Table 2.

Cox regression analysis of hypophosphatemia versus graft failure risk

Graft Failure (181 Events)Hypophosphatemia Category, HR [95% CI]Lowest Serum Phosphate per 1 mg/dl
AbsentMildSevereHR [95% CI]P Value
CrudeReference0.52 [0.36 to 0.77]a0.44 [0.30 to 0.64]b0.43 [0.33 to 0.56]<0.001
Model 1Reference0.55 [0.38 to 0.82]a0.46 [0.31 to 0.68]b0.46 [0.35 to 0.59]<0.001
Model 2Reference0.63 [0.42 to 0.92]c0.61 [0.41 to 0.91]c0.52 [0.39 to 0.68]<0.001
Model 3Reference0.82 [0.51 to 1.34]0.72 [0.43 to 1.19]0.56 [0.40 to 0.79]0.001
Model 4Reference0.87 [0.51 to 1.48]0.72 [0.42 to 1.26]0.60 [0.42 to 0.85]0.004
Model 5Reference0.79 [0.46 to 1.38]0.74 [0.42 to 1.29]0.65 [0.46 to 0.92]0.02
Model 6Reference0.79 [0.45 to 1.38]0.70 [0.40 to 1.25]0.60 [0.42 to 0.86]0.007
  • Model 1: adjusted for recipient age and sex. Model 2: model 1 plus eGFR at the time of lowest phosphate. Model 3: model 2 plus donor age and sex, donor type, cold ischemia time, delayed graft function, and proteinuria (at the time of the lowest serum phosphate). Model 4: model 3 plus total number of HLA mismatches, acute rejection, induction and maintenance immunosuppressive use, and panel of reactive antibodies. Model 5: model 4 plus cardiovascular risk factors (dialysis vintage, smoking status, pretransplant diabetes mellitus, and cardiovascular history). Model 6: model 5 plus phosphate supplementation, vitamin D supplementation, vitamin D supplementation pretransplantation, and corrected calcium concentrations (before transplantation and at the time of the lowest serum phosphate). HR, hazard ratio; 95% CI, 95% confidence interval.

  • a P<0.01.

  • b P<0.001.

  • c P<0.05.