Table 6.

Relationship between normalized biomarkers and htTKV, overall and by age

AnalytesPearson Correlation P Value Adjusted for Agea P Value Testing for Interactionb
All Patients (N=95)Age <43 (N=48)Age ≥43 (N=47)
Creatinine (µM)
Osmolality (mmol/kg)
Protein/creatinine ratio0.200.43d,e
Protein/osmolality ratio0.190.32c,d
Lactate/creatinine ratio0.
Lactate/osmolality ratio0.11−
Pyruvate/creatinine ratio−0.010.17−0.190.960.98
Pyruvate/osmolality ratio−0.010.06−0.070.990.20
Lactate/pyruvate ratio0.08−
Succinate/creatinine ratio−0.08−0.25−0.020.410.68
Succinate/osmolality ratio0.01−
cAMP/creatinine ratio−0.11−0.03−
cAMP/osmolality ratio−0.08−0.17−0.0040.430.22
PKM2/creatinine ratio0.28d,e 0.46d,e 0.110.006d 0.10
PKM2/osmolality ratio0.22c,d 0.41d,e 0.120.03d 0.10
PDK1/creatinine ratio−0.14−0.12−
PDK1/osmolality ratio−0.05−0.11−0.030.610.56
LDHA/creatinine ratio0.23c,d 0.32
LDHA/osmolality ratio0.22c,d 0.160.30c,d 0.04d 0.13
  • htTKV, height-adjusted total kidney volume; PKM2, pyruvate kinase M2; PDK1, pyruvate dehydrogenase kinase 1; LDHA, lactate dehydrogenase A.

  • a P value from multivariable regression analysis testing association between each biomarker and htTKV while adjusting for age.

  • b P value formally testing interaction by age: significant P value indicates there is evidence that the strength of the relationship between a biomarker and htTKV differs significantly depending on the patient’s age.

  • c Denotes Pearson correlation with P<0.05.

  • d Denotes significant P value.

  • e Denotes Pearson correlation with P<0.01.