Table 1.

Definition of cutting points used to obtain three subcategories in covariatesa

ParameterLowest 33%Middle 33%Highest 33%
aBMI, body mass index; LBM, lean body mass; ECW, extracellular water; ICW, intracellular water.
bCalculated as TBW measured by deuterium isotope dilution divided by LBM measured by dual energy x-ray absorptiometry.
cECW measured by bromide isotope dilution; ICW calculated as TBW minus ECW (both TBW and ECW measured by isotope dilution).
Age (yr)≤45.045.0 to 57.0>57.0
BMI (kg/m2)≤22.522.5 to 26.0>26.0
Waist-to-hip ratio≤0.830.83 to 0.93>0.93
Hydration status LBM (L/kg)b≤0.69000.6900 to 0.7292>0.7292
Ratio ECW to ICWc≤0.76510.7651 to 0.8950>0.8950
Creatinine clearance (ml/min)≤50.7650.76 to 70.50>70.50