Table 3.
Plasma concentration of vasopressin (p-AVP) and plasma osmolaririty (p-osm) during urine diluting test.
| Baseline | Post 0-60 |
Post 60-120 |
Post 120-180 |
Post 180-240 |
Post 240-300 |
P (GLM-within) |
|
|---|---|---|---|---|---|---|---|
|
AVP (pmol/l) | |||||||
| Group 1 |
1.00(0.40) |
0.7(0.10) * |
0.60(0.25)* |
0.70(0.35)* |
0.90(0.65) |
1.00(0.45) |
0.000 |
| Group 2 |
0.75(0.45) |
0.60(0.08)* |
0.60(0.18)* |
0.60(0.10)* |
0.70(0.60) |
0.80(0.45) |
|
| Group 3 |
0.70(0.53) |
0.60(0.08)* |
0.60(0.15)* |
0.60(0.15)* |
0.65(0.63) |
0.80(0.60) |
|
| Group 4 |
1.80(1.85) |
1.10(0.83)* |
1.10(0.88)* |
1.30(0.93)* |
1.50(0.85)* |
1.65(1.25)* |
|
| P (GLM-between) |
0.000 |
||||||
| P (Kruskal-Wallis) |
0.000 |
0.000 |
0.000 |
0.000 |
0.001 |
0.002 |
|
|
P-osm (mosmol/l) | |||||||
| Group 1 |
290(6) |
283(3) * |
284(6)* |
287(5)* |
286(5)* |
287(4) |
0.000 |
| Group 2 |
288(7) |
283(8)* |
284(8)* |
286(9)* |
286(9)* |
288(8) |
|
| Group 3 |
291(11) |
285(7)* |
287(9)* |
289(6)* |
288(4)* |
289(6)* |
|
| Group 4 |
305(14) |
299(15)* |
298(14)* |
297(14)* |
297(14)* |
299(13)* |
|
| P (GLM-between) |
0.000 |
||||||
| P (Kruskal-Wallis) | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |
Blood samples were drawn after a baseline period of 120 minutes, and after the end of five consecutive periods each of one hour duration (Post 0-60, Post 60-120, Post 120-180, Post 180-240, and Post 240-300. An oral water load of 20 ml/kg body weight was given during the first 15 minutes of the Post 0-60 period. Group 1 comprised healthy control subjects (n = 10). Groups 2-4 comprised patients with chronic kidney disease or hyperension (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).
Median with Interquartile Range in brackets. A General Linear Model (GLM) for Repeated Measures was used for comparison within and between groups. Kruskal-Wallis's test was used to analyze differences between groups during the diluting test. Wilcoxon's signed rank test was used in each group to analyze significant deviations from baseline (* = P < 0.05).