Endocrine Abstracts

Introduction: Growth Hormone deficiency (GHD) is frequent in patients with human immunodeficiency virus 1 (HIV-1), undergoing highly active antiretroviral therapy. GHD seems to depend on HIV-related lipodystrophy and to be less frequent in women.

Aim of the study: To investigate the association of gender, body composition and GH/IGF1 axis, and to clarify whether GHD in HIV-infected patients is functional or a clinical entity.

Methods: We compared 47 HIV-infected patients prospectively enrolled, with 36 hypopituitary subjects retrospectively selected reviewing record charts. We evaluated basal serum GH, IGF1, GH peak and area under the curve (AUC) after standard GH Releasing Hormone+Arginine test; BMI, waist and hip circumference and body composition by dual-energy X-ray absorptiometry (DEXA). Data were analyzed by nonparametric Mann–Whitney test.

Results: HIV-infected patients had higher GH peak, AUC, and IGF1 (P<0.0001). BMI (P=0.003), total (P<0.0001) and trunk fat mass (P=0.0003) were higher in hypopituitary patients; waist to hip ratio (WHR) was higher in HIV-infected patients (P<0.0001). GH peak was lower in hypopituitary men than women (P=0.001). Men showed higher WHR (P=0.0082), total (P=0.0002) and trunk lean mass (P=0.0008), while women had higher total (P=0.0017) and trunk fat mass (P=0.0176). No gender differences were found in HIV-infected patients. GH peak, AUC, and IGF1 were higher (P<0.0001) in HIV-infected than hypopituitary men. No difference was found in women.

Conclusions: GHD seems to be worse in hypopituitary patients, suggesting that primary pituitary disease affects GH/IGF1 axis more than HIV-1. Moreover, fat distribution more than fat mass per se seems to affect GH/IGF1 axis in HIV-infected patients, since they have lower BMI but higher WHR. Furthermore, men seem to have a worse deficit than women, suggesting a possible role of gender in GH/IGF1 status. These differences could help distinguishing functional from clinical GHD in HIV-infected subjects, and better targeting treatment strategies.