Supraphysiological doses of GH induce rapid changes in cardiac morphology and function

• Published in: The journal of clinical endocrinology and metabolism 2002-04, Vol.87 (4), p.1654-1659
• Main Authors: CITTADINI, Antonio, BERGGREN, Annika, LONGOBARDI, Salvatore, EHRNBORG, Christer, NAPOLI, Raffaele, ROSEN, Thord, FAZIO, Serafino, CAIDAHL, Kenneth, BENGTSSON, Bengt-Ake, SACCA, Luigi
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Cardiac Output - drug effects; Dose-Response Relationship, Drug; Double-Blind Method; Echocardiography; Female; Functional investigation of endocrine glands and genital system; Growth Hormone - administration & dosage; Growth Hormone - pharmacology; Heart - anatomy & histology; Heart - drug effects; Heart - physiology; Hormones. Endocrine system; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Pharmacology. Drug treatments; Recombinant Proteins - administration & dosage; Recombinant Proteins - therapeutic use; Reference Values; Ventricular Remodeling
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.87.4.1654

GH is an agent widely used in sport to improve physical performance and has been proposed as adjunctive therapy in several clinical conditions. However, its short-term effects on the normal human heart are poorly understood. Sixty young normal volunteers (30 males and 30 females) were enrolled in a multicenter, double-blind, placebo-controlled study. All subjects were randomized to receive GH (0.03 or 0.06 mg/kg.d) or placebo. A complete Doppler-echocardiographic examination was performed at baseline and after 4 wk of treatment. Low-dose GH did not significantly affect echocardiographic parameters. In contrast, high-dose GH increased left ventricular mass index by 12% (P < 0.05). The type of growth response was concentric, because left ventricular wall thickness but not diameter increased, leading to a 10% increase of relative wall thickness. These structural changes were associated with functional changes, including a significant increase in cardiac index and a decrease in peripheral vascular resistance; diastolic function was not altered. Fractional shortening and systemic blood pressure were unchanged in the two treatment groups. In conclusion, administration of GH for 4 wk at doses that simulate GH abuse in sport caused a high cardiac output state associated with concentric left ventricular remodeling.