Long-term depot specific changes in adipose tissue after treatment of acromegaly

Abstract

Context Patients with active acromegaly present a decreased adipose tissue (AT) mass, and short-term studies show that treatment leads to AT depot specific gain. However, it remains unclear if the increase is persistent in the long-term perspective and/or is sex dependent. Design To characterize the depot specific changes of AT after treatment of acromegaly and identify contributing factors. Methods Adipose tissue, including visceral (VAT), subcutaneous (SAT), total (TAT) and android to gynoid ratio (A/G ratio) were measured by Dual Energy X-ray Absorptiometry (DXA) at diagnosis (n=62), and after treatment at short-term (median (IQR) 1.9 (1.5-2.3)) and long-term 5.5 (3.9-9.5) years, and correlated to clinical and biochemical measurements. Growth hormone (GH), insulin-like growth factor I (IGF-1), glucose and HbA1c levels, gonadal status, and the presence of diabetes mellitus were recorded. Remission status was assessed at the long-term visit (IGF-1/ULN≤1.3). Differences in the temporal course of AT from baseline to short- and long-term follow-up according to sex, diabetes, gonadal and remission status were evaluated by mixed model analysis, adjusted for age. Results Despite a stable body mass index, VAT and A/G ratio increased at both time points, whereas SAT mainly increased at short-term, plateauing afterwards (p<0.05 for all). VAT and A/G ratio were higher in men (p=0.035 and p<0.001), and the A/G ratio increased more than in women (p=0.003). Glucose and HbA1c decreased short-term (p<0.05) and remained stable at long-term. The increase in AT depots correlated with the decrease of disease activity at long-term. Remission status had no effect on changes in AT mass during follow-up. Conclusion Treatment of acromegaly leads to an increase in AT mass in a depot and sex specific manner both at short-term and long-term follow-up. Glucose metabolism improves rapidly after disease control and persists.