Effect of Growth Hormone Replacement Therapy on Plasma Brain Natriuretic Peptide Concentration, Cardiac Morphology and Function in Adults with Growth Hormone Deficiency

Objective: The impact of growth hormone (GH) replacement on plasma brain natriuretic peptide (BNP) in association with cardiac morphology and function in adults with growth hormone deficiency (GHD) was evaluated. Subjects and Methods: Fifty nine adult patients with GHD (29 men, age 19-59 years) received a starting dose of 0.1-0.2 mg/day recombinant GH, which was subsequently adjusted to the 50th percentile of normal serum insulin-like growth factor (IGF-1) over a 6 month period. Plasma BNP and IGF-I levels before, 3 and 6 months after treatment were determined, as were the echocardiographic data, such as ejection fraction (EF), left ventricular end-diastolic volume (LVEDV), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVST), posterior wall thickness (PWT), left ventricular mass (LVM), E/A wave and deceleration time (DT). Results: Mean plasma BNP levels (53.1 +/- 8 pg/ml) and echocardiographic parameters were within the normal range at baseline, although men had higher LVM, IVST, PWT, LVEDV and LVEDD, respectively. A significant decrease in plasma BNP was observed after 6 months (27 +/- 5.6 pg/ml, P < 0.05). No significant changes in echocardiographic parameters were observed except for a mild tendency to increase in LVM, and a borderline decrease in DT (181 +/- 8.1 vs. 155 +/- 9 ms, P < 0.01). Conclusions: Six months GH replacement therapy induced a significant decrease in plasma BNP levels despite the majority of patients having plasma BNP within the normal range at baseline. A borderline decrease in diastolic deceleration time was observed, the clinical significance of which is unclear.