lastname: Hwang
authors.affiliation: Department of Internal Medicine, Healthcare System Gangnam Center Seoul National University Hospital, Seoul, Korea.
authors.forename: Nam Ju
authors.initials: NJ
authors.lastname: Heo
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.|Kidney Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Ho Jun
authors.initials: HJ
authors.lastname: Chin
authors.affiliation: Kidney Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Yang
authors.affiliation: Kidney Research Institute, Seoul National University Hospital, Seoul, Korea.|Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Kwon Wook
authors.initials: KW
authors.lastname: Joo
authors.affiliation: Kidney Research Institute, Seoul National University Hospital, Seoul, Korea.|Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Yon Su
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Kidney Research Institute, Seoul National University Hospital, Seoul, Korea.|Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Hajeong
authors.initials: H
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology*; D007674:Kidney Diseases / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors
keywords: Mortality; Renal hyperfiltration; Sex