After adjustment for established risk factors including estimated glomerular filtration rate , an elevated SDMA-level ( 4th quartile , > 1.38 mol/L ) was associated with renal graft loss ; hazard ratio ( HR ) , 5.51 ; 95 % confidence interval ( CI ) , 1.95-15 .57 ; P = 0.001 , compared to the 1st quartile .