Table 4.

Multiple regression analysis with excreted water as dependent variable during urine diluting test.

Independent variables	B	SE	β	t	P
P-AVP (pmol/l)	5.184	5.844	0.154	0.887	0.381
U-c-AMP (pmol/l)	-0.002	0.003	-0.93	-0.586	0.562
U-AQP2 (ng/ml)	-13.270	8.415	-0.242	-1.577	0.123
SBP (mm Hg)	0.035	0.472	0.015	0.075	0.940
DBP (mm Hg)	-0.366	0.721	-0.105	-0.507	0.615
E-GFR (ml/min)	0.487	0.159	0.613	3.066	0.004

The amount of water excreted during the first four hours after water loading in percent of the given water load during the urine diluting test (20 ml/kg/body weight) as dependent variable and plasma concentration of vasopressin (p-AVP), urinary excretions of cyclic AMP (u-c-AMP) and aquaporin2 (AQP2), 24 hours systolic and diastolic blood pressure (SBP and DBP), and estimated GFR (e-GFR) as independent variables in a multiple regression analysis at the start of the urine diluting test in the whole study population (n = 41) comprising healthy control subjects (n = 10) and patients with chronic kidney disease or hypertension (n = 31; Group 2 (n = 14), e-GFR ≥ 90 ml/min; Group 3 (n = 11), 60 ml/min ≤ e-GFR < 90 ml/min; and Group 4 (n = 16), 15 ml/min < e-GFR ≤ 60 ml/min).

Unstandardized partial regression coefficients (Β), standard error (SE), standardized partial regression coefficient (β), t- value (t), and significance (P)