The influence of hyperprolactinemia on coagulation parameters in females with prolactinomas

Currently there is little information on the effects of prolactin (PRL) on the coagulation and fibrinolytic systems.

The aim of this study was to evaluate the effects of hypeprolactinemia on the parameters of the hemostatic system and activation of the coagulation system.

We studied PRL levels, body mass index (BMI), values of activated partial thromboplastin time (aPTT), prothrombin time (PT), thrombin time (TT), D-dimer level, von Willebrand factor antigen (vWFAg) and fibrinogen in 15 young female patients with microprolactinomas before and after therapy and in 15 healthy female controls.

As expected, pretreatment PRL levels were significantly higher in patients than in controls (140.90 +/- 42.87 vs. 12.53 +/- 4.05 ng/ml; p < 0.001). PT, although still in the normal range, was prolonged in patients with hyperprolactinemia as compared to the control group (13.53 +/- 1.39 vs. 12.65 +/- 0.53 s; p = 0.03) and normalized after therapy (12.69 +/- 0.65 vs. 12.65 +/- 0.53 s; p = 0.88). TT, although in normal range, was significantly shorter in the hypeprolactinemic patients than in the controls (14.34 +/- 4.52 vs. 17.21 +/- 1.35 s; p < 0.025) and after treatment remained significantly shorter than in the controls (15.17 +/- 1.55 vs. 17.21 +/- 1.35 s; p < 0.0001). D-dimer values before treatment in the patients with hyperproplactinemia were above the normal range (239.47 +/- 107.93 vs. 131.27 +/- 50.64 ng/ml, p = 0.002) and decreased to normal values after therapy (239.47 +/- 107.93 vs. 146.60 +/- 39.15 ng/ml; p < 0.001). D-dimer levels correlated with PRL (r = 0.30) and the change in serum D-dimer values significantly correlated with the change in PRL levels during therapy (r = 0.62). aPTT, vWFAg and fibrinogen were similar in patients and controls.

In our study, increased thrombin generation that resulted in elevated D-dimer levels may be one of the contributing factors to the prethrombotic state in patients with hyperprolactinemia.