Rosuvastatin potentiates the thyrotropin‐lowering effect of metformin in men with non‐autoimmune subclinical hypothyroidism and prediabetes

Abstract

What is known and objective: Metformin treatment decreases thyrotropin levels in individuals with hypothyroidism and this effect seems to be mediated by the 5 0adenosine monophosphate-activated protein kinase pathway in the pituitary. The activity of this pathway is also stimulated by statins. The current study was aimed at investigating whether the impact of metformin on hypothalamic-pituitary-thyroid axis activity is affected by statin use. Methods:The study included three matched groups of men with non-autoimmune hypothyroidism and prediabetes: patients treated for at least 6 months with highintensity rosuvastatin therapy (20-40 mg daily) [groups A (n = 24) and C (n = 19)] and men not receiving statin therapy [group B (n = 24)]. Over the entire study period (6 months), groups A and B received metformin (2.55-3 g daily). Moreover, groups A and C continued rosuvastatin therapy. The lipid profile, glucose homeostasis markers, and plasma concentrations of thyrotropin, total and free thyroid hormones, prolactin, FSH, LH, ACTH and insulin-like growth factor-1 were determined at baseline and 6 months later.