title: Longitudinal Assessment of Serum Creatinine Levels on Graft Survival After Renal Transplantation: Joint Modeling Approach.
abstract: BACKGROUND
  Chronic kidney disease (CKD) is a major public health problem. The eventual outcome of CKD is end-stage renal disease (ESRD). Early diagnosis and proper management play an important role in preventing CKD progression to ESRD. Dialysis and kidney transplantation are the only treatment options available for patients suffering from ESRD.
  
  
  OBJECTIVE
  This study was designed to investigate the etiological role of recipient and donor characteristics on serum creatinine changes within the follow-up period, graft failure risk, and the impact of longitudinal serum creatinine levels on graft survival after renal transplantation.
  
  
  METHODS
  This study was carried out at the department of nephrology, Baqiyatallah hospital, Baqiyatallah University, Tehran, Iran, between April 2005 and December 2008. During that time period, 461 patients who had undergone renal transplantation were entered in the current study. Time to graft loss and serum creatinine levels at each visit were the primary data gathered for the study. A joint modeling of survival and longitudinal nonsurvival data was used to assess the association between the two processes and investigate the influential factors.
  
  
  RESULTS
  Median follow-up time was 6.80 months. A linear decreasing trend in serum creatinine level over time was found (P < 0.001). The results showed a positive correlation between serum creatinine levels and risk of graft failure (P < 0.001).
  
  
  CONCLUSIONS
  The major finding of this study is that one unit increase in serum creatinine level suggests an increased risk of graft failure of up to four times.
authors: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
authors: Elham
authors: E
authors: Maraghi
authors: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
authors: Abbas
authors: A
authors: Rahimi Foroushani
authors: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
authors: Shima
authors: S
authors: Younespour
authors: Nephrology and Urology Research Center, Baqiyatallah University of Medical Sciences, Tehran, IR Iran.
authors: Zohreh
authors: Z
authors: Rostami
authors: Nephrology and Urology Research Center, Baqiyatallah University of Medical Sciences, Tehran, IR Iran.
authors: Behzad
authors: B
authors: Einollahi
authors: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
authors: Mohammad Reza
authors: MR
authors: Eshraghian
authors: Department of Statistics, Mathematical Science and Computer Faculty, Shahid Chamran University, Ahvaz, IR Iran.
authors: Mohammad Reza
authors: MR
authors: Akhoond
authors: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
authors: Kazem
authors: K
authors: Mohammad
keywords: End Stage Renal Disease (ESRD); Graft Failure; Joint Modeling; Serum Creatinine