Clinical and metabolic effects of first-line treatment with somatostatin analogues or surgery in acromegaly: a retrospective and comparative study.

To evaluate the metabolic effects of first-line somatostatin analogues or surgery in acromegaly. Retrospective, comparative, 12-month follow-up. Two hundred and thirty one patients (123 men, age 47.32 ± 14.63 years) with active acromegaly, first line treatments were somatostatin analogues in 151 (65.4%) and surgery in 80 (34.6%). Metabolic syndrome (MS) parameters, glucose, insulin and GH during oral glucose tolerance test, stimulated insulin sensitivity by insulin sensitivity index (ISI Matsuda), early and total insulin-secretion rate by insulinogenic index and AUC(INS), visceral adiposity function, expressed by visceral adipose index (VAI). Somatostatin analogues treatment improved all MS parameters and significantly reduced fasting glucose (P < 0.001), HbA1c (P = 0.014) and the prevalence of DM (P = 0.003) when disease control was achieved. Both somatostatin analogues and surgery improved ISI Matsuda (P < 0.001) and reduced AUC(INS) (P < 0.001) and VAI (P < 0.001 and P = 0.003, respectively). Only in controlled somatostatin analogues-treated patients a significant reduction in insulinogenic index (P = 0.010) was observed. ISI Matsuda showed a significant independent correlation with IGF-1 levels (β = -0.258; P = 0.001) and VAI score (β = -0.430; P < 0.001). VAI was independently correlated with IGF-1 (β = 0.183; P = 0.004). Both somatostatin analogues and surgery can safely be used as first-line therapy in acromegaly, without any untoward effects on glucose tolerance. The control of acromegaly is the main determinant of beneficial effects on general features of insulin sensitivity. VAI could represent an additional link between disease control and insulin sensitivity.