Hyperprolactinemia is associated with abnormalities in glucose and lipid profile with development of insulin resistance and metabolic syndrome (MetS), which have been found to be improved by treatment with cabergoline (CAB). The current study aimed at investigating hormonal and metabolic effects of long-term CAB withdrawal in patients with prolactinomas. In 46 patients (37 F, 9 M, aged 34.5±11.5 yrs, 36 microadenomas and 10 macroadenomas) anthropometric (weight, BMI, waist circumference (WC)) and metabolic (fasting glucose (FG) and insulin (FI), total (TCHO), HDL and LDL cholesterol, triglycerides (TG), HOMA-IR, HOMA-β, ISI0, VAI, and prevalence of MetS) parameters, and PRL levels were evaluated at baseline, at CAB withdrawal (TWD), and 12 (T12) and 60 (T60) months after CAB discontinuation. CAB treatment (median duration=72 months) induced PRL normalization in all patients, and a significant improvement of BMI (P<0.0001), WC (P<0.0001), FI (P=0.007), HDL (P<0.001), LDL (P<0.001), HOMA-IR (P=0.012) and ISI0 (P=0.05) compared to baseline. CAB withdrawal resulted in prolonged and sustained normoprolactinemia, with only 8 (17.4%) patients requiring treatment restarting within 12 months. In 38 patients permanently discontinuing CAB, compared to TWD BMI (P<0.0001), WC (P<0.0001), TCHO (P<0.001) and VAI (P<0.0001) significantly impaired at T12, and similarly BMI (P<0.0001), WC (P<0.0001), TCHO (P<0.05) and VAI (P<0.0001) at T60. Compared to TWD no further changes were seen in FI, HOMA-IR, HOMA-β, ISI0. MetS prevalence significantly increases from T0 (23.9%) to T60 (41.3%, P<0.0001), with 8 patients (17.4%) developing MetS after CAB withdrawal. In conclusion, CAB discontinuation significantly worsens lipid profile and MetS prevalence in patients with prolactinomas.
20 - 23 May 2017
European Society of Endocrinology