Table 6.

Estimated coefficients and P values from the total-charges linear regression

Variableaβ-CoefficientStandard ErrorP Value
aThe reference group was male patients <30 yr of age with CKD but neither diabetes mellitus nor hypertension and with Cr levels of <2.0 mg/dl.
Intercept3.5680.1810.0001
Age of 30 to 39 yr1.9640.2560.0001
Age of 40 to 49 yr2.2510.2250.0001
Age of 50 to 59 yr2.4620.2160.0001
Age of 60 to 64 yr2.2000.2350.0001
Age of ≥65 yr2.6330.1910.0001
Female gender-0.0140.0650.8315
Diabetes mellitus only0.8510.1830.0001
Hypertension only0.5110.0870.0001
Both diabetes mellitus and hypertension0.9630.1010.0001
Cr level of 2.0 to 2.9 mg/dl0.1130.0870.1951
Cr level of 3.0 to 3.9 mg/dl0.7360.1830.0001
Cr level of ≥4.0 mg/dl1.1570.1340.0001