Table 6.

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

Variable^a	β-Coefficient	Standard Error	P 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.
Intercept	3.568	0.181	0.0001
Age of 30 to 39 yr	1.964	0.256	0.0001
Age of 40 to 49 yr	2.251	0.225	0.0001
Age of 50 to 59 yr	2.462	0.216	0.0001
Age of 60 to 64 yr	2.200	0.235	0.0001
Age of ≥65 yr	2.633	0.191	0.0001
Female gender	-0.014	0.065	0.8315
Diabetes mellitus only	0.851	0.183	0.0001
Hypertension only	0.511	0.087	0.0001
Both diabetes mellitus and hypertension	0.963	0.101	0.0001
Cr level of 2.0 to 2.9 mg/dl	0.113	0.087	0.1951
Cr level of 3.0 to 3.9 mg/dl	0.736	0.183	0.0001
Cr level of ≥4.0 mg/dl	1.157	0.134	0.0001