Modification of epicardial fat thickness in adult GHD patients after short-term replacement therapy with rhGH
Emanuele Ferrante1, Claudia Giavoli1, Alexis Malavazos2, Federica Ermetici2, Silvia Bergamaschi1, Cristina Ronchi1, Calin Coman3, Elena Passeri2, Sabrina Corbetta2, Andrea Lania1, Bruno Ambrosi2, Anna Spada1 & Paolo Beck-Peccoz1
Adult GH deficiency syndrome is characterized by visceral obesity, dyslipidemia, insulin resistance and is associated with an increased cardiovascular risk. Epicardial adipose tissue, giving its relationship with abdominal visceral adiposity, coronary artery disease, cardiac morphology and function and metabolic syndrome, has been proposed as cardio-metabolic risk indicator. In this study, we evaluated the echocardiographic epicardial fat thickness in 14 patients (8 M and 6 F, age 48±11.8 years, BMI 26.4±3.0 kg/m2) with adult onset GHD, before and after 12 months of rhGH therapy. Echocardiographic left ventricular diameter (LVD), interventricular septum thickness (IVS), left ventricular (LV) posterior wall thickness, LV mass (LVM) and left ventricular mass indexed (LVMi), E/A ratio, isovolumetric relaxation velocity (IRV) and deceleration time (DT) were measured. Anthropometric and metabolic parameters (BMI, BF% by DEXA, waist circumference, fasting glucose and insulin, HbA1c, lipid profile), indices of insulin sensitivity and QoL (through QLS-H Z-scores) were also evaluated. At baseline, IGF1 levels were low in all patients and epicardial fat thickness measured 7.6±2.0 mm. After 12 months of rhGH therapy (mean dose: 0.34±0.1 mg), IGF1 levels significantly rose (51.4±19.3 vs 129.5±54.3, P<0.05). Epicardial fat thickness significantly decreased (3.9±2.3 vs 7.6±2.0, P<0.05), as well as BF% (31.8±6.1 vs 35.2±6.3, P<0.05) and IRV (94.5±17.0 vs 112.8±23.3, P<0.05), suggesting an improvement in diastolic function. No other significant modifications in echocardiographic parameters were observed. QLS-H Z-scores increased from −1.75±0.9 at baseline to −1.0±1.3 after 1 year of GH treatment (P<0.05). BMI, waist circumference, fasting glucose and insulin, HbA1c, lipid profile, HOMA-IR and QUICKI values did not differ from baseline. In conclusion, epicardial fat thickness, a marker of cardio-metabolic risk, significantly decreases after 1 year of rhGH therapy. These data suggest that this measurement is a useful tool to assess the positive therapeutic effects of rhGH therapy in adult GHD patients.