Studies on the Role of Insulin-like Growth Factor -1 in Left Ventricular Hypertrophy in Essential Hypertension

Abstract

Background It is now well accepted that left ventricular hypertrophy (LVH) in hypertension (HT) is caused not only by hemodynamic but also by humoral factors. The experimental data indicates that in cardiac hypertrophy an important role may play insulin-like growth factor -1 (IGF-I). To gain insight into the possible involvement of IGF-1 in LVH, the plasma level of this factor were measured in HT patients and the relation between IGF-1 and LVMI, mean blood pressure (MBP) and other humoral factors were assessed.
Methods 121 HT patients(pts) of age 17-79 (mean 48 ± 15.3) were divided into three groups: I - 53 pts with mild HT, II-44 pts with moderate HT and III-24 pts with severe HT Control group consisted of 39 healthy normotensives. LV mass was assessed echocardiographically and plasma levels of IGF-l, plasma renin activity (PRA) and aldosterone (ALDO) were measured by radioimmunoassay in each pts and controls.
Results LVH was found in 35.8% pts with mild HT, in 68.18% pts with moderate HT and in 100% pts with severe HT. The levels of IGF-1, PRA and ALDO were significantly higher in pts with severe and moderate HT compared to the other groups (p < 0.001) and higher in patients with LVH compared to those without LVH (p < 0.001). There was significant correlation between IGF-1 and LVMI and MBP and between IGF-1 and PRA and ALDO in pts with moderate and severe HT and especially in HT pts with LVH.
Conclusions Increased plasma level of IGF-1 in pts in advanced HT and with LVH and significant correlation between IGF-1 and LVMI suggests that IGF-1 contributes to LVH in hypertensive patients. Significant correlation between IGF-1 level and PRA and aldosterone level indicates their close relationship in patomechanism of LVH.