Author/Authors :
alimi, rasoul tehran university of medical sciences - school of public health - department of epidemiology and biostatistics, tehran, iran , hami, maryam mashhad university of medical sciences - kidney transplantation complications research center, ghaem hospital, school of medicine, mashhad, iran , afzalaghaee, monavar mashhad university of medical sciences - management social determinants of health research center, mashhad, iran , nazemian, fatemeh mashhad university of medical sciences - imam reza hospital - department of internal medicine, mashhad, iran , mahmoodi, mahmood tehran university of medical sciences - school of public health - department of epidemiology and biostatistics, tehran, iran , yaseri, mehdi tehran university of medical sciences - school of public health - department of epidemiology and biostatistics, tehran, iran , zeraati, hojjat tehran university of medical sciences - school of public health - department of epidemiology and biostatistics, tehran, iran
Abstract :
background: the performance of a transplanted kidney is evaluated by monitoring variations in the value of the most important markers. these markers are measured longitudinally, and their variation is influenced by other factors. the simultaneous use of these markers increases the predictive power of the analytical model. this study aimed to determine the simultaneous longitudinal effect of serum creatinine and blood urea nitrogen (bun) markers, and other risk factors on allograft survival after kidney transplantation. methods: in a retrospective cohort study, the medical records of 731 renal transplant patients, dated july 2000 to december 2013, from various transplant centers in mashhad (iran) were examined. univariate and multivariate joint models of longitudinal and survival data were used, and the results from both models were compared. the r package joinerml was used to implement joint models. p values 0.05 were considered statistically significant. results: results of the multivariate model showed that allograft rejection occurred more frequently in patients with elevated bun levels (hr=1.68, 95% ci: 1.24-2.27). in contrast, despite a positive correlation between serum creatinine and allograft rejection (hr=1.49, 95% ci: 0.99-2.22), this relationship was not statistically significant. conclusion: results of the multivariate model showed that longitudinal measurements of bun marker play a more important role in the investigation of the allograft rejection.
Keywords :
kidney transplantation , graft survival , survival analysis , longitudinal studies , multivariate analysis
