UDCA (n = 304) Placebo (n = 300) Adjusted effects estimate (95% CI), p value
Interaction test
Bile acid concentration, all women, N 256 247
Bile acid concentration (μmol/L), geometric mean (SD)
22.8 (2.4)
19.0 (2.8)
GMR 1.17 (1.00 to 1.36) p = 0.045
Baseline bile acid conc. <40 μmol/L, N 196 191 p = 0.647
Bile acid concentration (μmol/L), geometric mean (SD)
19.1 (2.3)
16.0 (2.6)
GMR 1.19 (1.00 to 1.41) p = 0.047
Baseline bile acid conc. ≥40 μmol/L, N 60 56
Bile acid concentration (μmol/L), geometric mean (SD)
40.6 (2.2)
34.5 (2.9)
GMR 1.13 (0.81 to 1.58) p = 0.466
Baseline bile acid conc. <100 μmol/L, N 236 233 p = 0.458
Bile acid concentration (μmol/L), geometric mean (SD)
21.3 (2.3)
17.8 (2.7)
GMR 1.19 (1.02 to 1.39) p = 0.031
Baseline bile acid conc. ≥100 μmol/L, N 20 14
Bile acid concentration (μmol/L), geometric mean (SD)
49.6 (2.5)
56.8 (3.2)
GMR 0.97 (0.48 to 1.96) p = 0.941
Itch score, all women, N 241 227
Itch score (mm), mean (SD)
49.8 (25.8)
56.6 (26.8)
MD -5.26 (-9.48 to -1.03) p = 0.015
Baseline itch score <60 mm, N 108 90 p = 0.640
Itch score (mm), mean (SD)
39.9 (23.9)
43.3 (23.6)
MD -4.04 (-10.33 to 2.26) p = 0.211
Baseline itch score ≥60 mm, N 133 137
Itch score (mm), mean (SD)
57.9 (24.6)
65.4 (25.1)
MD -6.00 (-11.73 to -0.28) p = 0.041
Baseline bile acid conc. <40 μmol/L, N 187 178 p = 0.455
Itch score (mm), mean (SD)
49.6 (25.6)
54.9 (26.5)
MD -4.41 (-9.13 to 0.30) p = 0.067
Baseline bile acid conc. ≥40 μmol/L, N 54 49
Itch score (mm), mean (SD)
50.4 (26.8)
62.8 (27.1)
MD -8.03 (-17.68 to 1.62) p = 0.106
Baseline bile acid conc. <100 μmol/L, N 226 216 p = 0.753
Itch score (mm), mean (SD)
49.9 (25.6)
56.3 (26.5)
MD -5.37 (-9.63 to -1.10) p = 0.014
Baseline bile acid conc. ≥100 μmol/L, N 15 11
Itch score (mm), mean (SD)
48.7 (29.6)
63.1 (31.8)
MD -5.77 (-34.12 to 22.57) p = 0.693