Table 2.
The effect of metformin on glucose homeostasis markers, plasma lipids and the investigated pituitary hormones in bromocriptine-treated patients and the control group
| Variable | Bromocriptine-treated patients with hyperprolactinaemia (Group A) | Bromocriptine-treated patients with normal prolactin levels (Group B) | Control group (Group C) | |
|---|---|---|---|---|
| Mean (SD) [∆ %] | Mean (SD) [∆ %] | Mean (SD) [∆ %] | ||
| Fasting glucose [mmol/L] | ||||
| Baseline | 4.81 (0.25) | 4.72 (0.23) | 4.77 (0.21) | |
| After 4 months | 4.56 (0.30) [−5] | 4.51 (0.24) [−4] | 4.58 (0.26) [−4] | |
| 2-h postchallenge plasma glucose [mmol/L] | ||||
| Baseline | 9.72 (0.63) | 9.17 (0.80) | 9.32 (0.70) | |
| After 4 months | 7.94 (0.56) [−18]&&& | 7.78 (0.52) [−15]&&& | 7.72 (0.76) [−17]&&& | |
| HOMA-IR | ||||
| Baseline | 5.0 (0.5) | 4.7 (0.4) | 4.6 (0.5) | |
| After 4 months | 3.4 (0.4) [−32]&&& | 3.1 (0.4) [−34]&&& | 3.2 (0.4) [−30]&&& | |
| Glycated haemoglobin [%] | ||||
| Baseline | 6.1 (0.2) | 6.0 (0.2) | 6.0 (0.2) | |
| After 4 months | 5.5 (0.2) [−10]&&& | 5.6 (0.2) [−7]&& | 5.5 (0.3) [−8]&& | |
| Total cholesterol [mmol/L] | ||||
| Baseline | 5.56 (0.61) | 5.62 (0.52) | 5.51 (0.58) | |
| After 4 months | 5.38 (0.58) [−3] | 5.34 (0.48) [−5] | 5.28 (0.51) [−4] | |
| LDL-cholesterol [mmol/L] | ||||
| Baseline | 3.31 (0.42) | 3.25 (0.32) | 3.19 (0.28) | |
| After 4 months | 3.16 (0.38) [−5] | 3.08 (0.29) [−5] | 3.01 (0.26) [−6] | |
| HDL-cholesterol [mmol/L] | ||||
| Baseline | 1.12 (0.18) | 1.25 (0.15) | 1.19 (0.16) | |
| After 4 months | 1.24 (0.16) [11] | 1.35 (0.18) [8] | 1.30 (0.14) [9] | |
| Triglycerides [mmol/L] | ||||
| Baseline | 2.56 (0.38) | 2.43 (0.35) | 2.40 (0.31) | |
| After 4 months | 2.16 (0.28) [−16]& | 2.06 (0.32) [−15]& | 2.08 (0.34) [−13]& | |
| Prolactin [ng/mL] | ||||
| Baseline | 46 (10)***### | 12 (4) | 14 (3) | |
| After 4 months | 34 (8) [−26]***###& | 11 (4) [−8] | 12 (3) [−14] | |
| IGF-1 [ng/mL] | ||||
| Baseline | 235 (61) | 195 (43) | 189 (41) | |
| After 4 months | 220 (62) [−6] | 185 (40) [−5] | 176 (29) [−7] | |
| Thyrotropin [mIU/L] | ||||
| Baseline | 2.0 (0.7) | 1.5 (0.4) | 1.4 (0.5) | |
| After 4 months | 1.6 (0.6) [−20] | 1.3 [−13] | 1.2 [−14] | |
Only data of individuals who completed the study were included in the final analyses
*** p < 0.001 versus control subjects (group C)
### p < 0.001 versus bromocriptine-treated patients with normal prolactin levels (group B)
& p < 0.05
&& p < 0.01
&&& p < 0.001 versus baseline value